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
State Administration for Market Regulation and National Standardization Administration of China have approved the following 758 voluntary national standards and 6 voluntary national standards with amendment.
Long-term manure application has the potential to alleviate soil acidification, and increase carbon sequestration and nutrient availability, thus improving cropland fertility. However, the mechanisms behind greenhouse...Long-term manure application has the potential to alleviate soil acidification, and increase carbon sequestration and nutrient availability, thus improving cropland fertility. However, the mechanisms behind greenhouse gas N_(2)O emissions from acidic soil mediated by long-term manure application remain poorly understood. Herein, we investigated N_(2)O emission and its linkage with gross N mineralization and nitrification rates, as well as nitrifying and denitrifying microbes in an acidic upland soil subjected to 36-year fertilization treatments, including an unfertilized control(CK), inorganic fertilizer(F), 2× rate of inorganic fertilizer(2F), manure(M), and the combination of inorganic fertilizer and manure(FM) treatments. Compared to the CK treatment(1.34 μg N kg^(-1) d^(-1)), fertilization strongly increased N_(2)O emissions by 34-fold on average, with more pronounced increases in the manure-amendment(10.6-169 μg N kg^(-1) d^(-1)) than those in the inorganic fertilizer treatments(3.26-5.51 μg N kg^(-1) d^(-1)). The manure amendment-stimulated N_(2)O emissions were highly associated with increased soil pH, mean weight diameter of soil aggregates, substrate availability(e.g., particulate organic carbon, NO_(3)^(-)and available phosphorus), gross N mineralization rates, denitrifier abundances and the(nirK+nirS)/nosZ ratio. These findings suggest that the increased N_(2)O emissions primarily resulted from alleviated acidification, increased substrate availability and improved soil structure, thus enhancing microbial N mineralization and favoring N_(2)O^(-)producing denitrifiers over N_(2)O consumers. Moreover, ammonia-oxidizing bacteria(AOB) rather than ammonia-oxidizing archaea(AOA) positively correlated with soil NO_(3)^(-)concentration and N_(2)O emissions, indicating that nitrification indirectly contributed to N_(2)O production by supplying NO_(3)^(-)for denitrification. Collectively, manure amendment potentially stimulates N_(2)O emissions, primarily resulting from alleviated soil acidification and increased substrate availability, thus enhancing N mineralization and denitrifier-mediated N_(2)O production. Our findings suggest that consideration should be given to the greenhouse gas budgets of agricultural ecosystems when applying manure for managing the pH and fertility of acidic soils.展开更多
An amendment to the Electoral Law of the National People’s Congress and Local People’s Congresses of the People’s Republic of China providing equal legislative representation to rural and urban people was ratified ...An amendment to the Electoral Law of the National People’s Congress and Local People’s Congresses of the People’s Republic of China providing equal legislative representation to rural and urban people was ratified at the closing meeting of the Third Session of the 1 1th展开更多
Organic material combined with inorganic fertilizer has been shown to greatly improve crop yield and maintain soil fertility globally. However, it remains unclear if crop yield and soil fertility can be sustained in t...Organic material combined with inorganic fertilizer has been shown to greatly improve crop yield and maintain soil fertility globally. However, it remains unclear if crop yield and soil fertility can be sustained in the long term under the combined application of organic and inorganic fertilizers. Three long-term field trials were conducted to investigate the effects of organic amendments on the grain sustainable yield index(SYI), soil fertility index(SFI)and nutrient balance in maize–wheat cropping systems of central and southern China during 1991–2019. Five treatments were included in the trials: 1) no fertilization(control);2) balanced mineral fertilization(NPK);3) NPK plus manure(NPKM);4) high dose of NPK plus manure(1.5NPKM);and 5) NPK plus crop straw(NPKS). Over time, the grain yields of wheat and maize showed an increasing trend in all four fertilization treatments at the Yangling(YL) and Zhengzhou(ZZ) locations, while they declined at Qiyang(QY). The grain yield in the NPKM and 1.5NPKM treatments gradually exceeded that of the NPK and NPKS treatments at the QY site. The largest SYI was recorded in the NPKM treatment across the three sites, suggesting that inorganic fertilizer combined with manure can effectively improve crop yield sustainability. Higher SYI values were recorded at the YL and ZZ sites than at the QY site, possibly because the soil was more acid at QY. The key factors affecting grain yield were soil available phosphorus(AP) and available potassium(AK) at the YL and ZZ sites, and pH and AP at the QY site.All fertilization treatments resulted in soil N and P surpluses at the three sites, but soil K surpluses were recorded only at the QY site. The SFI was greater in the 1.5NPKM, NPKM and NPKS treatments than in the NPK treatment by 13.3–40.0 and 16.4–63.6% at the YL and ZZ sites, respectively, and was significantly higher in the NPKM and 1.5NPKM treatments than in the NPK and NPKS treatments at the QY site. A significant, positive linear relationship was found between SFI and crop yield, and SYI and nutrient balance, indicating that grain yield and its sustainability significantly increased with increasing soil fertility. The apparent N, P and K balances positively affected SFI.This study suggests that the appropriate amount of manure mixed with mineral NPK fertilizer is beneficial to the development of sustainable agriculture, which effectively increases the crop yield and yield sustainability by improving soil fertility.展开更多
Identification of the most appropriate chemically extractable pool for evaluating Cd and Pb availability remains elusive,hindering accurate assessment on environmental risks and effectiveness of remediation strategies...Identification of the most appropriate chemically extractable pool for evaluating Cd and Pb availability remains elusive,hindering accurate assessment on environmental risks and effectiveness of remediation strategies.This study evaluated the feasibility of European Community Bureau of Reference(BCR)sequential extraction,Ca(NO_(3))_(2)extraction,and water extraction on assessing Cd and Pb availability in agricultural soil amended with slaked lime,magnesium hydroxide,corn stover biochar,and calcium dihydrogen phosphate.Moreover,the enriched isotope tracing technique(^(112)Cd and^(206)Pb)was employed to evaluate the aging process of newly introduced Cd and Pbwithin 56 days’incubation.Results demonstrated that extractable pools by BCR and Ca(NO_(3))_(2)extraction were little impacted by amendments and showed little correlation with soil pH.This is notable because soil pH is closely linked to metal availability,indicating these extraction methods may not adequately reflect metal availability.Conversely,water-soluble concentrations of Cd and Pb were markedly influenced by amendments and exhibited strong correlations with pH(Pearson’s r:-0.908 to-0.825,P<0.001),suggesting water extraction as a more sensitive approach.Furthermore,newly introduced metals underwent a more evident aging process as demonstrated by acid-soluble and water-soluble pools.Additionally,water-soluble concentrations of essential metals were impacted by soil amendments,raising caution on their potential effects on plant growth.These findings suggest water extraction as a promising and attractive method to evaluate Cd and Pb availability,which will help provide assessment guidance for environmental risks caused by heavy metals and develop efficient remediation strategies.展开更多
