[Research advances in trait-based approaches in soil animal community ecology]. / åŸºäºŽåŠŸèƒ½æ€§çŠ¶çš„åœŸå£¤åŠ¨ç‰©ç¾¤è½ç”Ÿæ€å­¦ç ”ç©¶è¿›å±•.

Functional traits are indicators of the responses and adaptation of organisms to environmental changes and cascade to a series of ecosystem functions. The functional traits of soil animals are sensitive to environmental factors and may characterize and predict the changes of ecosystem functions. Multiple dimensions of biodiversity that combing species, phylogenetic, and functional diversity improves the understanding of distribution patterns, community assembly mechanisms and ecosystem functions of soil animals. In this review, we listed the categories of soil animal functional traits and their ecological significance, and summarized current researches on the responses of soil animal communities to environmental changes and the community assembly processes based on trait-based approaches. We proposed to strengthen the study on the impacts of eco-evolution processes of biotic interactions to soil animal functional traits, establish the database of soil animal functional traits, and apply trait-based approaches in the ecological restoration in the future, which would benefit soil biodiversity conservation and sustainability of soil ecosystems.

Evaluating the effects of transgenic Bt rice cultivation on soil stability.

Insecticidal crystal (Cry) proteins produced by genetically modified rice that enter the soil via pollen dispersal, plant residues, and root exudation may disturb soil health. In the present study, we assessed the influences of transgenic Bt rice (i.e., HH1 with Cry1Ab/Cry1Ac) cultivation on the dynamics of soil carbon and nutrients under field conditions during 2013-2016. Transgenic treatments (transgenic Bt rice vs. its parental line (i.e., MH63) of non-Bt rice) have no consistently significant effects on soil property, including available nitrogen, available phosphorus, available potassium, total nitrogen, and total phosphorus, while apparent seasonal changes were observed. Besides, the variations of soil nutrients in the paddy field of transgenic Bt rice did not exceed their resistance capacities, except total organic carbon (TOC; RS (resistance) = 1.51) and total potassium (TK; RS = 2.62) in 2013 and TK (RS = 1.94) in 2014. However, the TOC and soil nutrient of TK in the paddy field of transgenic Bt rice have recovered to the pre-perturbation status after harvest (RL (resilience) = 1.01, F = 0.01, P = 0.91; RL = 0.98, F = 0.34, P = 0.58; RL = 0.99, F = 1.26, P = 0.29). Moreover, the paddy yield of transgenic Bt rice was consistently higher than that of its parental line of non-Bt rice. These results suggested that the cultivation of transgenic Bt rice has no adverse impact on soil stability in terms of soil carbon and nutrients and paddy yield.

[Effects of environmental stresses on soil functional stability under different water management measures in a paddy field]. / 环境胁迫对不同水分管理措施下稻田土壤功能稳定性的影响.

With the increase of global environmental changes and intensive anthropogenic activities, it is important to maintain and improve soil function. Here, we evaluated the effects of environmental stress (i.e., drying, high temperature and the combination of drying and high temperature) on soil functional stability (resistance and resilience) under three kinds of water management mea-sures, which included conventional-flooded cultivation, non-flooded with uncovered cultivation and non-flooded with straw mulching. Results showed that, compared to single environmental stress (drying or high temperature), combined stress led to lower soil fungal biomass, bacterial biomass, basal respiration, and soil functional resistance, and higher contents of dissolved organic carbon (DOC) and NH4+-N after one day treatment of stress. Combined stress significantly decreased soil functional resilience after 56 days treatment of stress. Results from the correlation analysis showed that bacterial and fungal biomass were significantly related to soil resistance and resilience. Different water management measures could regulate the effects of environmental stress on soil functional stability. Non-flooded with straw mulching treatment significantly increased the contents of soil DOC, NH4+-N, fungal biomass and bacterial biomass, resulting in higher soil functional resistance and resilience compared with conventional-flooded cultivation and non-flooded with uncovered cultivation under both single and combined stress. In summary, non-flooded with straw mulching could improve soil functional stability under environmental stress, and it could be a suitable agricultural management for non-continuously flooded rice cultivation under multiple stresses.

