[Objective] This study aimed to provide basis for rational fertilizer application of wheat in fluvo-aquic soil in the northwest of Shandong Province.[Method] In this paper,the treatments of reduced N,P and K were set ...[Objective] This study aimed to provide basis for rational fertilizer application of wheat in fluvo-aquic soil in the northwest of Shandong Province.[Method] In this paper,the treatments of reduced N,P and K were set in order to explore the effects of fertilizer recommendation based on ASI systematic approach on wheat yield,agronomic efficiency and recovery rate of nutrients.[Result] Nitrogen was the main limiting factor for wheat production in that area,followed by phosphorus,and the third was potassium.Compared with the optimum treatment （OPT）,the reduction of N,P and K reduced the grain yield obviously,which came up to 22.4％,14.4％ and 13.4％ respectively.There were no obvious differences in grain yield among Farmer＇s Fertilization Practice （FP）,60％ OPT-N and OPT treatment.[Conclusion] Agronomic efficiency of N,P and K was 6.3,12.9 and 10 kg/kg respectively.The recovery rates of N,P and K in wheat season were 16.41％,17.27％ and 27.27％ respectively.展开更多
A batch experiment was performed to investigate nonequilibrium adsorption behavior of atrazine （2-chloro-4-ethylamino-6-isopropylamlno-1,3,5-triazlne） on a fluvo-aquic soil. The amount of atrazine sorbed increased w...A batch experiment was performed to investigate nonequilibrium adsorption behavior of atrazine （2-chloro-4-ethylamino-6-isopropylamlno-1,3,5-triazlne） on a fluvo-aquic soil. The amount of atrazine sorbed increased with increasing adsorption contact periods. For a range of initial atrazlne concentrations, the percentage of atrazine sorbed within 24 h ranged from 24% to 77% of the observed total amount sorbed for the longest contact period; when adsorption contact periods were more than 72 h, the deviations in curves fitted using a nonlinear Freundllch equation gradually became less. The opposite trend was observed for the atrazine concentrations in solution. The effect of adsorption contact periods on atrazine adsorption behavior was evaluated by interpreting the temporal variations in linear and nonlinear Freundlich equation parameters obtained from the phase-distribution relationships. As the adsorption contact period increased, the nonlinear Freundlich capacity coefficient kf showed a significant linear increase （r^2 = 0.9063, P 〈 0.001）. However, a significant negative linear correlation was observed for the nonlinear coefficient n, a dimensionless parameter （r^2 = 0.5666, P 〈 0.05）. Furthermore, the linear distribution coefficient kd ranged from 0.38 to 1.44 and exhibited a significant linear correlation to the adsorption contact period （r^2 = 0.72, P 〈 0.01）. The parameters kf and n obtained from a time-dependent isotherm rather than the distribution coefficient kd estimated using the linear Freundlich equation were more appropriate to predict the herbicide residue in the field and thus more meaningful for environmental assessment.展开更多
The improvement of soil productivity depends on a rational input of water and nutrients, optimal field management, and the increase of basic soil productivity（BSP）. In this study, BSP is defined as the productive ca...The improvement of soil productivity depends on a rational input of water and nutrients, optimal field management, and the increase of basic soil productivity（BSP）. In this study, BSP is defined as the productive capacity of a farmland soil with its own physical and chemical properties for a specific crop season under local field management. Based on 19-yr data of the long-term agronomic experiments（1989–2008） on a fluvo-aquic soil in Zhengzhou, Henan Province, China, the decision support system for agrotechnology transfer（DSSAT ver. 4.0） crop growth model was used to simulate yields by BSP of winter wheat（Triticum aestivium L.） and summer maize（Zea mays L.） to examine the relationship between BSP and soil organic carbon（SOC） under long-term fertilization. Five treatments were included：（1） no fertilization（control）,（2） nitrogen, phosphorus and potassium fertilizers（NPK）,（3） NPK plus manure（NPKM）,（4） 1.5 times of NPKM（1.5NPKM）, and（5） NPK plus straw（NPKS）. After 19 yr of treatments, the SOC stock increased 16.7, 44.2, 69.9, and 25.2% under the NPK, NPKM, 1.5NPKM, and NPKS, respectively, compared to the initial value. Among various nutrient factors affecting contribution percentage of BSP to winter wheat and summer maize, SOC was a major affecting factor for BSP in the fluvo-aquic soil. There were significant positive correlations between SOC stock and yields by BSP of winter wheat and summer maize（P〈0.01）, and yields by BSP of winter wheat and summer maize increased 154 and 132 kg ha^（–1） when SOC stock increased 1 t C ha^（–1）. Thus, increased SOC accumulation is a crucial way for increasing BSP in fluvo-aquic soil. The manure or straw combined application with chemical fertilizers significantly enhanced BSP compared to the application of chemical fertilizers alone.展开更多
Experiments including two in laboratory and one in greenhouse were carried out to study non- exchangeable magnesium release from fluvo-aquic soils sampled from Daxing and changping counties located in the suburbs of B...Experiments including two in laboratory and one in greenhouse were carried out to study non- exchangeable magnesium release from fluvo-aquic soils sampled from Daxing and changping counties located in the suburbs of Beijing and Mg relative availability of the two soils to plants. In a batch experiment in laboratory the soils were incubated under wet conditions and alternation of dry and wet conditions and determined for amount of Mg released at the 4th, 8th and 12th week, respectively, after extraction of exchangeable Mg with 1 mol L-1 NH4Ac. The amount of Mg released from the soil of Daxing was higher than from the soil of Changping, which was in accordance with the fact that the soil of Daxing had higher contents of all forms of Mg than that of Changping. There was little difference in Mg release from soils between wet conditions and alternation of dry and wet conditions. About 1%~2% of the total non-exchangeable Mg might be released within 12 weeks of incubation, restoring about 30%~35% of the original soil exchangeable Mg. Results of the experiment on kinetics of Mg release from the soils through continuous extractions with 0.5 mol L-1 NH4Ac (pH 7.0) on a continuous flow apparatus in laboratory showed that Mg released rapidly in the beginning, decreased sharply with time and kept stable at 60 and 240 min for the soils of Changping and Daxing, respectively. Among the five mathematical models used to describe the kinetics of Mg release, the parabolic diffusion equation best fitted the cumulative Mg release, indicating that diffusion of Mg out of the soils might be the controlling process. The experiment of exhaustive cropping with 1 crop of tomato (Lycopersicon esculentum Mill.) followed by six crops of corn (Zea mays L.) in greenhouse showed that soil exchangeable Mg decreased remarkably with cropping. After three crops, the percentage of the total plant Mg uptake that came from soil non-exchangeable Mg was 29.5% for the soil from Changping and 35% for the soil from Daxing. About 50% of the total Mg uptake by plants in the six crops was believed to come from the soil non-exchangeable Mg form.展开更多
In order to verify organic carbon cycle under conservation tillage condition and the promotion mechanism of soil fertility and offer scientific theory support for the popularization and application of conservation til...In order to verify organic carbon cycle under conservation tillage condition and the promotion mechanism of soil fertility and offer scientific theory support for the popularization and application of conservation tillage technological, the research investigated effects of different tillage treatments on the content of total organic car- bon, total nitrogen and different components of them in fluvo-aquic soil based on a long-term experiment site of conservation tillage. The research revealed effects of conservation tillage on the content of carbon, nitrogen in fluvo-aquic soil by study the distribution of soil total organic carbon, total nitrogen, dissolved organic carbon, dissolved organic nitrogen, microbial biomass carbon, liable carbon in different soil depth under different tillage treatments. The results showed that compared to con- ventional tillage treatment, contents of soil total organic carbon under intermittent tillage （tillage once every 2 or 4 years） and no-tillage treatment improved by 1.81%, 6.43%, 14.04%, respectively and contents of soil total nitrogen went up by 0.80%, 10.04%, 7.93%, respectively. Contents of soil total organic carbon and total nitrogen in 10-20 cm soil layer under no-tillage treatment were significantly lower than the other treatments. Under the condition of straw returned, intermittent tillage and no- tillage could significantly improve the content of soil dissolved organic carbon and ni- trogen in 0-5 cm and 5-10 cm soil. Compared to conventional tillage treatment, content of soil microbial biomass carbon and liable carbon in 0-5 cm soil under in- termittent tillage and no-tillage were improved in varying degrees. Content of soil microbial biomass carbon in 10-20 cm soil layer under no-tillage treatment was sig- nificantly lower than the other treatments. Straw returning had improved the content of soil total organic carbon, total nitrogen, dissolved organic carbon and other com- ponents of active organic carbon in varying degrees. In general, conservation tillage measures could increase carbon and nitrogen storage in 0-5 cm soil layer, the negative effects of ＂nutrients enrichment in surface＂ under no-tillage condition could be ameliorated by intermittent tillage.展开更多