Rubble deposits with a high concentration of rock debris were created after the powerful earthquakes in Jiuzhaigou.Because of the restricted soil resources,water leaks,and nutrient deficits,these deposits pose serious...Rubble deposits with a high concentration of rock debris were created after the powerful earthquakes in Jiuzhaigou.Because of the restricted soil resources,water leaks,and nutrient deficits,these deposits pose serious obstacles for vegetation regeneration.The purpose of this study was to investigate the main mechanisms controlling soil water retention and evaluate the effects of different amendments on the hydraulic characteristics and water-holding capacity of collapsed rubble soils.Finegrained soil,forest humus,crushed straw,and organic components that retain water were added to the altered soils to study the pore structure images and soil-water characteristic curves.Comparing understory humus to other supplements,the results showed a considerable increase in the soil's saturated and wilting water content.The saturated water content and wilting water content rose by 17.9%and 4.3%,respectively,when the percentage of understory soil reached 30%.Additionally,the enhanced soil's microporosity and total pore volume increased by 45.33%and 11.27%,respectively,according to nuclear magnetic imaging.It was shown that while clay particles and organic matter improved the soil's ability to adsorb water,they also increased the soil's total capacity to store water.Fine particulate matter did this by decreasing macropores and increasing capillary pores.These results offer an essential starting point for creating strategies for soil repair that would encourage the restoration of plants on slopes that have been damaged.展开更多
Despite the promising outcomes observed in individual applications of biochar and polyvinyl alcohol(PVA)in soil,the impact of their combined usage remains inadequately understood.This study systematically explores the...Despite the promising outcomes observed in individual applications of biochar and polyvinyl alcohol(PVA)in soil,the impact of their combined usage remains inadequately understood.This study systematically explores the effects of concurrent biochar and PVA application on key soil parameters,including pH,water-holding capacity(WHC),and dynamic moisture content(MC),and the photosynthetic resilience and growth of the cyanobacterium Microcoleus vaginatus in a desert soil.Biochars,generated at different pyrolysis temperatures(300-600℃),were applied to the soil at varying rates(1%-6%),while PVA was introduced at a mass percentage of 0.05%.The photosynthetic resilience and biomass accumulation of M.vaginatus in different treatments were examined every 7 d during the 28-d exposure to dry conditions after 60-d water supply.The combined application of biochar and PVA resulted in a reduction of soil pH,coupled with significant improvements in WHC and dynamic MC.Moreover,this combined approach exhibited superior effects on the photosynthetic resilience and crust thickness(0.9-3.5 mm)of M.vaginatus compared to the application of biochar and PVA in isolation.Incremental increase in biochar application rate from 0% to 6% demonstrated a notable enhancement in the chlorophyll a content of M.vaginatus.Cyanobacterial crust thickness and exopolysaccharide content exhibited positive correlations with biochar application rate.Thus,combined application of biochar and PVA is cost-effective for enhancing soil properties and cyanobacterial biomass,which is of significance for combating desertification.展开更多
Biochar has emerged as a promising tool for enhancing vineyard sustainability by improving soil properties and mitigating climate change impacts.This review highlights key findings on biochar’s role in viticulture,fo...Biochar has emerged as a promising tool for enhancing vineyard sustainability by improving soil properties and mitigating climate change impacts.This review highlights key findings on biochar’s role in viticulture,focusing on its effects on soil fertility,water retention,and plant physiology.Field and pot studies demonstrate that biochar amendments enhance soil structure,increase cation exchange capacity(CEC),and promote water availability,leading to improved drought resistance in grapevines.However,the impacts on grape yield,physiology,and quality remain inconclusive,with some studies reporting benefits while others show neutral effects.Future research should focus on optimizing biochar application rates,understanding its interactions with soil microbiota,and assessing long-term impacts on grape production and wine quality.Additionally,addressing potential risks,such as heavy metal contamination and changes in microbial communities,is crucial for its safe and effective use.This review aims to supply a comprehensive assessment of our knowledge about the incidence and consequences of biochar on soil,including its potential use in soil remediation and concerns regarding its possible negative impacts,with a focus on its effects on vine physiology and grape production.展开更多
Traditional studies of microbial succession under iron-carbon composite(Fe-C)amendment application have focused on the entire microbial community,with limited attention to the responses and ecological roles of abundan...Traditional studies of microbial succession under iron-carbon composite(Fe-C)amendment application have focused on the entire microbial community,with limited attention to the responses and ecological roles of abundant or rare taxa.Herein,a 90-day microcosm incubation was conducted to investigate the effects of three Fe-C amendments,including Fe_(3)O_(4)-modified biochar(FeC-B),ferrihydrite-natural humic acid(FeC-N),and ferrihydrite-synthetic humic-like acid(FeC-S),on distribution patterns,assembly processes,and ecological functions of both abundant and rare subcommunities.Our results showed that Fe-C amendments significantly affected theα-diversity of rare taxa,particularly under FeC-B treatment,with minimal impact on abundant taxa.Fe-C amendments also reshaped the community structures of both groups.Rare taxa,representing 63.9%of Operational Taxonomic Unit(OTU)richness but only 1.6%of total abundance,played a key role in community diversity and were more susceptible to Fe-C amendments.Certain rare taxa transitioned to abundant status,demonstrating their potential as a microbial seed bank.Abundant taxa were positioned more centrally within the networks,and Fe-C applications promoted cooperative interactions between abundant and rare species.Deterministic processes dominated the assembly of the rare subcommunity,while stochastic processes primarily influenced the abundant bacterial community.Fe-C amendments reduced community differentiation among rare taxa while increasing variability among abundant groups.Functional diversity of rare groups surpassed that of abundant groups,with notable enhancement in nitrogen cycling-related genes under Fe-C treatments.This study highlights the complementary roles of abundant and rare taxa in soil remediation,providing insights for optimizing remediation strategies.展开更多
