On the basis of making clear diversity characteristics of soil functions and multiple characteristics of income, this paper points out that the monetization of soil functions based functional maintenance and change de...On the basis of making clear diversity characteristics of soil functions and multiple characteristics of income, this paper points out that the monetization of soil functions based functional maintenance and change decision process can be regarded as a game process of different utilization methods at the background of different functions. The balance of this game process will determine monetary value of soil functions. After understanding money and monetization concepts, it introduces that measurability and exchangeability of soil functions provide objective conditions for monetization of soil functions. Finally, it discusses that usefulness value of soil functions provide basis for monetization of soil functions.展开更多
Soil microbial alpha diversity is essential for driving ecosystem functions and processes.However,little is known about the beta-diversity affect community functions.Here,we combine distinct community inocula using th...Soil microbial alpha diversity is essential for driving ecosystem functions and processes.However,little is known about the beta-diversity affect community functions.Here,we combine distinct community inocula using the dilution-to-extinction approach with two wheat genotypes to study the effect of microbial diversity loss on rhizosphere community assembly processes,which are related to beta-diversity(between-habitat diversity),and the consequences for ecosystem functions within greenhouse experiment.Compared with alpha-diversity,the bacterial and fungal community beta-diversity are stronger predictors of ecosystem functions(organic matter degradation,phosphorus supply capacity and nitrogen supply capacity),plant genotypes regulated the relationship between microbial diversity and ecosystem functions,with ecosystem functions being significant link to microbial diversity under different wheat genotypes.Loss of microbial diversity decreased the abundance of Bacterial_ASV6(Burkholderia)and increased Fungal_11(Altemaria)within the restored rhizosphere soil.Null modeling analysis showed that the deterministic assembly processes are dominant in bacterial community and fungal high-diversity(alpha-diversity)community,associating with the change of specialized functions(organic matter degradation,phosphorus supply capacity and nitrogen supply capacity)that are correlated with microbial diversity and specific microbial taxa.In addition,these two species were key role for regulating to the network cohesion.Overall,our study pointed out that the regulation of community assembly by microbial diversity loss limits the development of soil ecological functions and weakens the stability of rhizosphere microbial network,highlighting the potential regulatory effect of microbial taxa distribution on microbial community stability and changes of specific ecological functions.展开更多
Partial substitution of synthetic nitrogen(N)with organic fertilizers(PSOF)is of great significance in improving soil ecosystem functions in systems that have deteriorated due to the excessive application of chemical ...Partial substitution of synthetic nitrogen(N)with organic fertilizers(PSOF)is of great significance in improving soil ecosystem functions in systems that have deteriorated due to the excessive application of chemical N fertilizer.However,existing studies typically focus on individual soil functions,neglecting the fact that multiple functions occur simultaneously.It remains unclear how PSOF influences multiple soil functions and whether these impacts are related to soil microbial communities.Here,we examined the impacts of partial substitutions(25%–50%)of chemical N fertilizer with organic form(pig manure or municipal sludge)in a vegetable field on soil multifunctionality,by measuring a range of soil functions involving primary production(vegetable yield and quality),nutrient cycling(soil enzyme activities,ammonia volatilization,N leaching,and N runoff),and climate regulation(soil organic carbon sequestration and nitrous oxide emission).We observed that PSOF improved soil multifunctionality,with a 50%substitution of chemical N fertilizer with pig manure being the best management practice;the result was strongly related to the diversities and network complexities of bacteria and fungi.Random forest analysis further revealed that soil multifunctionality was best explained by the bacterial-fungal network complexity,followed by available phosphorus level and bacterial diversity.The PSOF also shifted the composition of bacterial and fungal communities,with increased relative abundances of dominant bacteria phyla,such as Bacteroidetes,Gemmatimonadetes,and Myxococcota,and fungal phyla,such as Basidiomycota and Olpidiomycota.The observed increases in soil multifunctionality were consistent with significant increases in the relative abundances of keystone taxa such as Blastocladiomycota,Chaetomiaceae,and Nocardiopsaceae.Together,these findings indicate that PSOF can enhance interactions within and among microbial communities and that such practices have the potential to improve soil ecosystem multifunctionality and contribute to the development of sustainable agriculture.展开更多
Trees provide multiple ecosystem services such as carbon sequestration,hydrological regulation and habitat for arboreal animals.However,they are often removed to support agricultural enterprises.Despite the importance...Trees provide multiple ecosystem services such as carbon sequestration,hydrological regulation and habitat for arboreal animals.However,they are often removed to support agricultural enterprises.Despite the importance of tree remnants,we know relatively little about how soils differ across sites of varying condition.Here,we describe a study where we examined the relative effects of trees,compared with unvegetated interspaces,on soil functions in remnant patches at sites in good and poor condition in two eucalypt communities in an irrigation area in eastern Australia.We found that,in general,carbon and nutrient cycling were relatively greater beneath trees,and in surface soils,but there were no clear trends in relation to site condition.The values of most soil attributes(e.g.,soluble and exchangeable cations,nitrogen,phosphorus)were greater beneath trees,indicating strong fertile island effects in both communities.Overall,our study confirms the importance of trees in remnant patches in agricultural landscapes,particularly those in sites of poor condition.It also suggests that soil processes may still be relatively intact,even in sites in poor condition.Our study reinforces the need to protect trees in remnant woodland reserves to maintain critical ecosystem functions related to nutrient retention.These remnants are important for achieving sustainable management of agricultural systems.展开更多
Soil multifunctionality represents a range of soil processes driven by the interactions between soil abiotic and biotic components.As a group of ubiquitous fungi that form mutualistic symbiotic associations with a vas...Soil multifunctionality represents a range of soil processes driven by the interactions between soil abiotic and biotic components.As a group of ubiquitous fungi that form mutualistic symbiotic associations with a vast array of terrestrial plants,arbuscular mycorrhizal(AM)fungi may play a critical role in maintaining soil multifunctionality,but the characteristics of their contributions remain to be unraveled.This mini review aims to disentangle the contributions of AM fungi to soil multifunctionality.We provide a framework of concepts about AM fungi making crucial contributions to maintaining multiple soil functions,including primary productivity,nutrient cycling,water regulation and purification,carbon and climate regulation,habitat for biodiversity,disease and pest control,and pollutant degradation and detoxification,via a variety of pathways,particularly contributing to soil and plant health.This review contends that AM fungi,as a keystone component of soil microbiome,can govern soil multifunctionality,ultimately promoting ecosystem services.展开更多