This study was conducted to investigate the effects of long-term located fertilization on soil phosphorus,the changes of soil available phosphorus(OlsenP),the evolution of soil total phosphorus(TP)and the ratio change...This study was conducted to investigate the effects of long-term located fertilization on soil phosphorus,the changes of soil available phosphorus(OlsenP),the evolution of soil total phosphorus(TP)and the ratio change of Olsen-P to TP(PAC)by 33-year fertilization experiments in winter wheat-summer maize rotation system in Shandong fluvo-aquic soil.Eight treatments were designed as no fertilization(CK),nitrogen fertilizer(N),nitrogen and phosphate fertilizer(NP),nitrogen and potassium fertilizer(NK),phosphate and potassium fertilizer(PK),nitrogen-phosphate-potassium fertilizer(NPK),reduced NPK fertilizer(N(15)PK),and increased NPK fertilizer(N_(25)PK).Meanwhile,eight organic fertilizer-added treatments were designed based on the application of inorganic fertilizer the same as the above ones.The results showed that TP,Olsen-P and PAC of treatments added with organic fertilizer were higher than those without organic fertilizer,and those of the treatments applied with phosphate fertilizer were higher than those of no phosphate fertilizer.With the increase of years,soil P pool decreased due to crop absorption,nutrient loss and morphological transformation and other causes under the treatments of without and only phosphate fertilizer,while remained stable under the treatments added with organic fertilizer.The PAC values were generally lower in fluvo-aquic soil,and it could be improved by the application of organic fertilizer.On the whole,the application of chemical phosphate fertilizer combined with organic fertilizer could improve the phosphorus content in soil and ensure the supply of phosphorus nutrition.This study would provide scientific basis for fertilization management and soil fertility in fluvo-aquic soil.展开更多
[Objective] The research aimed to study the effects of fertilization on soil remediation.[Method]Pot fertilizer tests were conducted to remedy the soils which had off-balanced in nutrients resulted by long-term unreas...[Objective] The research aimed to study the effects of fertilization on soil remediation.[Method]Pot fertilizer tests were conducted to remedy the soils which had off-balanced in nutrients resulted by long-term unreasonable fertilization.[Result]The results showed that applying NPK fertilizers with manure was the best method to restore the soil nutrients and increase soil fertility and crop yield;NPK and NP fertilizers could balance soil fertility and increase crop yields,the effects were the same and next to MNPK.Phosphate and nitrogen respectively had the similar restoring effect with NPK fertilizers on soil from long-term NK and PK treatments.[Conclusion]Crops in soil with long-term applying NPK fertilizers had strong dependence on fertilizers.The yields of corn and wheat decreased by 78.6% and 52.8% respectively after stopping applying fertilizers.Meanwhile,The yields of corn and wheat increased by 112% and 182% respectively after stopping applying fertilizers in NK treatment as well as 15.1% and 59% in PK treatment.Manure had strong and last effect on increasing yield.展开更多
The concentration of soil Olsen-P is rapidly increasing in many parts of China, where P budget(P input minus P output) is the main factor influencing soil Olsen-P. Understanding the relationship between soil Olsen-P a...The concentration of soil Olsen-P is rapidly increasing in many parts of China, where P budget(P input minus P output) is the main factor influencing soil Olsen-P. Understanding the relationship between soil Olsen-P and P budget is useful in estimating soil Olsen-P content and conducting P management strategies. To address this, a long-term experiment(1991–2011) was performed on a fluvo-aquic soil in Beijing, China, where seven fertilization treatments were used to study the response of soil Olsen-P to P budget. The results showed that the relationship between the decrease in soil Olsen-P and P deficit could be simulated by a simple linear model. In treatments without P fertilization(CK, N, and NK), soil Olsen-P decreased by 2.4, 1.9, and 1.4 mg kg^(–1) for every 100 kg ha^(–1) of P deficit, respectively. Under conditions of P addition, the relationship between the increase in soil Olsen-P and P surplus could be divided into two stages. When P surplus was lower than the range of 729–884 kg ha^(–1), soil Olsen-P fluctuated over the course of the experimental period with chemical fertilizers(NP and NPK), and increased by 5.0 and 2.0 mg kg^(–1), respectively, when treated with chemical fertilizers combined with manure(NPKM and 1.5 NPKM) for every 100 kg ha^(–1) of P surplus. When P surplus was higher than the range of 729–884 kg ha^(–1), soil Olsen-P increased by 49.0 and 37.0 mg kg^(–1) in NPKM and 1.5 NPKM treatments, respectively, for every 100 kg ha^(–1) P surplus. The relationship between the increase in soil Olsen-P and P surplus could be simulated by two-segment linear models. The cumulative P budget at the turning point was defined as the "storage threshold" of a fluvo-aquic soil in Beijing, and the storage thresholds under NPKM and 1.5 NPKM were 729 and 884 kg ha^(–1)P for more adsorption sites. According to the critical soil P values(CPVs) and the relationship between soil Olsen-P and P budget, the quantity of P fertilizers for winter wheat could be increased and that of summer maize could be decreased based on the results of treatments in chemical fertilization. Additionally, when chemical fertilizers are combined with manures(NPKM and 1.5 NPKM), it could take approximately 9–11 years for soil Olsen-P to decrease to the critical soil P values of crops grown in the absence of P fertilizer.展开更多
Organic manure application is an important measure for high yield and good quality vegetable production, whereas organic manure is also a main source of residual antibiotic in soils. A 3-yr experiment was conducted on...Organic manure application is an important measure for high yield and good quality vegetable production, whereas organic manure is also a main source of residual antibiotic in soils. A 3-yr experiment was conducted on a fluvo-aguic soil in Tianjin of northern China. The objective of this study was to investigate the effects of different fertilization patterns on yield of six-sea- son vegetables with celery and tomato rotation, and dynamic change of tetracyclines residues in the soil during the sixth growing season （tomato season）. The field experiment comprised six treatments depending on the proportion of nitrogen of each type of fertilizer： 4/4 CN （CN, nitrogen in chemical fertilizer）, 3/4 CN＋1/4 MN （MN, nitrogen in pig manure）, 2/4 CN＋2/4 MN, 1/4 CN＋3/4 MN, 2/4 CN＋1/4 MN＋I/4 SN （SN, nitrogen in corn straw）, and CF （conventional fertilization, the amounts of nitrogen application were 943 and 912 kg N ha-1 for celery and tomato season, respectively）. In addition to CF treatment, the amount of nitrogen application in other treatments was greatly reduced and equal （450 and 450 kg N ha-1 for celery and tomato season, respectively）. Results showed that the combined application of 3/4 CN＋1/4 MN achieved the highest yield and economic benefit in the first four seasons, but addition of straw （2/4 CN＋1/4 MN＋I/4 SN treatment） performed better in the subsequent two seasons, and the average yields of 2/4 CN＋1/4 MN＋I/4 SN treatment were respectively higher by 9.9 and 12.8% than those of 4/4 CN treatment, and by 5.6 and 10.5% than those of CF treatment. The residual chlortet- racycline （CTC） in manure-amended soil for three consecutive years increased along with the increase of applied amount of pig manure. Under the same amount of pig manure application, content of CTC in straw-amended soil was obviously decreased compared with no straw-amended soil （3/4 CN＋1/4 MN treatment）, and averagely decreased by 41.9% for four sampling periods in the sixth season. Addition of crop straw facilitated the degradation of CTC in manure-amended soil. As a whole, the conventional fertilization was not the desirable pattern based on yield, economic benefit and environment, the optimal fertilization pattern with the highest yield and profit and the least soil chlortetracycline residue was the treatment of 2/4 CN＋1/4 MN＋I/4 SN under this experimental condition.展开更多
Soil P status, inorganic P fractions, and P sorption properties were studiedusing sandy fluvo-aquic horticultural soils, which are high in organic matter content for vegetableproduction in comparison with a soil used ...Soil P status, inorganic P fractions, and P sorption properties were studiedusing sandy fluvo-aquic horticultural soils, which are high in organic matter content for vegetableproduction in comparison with a soil used for grain crop production in Zhengzhou, Henan Province,China P fractions, Olsen-P, and OM were determined at different depths in the soil profile andsorption isotherm experiments were performed Most P in excess of plant requirements accumulated inthe topsoil and decreased with soildepth. Total P, inorganic P, and OM concentrations increased withcontinued horticultural use Olsen-P concentrations in the 0-20 cm depth of horticultural soils were9 to 25 times higher than those of the grain crop soil. A linear transformation of the Langmuirequation showed that the P adsorption maximum (491.3 mg P kg^(-1)) and the maximum phosphatebuffering capacity (162.1 L kg^(-1)) for 80--100 cm were greater in the grain crop soil than thehorticultural soils. Thus, the most immediate concern with excess P were in areas where heavy Pfertilizer was used for vegetable crops and where soil P sorption capacities were low due to sandysoils and high organic matter content.展开更多
The K+ adsorption kinetics of fluvo-aquic soil and cinnamon soil under different temperatureswere studied. The results showed: 1) The first order equations were the most suitable forfitting the adsorption under variou...The K+ adsorption kinetics of fluvo-aquic soil and cinnamon soil under different temperatureswere studied. The results showed: 1) The first order equations were the most suitable forfitting the adsorption under various temperature levels with constant K+ concentration indisplacing fluid. With temperature increasing, the fitness of Elovich equation increased,while those of power equation and parabolic diffusion equation decreased; 2)the apparentadsorption rate constant ka and the product of ka multiplied by the apparent equilibriumadsorption qincreased when temperature increased, while the apparent equilibrium adsorptionqreduced; 3)temperature influenced hardly the reaction order, the order of concentrationand adsorpton site were always 1 under various temperatures, if they were taken intoaccount simultaneously, the adsorption should be a two-order reaction process; 4)theGibbs free energy change △G of potassium adsorption were negative, ranged from -4444.56to -2450.63Jmol-1,and increased with temperature increasing, while enthalpy change △H,entropy change △S, apparent adsorption activation Ea, adsorption activation energy E1and desorption activation energy E2 were temperature-independent; 5)the adsorption wasspontaneous process with heat releasing and entropy dropping, fluvo-aquic soil releasedmore heat than cinnamon soil.展开更多