Organic amendments(OM)can profoundly affect soil nitrous oxide(N_(2)O)emissions via changing nitrogen(N)cycles.However,mechanistic insights into how nitrification inhibitors modulate the responses of soil N_(2)O emiss...Organic amendments(OM)can profoundly affect soil nitrous oxide(N_(2)O)emissions via changing nitrogen(N)cycles.However,mechanistic insights into how nitrification inhibitors modulate the responses of soil N_(2)O emissions to successive applications of OM are currently insufficient.In this study,we performed a laboratory experiment to examine N_(2)O emissions from a tropical vegetable soil subjected to six years of chemical fertilization(CF)and chemical fertilization combined with manure application(CFM)and evaluate the mitigation effectiveness of nitrification inhibitor dicyandiamide(DCD)under each management regime.Isotopocule mapping showed that bacterial nitrification and/or fungal denitrification accounted for 77.4%–88.5%of total N_(2)O production across treatments during the emission peak.The cumulative N_(2)O emissions from the CFM-treated soil were nearly 8-fold of those from the CF-treated soil.The CFM treatment stimulated N_(2)O production from bacterial nitrification and denitrification by increasing the abundance of genes linked to nitrifiers(ammonia-oxidizing bacterial(AOB)amoA and total comammox amoA)and denitrifiers(nirK,nirS,and qnorB),respectively.Importantly,DCD decreased cumulative N_(2)O emissions by an average of 73.3%,with better mitigation performance observed in the CFM-treated soil than in the CF-treated soil due to stronger inhibited nitrification and increased abundance of the nosZ gene,and altered bacterial community composition.The 16S rRNA sequencing further revealed that adding DCD to the CFM-treated soil resulted in declines in the abundances of bacterial phylum Actinobacteria and Chloroflexi that positively affected N_(2)O emissions;the opposite pattern prevailed for Gemmatimonadetes that negatively affected N_(2)O emissions.This study highlights the potential of manure application,when coupled with nitrification inhibitors,to achieve the dual goals of enhancing soil fertility and reducing environmental risk associated with N_(2)O emissions in tropical agricultural soils.展开更多
Water scarcity and soil salinization pose significant challenges to agriculture in the West Liaohe Plain,eastern Inner Mongolia,China.Shallow-buried drip irrigation can improve soil water use efficiency to alleviate w...Water scarcity and soil salinization pose significant challenges to agriculture in the West Liaohe Plain,eastern Inner Mongolia,China.Shallow-buried drip irrigation can improve soil water use efficiency to alleviate water shortage in agriculture and the application of lignite humic acid reduces the adverse effects of soil salinization.However,further research is needed to investigate the effects of different application rates of lignite humic acid and humic acid-based combined amendment on soil physicochemical properties,nutrient contents,and crop yield in saline-sodic farmlands under shallow-buried drip irrigation.A two-year field experiment was conducted with control without any amendment(CK),three treatments amended with 3 t/ha(H1),6 t/ha(H2),and 12 t/ha(H3)lignite humic acid,and three application rates with 15 t/ha(T1),22.5 t/ha(T2),and 30 t/ha(T3)lignite humic acid-based combined amendment in 2021 and2022.The results showed that H3 reduced soil bulk density,p H,electrical conductivity,and total alkalinity,while increasing the contents of soil organic matter,total nitrogen,and available potassium in the two-year experiment.Moreover,the maize yield in H3 increased by an average of 35.5%.T2 decreased soil bulk density,p H,total alkalinity,and increased maize yield by 16.2%,compared to the first year.These results suggest that T2 consistently improved both soil quality and crop yield.Correlation analyses showed that lignite humic acid and its complexes promote maize growth and increase yield by increasing soil organic matter and total nitrogen while reducing soil salinity and total alkalinity.Based on the comprehensive analysis of the field data and the results of the comprehensive evaluation of soil quality,it was determined that the appropriate improvement measures for saline-sodic farmlands under shallow-buried drip irrigation are the application of 12 t/ha of lignite humic acid and 22.5 t/ha of lignite humic acid-based combined amendment.This study demonstrates the effectiveness of lignite humic acid and its combined amendment in mitigating the constraints of saline-sodic farmlands and enhancing crop yields,providing a sustainable solution for improving saline-sodic farmlands in the West Liaohe Plain.展开更多
The effects of five amendments such as acetic acid（AA）, citric acid （CA）, ethylenediamine tetraacetic acid （EDTA）, sepiolite and phosphogypsum on growth and metal uptake of giant reed （Arundo donax L.） grown o...The effects of five amendments such as acetic acid（AA）, citric acid （CA）, ethylenediamine tetraacetic acid （EDTA）, sepiolite and phosphogypsum on growth and metal uptake of giant reed （Arundo donax L.） grown on soil contaminated by arsenic （As）, cadmium （Cd） and lead （Pb） were studied. The results showed that the shoot biomass of giant reed was enhanced by 24.8% and 15.0%, while superoxide mutase and catalase activities slightly varied when adding 5.0 mmol/kg CA and 2.5 mol/kg EDTA to soil as compared to the control, respectively. The concentrations of As, Cd and Pb in shoots were remarkably increased by the addition of 2.5 mmol/kg AA and CA, 5.0 mmol/kg EDTA, and 4.0 g/kg sepiolite as compared to the control. The accumulations of As and Cd were also significantly enhanced in the above condition, while the shoot Pb accumulation was noticeably enhanced by amending with 4.0 g/kg sepiolite and 8.0 g/kg phosphogysum, respectively. The results suggested that AA, CA and sepiolite could be used as optimum soil amendments for giant reed remediation system.展开更多