Managing fertilization in integrated crop-livestock systems(ICLS)during periods of low nutrient export,known as system fertilization,can optimize nutrient use by enhancing the soil's biochemical and physical-hydri...Managing fertilization in integrated crop-livestock systems(ICLS)during periods of low nutrient export,known as system fertilization,can optimize nutrient use by enhancing the soil's biochemical and physical-hydric properties.However,interdisciplinary studies on processes that improve input utilization in ICLS remain scarce.This study aimed to assess the relationships between the effciencies of different nutrient management strategies in ICLS and pure crop systems(PCS)and the biochemical and physical-hydric quality of soil.Two fertilization strategies(system fertilization and crop fertilization)and two cropping systems(ICLS and PCS)were evaluated in a randomized block design with three replicates.In the PCS,soybean was grown followed by ryegrass as a cover crop.In the ICLS,sheep grazed on the ryegrass.In the crop fertilization,phosphorus and potassium were applied to the soybean planting,and nitrogen was applied in the ryegrass establishment.Nitrogen,phosphorus,and potassium were applied during ryegrass establishment in the system fertilization.Soil quality indexes were calculated using fourteen physical-hydric and biochemical soil indicators,and primary production and nutrient utilization effciency were evaluated.System fertilization in ICLS enhanced the soil functions of water storage and availability for plants,structural stability,and resistance to degradation.System fertilization in ICLS improved the soil quality by 14%over PCS and 13%over crop fertilization in ICLS.Notably,this optimized system yielded the highest primary production.These findings underscore the pivotal role of system fertilization in ICLS to boost food production and enhance soil ecosystem services without increasing the consumption of external fertilizers.They advocate for a strategic shift towards system-level fertilization in integrated systems,and demonstrate for the frst time in ICLS,the delicate balance between nutrient management,soil health,and sustainable productivity.展开更多
Changes in soil biological and biochemical properties under different land uses in the subtropical region of China were investigated in order to develop rational cultivation and fertilization management. A small water...Changes in soil biological and biochemical properties under different land uses in the subtropical region of China were investigated in order to develop rational cultivation and fertilization management. A small watershed of subtropical region of China was selected for this study. Land uses covered paddy fields, vegetable farming, fruit trees, upland crops, bamboo stands, and forestry. Soil biological and biochemical properties included soil organic C and nutrient contents, mineralization of soil organic C, and soil microbial biomass and community functional diversity. Soil organic C and total N contents, microbial biomass C and N, and respiration intensity under different land uses were changed in the following order： paddy fields （and vegetable farming） 〉 bamboo stands 〉 fruit trccs （and upland）. The top surface （0-15 cm） paddy fields （and vegetable farming） were 76.4 and 80.8% higher in soil organic C and total N contents than fruit trees （and upland） soils, respectively. Subsurface paddy soils （15-30 cm） were 59.8 and 67.3% higher in organic C and total N than upland soils, respectively. Soil microbial C, N and respiration intensity in paddy soils （0-15 cm） were 6.36, 3.63 and 3.20 times those in fruit tree （and upland） soils respectively. Soil microbial metabolic quotient was in the order： fruit trees （and upland） 〉 forestry 〉 paddy fields. Metabolic quotient in paddy soils was only 47.7% of that in fruit tree （and upland） soils. Rates of soil organic C mineralization during incubation changed in the order： paddy fields 〉 bamboo stands 〉 fruit trees （and upland） and soil bacteria population： paddy fields 〉 fruit trees （and upland） 〉 forestry. No significant difference was found for fungi and actinomycetes populations. BIOLOG analysis indicated a changing order of paddy fields 〉 fruit trees （and upland） 〉 forestry in values of the average well cell development （AWCD） and functional diversity indexes of microbial community. Results also showed that the conversion from paddy fields to vegetable farming for 5 years resulted in a dramatic increase in soil available phosphorus content while insignificant changes in soil organic C and total N content due to a large inputs of phosphate fertilizers. This conversion caused 53, 41.5, and 41.3% decreases in soil microbial biomass C, N, and respiration intensity, respectively, while 23.6% increase in metabolic quotient and a decrease in soil organic C mineralization rate. Moreover, soil bacteria and actinomycetes populations were increased slightly, while fungi population increased dramatically. Functional diversity indexes of soil microbial community decreased significantly. It was concluded that land uses in the subtropical region of China strongly affected soil biological and biochemical properties. Soil organic C and nutrient contents, mineralization of organic C and functional diversity of microbial community in paddy fields were higher than those in upland and forestry. Overuse of chemical fertilizers in paddy fields with high fertility might degrade soil biological properties and biochemical function, resulting in deterioration of soil biological quality.展开更多
With the widespread cultivation of transgenic crops, there is increasing concern about unintended effects of these crops on soil environmental quality. In this study, we used the Biolog method and ELISA to evaluate th...With the widespread cultivation of transgenic crops, there is increasing concern about unintended effects of these crops on soil environmental quality. In this study, we used the Biolog method and ELISA to evaluate the possible effects of Osr HSA transgenic rice on soil microbial utilization of carbon substrates under field conditions. There were no significant differences in average well-color development(AWCD) values, Shannon–Wiener diversity index(H), Simpson dominance indices(D) and Shannon–Wiener evenness indices(E) of microbial communities in rhizosphere soils at eight samplings between Osr HSA transgenic rice and its non-transgenic counterpart. The main carbon sources utilized by soil microbes were carbohydrates, carboxylic acids, amino acids and polymers. The types,capacities and patterns of carbon source utilization by microbial communities in rhizosphere soils were similar throughout the detection period. We detected no Osr HSA protein in the roots of Osr HSA transgenic rice. We concluded that Osr HSA transgenic rice and the r HSA protein it produced did not alter the functional diversity of microbial communities in the rhizosphere.展开更多
Ecological effects of crude oil residues on weed rhizospheres are still vague. The quantitative and diversity changes and metabolic responses of soil-bacterial communities in common dandelion （Taraxacum officinale）,...Ecological effects of crude oil residues on weed rhizospheres are still vague. The quantitative and diversity changes and metabolic responses of soil-bacterial communities in common dandelion （Taraxacum officinale）, jerusalem artichoke （Silphiurn perfoliatum L.） and evening primrose （A colypha australis L.） rhizospheric soils were thus examined using the method of carbon source utilization. The results indicated that there were various toxic effects of crude oil residues on the growth and reproduction of soil bacteria, but the weed rhizospheres could mitigate the toxic effects. Total heterotrophic counting colony-forming units （CFUs） in the rhizospheric soils were significantly higher than those in the non-rhizospheric soils. The culturable soil-bacterial CFUs in the jerusalem artichoke （S. perfoliatum） rhizosphere polluted with 0.50 kg/pot of crude oil residues were almost twice as much as those with 0.25 kg/pot and without the addition of crude oil residues. The addition of crude oil residues increased the difference in substrate evenness, substrate richness, and substrate diversity between non-rhizospheric and rhizospheric soils of T. officinale and A. australis, but there was no significant （p〉0.05） difference in the Shannon＇s diversity index between non-rhizospheric and rhizospheric soils of S. perfoliatum. The rhizospheric response of weed species to crude oil residues suggested that S. perfoliatum may be a potential weed species for the effective plant-microorganism bioremediation of contaminated soils by crude oil residues.展开更多