Differently sized soil aggregates,with non-uniform distribution of space and nutrients,provide spatially heterogeneous microenvironments for microorganisms and are important for controlling microbial community ecology...Differently sized soil aggregates,with non-uniform distribution of space and nutrients,provide spatially heterogeneous microenvironments for microorganisms and are important for controlling microbial community ecology and biogeochemistry in soils.Here,we investigated the prokaryotic communities within different aggregate-size fractions:macroaggregate(>0.25 mm),microaggre-gate(0.053–0.25 mm)and silt+clay(<0.053 mm).These were isolated from fluvo-aquic soils under 39-year fertilization strategies:no fertilizer(CK),chemical fertilizer(NPK),manure fertilizer(M),and combination of manure and chemical fertilizers(MNPK).The results showed that the proportion of macroaggregate,soil aggregate-associated organic carbon(SOC)content and aggregate stability were all significantly increased by both manure and chemical fertilizations.Organic fertilizations(M and MNPK)more effectively boosted formation and stability of macroaggregates and enhanced SOC concentration than NPK.The distribution patterns of microorganisms in aggregates were primarily shaped by fertilization and aggregate size.They explained 76.9%of the variance in bacterial community compositions.Fertilizations,especially with organic fertilizers primarily transitioned bacterial communities from slow-growing oligotrophic groups(e.g.,Chloroflexi)dominance to fast-growing copiotrophic groups(e.g.,Proteobacteria and Bacteroidetes)dominance across all aggregate sizes.Macroaggregates possessed a more stable bacterial community and efficiency of resource transfer,while smaller aggregates increased antagonism and weakened mutualism among bacterial communities.Overall,combination of manure and chemical fertilizers was crucial for increasing SOC content and aggregation,leading to a clear shift in bacterial community structures at aggregate scale.展开更多
To maintain soil quality under long-term saline water irrigation,the influence of manure on soil physical properties was examined.Long-term saline irrigation has been conducted from 2015 to 2024 at the Nanpi Eco-Agric...To maintain soil quality under long-term saline water irrigation,the influence of manure on soil physical properties was examined.Long-term saline irrigation has been conducted from 2015 to 2024 at the Nanpi Eco-Agricultural Experimental Station of Chinese Academy Sciences in the Low Plain of the North China Plain,comprising four irrigation treatments:irrigation once at the jointing stage for winter wheat with irrigation water containing salt at fresh water,3,4 and 5 g·L^(–1),and maize irrigation at sowing using fresh water.Manure application was conducted under all irrigation treatments,with treatments without manure application used as controls.The results showed that under long-term irrigation with saline water,the application of manure increased the soil organic matter content,exchangeable potassium,available phosphorus,and total nitrogen content in the 0–20 cm soil layer by 46.8%,117.0%,75.7%,and 45.5%,respectively,compared to treatments without manure application.The application of manure reduced soil bulk density.It also increased the proportion of water-stable aggregates and the abundance of bacteria,fungi,and actinomycetes in the tillage soil layer compared to the controls.Because of the salt contained in the manure,the application of manure had dual effects on soil salt content.During the winter wheat season,manure application increased soil salt content.The salt content was significantly reduced during the summer maize season,owing to the strong salt-leaching effects under manure application,resulting in a smaller difference in salt content between the manure and non-manure treatments.During the summer rainfall season,improvements in soil structure under manure application increased the soil desalination rate for the 1 m top soil layer.The desalination rate for 0–40 cm and 40–100 cm was averagely by 39.1%and 18.9%higher,respectively,under manure application as compared with that under the nomanure treatments.The yield of winter wheat under manure application was 0.12%lower than that of the control,owing to the higher salt content during the winter wheat season.In contrast,the yield of summer maize improved by 3.9%under manure application,owing to the increased soil nutrient content and effective salt leaching.The results of this study indicated that manure application helped maintain the soil physical structure,which is important for the long-term use of saline water.In practice,using manure with a low salt content is suggested to reduce the adverse effects of saline water irrigation on soil properties and achieve sustainable saline water use.展开更多
[Objective]Vegetation restoration is an effective strategy for ecological improvement;however,inappropriate vegetation establishment can induce soil desiccation,thereby threatening ecosystem stability.Therefore,elucid...[Objective]Vegetation restoration is an effective strategy for ecological improvement;however,inappropriate vegetation establishment can induce soil desiccation,thereby threatening ecosystem stability.Therefore,elucidating the global response patterns of soil moisture to vegetation restoration and identifying research hotspots are critical for guiding ecological construction in arid regions.[Methods]We reviewed 6,152 articles concerning soil moisture and vegetation retrieved from the Web of Science platform.Using VOSviewer,we conducted analyses of keyword co-occurrence,publication trends,and research hotspots to systematically delineate the evolving trends in this field.[Results]The results indicate a significant increasing trend in the number of publications since 2000.Global research keywords are categorized into seven clusters,including vegetation,soil moisture,rainfall-erosion-infiltration,spatial heterogeneity,and climate change.In terms of highly cited papers in 2024,China and the United States maintain a significant lead.Global research demonstrates a strong dependency on typical regional geographical features(such as climate types and topography),exhibiting differentiated research focuses.Furthermore,studies extend beyond soil moisture itself to deeply couple with ecological processes such as vegetation restoration,soil respiration,carbon cycling,and hydrothermal conditions.[Conclusions]The long-term ecological effects of afforestation in arid regions remain unclear,and empirical data from key regions highlight the current urgency.Future research should integrate climate change dynamics,innovate monitoring methodologies,and deepen the understanding of regional differentiation to provide scientific support for the adaptive management of vegetation in arid regions.展开更多
39 soil samples surrounding a lead-zinc mining area in Guangxi were collected,and the contents of Pb,Hg,Cd,Cr,As,Cu,Zn,and Ni were determined to investigate the pollution characteristics and sources of heavy metals.Ar...39 soil samples surrounding a lead-zinc mining area in Guangxi were collected,and the contents of Pb,Hg,Cd,Cr,As,Cu,Zn,and Ni were determined to investigate the pollution characteristics and sources of heavy metals.ArcGIS inverse distance weight difference method was used to analyze the characteristics of pollution distribution,and single-factor pollution index,Nemerow comprehensive pollution index,ground accumulation index,and potential ecological risk index were selected to evaluate the characteristics of heavy metal pollution.Based on correlation analysis,the absolute principal component-multiple linear regression(APCS-MLR)and positive definite matrix factorization(PMF)models were used to analyze the sources of soil heavy metals.The results showed that the average concentrations of all eight heavy metals exceeded both national and Guangxi soil background values.Hg,Cd,and Zn exhibited high variation(greater than 0.5),indicating significant external disturbances,and their spatial distribution was closely related to mining activity locations.The single-factor pollution index evaluation indicated varying degrees of pollution risk for Cd,Zn,and As,with Cd and Zn being the most severe pollutants,as 69.23%and 30.77%of the samples fell into the moderate pollution or higher category.The geoaccumulation index analysis ranked the mean pollution levels of the eight elements as follows:Zn>Cd>Ni>Pb>Cu>Cr>Hg>As,with Cd and Zn showing the most severe contamination,and 51.28%of the samples exhibiting moderate or higher pollution levels.The Nemerow comprehensive pollution index evaluation showed that 74.35%of soil samples were classified as moderate to heavy pollution.The potential ecological risk index assessment indicated significant ecological risks posed by Cd and Zn,with 82.05%and 5.12%of the samples classified as causing strong to extreme ecological risks,respectively.The source apportionment analysis revealed minor differences between the two models.The APCS-MLR model identified three pollution sources and their contribution rates:anthropogenic mining sources(31.13%),parent material sources(40.38%),and unidentified sources(28.49%).The PMF model identified three pollution sources with contribution rates of anthropogenic mining sources(26.10%),parent material sources(46.96%),and a combined traffic and agricultural source(26.61%).Pb,Hg,Cd,and Zn mainly originated from mining activities;Cr,As,and Ni were primarily derived from the parent material,while Cu was predominantly attributed to traffic and agricultural sources.These findings provide a scientific basis for the prevention and control of heavy metal pollution in mining areas.展开更多
Soil respiration is the key process driving CO_(2) exchange between forest soils and the atmosphere and regulated by soil organic carbon(SOC)characteristics and extracellular enzyme activities.However,the direction an...Soil respiration is the key process driving CO_(2) exchange between forest soils and the atmosphere and regulated by soil organic carbon(SOC)characteristics and extracellular enzyme activities.However,the direction and magnitude of the effects of stand density on labile SOC fractions,extracellular enzymes,and soil respiration across plantation ages remain unclear.We constructed enhanced soil respiration models using heterogeneous soil data under density regulation to better characterize soil processes.Study plots encompassing stand-density gradients were implemented in Larix principis-rupprechtii plantations spanning three age-class strata.During the growing season,systematic measurements were conducted on soil respiration rates,labile organic carbon fractions,and extracellular enzyme activities.A process-driven soil respiration model was developed by integrating nonlinear mixed-effects modeling frameworks with measured data.The moderate density stands showed increases in soil respiration(Rs),microbial biomass carbon(MBC),light fraction organic carbon(LFOC),β-1,4-glucosidase(BGC),andβ-N-acetyl glycosaminidase+leucine aminopeptidase(NAG+LAP).In 36a and 48a stands,the moderate-density stands NAG+LAP had a~35%increase compared to other density levels,while readily oxidized carbon(ROC)concentrations showed a significant~30%-50%reduction.All labile organic carbon components were stable with age,so that soil microorganisms were promoted to acquire C,N,and P.Temperature,moisture,MBC,BGC,and NAG+LAP were essential factors that affected soil respiration.Stand density has important impacts on soil respiration as it regulates the soil organic carbon and activities of extracellular enzymes.The roles of temperature,microbial biomass carbon,soil organic carbon and dissolved organic carbon are complex and directly affect autotrophic and heterotrophic respiration and regulate soil respiration by influencing microbial C and N acquisition.A mixed-effects model with nested stand density and age mathematically optimized the soil respiration model,enabling enhanced characterization of covariation patterns of soil respiration with related soil carbon pool variables.展开更多