[Objective] The aim of this study was to evaluate the effects of soil amend- ment composed of biochar and inorganic mineral material on growth and develop- ment, yield and output value of flue-cured tobacco in South A...[Objective] The aim of this study was to evaluate the effects of soil amend- ment composed of biochar and inorganic mineral material on growth and develop- ment, yield and output value of flue-cured tobacco in South Anhui Province. [Method] A field plot experiment was conducted. The agronomic traits, yield and output value, as well as appearance quality and flavor of flue-cured tobacco were evaluated. [Re- suit] The soil amendments composed of biochars and inorganic mineral materials could significantly increase plant height, stem diameter, leaf size, yield and output of flue-cured tobacco, as well as proportion of first-grade tobacco leaves at the middle and late growth period. The yield in the X3 treatment group （70% T20 ＋ 30% ZC） was highest, and it was higher than that in the control group by 398 kg/hm2. Com- pared with that in the control group, the output of flue-cured tobacco in the X3 treatment group was increased by 10 290 yuan/hm2. In terms of appearance quality and flavor, the flue-cured tobacco leaves in the soil amendment treatment groups were all better than those in the control group. [Conclusion] The application of soil amendment composed of biochar and inorganic mineral material is an effective mea- sure to improve tobacco-growing soil, promote tobacco growth and development, im- prove tobacco yield and output and improve tobacco leaf quality in South Anhui re- gion.展开更多
Definitions and features of eco-park and theme park were introduced as well as their differences, it was proposed that by applying cultural themes suited to regional ecological resources in the construction of eco-par...Definitions and features of eco-park and theme park were introduced as well as their differences, it was proposed that by applying cultural themes suited to regional ecological resources in the construction of eco-park, the eco-park could achieve not only desired ecological benefits, but also social and economic benefits, and the optimal comprehensive benefits. Design of Baiyunzhai Demonstration Eco-park was taken for an example, integration of eco-park and farming culture was confirmed as the nature, principles of "adaptation to actual conditions, amended protection and construction of plant system" proposed, three functional areas of "Colorful Forest Belt, Yiyun Health Maintenance Zone, Lakefront Meditation Zone" are given on the basis of actual terrains, planning highlights and desired landscape effects expounded to promote the value of regional cultures in Chongqing by building Baiyunzhai Eco-park.展开更多
Heavy metals in variable charge soil are highly bioavailable and easy to transfer into plants. Since it is impossible to completely eliminate rice planting on contaminated soils, some remediation and mitigation techni...Heavy metals in variable charge soil are highly bioavailable and easy to transfer into plants. Since it is impossible to completely eliminate rice planting on contaminated soils, some remediation and mitigation techniques are necessary to reduce metal bioavailability and uptake by rice. This pot experiment investigated the effects of seven amendments on the growth of rice and uptake of heavy metals from a paddy soil that was contaminated by copper and cadmium. The best results were from the application of limestone that increased grain yield by 12.5-16.5 fold, and decreased Cu and Cd concentrations in grain by 23.0%--50.4%. Application of calcium magnesium phosphate, calcium silicate, pig manure, and peat also increased the grain yield by 0.3-15.3 fold, and effectively decreased the Cu and Cd concentrations in grain. Cd concentration in grain was slightly reduced in the treatments of Chinese milk vetch and zinc sulfate. Concentrations of Cu and Cd in grain and straw were dependent on the available Cu and Cd in the soils, and soil available Cu and Cd were significantly affected by the soil pH.展开更多
Excessive use of agro-chemicals （such as mineral fertilizers） poses potential risks to soil quality. Application of organic amendments and reduction of inorganic fertilizer are economically feasible and environmenta...Excessive use of agro-chemicals （such as mineral fertilizers） poses potential risks to soil quality. Application of organic amendments and reduction of inorganic fertilizer are economically feasible and environmentally sound approaches to de- velop sustainable agriculture. This study investigated and evaluated the effects of mineral fertilizer reduction and partial substitution of organic amendment on soil fertility and heavy metal content in a 10-season continually planted vegetable field during 2009-2012. The experiment included four treatments： 100% chemical fertilizer （CF100）, 80% chemical fertilizer （CF80）, 60% chemical fertilizer and 20% organic fertilizer （CF60＋OM20）, and 40% chemical fertilizer and 40% organic fertilizer （CF40＋OM40）. Soil nutrients, enzyme activity and heavy metal content were determined. The results showed that single chemical fertilizer reduction （CF80） had no significant effect on soil organic matter content, soil catalase activity and soil heavy metal content, but slightly reduced soil available N, P, K, and soil urease activity, and significantly reduced soil acid phosphatase activity. Compared with CF100, 40 or 60% reduction of chemical fertilizer supplemented with organic fertilizer （CF60＋OM20, CF40＋OM40） significantly increased soil organic matter, soil catalase activity and urease activity especially in last several seasons, but reduced soil available P, K, and soil acid phosphatase activity. In addition, continu- ous application of organic fertilizer resulted in higher accumulation of Zn, Cd, and Cr in soil in the late stage of experiment, which may induce adverse effects on soil health and food safety.展开更多
The aim of this study was to characterize the biological stability and maturity degree of compost during a controlled pile-composting trial of mixed vegetable residues （VR） collected from markets of Tunis City with ...The aim of this study was to characterize the biological stability and maturity degree of compost during a controlled pile-composting trial of mixed vegetable residues （VR） collected from markets of Tunis City with residues of Posidonia oceanica （PoR）, collected from Tunis beaches. The accumulation in beaches （as well as their removal） constitutes a serious environmental problem in all Mediterranean countries particularly in Tunisia. Aerobic-thermophilic composting is the most reasonable way to profit highly-valuable content of organic matter in these wastes for agricultural purposes. The physical, chemical, and biological parameters were monitored during composting over 150 d. The most appropriate parameters were selected to establish the maturity degree. The main result of this research was the deduction of the following maturity criterion： （a） C/N ratio 〈 15; （b） NH4^＋-N 〈 400 mg/kg; （c） CO2-C 〈 2000 mg CO2-C/kg; （d） dehydrogenase activity 〈 1 mg TPF/g dry matter; （e） germination index （GI） 〉 80%. These five parameters, considered jointly are indicative of a high maturity degree and thus of a high-quality organic amendment which employed in a rational way, may improve soil fertility and soil quality. The mature compost was relatively rich in N （13.0 g/kg）, P （4.74 g/kg） and MgO （15.80 g/kg）. Thus composting definitively constitutes the most optimal option to exploit these wastes.展开更多
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.
文摘State Administration for Market Regulation and National Standardization Administration of China have approved the following 758 voluntary national standards and 6 voluntary national standards with amendment.