Exploration of soil environmental characteristics governing soil microbial community structure and activity may improve our understanding of biogeochemical processes and soil quality. The impact of soil environmental ...Exploration of soil environmental characteristics governing soil microbial community structure and activity may improve our understanding of biogeochemical processes and soil quality. The impact of soil environmental characteristics especially organic carbon availability after 15-yr different organic and inorganic fertilizer inputs on soil bacterial community structure and functional metabolic diversity of soil microbial communities were evaluated in a 15-yr fertilizer experiment in Changping County, Beijing, China. The experiment was a wheat-maize rotation system which was established in 1991 including four different fertilizer treatments. These treatments included： a non-amended control（CK）, a commonly used application rate of inorganic fertilizer treatment（NPK）; a commonly used application rate of inorganic fertilizer with swine manure incorporated treatment（NPKM）, and a commonly used application rate of inorganic fertilizer with maize straw incorporated treatment（NPKS）. Denaturing gradient gel electrophoresis（DGGE） of the 16 S r RNA gene was used to determine the bacterial community structure and single carbon source utilization profiles were determined to characterize the microbial community functional metabolic diversity of different fertilizer treatments using Biolog Eco plates. The results indicated that long-term fertilized treatments significantly increased soil bacterial community structure compared to CK. The use of inorganic fertilizer with organic amendments incorporated for long term（NPKM, NPKS） significantly promoted soil bacterial structure than the application of inorganic fertilizer only（NPK）, and NPKM treatment was the most important driver for increases in the soil microbial community richness（S） and structural diversity（H）. Overall utilization of carbon sources by soil microbial communities（average well color development, AWCD） and microbial substrate utilization diversity and evenness indices（H＇ and E） indicated that long-term inorganic fertilizer with organic amendments incorporated（NPKM, NPKS） could significantly stimulate soil microbial metabolic activity and functional diversity relative to CK, while no differences of them were found between NPKS and NPK treatments. Principal component analysis（PCA） based on carbon source utilization profiles also showed significant separation of soil microbial community under long-term fertilization regimes and NPKM treatment was significantly separated from the other three treatments primarily according to the higher microbial utilization of carbohydrates, carboxylic acids, polymers, phenolic compounds, and amino acid, while higher utilization of amines/amides differed soil microbial community in NPKS treatment from those in the other three treatments. Redundancy analysis（RDA） indicated that soil organic carbon（SOC） availability, especially soil microbial biomass carbon（Cmic） and Cmic/SOC ratio are the key factors of soil environmental characteristics contributing to the increase of both soil microbial community structure and functional metabolic diversity in the long-term fertilization trial. Our results showed that long-term inorganic fertilizer and swine manure application could significantly improve soil bacterial community structure and soil microbial metabolic activity through the increases in SOC availability, which could provide insights into the sustainable management of China＇s soil resource.展开更多
The aim of this study was to test the impact of Rhizophagus irregularis, an arbuscular mycorrhizal fungus (AMF), on durum wheat growth and soil microbial functionalities in a field inoculation trial conducted in Moroc...The aim of this study was to test the impact of Rhizophagus irregularis, an arbuscular mycorrhizal fungus (AMF), on durum wheat growth and soil microbial functionalities in a field inoculation trial conducted in Morocco. The results showed that i) the R. irregularis inoculum effectively improved wheat growth, ii) wheat growth promotion depended on the soil mycorrhizal infectivity and iii) functional abilities of soil microflora depended on AMF inoculation. This study confirms that field AMF inoculation can be proposed as an effective agronomic practice in wheat production and as a sustainable cultural practice to manage soil biofunctioning. To fully promote inoculation practices, a better knowledge of AMF ecology has to be acquired to better adapt AMF inoculation to environmental conditions, and thus warrant better yields and agricultural sustainability.展开更多
Knowledge of potential anaerobic soil N mineralization is important for nitrogen fertilizer application. Instead of time-consuming laboratory incubation, we attempt to use pedo-transfer functions (PTFs) approach to ge...Knowledge of potential anaerobic soil N mineralization is important for nitrogen fertilizer application. Instead of time-consuming laboratory incubation, we attempt to use pedo-transfer functions (PTFs) approach to get this information. 27 soil samples with various soil depths were collected from paddy field, woodland and tea field in subtropical central China, anaerobically incubated at 35°C for 7 weeks to determine N mineralization, which was fitted by a modified double exponential model with two parameters (the fraction of active N pool (f) and mineralization rate constant (k) for active N pool). The PTFs for parameters were developed from significant soil properties using multiple stepwise regression method. Parameter f (range: 1.59% - 10.4%, mean: 5.2%) was mainly correlated with soil total N (TN), organic C (SOC), sand and silt particle contents (r = -0.59 - 0.69, p k (range: 0.027 - 0.155 d-1, mean: 0.97 d-1) was significantly related to TN, SOC, clay content, C to N ratio and pH (r = -0.6 - 0.71, p f (R2 = 0.72, p TN and pH) for parameter k (R2 = 0.61, p < 0.01). The developed PTFs, integrating various land uses and soil depths, suggest that basic soil properties are helpful for estimation of anaerobic soil N mineralization.展开更多
[Objective] This study aimed to investigation the effects of tranagenic Bt ＋ CpTI cotton cultivation on functional diversity of microbial communities in rhizospbere soils. E Method] By using the Biolog method, a comp...[Objective] This study aimed to investigation the effects of tranagenic Bt ＋ CpTI cotton cultivation on functional diversity of microbial communities in rhizospbere soils. E Method] By using the Biolog method, a comparative study was conducted on the utilization level of single carbon source by microbes in the rhi- zosphere soils of transgenic Bt ＋ CpTI cotton sGK321 and its parental conventional cotton ＇ Shiyuan 321＇ at different growth stages. [ Result ] The results showed that, compared with the parental conventional cotton, the average well-color development （AWCD） value of micmhial communities in rhizospbere soils of transgenie Bt ＋ CpTI cotton were significantly higher （P 〈 O. 05） at seedling stage and budding stage while significantly lower at flower and boll stage and bell opening stage. Shannon-Wiener diversity index （H） and Simpson dominance index （D） of microbial communities in rhlzesphere soils of transgenic cotton and conventional cotton varied with the different growth stages, whereas the Shannon-Wiener evenness index （E） showed no significant difference between transgenie cotton and convention- al cotton at four growth stages. Principal component analysis indicated that the patterns of carbon source utilization by microbial communities in rhizospbere soils were similar among transgenic cotton at seeding stage and flower and boll stage and parental conventional cotton at seeding stage and budding stage, which were also similar between tranagenic cotton at budding stage and parental conventional cotton at flower and boll stage. [ Conclusion] Analysis of different carbon sources indi- cated that the main carbon sources utilized by soil microbes were carbohydrates, amino acids, carboxylie acids and polymers.展开更多
Functional redundancy in soil microbial communities seems to contradict the notion that individual species have distinct metabolic niches in multi-species communities.All soil microbiota have the metabolic capacity fo...Functional redundancy in soil microbial communities seems to contradict the notion that individual species have distinct metabolic niches in multi-species communities.All soil microbiota have the metabolic capacity for"basic"functions(e.g.,respiration and nitrogen and phosphorus cycling),but only a few soil microbiota participate in"rare"functions(e.g.,methanogenesis and mineralization of recalcitrant organic pollutants).The objective of this perspective paper is to use the phylogenetic niche conservatism theory as an explanation for the functional redundancy of soil microbiota.Phylogenetic niche conservatism is defined as the tendency for lineages to retain ancestral functional characteristics through evolutionary time-scales.The present-day soil microbiota is the result of a community assembly process that started when prokaryotes first appeared on Earth.For billions of years,microbiota have retained a highly conserved set of core genes that control the essential redox and biogeochemical reactions for life on Earth.These genes are passed from microbe to microbe,which contributes to functional redundancy in soil microbiota at the planetary scale.The assembly of microbial communities during soil formation is consistent with phylogenetic niche conservatism.Within a specific soil,the heterogeneous matrix provides an infinite number of sets of diverse environmental conditions,i.e.,niches that lead to the divergence of microbial species.The phylogenetic niche conservatism theory predicts that two or more microbial species diverging from the same clade will have an overlap in their niches,implying that they are functionally redundant in some of their metabolic processes.The endogenous genetic factors that constrain the adaptation of individuals and,thus,populations to changing environmental conditions constitute the core process of phylogenetic niche conservatism.Furthermore,the degree of functional redundancy in a particular soil is proportional to the complexity of the considered function.We conclude with a conceptual model that identifies six patterns of functional redundancy in soil microbial communities,consistent with the phylogenetic niche conservatism theory.展开更多