Panax species are globally recognized for their high medicinal and economic value,yet large-scale cultivation is constrained by high production costs,progressive soil acidification,and persistent soil-borne diseases.A...Panax species are globally recognized for their high medicinal and economic value,yet large-scale cultivation is constrained by high production costs,progressive soil acidification,and persistent soil-borne diseases.Although various soil improvement strategies have been tested,a comprehensive synthesis of their comparative effectiveness has been lacking.Here,we conducted a meta-analysis of 1381 observations from 54 independent studies to evaluate the effects of conventional fertilizers,microbial fertilizers,organic amendments,and inorganic amendments on Panax cultivation.Our results demonstrate that microbial fertilizers,organic amendments,and inorganic amendments significantly increased soil pH,thereby ameliorating soil acidification.Among them,organic amendments significantly enhanced the content of soil organic carbon,available nitrogen,and available phosphorus,alongside a notable increase in microbial diversity(Chao1 and ACE indices,which increased by 9%and 17%,respectively).Moreover,our analysis revealed that while microbial fertilizers,organic amendments,and inorganic amendments(except conventional fertilizers)reduced the disease index of Panax plants,organic amendments demonstrated absolute superiority in promoting plant height,root dry weight,root fresh weight,and root length.By quantitatively integrating multi-source evidence,this study provides novel mechanistic insights and practical recommendations that extend beyond local practices,offering guidance for sustainable ginseng cultivation and broader medicinal plant production systems worldwide.展开更多
One of the research hotspots in geotechnical engineering is the solidification of problematic soil foundations. However, the traditional materials, such as Portland cement, lime, and various types of chemical solution...One of the research hotspots in geotechnical engineering is the solidification of problematic soil foundations. However, the traditional materials, such as Portland cement, lime, and various types of chemical solutions, typically cause CO_(2) emissions and environmental pollution. Geopolymer is a newly proposed method for soil solidification, offering an environmentally friendly and effective solution. Given that soils typically consist of diverse compositions, an optimal soil stabilization technique should be versatile enough to be applied across various soil types, ensuring consistent strength outcomes with minimal variations among different soil compositions. In this study, three commonly used geopolymers(fly ash, ground granulated blast-furnace slag, and metakaolin) were utilized to stabilize silt, loess, silica sand, calcareous sand, and gravel, representing a diverse range of soils. The mechanical properties and microstructures of both geopolymers and geopolymerstabilized soils were analyzed. The findings indicated that the strength of stabilized coarse cohesionless soils was primarily influenced by the mechanical properties of the geopolymers themselves, with minimal impact from the inherent properties of the soil. However, the effectiveness of stabilizing cohesive soil may show significant discrepancies compared to the mechanical properties of geopolymer materials when certain types of geopolymers, like metakaolin, are employed. Higher strength is typically achieved through a denser structure(with fewer pores) and the presence of products with a higher degree of polymerization. Additionally, ground granulated blast-furnace slag exhibited excellent stability and superior strength when compared to other types of geopolymers. The present research establishes a basis for selecting geopolymers to stabilize a range of soils, including those with non-uniform compositions and diverse components.展开更多
Green manuring is essential for improving soil quality and nutrient uptake.With the gradual depletion of phosphorus(P)resources,more attention is being paid to the role of green manures in cultivation systems,such as ...Green manuring is essential for improving soil quality and nutrient uptake.With the gradual depletion of phosphorus(P)resources,more attention is being paid to the role of green manures in cultivation systems,such as maize-green manure intercropping,to find possible pathways for enhancing soil P utilization.A maize-green manure intercropping experiment was started in 2009 to investigate the effects and mechanisms for enhancing P uptake and yield in maize.Three species of green manures(hairy vetch(HV),needle leaf pea(NP),sweet pea(SP))and a sole maize treatment(CK)were used,resulting in four treatments(CK,HVT,NPT,and SPT)in the experiment.During 2020-2023,the intercropping treatments enhanced maize yields in 2020 and 2021,particularly in HVT with increases of 13.7%(1.96 t ha^(-1))and 13.0%(2.13 t ha^(-1))compared with CK,respectively.Grain P accumulation of maize was significantly higher in the intercropping treatments than CK in 2020,2021,and 2023,and with an average increase of 10.6%over the four years(5.2% for NPT,10.8% for SPT and 15.9% for HVT)compared with CK.Intercropping promoted maize growth with a greater root length density and a higher organic acid release rate.HVT changed the soil properties more dramatically than the other treatments,with increases in the acid phosphatase and alkaline phosphatase activities of 29.8 and 38.5%,respectively,in the topsoil(0-15 cm),while the soil p H was reduced by 0.37 units compared to CK(p H=8.44).Intercropping treatments facilitated the conversion of non-labile P to mod-labile P and stimulated the growth of soil bacteria in the topsoil.Compared with CK,the relative abundance of Gemmatimonadota,known for accumulating polyphosphate,and Actinobacteriota,a prominent source of bioactive compounds,increased significantly in the intercropping treatments,especially in HVT and SPT.A PLS-PM analysis showed that intercropping promoted soil P mobilization and the enrichment of beneficial bacteria by regulating maize root morphology and physiology.Our results highlight that maize-green manure intercropping optimizes root traits,soil properties and bacterial composition,which contribute to greater maize P uptake and yield,providing an effective strategy for sustainable crop production.展开更多
Soil organic carbon(SOC)dynamics significantly influence ecosystem carbon source-sink balance,particularly in agroecosystems.However,uncertainty remains regarding optimal land use types for maximizing farmland carbon ...Soil organic carbon(SOC)dynamics significantly influence ecosystem carbon source-sink balance,particularly in agroecosystems.However,uncertainty remains regarding optimal land use types for maximizing farmland carbon storage across different soil types,and identifying effective land management practices for enhanced carbon accumulation is essential for reducing agricultural emissions and strengthening carbon sinks.This study examined SOC variations in eastern Yunnan’s subtropical highlands(2,132 sites),analyzing topsoil(0–20 cm)across five land uses(dryland,irrigated land,forestland,grassland and plantation)of five soil types(red,yellow,yellowbrown,brown,purple).The investigation explored relationships between SOC and edaphic factors(26 elements)to determine SOC influencing factors.The study area demonstrated a mean SOC content of 27.78 g kg^(–1),with distinct spatial heterogeneity characterized by lower values in the southwestern sector and higher concentrations in the northeastern region.Brown soils displayed the highest SOC content(P<0.05),followed by yellow-brown then red,yellow,and purple soils.Irrigation significantly enhanced SOC storage,particularly in brown soils where irrigated land contained 2.2-,2.4-,and 1.6-times higher SOC than forestland,grassland,and dryland,respectively.Similar irrigation benefits occurred in purple,yellow,and yellow-brown soils,indicating moisture limitation as the primary SOC constraint.Notably,SOC exhibited strong positive correlations with nitrogen,sulfur,and selenium.Nitrogen fertilization demonstrated dual benefits:enhancing SOC sequestration and promoting Se enrichment in crops,potentially supporting specialty agriculture.Although land use impacts on SOC varied across soil types(P>0.05),irrigation consistently emerged as the optimal management for carbon sink enhancement.These findings suggest that targeted water management could effectively reduce farmland carbon emissions in moisture-limited subtropical highlands.Strategic nitrogen application offers co-benefits for soil fertility and selenium biofortification,providing practical pathways for climate-smart agriculture in similar ecoregions.展开更多
文摘[Objective] This study aimed to provide basis for rational fertilizer application of wheat in fluvo-aquic soil in the northwest of Shandong Province.[Method] In this paper,the treatments of reduced N,P and K were set in order to explore the effects of fertilizer recommendation based on ASI systematic approach on wheat yield,agronomic efficiency and recovery rate of nutrients.[Result] Nitrogen was the main limiting factor for wheat production in that area,followed by phosphorus,and the third was potassium.Compared with the optimum treatment （OPT）,the reduction of N,P and K reduced the grain yield obviously,which came up to 22.4％,14.4％ and 13.4％ respectively.There were no obvious differences in grain yield among Farmer＇s Fertilization Practice （FP）,60％ OPT-N and OPT treatment.[Conclusion] Agronomic efficiency of N,P and K was 6.3,12.9 and 10 kg/kg respectively.The recovery rates of N,P and K in wheat season were 16.41％,17.27％ and 27.27％ respectively.