基金financially supported by the National Science & Technology Fundamental Resources Investigation Project of China (2021FY100501)the Youth Innovation of Chinese Academy of Agricultural Sciences (Y2023QC16)。
文摘Long-term manure application has the potential to alleviate soil acidification, and increase carbon sequestration and nutrient availability, thus improving cropland fertility. However, the mechanisms behind greenhouse gas N_(2)O emissions from acidic soil mediated by long-term manure application remain poorly understood. Herein, we investigated N_(2)O emission and its linkage with gross N mineralization and nitrification rates, as well as nitrifying and denitrifying microbes in an acidic upland soil subjected to 36-year fertilization treatments, including an unfertilized control(CK), inorganic fertilizer(F), 2× rate of inorganic fertilizer(2F), manure(M), and the combination of inorganic fertilizer and manure(FM) treatments. Compared to the CK treatment(1.34 μg N kg^(-1) d^(-1)), fertilization strongly increased N_(2)O emissions by 34-fold on average, with more pronounced increases in the manure-amendment(10.6-169 μg N kg^(-1) d^(-1)) than those in the inorganic fertilizer treatments(3.26-5.51 μg N kg^(-1) d^(-1)). The manure amendment-stimulated N_(2)O emissions were highly associated with increased soil pH, mean weight diameter of soil aggregates, substrate availability(e.g., particulate organic carbon, NO_(3)^(-)and available phosphorus), gross N mineralization rates, denitrifier abundances and the(nirK+nirS)/nosZ ratio. These findings suggest that the increased N_(2)O emissions primarily resulted from alleviated acidification, increased substrate availability and improved soil structure, thus enhancing microbial N mineralization and favoring N_(2)O^(-)producing denitrifiers over N_(2)O consumers. Moreover, ammonia-oxidizing bacteria(AOB) rather than ammonia-oxidizing archaea(AOA) positively correlated with soil NO_(3)^(-)concentration and N_(2)O emissions, indicating that nitrification indirectly contributed to N_(2)O production by supplying NO_(3)^(-)for denitrification. Collectively, manure amendment potentially stimulates N_(2)O emissions, primarily resulting from alleviated soil acidification and increased substrate availability, thus enhancing N mineralization and denitrifier-mediated N_(2)O production. Our findings suggest that consideration should be given to the greenhouse gas budgets of agricultural ecosystems when applying manure for managing the pH and fertility of acidic soils.
文摘An amendment to the Electoral Law of the National People’s Congress and Local People’s Congresses of the People’s Republic of China providing equal legislative representation to rural and urban people was ratified at the closing meeting of the Third Session of the 1 1th
基金supported by the National Natural Science Foundation of China(42177341)the Natural Science Basic Research Program of Shanxi,China(202203021222138).
文摘Organic material combined with inorganic fertilizer has been shown to greatly improve crop yield and maintain soil fertility globally. However, it remains unclear if crop yield and soil fertility can be sustained in the long term under the combined application of organic and inorganic fertilizers. Three long-term field trials were conducted to investigate the effects of organic amendments on the grain sustainable yield index(SYI), soil fertility index(SFI)and nutrient balance in maize–wheat cropping systems of central and southern China during 1991–2019. Five treatments were included in the trials: 1) no fertilization(control);2) balanced mineral fertilization(NPK);3) NPK plus manure(NPKM);4) high dose of NPK plus manure(1.5NPKM);and 5) NPK plus crop straw(NPKS). Over time, the grain yields of wheat and maize showed an increasing trend in all four fertilization treatments at the Yangling(YL) and Zhengzhou(ZZ) locations, while they declined at Qiyang(QY). The grain yield in the NPKM and 1.5NPKM treatments gradually exceeded that of the NPK and NPKS treatments at the QY site. The largest SYI was recorded in the NPKM treatment across the three sites, suggesting that inorganic fertilizer combined with manure can effectively improve crop yield sustainability. Higher SYI values were recorded at the YL and ZZ sites than at the QY site, possibly because the soil was more acid at QY. The key factors affecting grain yield were soil available phosphorus(AP) and available potassium(AK) at the YL and ZZ sites, and pH and AP at the QY site.All fertilization treatments resulted in soil N and P surpluses at the three sites, but soil K surpluses were recorded only at the QY site. The SFI was greater in the 1.5NPKM, NPKM and NPKS treatments than in the NPK treatment by 13.3–40.0 and 16.4–63.6% at the YL and ZZ sites, respectively, and was significantly higher in the NPKM and 1.5NPKM treatments than in the NPK and NPKS treatments at the QY site. A significant, positive linear relationship was found between SFI and crop yield, and SYI and nutrient balance, indicating that grain yield and its sustainability significantly increased with increasing soil fertility. The apparent N, P and K balances positively affected SFI.This study suggests that the appropriate amount of manure mixed with mineral NPK fertilizer is beneficial to the development of sustainable agriculture, which effectively increases the crop yield and yield sustainability by improving soil fertility.
基金supported by the National Natural Science Foundation of Shandong(No.ZR2020ZD20)the National Natural Science Foundation of China(No.22193051)+1 种基金the National Young Top-Notch Talents(No.W03070030)the Youth Innovation Promotion Association of the Chinese Academy of Sciences(No.Y202011).
文摘Identification of the most appropriate chemically extractable pool for evaluating Cd and Pb availability remains elusive,hindering accurate assessment on environmental risks and effectiveness of remediation strategies.This study evaluated the feasibility of European Community Bureau of Reference(BCR)sequential extraction,Ca(NO_(3))_(2)extraction,and water extraction on assessing Cd and Pb availability in agricultural soil amended with slaked lime,magnesium hydroxide,corn stover biochar,and calcium dihydrogen phosphate.Moreover,the enriched isotope tracing technique(^(112)Cd and^(206)Pb)was employed to evaluate the aging process of newly introduced Cd and Pbwithin 56 days’incubation.Results demonstrated that extractable pools by BCR and Ca(NO_(3))_(2)extraction were little impacted by amendments and showed little correlation with soil pH.This is notable because soil pH is closely linked to metal availability,indicating these extraction methods may not adequately reflect metal availability.Conversely,water-soluble concentrations of Cd and Pb were markedly influenced by amendments and exhibited strong correlations with pH(Pearson’s r:-0.908 to-0.825,P<0.001),suggesting water extraction as a more sensitive approach.Furthermore,newly introduced metals underwent a more evident aging process as demonstrated by acid-soluble and water-soluble pools.Additionally,water-soluble concentrations of essential metals were impacted by soil amendments,raising caution on their potential effects on plant growth.These findings suggest water extraction as a promising and attractive method to evaluate Cd and Pb availability,which will help provide assessment guidance for environmental risks caused by heavy metals and develop efficient remediation strategies.