To improve the serious situation of soil degradation in China, tests were carried out to study the improvement effects of Russian Melilotus officinalis on the low base saturation acid soil, the alkaline-saline soil an...To improve the serious situation of soil degradation in China, tests were carried out to study the improvement effects of Russian Melilotus officinalis on the low base saturation acid soil, the alkaline-saline soil and the heavy metal contaminated soil. The results showed that M. officinalis could improve the low base saturation acid soil, increase the salt, alkali content, mineral nutrition and organic nutrient, which indicated that M. officinalis could be planted in the acid soil, and had a significant ecological effect on soil improvement. M. officinalis achieved a remarkable effect on improving the alkaline-saline soil （pH 8.5-9.5） that the soil desalted, dealkalized and had more organic nutrient. Moreover, M. officinalis could improve the heavy metal contaminated soil and had the ability to enrich and transform heavy metal elements, especially Cd and Ni, thereby presenting significant repair effects on soil improvement. Therefore, Russian M. officinalis had multiple-effects on degraded soil improvement, so it is worthy of application and popularization.展开更多
The application of straw and biochar is widely practiced for the improvement of soil fertility.However,its impact on microbial functional profiles,particularly with regard to paddy soils,is not well understood.The aim...The application of straw and biochar is widely practiced for the improvement of soil fertility.However,its impact on microbial functional profiles,particularly with regard to paddy soils,is not well understood.The aim of this study was to investigate the diversity of microbial carbon use patterns in paddy soils amended with straw or straw-derived biochar in a 3-year field experiment in fallow soil and at various development stages of a rice crop(i.e.,tillering and blooming).We applied the community level physiological profiling approach,with 15 substrates(sugars,carboxylic and amino acids,and phenolic acid).In general,straw application resulted in the greatest microbial functional diversity owing to the greater number of available C sources than in control or biochar plots.Biochar amendment promoted the use of α-ketoglutaric acid,the mineralization of which was higher than that of any other substrate.Principal component analyses indicated that microbial functional diversity in the biochar-amended soil was separated from those of the straw-amended and control soils.Redundancy analyses revealed that soil organic carbon content was the most important factor regulating the pattern of microbial carbon utilization.Rhizodeposition and nutrient uptake by rice plants modulated microbial functions in paddy soils and stimulated the microbial use of N-rich substances,such as amino acids.Thus,our results demonstrated that the functional diversity of microorganisms in organic amended paddy soils is affected by both physicochemical properties of amendment and plant growth stage.展开更多
To assess the effects of single and combined pollution of cadmium (Cd) and mercury (Hg) on soil micro-bial community structural and functional diversities, an incubation experiment was conducted, by employing two soil...To assess the effects of single and combined pollution of cadmium (Cd) and mercury (Hg) on soil micro-bial community structural and functional diversities, an incubation experiment was conducted, by employing two soils, namely, the marine sediment silty loam soil and the yellowish-red soil, in which five levels of Cd, Hg and Cd and Hg in combination were added. After being incubated for 56 days, the phospholipid fatty acids (PLFAs) profile and sole carbon source utilization pattern (BIOLOG) of the samples were tested. The results showed that the compo-sition of the microbial communities changed significantly at different levels of metals application. The principal component analyses (PCA) of PLFAs indicated that the structure of the microbial community was also significantly altered with increasing levels of metals, with increasing PLFAs biomarkers for fungi and actinomycetes, and in-creasing ratio of Gram-positive to Gram-negative bacteria. Sole carbon source utilization pattern analysis revealed that single and combined application of Cd and Hg inhibited significantly the functional activity of soil microorgan-isms, the functional diversity indices [Richness (S), Shannon-Wiener indices (H) and Evenness (EH)] were signifi-cantly lower in polluted soils than those in non-polluted soils, which also significantly altered with increasing levels of metals. PCA for the sole carbon source utilization pattern also indicated that the metal contamination could result in a variable soil microbial community. The results revealed that the combination of Cd and Hg had higher toxicity to soil microbial community structural and functional diversities than the individual application of Cd or Hg.展开更多
Ten runoff plots with different planting patterns were established for experimental observation in Yangjichong small watershed of Longli County in Karst region of Guizhou Province. Results show that under the same rai...Ten runoff plots with different planting patterns were established for experimental observation in Yangjichong small watershed of Longli County in Karst region of Guizhou Province. Results show that under the same rainfall condition, shrub land, natural grassland and abandoned land presented the best function of soil and water conservation. The function of soil and water conservation was poor for arbor planting pattern, because the shrub layer, herb layer and forest floor were not formed. Because of no-tillage, surface crust and other effects, the function of soil and water conservation in slope farmland was better than that in runoffplots with arbor planting pattern.展开更多
The negative effect of soil erosion and soil compaction is well documented for the purpose of optimum rangeland functioning, while the impact of rangeland degradation on effective soil depth is seldom quantified. The ...The negative effect of soil erosion and soil compaction is well documented for the purpose of optimum rangeland functioning, while the impact of rangeland degradation on effective soil depth is seldom quantified. The aim of this study was to quantify the response of vegetation cover and soil properties, particularly effective soil depth and soil texture to rangeland degradation. Forty-one farms were sampled in the arid and semi-arid climate of South Africa. Within these farms, data was collected over a vegetation degradation gradient. Results showed a significant decline in relative basal cover (94% ± 15% to 39% ± 17%) and soil depth (90% ± 14% to 73% ± 24%) as rangeland degraded. Soil texture changes over the degradation gradients vary for different homogeneous vegetation types. Indications regarding the loss of a functioning rangeland ecosystem were also demonstrated, using objective long-term relations between rangeland conditions and grazing capacity. The study highlights the importance of sustainable rangeland management practices to reduce the loss in effective soil depth and to ensure the sustainable utilization of the rangeland ecosystem. These results can probably extrapolate to other arid and semi-arid rangelands worldwide.展开更多
基金Supported by Hebei Provincial Social Science Foundation Project in 2012(HB12YJ055)
文摘On the basis of making clear diversity characteristics of soil functions and multiple characteristics of income, this paper points out that the monetization of soil functions based functional maintenance and change decision process can be regarded as a game process of different utilization methods at the background of different functions. The balance of this game process will determine monetary value of soil functions. After understanding money and monetization concepts, it introduces that measurability and exchangeability of soil functions provide objective conditions for monetization of soil functions. Finally, it discusses that usefulness value of soil functions provide basis for monetization of soil functions.