基金Project supported by the National Science Fund for Distinguished Young Scholars,China(No.40325001)the National Basic Research and Development Program of China(No.2002CB410805)the Asia-Link Program(No.CN/AsiaLink/001(81468)).
文摘A batch experiment was performed to investigate nonequilibrium adsorption behavior of atrazine （2-chloro-4-ethylamino-6-isopropylamlno-1,3,5-triazlne） on a fluvo-aquic soil. The amount of atrazine sorbed increased with increasing adsorption contact periods. For a range of initial atrazlne concentrations, the percentage of atrazine sorbed within 24 h ranged from 24% to 77% of the observed total amount sorbed for the longest contact period; when adsorption contact periods were more than 72 h, the deviations in curves fitted using a nonlinear Freundllch equation gradually became less. The opposite trend was observed for the atrazine concentrations in solution. The effect of adsorption contact periods on atrazine adsorption behavior was evaluated by interpreting the temporal variations in linear and nonlinear Freundlich equation parameters obtained from the phase-distribution relationships. As the adsorption contact period increased, the nonlinear Freundlich capacity coefficient kf showed a significant linear increase （r^2 = 0.9063, P 〈 0.001）. However, a significant negative linear correlation was observed for the nonlinear coefficient n, a dimensionless parameter （r^2 = 0.5666, P 〈 0.05）. Furthermore, the linear distribution coefficient kd ranged from 0.38 to 1.44 and exhibited a significant linear correlation to the adsorption contact period （r^2 = 0.72, P 〈 0.01）. The parameters kf and n obtained from a time-dependent isotherm rather than the distribution coefficient kd estimated using the linear Freundlich equation were more appropriate to predict the herbicide residue in the field and thus more meaningful for environmental assessment.
基金supported by the National Basic Research Program of China(973 Program,2011CB100501)the Key Technologies R&D Program of China during the 12th Five-Year Plan period(2015BAD22B03)+1 种基金the National High-Tech R&D Program of China(2013AA102901)the Special Fund for Agro-scientific Research in the Public Interest,China(201203077)
文摘The improvement of soil productivity depends on a rational input of water and nutrients, optimal field management, and the increase of basic soil productivity（BSP）. In this study, BSP is defined as the productive capacity of a farmland soil with its own physical and chemical properties for a specific crop season under local field management. Based on 19-yr data of the long-term agronomic experiments（1989–2008） on a fluvo-aquic soil in Zhengzhou, Henan Province, China, the decision support system for agrotechnology transfer（DSSAT ver. 4.0） crop growth model was used to simulate yields by BSP of winter wheat（Triticum aestivium L.） and summer maize（Zea mays L.） to examine the relationship between BSP and soil organic carbon（SOC） under long-term fertilization. Five treatments were included：（1） no fertilization（control）,（2） nitrogen, phosphorus and potassium fertilizers（NPK）,（3） NPK plus manure（NPKM）,（4） 1.5 times of NPKM（1.5NPKM）, and（5） NPK plus straw（NPKS）. After 19 yr of treatments, the SOC stock increased 16.7, 44.2, 69.9, and 25.2% under the NPK, NPKM, 1.5NPKM, and NPKS, respectively, compared to the initial value. Among various nutrient factors affecting contribution percentage of BSP to winter wheat and summer maize, SOC was a major affecting factor for BSP in the fluvo-aquic soil. There were significant positive correlations between SOC stock and yields by BSP of winter wheat and summer maize（P〈0.01）, and yields by BSP of winter wheat and summer maize increased 154 and 132 kg ha^（–1） when SOC stock increased 1 t C ha^（–1）. Thus, increased SOC accumulation is a crucial way for increasing BSP in fluvo-aquic soil. The manure or straw combined application with chemical fertilizers significantly enhanced BSP compared to the application of chemical fertilizers alone.
文摘Experiments including two in laboratory and one in greenhouse were carried out to study non- exchangeable magnesium release from fluvo-aquic soils sampled from Daxing and changping counties located in the suburbs of Beijing and Mg relative availability of the two soils to plants. In a batch experiment in laboratory the soils were incubated under wet conditions and alternation of dry and wet conditions and determined for amount of Mg released at the 4th, 8th and 12th week, respectively, after extraction of exchangeable Mg with 1 mol L-1 NH4Ac. The amount of Mg released from the soil of Daxing was higher than from the soil of Changping, which was in accordance with the fact that the soil of Daxing had higher contents of all forms of Mg than that of Changping. There was little difference in Mg release from soils between wet conditions and alternation of dry and wet conditions. About 1%~2% of the total non-exchangeable Mg might be released within 12 weeks of incubation, restoring about 30%~35% of the original soil exchangeable Mg. Results of the experiment on kinetics of Mg release from the soils through continuous extractions with 0.5 mol L-1 NH4Ac (pH 7.0) on a continuous flow apparatus in laboratory showed that Mg released rapidly in the beginning, decreased sharply with time and kept stable at 60 and 240 min for the soils of Changping and Daxing, respectively. Among the five mathematical models used to describe the kinetics of Mg release, the parabolic diffusion equation best fitted the cumulative Mg release, indicating that diffusion of Mg out of the soils might be the controlling process. The experiment of exhaustive cropping with 1 crop of tomato (Lycopersicon esculentum Mill.) followed by six crops of corn (Zea mays L.) in greenhouse showed that soil exchangeable Mg decreased remarkably with cropping. After three crops, the percentage of the total plant Mg uptake that came from soil non-exchangeable Mg was 29.5% for the soil from Changping and 35% for the soil from Daxing. About 50% of the total Mg uptake by plants in the six crops was believed to come from the soil non-exchangeable Mg form.
基金Supported by Soil Testing Formula Fertilization Program~~
文摘In order to verify organic carbon cycle under conservation tillage condition and the promotion mechanism of soil fertility and offer scientific theory support for the popularization and application of conservation tillage technological, the research investigated effects of different tillage treatments on the content of total organic car- bon, total nitrogen and different components of them in fluvo-aquic soil based on a long-term experiment site of conservation tillage. The research revealed effects of conservation tillage on the content of carbon, nitrogen in fluvo-aquic soil by study the distribution of soil total organic carbon, total nitrogen, dissolved organic carbon, dissolved organic nitrogen, microbial biomass carbon, liable carbon in different soil depth under different tillage treatments. The results showed that compared to con- ventional tillage treatment, contents of soil total organic carbon under intermittent tillage （tillage once every 2 or 4 years） and no-tillage treatment improved by 1.81%, 6.43%, 14.04%, respectively and contents of soil total nitrogen went up by 0.80%, 10.04%, 7.93%, respectively. Contents of soil total organic carbon and total nitrogen in 10-20 cm soil layer under no-tillage treatment were significantly lower than the other treatments. Under the condition of straw returned, intermittent tillage and no- tillage could significantly improve the content of soil dissolved organic carbon and ni- trogen in 0-5 cm and 5-10 cm soil. Compared to conventional tillage treatment, content of soil microbial biomass carbon and liable carbon in 0-5 cm soil under in- termittent tillage and no-tillage were improved in varying degrees. Content of soil microbial biomass carbon in 10-20 cm soil layer under no-tillage treatment was sig- nificantly lower than the other treatments. Straw returning had improved the content of soil total organic carbon, total nitrogen, dissolved organic carbon and other com- ponents of active organic carbon in varying degrees. In general, conservation tillage measures could increase carbon and nitrogen storage in 0-5 cm soil layer, the negative effects of ＂nutrients enrichment in surface＂ under no-tillage condition could be ameliorated by intermittent tillage.