基金jointly funded by the Sichuan Provincial Natural Science Foundation of China(Grant No.2023NSFSC0378)the Jiuzhaigou Lake Swamp and River Ecological Restoration Research Project(N5132112022000246)the Research base and Support provided by Jiuzhaigou Administration for this study。
文摘Rubble deposits with a high concentration of rock debris were created after the powerful earthquakes in Jiuzhaigou.Because of the restricted soil resources,water leaks,and nutrient deficits,these deposits pose serious obstacles for vegetation regeneration.The purpose of this study was to investigate the main mechanisms controlling soil water retention and evaluate the effects of different amendments on the hydraulic characteristics and water-holding capacity of collapsed rubble soils.Finegrained soil,forest humus,crushed straw,and organic components that retain water were added to the altered soils to study the pore structure images and soil-water characteristic curves.Comparing understory humus to other supplements,the results showed a considerable increase in the soil's saturated and wilting water content.The saturated water content and wilting water content rose by 17.9%and 4.3%,respectively,when the percentage of understory soil reached 30%.Additionally,the enhanced soil's microporosity and total pore volume increased by 45.33%and 11.27%,respectively,according to nuclear magnetic imaging.It was shown that while clay particles and organic matter improved the soil's ability to adsorb water,they also increased the soil's total capacity to store water.Fine particulate matter did this by decreasing macropores and increasing capillary pores.These results offer an essential starting point for creating strategies for soil repair that would encourage the restoration of plants on slopes that have been damaged.
基金the financial support from the National Natural Science Foundation of China(Nos.22378154 and 21975089)the Fundamental Research Funds for the Central Universities of China(No.2017KFKJFP002)。
文摘Despite the promising outcomes observed in individual applications of biochar and polyvinyl alcohol(PVA)in soil,the impact of their combined usage remains inadequately understood.This study systematically explores the effects of concurrent biochar and PVA application on key soil parameters,including pH,water-holding capacity(WHC),and dynamic moisture content(MC),and the photosynthetic resilience and growth of the cyanobacterium Microcoleus vaginatus in a desert soil.Biochars,generated at different pyrolysis temperatures(300-600℃),were applied to the soil at varying rates(1%-6%),while PVA was introduced at a mass percentage of 0.05%.The photosynthetic resilience and biomass accumulation of M.vaginatus in different treatments were examined every 7 d during the 28-d exposure to dry conditions after 60-d water supply.The combined application of biochar and PVA resulted in a reduction of soil pH,coupled with significant improvements in WHC and dynamic MC.Moreover,this combined approach exhibited superior effects on the photosynthetic resilience and crust thickness(0.9-3.5 mm)of M.vaginatus compared to the application of biochar and PVA in isolation.Incremental increase in biochar application rate from 0% to 6% demonstrated a notable enhancement in the chlorophyll a content of M.vaginatus.Cyanobacterial crust thickness and exopolysaccharide content exhibited positive correlations with biochar application rate.Thus,combined application of biochar and PVA is cost-effective for enhancing soil properties and cyanobacterial biomass,which is of significance for combating desertification.
文摘Biochar has emerged as a promising tool for enhancing vineyard sustainability by improving soil properties and mitigating climate change impacts.This review highlights key findings on biochar’s role in viticulture,focusing on its effects on soil fertility,water retention,and plant physiology.Field and pot studies demonstrate that biochar amendments enhance soil structure,increase cation exchange capacity(CEC),and promote water availability,leading to improved drought resistance in grapevines.However,the impacts on grape yield,physiology,and quality remain inconclusive,with some studies reporting benefits while others show neutral effects.Future research should focus on optimizing biochar application rates,understanding its interactions with soil microbiota,and assessing long-term impacts on grape production and wine quality.Additionally,addressing potential risks,such as heavy metal contamination and changes in microbial communities,is crucial for its safe and effective use.This review aims to supply a comprehensive assessment of our knowledge about the incidence and consequences of biochar on soil,including its potential use in soil remediation and concerns regarding its possible negative impacts,with a focus on its effects on vine physiology and grape production.
基金supported by the National Natural Science Foundation of China(No.42007128)the Fundamental Research Funds for the Central Universities(No.2024QNYL30)the Graduate Research and Practice Projects of Minzu University of China(No.SZKY2024034).
文摘Traditional studies of microbial succession under iron-carbon composite(Fe-C)amendment application have focused on the entire microbial community,with limited attention to the responses and ecological roles of abundant or rare taxa.Herein,a 90-day microcosm incubation was conducted to investigate the effects of three Fe-C amendments,including Fe_(3)O_(4)-modified biochar(FeC-B),ferrihydrite-natural humic acid(FeC-N),and ferrihydrite-synthetic humic-like acid(FeC-S),on distribution patterns,assembly processes,and ecological functions of both abundant and rare subcommunities.Our results showed that Fe-C amendments significantly affected theα-diversity of rare taxa,particularly under FeC-B treatment,with minimal impact on abundant taxa.Fe-C amendments also reshaped the community structures of both groups.Rare taxa,representing 63.9%of Operational Taxonomic Unit(OTU)richness but only 1.6%of total abundance,played a key role in community diversity and were more susceptible to Fe-C amendments.Certain rare taxa transitioned to abundant status,demonstrating their potential as a microbial seed bank.Abundant taxa were positioned more centrally within the networks,and Fe-C applications promoted cooperative interactions between abundant and rare species.Deterministic processes dominated the assembly of the rare subcommunity,while stochastic processes primarily influenced the abundant bacterial community.Fe-C amendments reduced community differentiation among rare taxa while increasing variability among abundant groups.Functional diversity of rare groups surpassed that of abundant groups,with notable enhancement in nitrogen cycling-related genes under Fe-C treatments.This study highlights the complementary roles of abundant and rare taxa in soil remediation,providing insights for optimizing remediation strategies.