文摘Soil microbial alpha diversity is essential for driving ecosystem functions and processes.However,little is known about the beta-diversity affect community functions.Here,we combine distinct community inocula using the dilution-to-extinction approach with two wheat genotypes to study the effect of microbial diversity loss on rhizosphere community assembly processes,which are related to beta-diversity(between-habitat diversity),and the consequences for ecosystem functions within greenhouse experiment.Compared with alpha-diversity,the bacterial and fungal community beta-diversity are stronger predictors of ecosystem functions(organic matter degradation,phosphorus supply capacity and nitrogen supply capacity),plant genotypes regulated the relationship between microbial diversity and ecosystem functions,with ecosystem functions being significant link to microbial diversity under different wheat genotypes.Loss of microbial diversity decreased the abundance of Bacterial_ASV6(Burkholderia)and increased Fungal_11(Altemaria)within the restored rhizosphere soil.Null modeling analysis showed that the deterministic assembly processes are dominant in bacterial community and fungal high-diversity(alpha-diversity)community,associating with the change of specialized functions(organic matter degradation,phosphorus supply capacity and nitrogen supply capacity)that are correlated with microbial diversity and specific microbial taxa.In addition,these two species were key role for regulating to the network cohesion.Overall,our study pointed out that the regulation of community assembly by microbial diversity loss limits the development of soil ecological functions and weakens the stability of rhizosphere microbial network,highlighting the potential regulatory effect of microbial taxa distribution on microbial community stability and changes of specific ecological functions.
基金supported by the National Natural Science Foundation of China(Nos.41961124004,42207361,and42061124001)。
文摘Partial substitution of synthetic nitrogen(N)with organic fertilizers(PSOF)is of great significance in improving soil ecosystem functions in systems that have deteriorated due to the excessive application of chemical N fertilizer.However,existing studies typically focus on individual soil functions,neglecting the fact that multiple functions occur simultaneously.It remains unclear how PSOF influences multiple soil functions and whether these impacts are related to soil microbial communities.Here,we examined the impacts of partial substitutions(25%–50%)of chemical N fertilizer with organic form(pig manure or municipal sludge)in a vegetable field on soil multifunctionality,by measuring a range of soil functions involving primary production(vegetable yield and quality),nutrient cycling(soil enzyme activities,ammonia volatilization,N leaching,and N runoff),and climate regulation(soil organic carbon sequestration and nitrous oxide emission).We observed that PSOF improved soil multifunctionality,with a 50%substitution of chemical N fertilizer with pig manure being the best management practice;the result was strongly related to the diversities and network complexities of bacteria and fungi.Random forest analysis further revealed that soil multifunctionality was best explained by the bacterial-fungal network complexity,followed by available phosphorus level and bacterial diversity.The PSOF also shifted the composition of bacterial and fungal communities,with increased relative abundances of dominant bacteria phyla,such as Bacteroidetes,Gemmatimonadetes,and Myxococcota,and fungal phyla,such as Basidiomycota and Olpidiomycota.The observed increases in soil multifunctionality were consistent with significant increases in the relative abundances of keystone taxa such as Blastocladiomycota,Chaetomiaceae,and Nocardiopsaceae.Together,these findings indicate that PSOF can enhance interactions within and among microbial communities and that such practices have the potential to improve soil ecosystem multifunctionality and contribute to the development of sustainable agriculture.
基金supported by the Fundamental Research Funds for the Central Universities of China and David Eldridge by the Hermon Slade Foundation.
文摘Trees provide multiple ecosystem services such as carbon sequestration,hydrological regulation and habitat for arboreal animals.However,they are often removed to support agricultural enterprises.Despite the importance of tree remnants,we know relatively little about how soils differ across sites of varying condition.Here,we describe a study where we examined the relative effects of trees,compared with unvegetated interspaces,on soil functions in remnant patches at sites in good and poor condition in two eucalypt communities in an irrigation area in eastern Australia.We found that,in general,carbon and nutrient cycling were relatively greater beneath trees,and in surface soils,but there were no clear trends in relation to site condition.The values of most soil attributes(e.g.,soluble and exchangeable cations,nitrogen,phosphorus)were greater beneath trees,indicating strong fertile island effects in both communities.Overall,our study confirms the importance of trees in remnant patches in agricultural landscapes,particularly those in sites of poor condition.It also suggests that soil processes may still be relatively intact,even in sites in poor condition.Our study reinforces the need to protect trees in remnant woodland reserves to maintain critical ecosystem functions related to nutrient retention.These remnants are important for achieving sustainable management of agricultural systems.
基金supported by the National Natural Science Foundation of China(No.41471395)Shandong Provincial Key Research and Development Program of China(No.2019GSF109008)。
文摘Soil multifunctionality represents a range of soil processes driven by the interactions between soil abiotic and biotic components.As a group of ubiquitous fungi that form mutualistic symbiotic associations with a vast array of terrestrial plants,arbuscular mycorrhizal(AM)fungi may play a critical role in maintaining soil multifunctionality,but the characteristics of their contributions remain to be unraveled.This mini review aims to disentangle the contributions of AM fungi to soil multifunctionality.We provide a framework of concepts about AM fungi making crucial contributions to maintaining multiple soil functions,including primary productivity,nutrient cycling,water regulation and purification,carbon and climate regulation,habitat for biodiversity,disease and pest control,and pollutant degradation and detoxification,via a variety of pathways,particularly contributing to soil and plant health.This review contends that AM fungi,as a keystone component of soil microbiome,can govern soil multifunctionality,ultimately promoting ecosystem services.