基金Supported by Sub-project of National Key Research and Development Program of China in the 13thFive-Year Plan of China(2016YFD0300804-5)Special Fund for Agro-scientific Research in the Public Interest(201503106)Special Construction Project of"Overseas Taishan Scholar"
文摘This study was conducted to investigate the effects of long-term located fertilization on soil phosphorus,the changes of soil available phosphorus(OlsenP),the evolution of soil total phosphorus(TP)and the ratio change of Olsen-P to TP(PAC)by 33-year fertilization experiments in winter wheat-summer maize rotation system in Shandong fluvo-aquic soil.Eight treatments were designed as no fertilization(CK),nitrogen fertilizer(N),nitrogen and phosphate fertilizer(NP),nitrogen and potassium fertilizer(NK),phosphate and potassium fertilizer(PK),nitrogen-phosphate-potassium fertilizer(NPK),reduced NPK fertilizer(N(15)PK),and increased NPK fertilizer(N_(25)PK).Meanwhile,eight organic fertilizer-added treatments were designed based on the application of inorganic fertilizer the same as the above ones.The results showed that TP,Olsen-P and PAC of treatments added with organic fertilizer were higher than those without organic fertilizer,and those of the treatments applied with phosphate fertilizer were higher than those of no phosphate fertilizer.With the increase of years,soil P pool decreased due to crop absorption,nutrient loss and morphological transformation and other causes under the treatments of without and only phosphate fertilizer,while remained stable under the treatments added with organic fertilizer.The PAC values were generally lower in fluvo-aquic soil,and it could be improved by the application of organic fertilizer.On the whole,the application of chemical phosphate fertilizer combined with organic fertilizer could improve the phosphorus content in soil and ensure the supply of phosphorus nutrition.This study would provide scientific basis for fertilization management and soil fertility in fluvo-aquic soil.
基金Supported by Preliminary Special Foundation of Major State Basic Research Program(973)(2001CCB00800)Scientific and Technological Projects of Henan Province(072102170004)Key Public Welfare Research Project in Henan Province(081100911500)~~
文摘[Objective] The research aimed to study the effects of fertilization on soil remediation.[Method]Pot fertilizer tests were conducted to remedy the soils which had off-balanced in nutrients resulted by long-term unreasonable fertilization.[Result]The results showed that applying NPK fertilizers with manure was the best method to restore the soil nutrients and increase soil fertility and crop yield;NPK and NP fertilizers could balance soil fertility and increase crop yields,the effects were the same and next to MNPK.Phosphate and nitrogen respectively had the similar restoring effect with NPK fertilizers on soil from long-term NK and PK treatments.[Conclusion]Crops in soil with long-term applying NPK fertilizers had strong dependence on fertilizers.The yields of corn and wheat decreased by 78.6% and 52.8% respectively after stopping applying fertilizers.Meanwhile,The yields of corn and wheat increased by 112% and 182% respectively after stopping applying fertilizers in NK treatment as well as 15.1% and 59% in PK treatment.Manure had strong and last effect on increasing yield.
基金supported by the National Natural Science Foundation of China (41471249)the Special Scientific Research Fund of Agricultural Public Welfare Profession of China (201503120)
文摘The concentration of soil Olsen-P is rapidly increasing in many parts of China, where P budget(P input minus P output) is the main factor influencing soil Olsen-P. Understanding the relationship between soil Olsen-P and P budget is useful in estimating soil Olsen-P content and conducting P management strategies. To address this, a long-term experiment(1991–2011) was performed on a fluvo-aquic soil in Beijing, China, where seven fertilization treatments were used to study the response of soil Olsen-P to P budget. The results showed that the relationship between the decrease in soil Olsen-P and P deficit could be simulated by a simple linear model. In treatments without P fertilization(CK, N, and NK), soil Olsen-P decreased by 2.4, 1.9, and 1.4 mg kg^(–1) for every 100 kg ha^(–1) of P deficit, respectively. Under conditions of P addition, the relationship between the increase in soil Olsen-P and P surplus could be divided into two stages. When P surplus was lower than the range of 729–884 kg ha^(–1), soil Olsen-P fluctuated over the course of the experimental period with chemical fertilizers(NP and NPK), and increased by 5.0 and 2.0 mg kg^(–1), respectively, when treated with chemical fertilizers combined with manure(NPKM and 1.5 NPKM) for every 100 kg ha^(–1) of P surplus. When P surplus was higher than the range of 729–884 kg ha^(–1), soil Olsen-P increased by 49.0 and 37.0 mg kg^(–1) in NPKM and 1.5 NPKM treatments, respectively, for every 100 kg ha^(–1) P surplus. The relationship between the increase in soil Olsen-P and P surplus could be simulated by two-segment linear models. The cumulative P budget at the turning point was defined as the "storage threshold" of a fluvo-aquic soil in Beijing, and the storage thresholds under NPKM and 1.5 NPKM were 729 and 884 kg ha^(–1)P for more adsorption sites. According to the critical soil P values(CPVs) and the relationship between soil Olsen-P and P budget, the quantity of P fertilizers for winter wheat could be increased and that of summer maize could be decreased based on the results of treatments in chemical fertilization. Additionally, when chemical fertilizers are combined with manures(NPKM and 1.5 NPKM), it could take approximately 9–11 years for soil Olsen-P to decrease to the critical soil P values of crops grown in the absence of P fertilizer.
基金supported by the China Agriculture Research System (CARS-25-C-11)the Special Fund for Agro-Scientific Research in the Public Interest, China (201203095)
文摘Organic manure application is an important measure for high yield and good quality vegetable production, whereas organic manure is also a main source of residual antibiotic in soils. A 3-yr experiment was conducted on a fluvo-aguic soil in Tianjin of northern China. The objective of this study was to investigate the effects of different fertilization patterns on yield of six-sea- son vegetables with celery and tomato rotation, and dynamic change of tetracyclines residues in the soil during the sixth growing season （tomato season）. The field experiment comprised six treatments depending on the proportion of nitrogen of each type of fertilizer： 4/4 CN （CN, nitrogen in chemical fertilizer）, 3/4 CN＋1/4 MN （MN, nitrogen in pig manure）, 2/4 CN＋2/4 MN, 1/4 CN＋3/4 MN, 2/4 CN＋1/4 MN＋I/4 SN （SN, nitrogen in corn straw）, and CF （conventional fertilization, the amounts of nitrogen application were 943 and 912 kg N ha-1 for celery and tomato season, respectively）. In addition to CF treatment, the amount of nitrogen application in other treatments was greatly reduced and equal （450 and 450 kg N ha-1 for celery and tomato season, respectively）. Results showed that the combined application of 3/4 CN＋1/4 MN achieved the highest yield and economic benefit in the first four seasons, but addition of straw （2/4 CN＋1/4 MN＋I/4 SN treatment） performed better in the subsequent two seasons, and the average yields of 2/4 CN＋1/4 MN＋I/4 SN treatment were respectively higher by 9.9 and 12.8% than those of 4/4 CN treatment, and by 5.6 and 10.5% than those of CF treatment. The residual chlortet- racycline （CTC） in manure-amended soil for three consecutive years increased along with the increase of applied amount of pig manure. Under the same amount of pig manure application, content of CTC in straw-amended soil was obviously decreased compared with no straw-amended soil （3/4 CN＋1/4 MN treatment）, and averagely decreased by 41.9% for four sampling periods in the sixth season. Addition of crop straw facilitated the degradation of CTC in manure-amended soil. As a whole, the conventional fertilization was not the desirable pattern based on yield, economic benefit and environment, the optimal fertilization pattern with the highest yield and profit and the least soil chlortetracycline residue was the treatment of 2/4 CN＋1/4 MN＋I/4 SN under this experimental condition.
基金Project supported by the National Natural Science Foundation of China (Nos. 40071053 and 40078055).
文摘Soil P status, inorganic P fractions, and P sorption properties were studiedusing sandy fluvo-aquic horticultural soils, which are high in organic matter content for vegetableproduction in comparison with a soil used for grain crop production in Zhengzhou, Henan Province,China P fractions, Olsen-P, and OM were determined at different depths in the soil profile andsorption isotherm experiments were performed Most P in excess of plant requirements accumulated inthe topsoil and decreased with soildepth. Total P, inorganic P, and OM concentrations increased withcontinued horticultural use Olsen-P concentrations in the 0-20 cm depth of horticultural soils were9 to 25 times higher than those of the grain crop soil. A linear transformation of the Langmuirequation showed that the P adsorption maximum (491.3 mg P kg^(-1)) and the maximum phosphatebuffering capacity (162.1 L kg^(-1)) for 80--100 cm were greater in the grain crop soil than thehorticultural soils. Thus, the most immediate concern with excess P were in areas where heavy Pfertilizer was used for vegetable crops and where soil P sorption capacities were low due to sandysoils and high organic matter content.
基金supported by the National Science Foundation of China(49391600)the Society Commonweal Fund(2001DIA20024).