基金supported by the National Natural Science Foundation of China(Nos.42007098 and 32001209)the Major Science and Technology Plan of Hainan Province,China(No.ZDKJ2021008)+1 种基金the Natural Science Foundation of Hainan Province,China(Nos.320RC687 and 421QN0915)the Central PublicInterest Scientific Institution Basal Research Fund for Chinese Academy of Tropical Agricultural Sciences(Nos.1630042025001,1630042025011,and 1630042025012)。
文摘Organic amendments(OM)can profoundly affect soil nitrous oxide(N_(2)O)emissions via changing nitrogen(N)cycles.However,mechanistic insights into how nitrification inhibitors modulate the responses of soil N_(2)O emissions to successive applications of OM are currently insufficient.In this study,we performed a laboratory experiment to examine N_(2)O emissions from a tropical vegetable soil subjected to six years of chemical fertilization(CF)and chemical fertilization combined with manure application(CFM)and evaluate the mitigation effectiveness of nitrification inhibitor dicyandiamide(DCD)under each management regime.Isotopocule mapping showed that bacterial nitrification and/or fungal denitrification accounted for 77.4%–88.5%of total N_(2)O production across treatments during the emission peak.The cumulative N_(2)O emissions from the CFM-treated soil were nearly 8-fold of those from the CF-treated soil.The CFM treatment stimulated N_(2)O production from bacterial nitrification and denitrification by increasing the abundance of genes linked to nitrifiers(ammonia-oxidizing bacterial(AOB)amoA and total comammox amoA)and denitrifiers(nirK,nirS,and qnorB),respectively.Importantly,DCD decreased cumulative N_(2)O emissions by an average of 73.3%,with better mitigation performance observed in the CFM-treated soil than in the CF-treated soil due to stronger inhibited nitrification and increased abundance of the nosZ gene,and altered bacterial community composition.The 16S rRNA sequencing further revealed that adding DCD to the CFM-treated soil resulted in declines in the abundances of bacterial phylum Actinobacteria and Chloroflexi that positively affected N_(2)O emissions;the opposite pattern prevailed for Gemmatimonadetes that negatively affected N_(2)O emissions.This study highlights the potential of manure application,when coupled with nitrification inhibitors,to achieve the dual goals of enhancing soil fertility and reducing environmental risk associated with N_(2)O emissions in tropical agricultural soils.
基金Under the auspices of the National Key Research and Development Program of China(No.2022YFD1500501)the Innovation Team Project of Northeast Institute of Geography and Agroecology,Chinese Academy of Sciences(No.2023CXTD02)+2 种基金the National Natural Science Foundation of China(No.41971066)the Key Laboratory Foundation of Mollisols Agroecology(No.2020ZKHT-03)the High Tech Fund Project of S&T Cooperation between Jilin Province and Chinese Academy of Sciences(No.2022SYHZ0018)。
文摘Water scarcity and soil salinization pose significant challenges to agriculture in the West Liaohe Plain,eastern Inner Mongolia,China.Shallow-buried drip irrigation can improve soil water use efficiency to alleviate water shortage in agriculture and the application of lignite humic acid reduces the adverse effects of soil salinization.However,further research is needed to investigate the effects of different application rates of lignite humic acid and humic acid-based combined amendment on soil physicochemical properties,nutrient contents,and crop yield in saline-sodic farmlands under shallow-buried drip irrigation.A two-year field experiment was conducted with control without any amendment(CK),three treatments amended with 3 t/ha(H1),6 t/ha(H2),and 12 t/ha(H3)lignite humic acid,and three application rates with 15 t/ha(T1),22.5 t/ha(T2),and 30 t/ha(T3)lignite humic acid-based combined amendment in 2021 and2022.The results showed that H3 reduced soil bulk density,p H,electrical conductivity,and total alkalinity,while increasing the contents of soil organic matter,total nitrogen,and available potassium in the two-year experiment.Moreover,the maize yield in H3 increased by an average of 35.5%.T2 decreased soil bulk density,p H,total alkalinity,and increased maize yield by 16.2%,compared to the first year.These results suggest that T2 consistently improved both soil quality and crop yield.Correlation analyses showed that lignite humic acid and its complexes promote maize growth and increase yield by increasing soil organic matter and total nitrogen while reducing soil salinity and total alkalinity.Based on the comprehensive analysis of the field data and the results of the comprehensive evaluation of soil quality,it was determined that the appropriate improvement measures for saline-sodic farmlands under shallow-buried drip irrigation are the application of 12 t/ha of lignite humic acid and 22.5 t/ha of lignite humic acid-based combined amendment.This study demonstrates the effectiveness of lignite humic acid and its combined amendment in mitigating the constraints of saline-sodic farmlands and enhancing crop yields,providing a sustainable solution for improving saline-sodic farmlands in the West Liaohe Plain.
基金Project (2012BAC09B04) supported by National Key Technology Research and Development Program of the Ministry of Science and Technology of ChinaProject (2010-277-027) supported by Science and Technology Foundation of Environmental Protection in Hunan Province,ChinaProject (2011SK3262) supported by Science and Technology Planning of Hunan Province,China
文摘The effects of five amendments such as acetic acid（AA）, citric acid （CA）, ethylenediamine tetraacetic acid （EDTA）, sepiolite and phosphogypsum on growth and metal uptake of giant reed （Arundo donax L.） grown on soil contaminated by arsenic （As）, cadmium （Cd） and lead （Pb） were studied. The results showed that the shoot biomass of giant reed was enhanced by 24.8% and 15.0%, while superoxide mutase and catalase activities slightly varied when adding 5.0 mmol/kg CA and 2.5 mol/kg EDTA to soil as compared to the control, respectively. The concentrations of As, Cd and Pb in shoots were remarkably increased by the addition of 2.5 mmol/kg AA and CA, 5.0 mmol/kg EDTA, and 4.0 g/kg sepiolite as compared to the control. The accumulations of As and Cd were also significantly enhanced in the above condition, while the shoot Pb accumulation was noticeably enhanced by amending with 4.0 g/kg sepiolite and 8.0 g/kg phosphogysum, respectively. The results suggested that AA, CA and sepiolite could be used as optimum soil amendments for giant reed remediation system.