基金funded by the Funda??o Agrisus through project code‘PA3010/20’the Coordination for the Improvement of Higher Education Personnel,Brasil,under Finance Code 001。
文摘Managing fertilization in integrated crop-livestock systems(ICLS)during periods of low nutrient export,known as system fertilization,can optimize nutrient use by enhancing the soil's biochemical and physical-hydric properties.However,interdisciplinary studies on processes that improve input utilization in ICLS remain scarce.This study aimed to assess the relationships between the effciencies of different nutrient management strategies in ICLS and pure crop systems(PCS)and the biochemical and physical-hydric quality of soil.Two fertilization strategies(system fertilization and crop fertilization)and two cropping systems(ICLS and PCS)were evaluated in a randomized block design with three replicates.In the PCS,soybean was grown followed by ryegrass as a cover crop.In the ICLS,sheep grazed on the ryegrass.In the crop fertilization,phosphorus and potassium were applied to the soybean planting,and nitrogen was applied in the ryegrass establishment.Nitrogen,phosphorus,and potassium were applied during ryegrass establishment in the system fertilization.Soil quality indexes were calculated using fourteen physical-hydric and biochemical soil indicators,and primary production and nutrient utilization effciency were evaluated.System fertilization in ICLS enhanced the soil functions of water storage and availability for plants,structural stability,and resistance to degradation.System fertilization in ICLS improved the soil quality by 14%over PCS and 13%over crop fertilization in ICLS.Notably,this optimized system yielded the highest primary production.These findings underscore the pivotal role of system fertilization in ICLS to boost food production and enhance soil ecosystem services without increasing the consumption of external fertilizers.They advocate for a strategic shift towards system-level fertilization in integrated systems,and demonstrate for the frst time in ICLS,the delicate balance between nutrient management,soil health,and sustainable productivity.
基金the National Natural Science Foundation of China （40471066） the Knowledge Innovation Program of the Chinese Academy of Sciences （KZCX3-SW-417）.
文摘Changes in soil biological and biochemical properties under different land uses in the subtropical region of China were investigated in order to develop rational cultivation and fertilization management. A small watershed of subtropical region of China was selected for this study. Land uses covered paddy fields, vegetable farming, fruit trees, upland crops, bamboo stands, and forestry. Soil biological and biochemical properties included soil organic C and nutrient contents, mineralization of soil organic C, and soil microbial biomass and community functional diversity. Soil organic C and total N contents, microbial biomass C and N, and respiration intensity under different land uses were changed in the following order： paddy fields （and vegetable farming） 〉 bamboo stands 〉 fruit trccs （and upland）. The top surface （0-15 cm） paddy fields （and vegetable farming） were 76.4 and 80.8% higher in soil organic C and total N contents than fruit trees （and upland） soils, respectively. Subsurface paddy soils （15-30 cm） were 59.8 and 67.3% higher in organic C and total N than upland soils, respectively. Soil microbial C, N and respiration intensity in paddy soils （0-15 cm） were 6.36, 3.63 and 3.20 times those in fruit tree （and upland） soils respectively. Soil microbial metabolic quotient was in the order： fruit trees （and upland） 〉 forestry 〉 paddy fields. Metabolic quotient in paddy soils was only 47.7% of that in fruit tree （and upland） soils. Rates of soil organic C mineralization during incubation changed in the order： paddy fields 〉 bamboo stands 〉 fruit trees （and upland） and soil bacteria population： paddy fields 〉 fruit trees （and upland） 〉 forestry. No significant difference was found for fungi and actinomycetes populations. BIOLOG analysis indicated a changing order of paddy fields 〉 fruit trees （and upland） 〉 forestry in values of the average well cell development （AWCD） and functional diversity indexes of microbial community. Results also showed that the conversion from paddy fields to vegetable farming for 5 years resulted in a dramatic increase in soil available phosphorus content while insignificant changes in soil organic C and total N content due to a large inputs of phosphate fertilizers. This conversion caused 53, 41.5, and 41.3% decreases in soil microbial biomass C, N, and respiration intensity, respectively, while 23.6% increase in metabolic quotient and a decrease in soil organic C mineralization rate. Moreover, soil bacteria and actinomycetes populations were increased slightly, while fungi population increased dramatically. Functional diversity indexes of soil microbial community decreased significantly. It was concluded that land uses in the subtropical region of China strongly affected soil biological and biochemical properties. Soil organic C and nutrient contents, mineralization of organic C and functional diversity of microbial community in paddy fields were higher than those in upland and forestry. Overuse of chemical fertilizers in paddy fields with high fertility might degrade soil biological properties and biochemical function, resulting in deterioration of soil biological quality.
基金supported by the Major Project of China on New Varieties of GMO Cultivation (2012ZX08011-003 and 2014ZX08011-004B)
文摘With the widespread cultivation of transgenic crops, there is increasing concern about unintended effects of these crops on soil environmental quality. In this study, we used the Biolog method and ELISA to evaluate the possible effects of Osr HSA transgenic rice on soil microbial utilization of carbon substrates under field conditions. There were no significant differences in average well-color development(AWCD) values, Shannon–Wiener diversity index(H), Simpson dominance indices(D) and Shannon–Wiener evenness indices(E) of microbial communities in rhizosphere soils at eight samplings between Osr HSA transgenic rice and its non-transgenic counterpart. The main carbon sources utilized by soil microbes were carbohydrates, carboxylic acids, amino acids and polymers. The types,capacities and patterns of carbon source utilization by microbial communities in rhizosphere soils were similar throughout the detection period. We detected no Osr HSA protein in the roots of Osr HSA transgenic rice. We concluded that Osr HSA transgenic rice and the r HSA protein it produced did not alter the functional diversity of microbial communities in the rhizosphere.
基金The National Natural Science Foundation of China as an Outstanding Youth Fund grant (No. 20225722) the National NaturalScience Foundation for the Joint China-Russia Project (No. 20611120015)
文摘Ecological effects of crude oil residues on weed rhizospheres are still vague. The quantitative and diversity changes and metabolic responses of soil-bacterial communities in common dandelion （Taraxacum officinale）, jerusalem artichoke （Silphiurn perfoliatum L.） and evening primrose （A colypha australis L.） rhizospheric soils were thus examined using the method of carbon source utilization. The results indicated that there were various toxic effects of crude oil residues on the growth and reproduction of soil bacteria, but the weed rhizospheres could mitigate the toxic effects. Total heterotrophic counting colony-forming units （CFUs） in the rhizospheric soils were significantly higher than those in the non-rhizospheric soils. The culturable soil-bacterial CFUs in the jerusalem artichoke （S. perfoliatum） rhizosphere polluted with 0.50 kg/pot of crude oil residues were almost twice as much as those with 0.25 kg/pot and without the addition of crude oil residues. The addition of crude oil residues increased the difference in substrate evenness, substrate richness, and substrate diversity between non-rhizospheric and rhizospheric soils of T. officinale and A. australis, but there was no significant （p〉0.05） difference in the Shannon＇s diversity index between non-rhizospheric and rhizospheric soils of S. perfoliatum. The rhizospheric response of weed species to crude oil residues suggested that S. perfoliatum may be a potential weed species for the effective plant-microorganism bioremediation of contaminated soils by crude oil residues.