文摘The K+ adsorption kinetics of fluvo-aquic soil and cinnamon soil under different temperatureswere studied. The results showed: 1) The first order equations were the most suitable forfitting the adsorption under various temperature levels with constant K+ concentration indisplacing fluid. With temperature increasing, the fitness of Elovich equation increased,while those of power equation and parabolic diffusion equation decreased; 2)the apparentadsorption rate constant ka and the product of ka multiplied by the apparent equilibriumadsorption qincreased when temperature increased, while the apparent equilibrium adsorptionqreduced; 3)temperature influenced hardly the reaction order, the order of concentrationand adsorpton site were always 1 under various temperatures, if they were taken intoaccount simultaneously, the adsorption should be a two-order reaction process; 4)theGibbs free energy change △G of potassium adsorption were negative, ranged from -4444.56to -2450.63Jmol-1,and increased with temperature increasing, while enthalpy change △H,entropy change △S, apparent adsorption activation Ea, adsorption activation energy E1and desorption activation energy E2 were temperature-independent; 5)the adsorption wasspontaneous process with heat releasing and entropy dropping, fluvo-aquic soil releasedmore heat than cinnamon soil.
基金This work was funded by the National Natural Science Founda-tion of China(42007076)the Shandong Provincial Natural Science Foundation(ZR2020QD116 and ZR2019BD032)the China Postdoctoral Science Foundation(2020T130387 and 2019M652448).
文摘Differently sized soil aggregates,with non-uniform distribution of space and nutrients,provide spatially heterogeneous microenvironments for microorganisms and are important for controlling microbial community ecology and biogeochemistry in soils.Here,we investigated the prokaryotic communities within different aggregate-size fractions:macroaggregate(>0.25 mm),microaggre-gate(0.053–0.25 mm)and silt+clay(<0.053 mm).These were isolated from fluvo-aquic soils under 39-year fertilization strategies:no fertilizer(CK),chemical fertilizer(NPK),manure fertilizer(M),and combination of manure and chemical fertilizers(MNPK).The results showed that the proportion of macroaggregate,soil aggregate-associated organic carbon(SOC)content and aggregate stability were all significantly increased by both manure and chemical fertilizations.Organic fertilizations(M and MNPK)more effectively boosted formation and stability of macroaggregates and enhanced SOC concentration than NPK.The distribution patterns of microorganisms in aggregates were primarily shaped by fertilization and aggregate size.They explained 76.9%of the variance in bacterial community compositions.Fertilizations,especially with organic fertilizers primarily transitioned bacterial communities from slow-growing oligotrophic groups(e.g.,Chloroflexi)dominance to fast-growing copiotrophic groups(e.g.,Proteobacteria and Bacteroidetes)dominance across all aggregate sizes.Macroaggregates possessed a more stable bacterial community and efficiency of resource transfer,while smaller aggregates increased antagonism and weakened mutualism among bacterial communities.Overall,combination of manure and chemical fertilizers was crucial for increasing SOC content and aggregation,leading to a clear shift in bacterial community structures at aggregate scale.
基金supported by National Key R&D Program of China (2022YFD1900104)。
文摘To maintain soil quality under long-term saline water irrigation,the influence of manure on soil physical properties was examined.Long-term saline irrigation has been conducted from 2015 to 2024 at the Nanpi Eco-Agricultural Experimental Station of Chinese Academy Sciences in the Low Plain of the North China Plain,comprising four irrigation treatments:irrigation once at the jointing stage for winter wheat with irrigation water containing salt at fresh water,3,4 and 5 g·L^(–1),and maize irrigation at sowing using fresh water.Manure application was conducted under all irrigation treatments,with treatments without manure application used as controls.The results showed that under long-term irrigation with saline water,the application of manure increased the soil organic matter content,exchangeable potassium,available phosphorus,and total nitrogen content in the 0–20 cm soil layer by 46.8%,117.0%,75.7%,and 45.5%,respectively,compared to treatments without manure application.The application of manure reduced soil bulk density.It also increased the proportion of water-stable aggregates and the abundance of bacteria,fungi,and actinomycetes in the tillage soil layer compared to the controls.Because of the salt contained in the manure,the application of manure had dual effects on soil salt content.During the winter wheat season,manure application increased soil salt content.The salt content was significantly reduced during the summer maize season,owing to the strong salt-leaching effects under manure application,resulting in a smaller difference in salt content between the manure and non-manure treatments.During the summer rainfall season,improvements in soil structure under manure application increased the soil desalination rate for the 1 m top soil layer.The desalination rate for 0–40 cm and 40–100 cm was averagely by 39.1%and 18.9%higher,respectively,under manure application as compared with that under the nomanure treatments.The yield of winter wheat under manure application was 0.12%lower than that of the control,owing to the higher salt content during the winter wheat season.In contrast,the yield of summer maize improved by 3.9%under manure application,owing to the increased soil nutrient content and effective salt leaching.The results of this study indicated that manure application helped maintain the soil physical structure,which is important for the long-term use of saline water.In practice,using manure with a low salt content is suggested to reduce the adverse effects of saline water irrigation on soil properties and achieve sustainable saline water use.
文摘[Objective]Vegetation restoration is an effective strategy for ecological improvement;however,inappropriate vegetation establishment can induce soil desiccation,thereby threatening ecosystem stability.Therefore,elucidating the global response patterns of soil moisture to vegetation restoration and identifying research hotspots are critical for guiding ecological construction in arid regions.[Methods]We reviewed 6,152 articles concerning soil moisture and vegetation retrieved from the Web of Science platform.Using VOSviewer,we conducted analyses of keyword co-occurrence,publication trends,and research hotspots to systematically delineate the evolving trends in this field.[Results]The results indicate a significant increasing trend in the number of publications since 2000.Global research keywords are categorized into seven clusters,including vegetation,soil moisture,rainfall-erosion-infiltration,spatial heterogeneity,and climate change.In terms of highly cited papers in 2024,China and the United States maintain a significant lead.Global research demonstrates a strong dependency on typical regional geographical features(such as climate types and topography),exhibiting differentiated research focuses.Furthermore,studies extend beyond soil moisture itself to deeply couple with ecological processes such as vegetation restoration,soil respiration,carbon cycling,and hydrothermal conditions.[Conclusions]The long-term ecological effects of afforestation in arid regions remain unclear,and empirical data from key regions highlight the current urgency.Future research should integrate climate change dynamics,innovate monitoring methodologies,and deepen the understanding of regional differentiation to provide scientific support for the adaptive management of vegetation in arid regions.
文摘39 soil samples surrounding a lead-zinc mining area in Guangxi were collected,and the contents of Pb,Hg,Cd,Cr,As,Cu,Zn,and Ni were determined to investigate the pollution characteristics and sources of heavy metals.ArcGIS inverse distance weight difference method was used to analyze the characteristics of pollution distribution,and single-factor pollution index,Nemerow comprehensive pollution index,ground accumulation index,and potential ecological risk index were selected to evaluate the characteristics of heavy metal pollution.Based on correlation analysis,the absolute principal component-multiple linear regression(APCS-MLR)and positive definite matrix factorization(PMF)models were used to analyze the sources of soil heavy metals.The results showed that the average concentrations of all eight heavy metals exceeded both national and Guangxi soil background values.Hg,Cd,and Zn exhibited high variation(greater than 0.5),indicating significant external disturbances,and their spatial distribution was closely related to mining activity locations.The single-factor pollution index evaluation indicated varying degrees of pollution risk for Cd,Zn,and As,with Cd and Zn being the most severe pollutants,as 69.23%and 30.77%of the samples fell into the moderate pollution or higher category.The geoaccumulation index analysis ranked the mean pollution levels of the eight elements as follows:Zn>Cd>Ni>Pb>Cu>Cr>Hg>As,with Cd and Zn showing the most severe contamination,and 51.28%of the samples exhibiting moderate or higher pollution levels.The Nemerow comprehensive pollution index evaluation showed that 74.35%of soil samples were classified as moderate to heavy pollution.The potential ecological risk index assessment indicated significant ecological risks posed by Cd and Zn,with 82.05%and 5.12%of the samples classified as causing strong to extreme ecological risks,respectively.The source apportionment analysis revealed minor differences between the two models.The APCS-MLR model identified three pollution sources and their contribution rates:anthropogenic mining sources(31.13%),parent material sources(40.38%),and unidentified sources(28.49%).The PMF model identified three pollution sources with contribution rates of anthropogenic mining sources(26.10%),parent material sources(46.96%),and a combined traffic and agricultural source(26.61%).Pb,Hg,Cd,and Zn mainly originated from mining activities;Cr,As,and Ni were primarily derived from the parent material,while Cu was predominantly attributed to traffic and agricultural sources.These findings provide a scientific basis for the prevention and control of heavy metal pollution in mining areas.
基金supported by the National Key Research and Development Program of China(2023YFD2200403)National Natural Science Foundation of China(No.32260382)the Natural Science Foundation of Guangxi(2025GXNSFBA069250).