基金Supported by Special Project for Shanghai and Anhui Modern Tobacco Agricultural High-tech Demonstration Park(CF56.1-ZJ1)~~
文摘[Objective] The aim of this study was to evaluate the effects of soil amend- ment composed of biochar and inorganic mineral material on growth and develop- ment, yield and output value of flue-cured tobacco in South Anhui Province. [Method] A field plot experiment was conducted. The agronomic traits, yield and output value, as well as appearance quality and flavor of flue-cured tobacco were evaluated. [Re- suit] The soil amendments composed of biochars and inorganic mineral materials could significantly increase plant height, stem diameter, leaf size, yield and output of flue-cured tobacco, as well as proportion of first-grade tobacco leaves at the middle and late growth period. The yield in the X3 treatment group （70% T20 ＋ 30% ZC） was highest, and it was higher than that in the control group by 398 kg/hm2. Com- pared with that in the control group, the output of flue-cured tobacco in the X3 treatment group was increased by 10 290 yuan/hm2. In terms of appearance quality and flavor, the flue-cured tobacco leaves in the soil amendment treatment groups were all better than those in the control group. [Conclusion] The application of soil amendment composed of biochar and inorganic mineral material is an effective mea- sure to improve tobacco-growing soil, promote tobacco growth and development, im- prove tobacco yield and output and improve tobacco leaf quality in South Anhui re- gion.
文摘Definitions and features of eco-park and theme park were introduced as well as their differences, it was proposed that by applying cultural themes suited to regional ecological resources in the construction of eco-park, the eco-park could achieve not only desired ecological benefits, but also social and economic benefits, and the optimal comprehensive benefits. Design of Baiyunzhai Demonstration Eco-park was taken for an example, integration of eco-park and farming culture was confirmed as the nature, principles of "adaptation to actual conditions, amended protection and construction of plant system" proposed, three functional areas of "Colorful Forest Belt, Yiyun Health Maintenance Zone, Lakefront Meditation Zone" are given on the basis of actual terrains, planning highlights and desired landscape effects expounded to promote the value of regional cultures in Chongqing by building Baiyunzhai Eco-park.
文摘Heavy metals in variable charge soil are highly bioavailable and easy to transfer into plants. Since it is impossible to completely eliminate rice planting on contaminated soils, some remediation and mitigation techniques are necessary to reduce metal bioavailability and uptake by rice. This pot experiment investigated the effects of seven amendments on the growth of rice and uptake of heavy metals from a paddy soil that was contaminated by copper and cadmium. The best results were from the application of limestone that increased grain yield by 12.5-16.5 fold, and decreased Cu and Cd concentrations in grain by 23.0%--50.4%. Application of calcium magnesium phosphate, calcium silicate, pig manure, and peat also increased the grain yield by 0.3-15.3 fold, and effectively decreased the Cu and Cd concentrations in grain. Cd concentration in grain was slightly reduced in the treatments of Chinese milk vetch and zinc sulfate. Concentrations of Cu and Cd in grain and straw were dependent on the available Cu and Cd in the soils, and soil available Cu and Cd were significantly affected by the soil pH.
基金financially supported by grants of the Key Projects in the Key Technologies R&D Program of China during the 12th Five-Year Plan period(2012BAD14B00)the Guangdong Provincial Science and Technology Plan Key Project,China(2012A020100003,2015A050502043)
文摘Excessive use of agro-chemicals （such as mineral fertilizers） poses potential risks to soil quality. Application of organic amendments and reduction of inorganic fertilizer are economically feasible and environmentally sound approaches to de- velop sustainable agriculture. This study investigated and evaluated the effects of mineral fertilizer reduction and partial substitution of organic amendment on soil fertility and heavy metal content in a 10-season continually planted vegetable field during 2009-2012. The experiment included four treatments： 100% chemical fertilizer （CF100）, 80% chemical fertilizer （CF80）, 60% chemical fertilizer and 20% organic fertilizer （CF60＋OM20）, and 40% chemical fertilizer and 40% organic fertilizer （CF40＋OM40）. Soil nutrients, enzyme activity and heavy metal content were determined. The results showed that single chemical fertilizer reduction （CF80） had no significant effect on soil organic matter content, soil catalase activity and soil heavy metal content, but slightly reduced soil available N, P, K, and soil urease activity, and significantly reduced soil acid phosphatase activity. Compared with CF100, 40 or 60% reduction of chemical fertilizer supplemented with organic fertilizer （CF60＋OM20, CF40＋OM40） significantly increased soil organic matter, soil catalase activity and urease activity especially in last several seasons, but reduced soil available P, K, and soil acid phosphatase activity. In addition, continu- ous application of organic fertilizer resulted in higher accumulation of Zn, Cd, and Cr in soil in the late stage of experiment, which may induce adverse effects on soil health and food safety.
基金The study is part of the 1999–2002 research program "Municipal solid waste treatment and compost agriculture application" which is supported jointly by the Tunisian Secretariat of Scientific Research and Technology
文摘The aim of this study was to characterize the biological stability and maturity degree of compost during a controlled pile-composting trial of mixed vegetable residues （VR） collected from markets of Tunis City with residues of Posidonia oceanica （PoR）, collected from Tunis beaches. The accumulation in beaches （as well as their removal） constitutes a serious environmental problem in all Mediterranean countries particularly in Tunisia. Aerobic-thermophilic composting is the most reasonable way to profit highly-valuable content of organic matter in these wastes for agricultural purposes. The physical, chemical, and biological parameters were monitored during composting over 150 d. The most appropriate parameters were selected to establish the maturity degree. The main result of this research was the deduction of the following maturity criterion： （a） C/N ratio 〈 15; （b） NH4^＋-N 〈 400 mg/kg; （c） CO2-C 〈 2000 mg CO2-C/kg; （d） dehydrogenase activity 〈 1 mg TPF/g dry matter; （e） germination index （GI） 〉 80%. These five parameters, considered jointly are indicative of a high maturity degree and thus of a high-quality organic amendment which employed in a rational way, may improve soil fertility and soil quality. The mature compost was relatively rich in N （13.0 g/kg）, P （4.74 g/kg） and MgO （15.80 g/kg）. Thus composting definitively constitutes the most optimal option to exploit these wastes.