基金funded by the National Natural Science Foundation of China(NSFC31301843)the National Nonprofit Institute Research Grant of Chinese Academy of Agricultural Sciences(IARRP-202-5)
文摘Exploration of soil environmental characteristics governing soil microbial community structure and activity may improve our understanding of biogeochemical processes and soil quality. The impact of soil environmental characteristics especially organic carbon availability after 15-yr different organic and inorganic fertilizer inputs on soil bacterial community structure and functional metabolic diversity of soil microbial communities were evaluated in a 15-yr fertilizer experiment in Changping County, Beijing, China. The experiment was a wheat-maize rotation system which was established in 1991 including four different fertilizer treatments. These treatments included： a non-amended control（CK）, a commonly used application rate of inorganic fertilizer treatment（NPK）; a commonly used application rate of inorganic fertilizer with swine manure incorporated treatment（NPKM）, and a commonly used application rate of inorganic fertilizer with maize straw incorporated treatment（NPKS）. Denaturing gradient gel electrophoresis（DGGE） of the 16 S r RNA gene was used to determine the bacterial community structure and single carbon source utilization profiles were determined to characterize the microbial community functional metabolic diversity of different fertilizer treatments using Biolog Eco plates. The results indicated that long-term fertilized treatments significantly increased soil bacterial community structure compared to CK. The use of inorganic fertilizer with organic amendments incorporated for long term（NPKM, NPKS） significantly promoted soil bacterial structure than the application of inorganic fertilizer only（NPK）, and NPKM treatment was the most important driver for increases in the soil microbial community richness（S） and structural diversity（H）. Overall utilization of carbon sources by soil microbial communities（average well color development, AWCD） and microbial substrate utilization diversity and evenness indices（H＇ and E） indicated that long-term inorganic fertilizer with organic amendments incorporated（NPKM, NPKS） could significantly stimulate soil microbial metabolic activity and functional diversity relative to CK, while no differences of them were found between NPKS and NPK treatments. Principal component analysis（PCA） based on carbon source utilization profiles also showed significant separation of soil microbial community under long-term fertilization regimes and NPKM treatment was significantly separated from the other three treatments primarily according to the higher microbial utilization of carbohydrates, carboxylic acids, polymers, phenolic compounds, and amino acid, while higher utilization of amines/amides differed soil microbial community in NPKS treatment from those in the other three treatments. Redundancy analysis（RDA） indicated that soil organic carbon（SOC） availability, especially soil microbial biomass carbon（Cmic） and Cmic/SOC ratio are the key factors of soil environmental characteristics contributing to the increase of both soil microbial community structure and functional metabolic diversity in the long-term fertilization trial. Our results showed that long-term inorganic fertilizer and swine manure application could significantly improve soil bacterial community structure and soil microbial metabolic activity through the increases in SOC availability, which could provide insights into the sustainable management of China＇s soil resource.
文摘The aim of this study was to test the impact of Rhizophagus irregularis, an arbuscular mycorrhizal fungus (AMF), on durum wheat growth and soil microbial functionalities in a field inoculation trial conducted in Morocco. The results showed that i) the R. irregularis inoculum effectively improved wheat growth, ii) wheat growth promotion depended on the soil mycorrhizal infectivity and iii) functional abilities of soil microflora depended on AMF inoculation. This study confirms that field AMF inoculation can be proposed as an effective agronomic practice in wheat production and as a sustainable cultural practice to manage soil biofunctioning. To fully promote inoculation practices, a better knowledge of AMF ecology has to be acquired to better adapt AMF inoculation to environmental conditions, and thus warrant better yields and agricultural sustainability.
文摘Knowledge of potential anaerobic soil N mineralization is important for nitrogen fertilizer application. Instead of time-consuming laboratory incubation, we attempt to use pedo-transfer functions (PTFs) approach to get this information. 27 soil samples with various soil depths were collected from paddy field, woodland and tea field in subtropical central China, anaerobically incubated at 35°C for 7 weeks to determine N mineralization, which was fitted by a modified double exponential model with two parameters (the fraction of active N pool (f) and mineralization rate constant (k) for active N pool). The PTFs for parameters were developed from significant soil properties using multiple stepwise regression method. Parameter f (range: 1.59% - 10.4%, mean: 5.2%) was mainly correlated with soil total N (TN), organic C (SOC), sand and silt particle contents (r = -0.59 - 0.69, p k (range: 0.027 - 0.155 d-1, mean: 0.97 d-1) was significantly related to TN, SOC, clay content, C to N ratio and pH (r = -0.6 - 0.71, p f (R2 = 0.72, p TN and pH) for parameter k (R2 = 0.61, p < 0.01). The developed PTFs, integrating various land uses and soil depths, suggest that basic soil properties are helpful for estimation of anaerobic soil N mineralization.
基金Supported by Major Project for Breeding and Cultivation of Novel GM Varieties(2011ZX08012-005,2011ZX08011-002)Dean Fund of Chinese Academy of Agricultural Sciences(201020)
文摘[Objective] This study aimed to investigation the effects of tranagenic Bt ＋ CpTI cotton cultivation on functional diversity of microbial communities in rhizospbere soils. E Method] By using the Biolog method, a comparative study was conducted on the utilization level of single carbon source by microbes in the rhi- zosphere soils of transgenic Bt ＋ CpTI cotton sGK321 and its parental conventional cotton ＇ Shiyuan 321＇ at different growth stages. [ Result ] The results showed that, compared with the parental conventional cotton, the average well-color development （AWCD） value of micmhial communities in rhizospbere soils of transgenie Bt ＋ CpTI cotton were significantly higher （P 〈 O. 05） at seedling stage and budding stage while significantly lower at flower and boll stage and bell opening stage. Shannon-Wiener diversity index （H） and Simpson dominance index （D） of microbial communities in rhlzesphere soils of transgenic cotton and conventional cotton varied with the different growth stages, whereas the Shannon-Wiener evenness index （E） showed no significant difference between transgenie cotton and convention- al cotton at four growth stages. Principal component analysis indicated that the patterns of carbon source utilization by microbial communities in rhizospbere soils were similar among transgenic cotton at seeding stage and flower and boll stage and parental conventional cotton at seeding stage and budding stage, which were also similar between tranagenic cotton at budding stage and parental conventional cotton at flower and boll stage. [ Conclusion] Analysis of different carbon sources indi- cated that the main carbon sources utilized by soil microbes were carbohydrates, amino acids, carboxylie acids and polymers.
基金the Natural Sciences and Engineering Research Council of Canada(NSERC)through Discovery Grant(No.RGPIN-2017-05391).