文摘Soil respiration is the key process driving CO_(2) exchange between forest soils and the atmosphere and regulated by soil organic carbon(SOC)characteristics and extracellular enzyme activities.However,the direction and magnitude of the effects of stand density on labile SOC fractions,extracellular enzymes,and soil respiration across plantation ages remain unclear.We constructed enhanced soil respiration models using heterogeneous soil data under density regulation to better characterize soil processes.Study plots encompassing stand-density gradients were implemented in Larix principis-rupprechtii plantations spanning three age-class strata.During the growing season,systematic measurements were conducted on soil respiration rates,labile organic carbon fractions,and extracellular enzyme activities.A process-driven soil respiration model was developed by integrating nonlinear mixed-effects modeling frameworks with measured data.The moderate density stands showed increases in soil respiration(Rs),microbial biomass carbon(MBC),light fraction organic carbon(LFOC),β-1,4-glucosidase(BGC),andβ-N-acetyl glycosaminidase+leucine aminopeptidase(NAG+LAP).In 36a and 48a stands,the moderate-density stands NAG+LAP had a~35%increase compared to other density levels,while readily oxidized carbon(ROC)concentrations showed a significant~30%-50%reduction.All labile organic carbon components were stable with age,so that soil microorganisms were promoted to acquire C,N,and P.Temperature,moisture,MBC,BGC,and NAG+LAP were essential factors that affected soil respiration.Stand density has important impacts on soil respiration as it regulates the soil organic carbon and activities of extracellular enzymes.The roles of temperature,microbial biomass carbon,soil organic carbon and dissolved organic carbon are complex and directly affect autotrophic and heterotrophic respiration and regulate soil respiration by influencing microbial C and N acquisition.A mixed-effects model with nested stand density and age mathematically optimized the soil respiration model,enabling enhanced characterization of covariation patterns of soil respiration with related soil carbon pool variables.
基金supported by the National Natural Science Foundation of China(Nos.42388101,82403271)Natural Science Foundation of Ningbo Municipality(No.2024J420)Ningbo Top Talent Project(No.215-432094250).
文摘Panax species are globally recognized for their high medicinal and economic value,yet large-scale cultivation is constrained by high production costs,progressive soil acidification,and persistent soil-borne diseases.Although various soil improvement strategies have been tested,a comprehensive synthesis of their comparative effectiveness has been lacking.Here,we conducted a meta-analysis of 1381 observations from 54 independent studies to evaluate the effects of conventional fertilizers,microbial fertilizers,organic amendments,and inorganic amendments on Panax cultivation.Our results demonstrate that microbial fertilizers,organic amendments,and inorganic amendments significantly increased soil pH,thereby ameliorating soil acidification.Among them,organic amendments significantly enhanced the content of soil organic carbon,available nitrogen,and available phosphorus,alongside a notable increase in microbial diversity(Chao1 and ACE indices,which increased by 9%and 17%,respectively).Moreover,our analysis revealed that while microbial fertilizers,organic amendments,and inorganic amendments(except conventional fertilizers)reduced the disease index of Panax plants,organic amendments demonstrated absolute superiority in promoting plant height,root dry weight,root fresh weight,and root length.By quantitatively integrating multi-source evidence,this study provides novel mechanistic insights and practical recommendations that extend beyond local practices,offering guidance for sustainable ginseng cultivation and broader medicinal plant production systems worldwide.
基金supported by the National Natural Science Foundation of China (Grant No.52308352)the Jiangxi Provincial Natural Science Foundation (Grant Nos.20242BAB25299,20232BAB214082)。
文摘One of the research hotspots in geotechnical engineering is the solidification of problematic soil foundations. However, the traditional materials, such as Portland cement, lime, and various types of chemical solutions, typically cause CO_(2) emissions and environmental pollution. Geopolymer is a newly proposed method for soil solidification, offering an environmentally friendly and effective solution. Given that soils typically consist of diverse compositions, an optimal soil stabilization technique should be versatile enough to be applied across various soil types, ensuring consistent strength outcomes with minimal variations among different soil compositions. In this study, three commonly used geopolymers(fly ash, ground granulated blast-furnace slag, and metakaolin) were utilized to stabilize silt, loess, silica sand, calcareous sand, and gravel, representing a diverse range of soils. The mechanical properties and microstructures of both geopolymers and geopolymerstabilized soils were analyzed. The findings indicated that the strength of stabilized coarse cohesionless soils was primarily influenced by the mechanical properties of the geopolymers themselves, with minimal impact from the inherent properties of the soil. However, the effectiveness of stabilizing cohesive soil may show significant discrepancies compared to the mechanical properties of geopolymer materials when certain types of geopolymers, like metakaolin, are employed. Higher strength is typically achieved through a denser structure(with fewer pores) and the presence of products with a higher degree of polymerization. Additionally, ground granulated blast-furnace slag exhibited excellent stability and superior strength when compared to other types of geopolymers. The present research establishes a basis for selecting geopolymers to stabilize a range of soils, including those with non-uniform compositions and diverse components.
基金supported financially by the National Key Research&Development Program of China(2021YFD1700200)the National Natural Science Foundation of China(32402686)+3 种基金the Earmarked Fund for China Agriculture Research System(CARS-22)the Fundamental Research Funds for Central Non-profit Scientific Institution,China(1610132022013)the Science and Technology Innovation Project of Chinese Academy of Agricultural Sciencesthe China National Crop Germplasm Resources Platform for Green Manure(NICGR-2024-19)。
文摘Green manuring is essential for improving soil quality and nutrient uptake.With the gradual depletion of phosphorus(P)resources,more attention is being paid to the role of green manures in cultivation systems,such as maize-green manure intercropping,to find possible pathways for enhancing soil P utilization.A maize-green manure intercropping experiment was started in 2009 to investigate the effects and mechanisms for enhancing P uptake and yield in maize.Three species of green manures(hairy vetch(HV),needle leaf pea(NP),sweet pea(SP))and a sole maize treatment(CK)were used,resulting in four treatments(CK,HVT,NPT,and SPT)in the experiment.During 2020-2023,the intercropping treatments enhanced maize yields in 2020 and 2021,particularly in HVT with increases of 13.7%(1.96 t ha^(-1))and 13.0%(2.13 t ha^(-1))compared with CK,respectively.Grain P accumulation of maize was significantly higher in the intercropping treatments than CK in 2020,2021,and 2023,and with an average increase of 10.6%over the four years(5.2% for NPT,10.8% for SPT and 15.9% for HVT)compared with CK.Intercropping promoted maize growth with a greater root length density and a higher organic acid release rate.HVT changed the soil properties more dramatically than the other treatments,with increases in the acid phosphatase and alkaline phosphatase activities of 29.8 and 38.5%,respectively,in the topsoil(0-15 cm),while the soil p H was reduced by 0.37 units compared to CK(p H=8.44).Intercropping treatments facilitated the conversion of non-labile P to mod-labile P and stimulated the growth of soil bacteria in the topsoil.Compared with CK,the relative abundance of Gemmatimonadota,known for accumulating polyphosphate,and Actinobacteriota,a prominent source of bioactive compounds,increased significantly in the intercropping treatments,especially in HVT and SPT.A PLS-PM analysis showed that intercropping promoted soil P mobilization and the enrichment of beneficial bacteria by regulating maize root morphology and physiology.Our results highlight that maize-green manure intercropping optimizes root traits,soil properties and bacterial composition,which contribute to greater maize P uptake and yield,providing an effective strategy for sustainable crop production.
基金funded by the Yunnan Provincial Key Programs for Basic Research Project,China(202301AS070087)the Yunnan Provincial R&D Program,China(202405AF140014 and 202302AO370015)the National Natural Science Foundation of China(42307058).
文摘Soil organic carbon(SOC)dynamics significantly influence ecosystem carbon source-sink balance,particularly in agroecosystems.However,uncertainty remains regarding optimal land use types for maximizing farmland carbon storage across different soil types,and identifying effective land management practices for enhanced carbon accumulation is essential for reducing agricultural emissions and strengthening carbon sinks.This study examined SOC variations in eastern Yunnan’s subtropical highlands(2,132 sites),analyzing topsoil(0–20 cm)across five land uses(dryland,irrigated land,forestland,grassland and plantation)of five soil types(red,yellow,yellowbrown,brown,purple).The investigation explored relationships between SOC and edaphic factors(26 elements)to determine SOC influencing factors.The study area demonstrated a mean SOC content of 27.78 g kg^(–1),with distinct spatial heterogeneity characterized by lower values in the southwestern sector and higher concentrations in the northeastern region.Brown soils displayed the highest SOC content(P<0.05),followed by yellow-brown then red,yellow,and purple soils.Irrigation significantly enhanced SOC storage,particularly in brown soils where irrigated land contained 2.2-,2.4-,and 1.6-times higher SOC than forestland,grassland,and dryland,respectively.Similar irrigation benefits occurred in purple,yellow,and yellow-brown soils,indicating moisture limitation as the primary SOC constraint.Notably,SOC exhibited strong positive correlations with nitrogen,sulfur,and selenium.Nitrogen fertilization demonstrated dual benefits:enhancing SOC sequestration and promoting Se enrichment in crops,potentially supporting specialty agriculture.Although land use impacts on SOC varied across soil types(P>0.05),irrigation consistently emerged as the optimal management for carbon sink enhancement.These findings suggest that targeted water management could effectively reduce farmland carbon emissions in moisture-limited subtropical highlands.Strategic nitrogen application offers co-benefits for soil fertility and selenium biofortification,providing practical pathways for climate-smart agriculture in similar ecoregions.