文摘Functional redundancy in soil microbial communities seems to contradict the notion that individual species have distinct metabolic niches in multi-species communities.All soil microbiota have the metabolic capacity for"basic"functions(e.g.,respiration and nitrogen and phosphorus cycling),but only a few soil microbiota participate in"rare"functions(e.g.,methanogenesis and mineralization of recalcitrant organic pollutants).The objective of this perspective paper is to use the phylogenetic niche conservatism theory as an explanation for the functional redundancy of soil microbiota.Phylogenetic niche conservatism is defined as the tendency for lineages to retain ancestral functional characteristics through evolutionary time-scales.The present-day soil microbiota is the result of a community assembly process that started when prokaryotes first appeared on Earth.For billions of years,microbiota have retained a highly conserved set of core genes that control the essential redox and biogeochemical reactions for life on Earth.These genes are passed from microbe to microbe,which contributes to functional redundancy in soil microbiota at the planetary scale.The assembly of microbial communities during soil formation is consistent with phylogenetic niche conservatism.Within a specific soil,the heterogeneous matrix provides an infinite number of sets of diverse environmental conditions,i.e.,niches that lead to the divergence of microbial species.The phylogenetic niche conservatism theory predicts that two or more microbial species diverging from the same clade will have an overlap in their niches,implying that they are functionally redundant in some of their metabolic processes.The endogenous genetic factors that constrain the adaptation of individuals and,thus,populations to changing environmental conditions constitute the core process of phylogenetic niche conservatism.Furthermore,the degree of functional redundancy in a particular soil is proportional to the complexity of the considered function.We conclude with a conceptual model that identifies six patterns of functional redundancy in soil microbial communities,consistent with the phylogenetic niche conservatism theory.
基金Supported by the Special Fund for Agro-Scientific Research in the Public Interest of China(200903031)the Project of Science and Technology Department of Jilin Province(20070413)
文摘To improve the serious situation of soil degradation in China, tests were carried out to study the improvement effects of Russian Melilotus officinalis on the low base saturation acid soil, the alkaline-saline soil and the heavy metal contaminated soil. The results showed that M. officinalis could improve the low base saturation acid soil, increase the salt, alkali content, mineral nutrition and organic nutrient, which indicated that M. officinalis could be planted in the acid soil, and had a significant ecological effect on soil improvement. M. officinalis achieved a remarkable effect on improving the alkaline-saline soil （pH 8.5-9.5） that the soil desalted, dealkalized and had more organic nutrient. Moreover, M. officinalis could improve the heavy metal contaminated soil and had the ability to enrich and transform heavy metal elements, especially Cd and Ni, thereby presenting significant repair effects on soil improvement. Therefore, Russian M. officinalis had multiple-effects on degraded soil improvement, so it is worthy of application and popularization.
基金financially supported by the National Key Research and Development Program of China(2016YFE0101100)the National Natural Science Foundation of China(41771334,41771337 and 31470629)+2 种基金the Youth Innovation Team Project of the Institute of Subtropical Agriculture,Chinese Academy of Sciences(2017QNCXTD_GTD)the Chinese Academy of Sciences Instrument Function Development Project,the Government Program of Competitive Growth of Kazan Federal University and by the “RUDN University program5–100”
文摘The application of straw and biochar is widely practiced for the improvement of soil fertility.However,its impact on microbial functional profiles,particularly with regard to paddy soils,is not well understood.The aim of this study was to investigate the diversity of microbial carbon use patterns in paddy soils amended with straw or straw-derived biochar in a 3-year field experiment in fallow soil and at various development stages of a rice crop(i.e.,tillering and blooming).We applied the community level physiological profiling approach,with 15 substrates(sugars,carboxylic and amino acids,and phenolic acid).In general,straw application resulted in the greatest microbial functional diversity owing to the greater number of available C sources than in control or biochar plots.Biochar amendment promoted the use of α-ketoglutaric acid,the mineralization of which was higher than that of any other substrate.Principal component analyses indicated that microbial functional diversity in the biochar-amended soil was separated from those of the straw-amended and control soils.Redundancy analyses revealed that soil organic carbon content was the most important factor regulating the pattern of microbial carbon utilization.Rhizodeposition and nutrient uptake by rice plants modulated microbial functions in paddy soils and stimulated the microbial use of N-rich substances,such as amino acids.Thus,our results demonstrated that the functional diversity of microorganisms in organic amended paddy soils is affected by both physicochemical properties of amendment and plant growth stage.
基金supported by the National Natural Science Foundation of China (Project No. 40201026)the State Key Basic Research and Development Plan of China (No. 2002CB410804)
文摘To assess the effects of single and combined pollution of cadmium (Cd) and mercury (Hg) on soil micro-bial community structural and functional diversities, an incubation experiment was conducted, by employing two soils, namely, the marine sediment silty loam soil and the yellowish-red soil, in which five levels of Cd, Hg and Cd and Hg in combination were added. After being incubated for 56 days, the phospholipid fatty acids (PLFAs) profile and sole carbon source utilization pattern (BIOLOG) of the samples were tested. The results showed that the compo-sition of the microbial communities changed significantly at different levels of metals application. The principal component analyses (PCA) of PLFAs indicated that the structure of the microbial community was also significantly altered with increasing levels of metals, with increasing PLFAs biomarkers for fungi and actinomycetes, and in-creasing ratio of Gram-positive to Gram-negative bacteria. Sole carbon source utilization pattern analysis revealed that single and combined application of Cd and Hg inhibited significantly the functional activity of soil microorgan-isms, the functional diversity indices [Richness (S), Shannon-Wiener indices (H) and Evenness (EH)] were signifi-cantly lower in polluted soils than those in non-polluted soils, which also significantly altered with increasing levels of metals. PCA for the sole carbon source utilization pattern also indicated that the metal contamination could result in a variable soil microbial community. The results revealed that the combination of Cd and Hg had higher toxicity to soil microbial community structural and functional diversities than the individual application of Cd or Hg.
文摘Ten runoff plots with different planting patterns were established for experimental observation in Yangjichong small watershed of Longli County in Karst region of Guizhou Province. Results show that under the same rainfall condition, shrub land, natural grassland and abandoned land presented the best function of soil and water conservation. The function of soil and water conservation was poor for arbor planting pattern, because the shrub layer, herb layer and forest floor were not formed. Because of no-tillage, surface crust and other effects, the function of soil and water conservation in slope farmland was better than that in runoffplots with arbor planting pattern.
文摘The negative effect of soil erosion and soil compaction is well documented for the purpose of optimum rangeland functioning, while the impact of rangeland degradation on effective soil depth is seldom quantified. The aim of this study was to quantify the response of vegetation cover and soil properties, particularly effective soil depth and soil texture to rangeland degradation. Forty-one farms were sampled in the arid and semi-arid climate of South Africa. Within these farms, data was collected over a vegetation degradation gradient. Results showed a significant decline in relative basal cover (94% ± 15% to 39% ± 17%) and soil depth (90% ± 14% to 73% ± 24%) as rangeland degraded. Soil texture changes over the degradation gradients vary for different homogeneous vegetation types. Indications regarding the loss of a functioning rangeland ecosystem were also demonstrated, using objective long-term relations between rangeland conditions and grazing capacity. The study highlights the importance of sustainable rangeland management practices to reduce the loss in effective soil depth and to ensure the sustainable utilization of the rangeland ecosystem. These results can probably extrapolate to other arid and semi-arid rangelands worldwide.