[Effects of optimized fertilization on nematode community in greenhouse soils]. / 优化施肥对设施蔬菜地土壤线虫群落的影响.

Excessive fertilization easily leads to the degradation of greenhouse vegetable fields, therefore rational fertilizations are important to maintain the production and sustainable development of vegetable. In this study, two fertilization treatments (optimized fertilization and conventional fertilization, noted as OF and CF, respectively) under continuous tomato-pepper cropping were arranged to investigate soil physicochemical properties, abundance and trophic groups of nematode and vegetable yield. The results showed that OF could maintain soil pH at the relatively higher level and increase the yield of tomato and pepper by 9.0% and 6.9% compared to CF treatment. In contrast to CF, OF increased nematode quantity and the relative abundance of bacterivores, but decreased the relative abundance of fungivores and plant-parasites, more obviously in the growth season of tomato. No obvious differences in plant parasite index, diversity, and richness were observed between CF and OF treatments across all sampling stages of tomato and pepper. Nematode channel ratio ranged from 0.39 to 0.64 in CF treatment, which was significantly lower than that in OF treatment (0.67-0.84), suggesting that the decomposition of food network was dominated by fungi in CF treatment but by bacteria in OF treatment. Based on soil physicochemical properties, nematode groups and vegetable yield, we concluded that optimized fertilization could not only increase vegetable growth but also improve soil ecological environment.

[Effects of interaction between vermicompost and probiotics on soil nronerty, yield and quality of tomato].

In this study, we investigated the effects of two strains of probiotic bacteria (Bacillus megaterium BM and Bacillus amyloliquefaciens BA) combined with chemical fertilizers and vermicompost on the soil property, the yield and quality of tomato. The results showed that under the same nutrient level, vermicompost significantly increased the yield, soluble sugar and protein contents of fruit, the soil pH and available phosphorus when compared with chemical fertilizers. Vermicompost combined with probiotics not only increased the tomato yield, soluble sugar, protein and vitamin C contents, sugar/acid ratio of fruit, and reduced the organic acid and nitrate nitrogen contents of fruit, also increased the soil pH and nitrate nitrogen content, and reduced soil electric conductivity when compared with vermicompost treatment. This improved efficiency was better than that by chemical fertilizers combined with probiotics. For BA and BM applied with chemical fertilizers or vermicompost, both stains had no significant effect on tomato quality. When co-applied with vermicompost, BA and BM showed significant difference in tomato yield. High soil available phosphorus content was determined when BM was combined with chemical fertilizers, while high soil available potassium content was obtained when BA was combined with vermicompost. Our results suggested that probiotics and vermicompost could be used as alternatives of chemical fertilizers in tomato production and soil fertility improvement.

[Influences of water-saved and nitrogen-reduced practice on soil microbial and microfauna assemblage in paddy field].

The resource and environmental problems caused by excessive consumption of water and fertilizer in rice production have recently aroused widespread concern. This study investigated the effects of irrigation modes (conventional irrigation and 25% water-saved irrigation) and different N application rates (conventional high-nitrogen fertilization and 40% nitrogen-reduced fertilization) on microbial and microfauna assemblages at tillering and ripening stages in paddy field. The results showed that compared with conventional irrigation (CF), water-saved irrigation (WS) decreased the soil pH at tillering stage. Soil dissolved organic matter (dissolved organic C and N) and microbial biomass C and N were significantly affected by irrigation, nitrogen fertilizer and their interactions. WS or N-reduced fertilization (LN) decreased the contents of dissolved organic matter; WS increased microbial biomass C but decreased microbial biomass N. Nitrate was significantly higher in WS than CF, while ammonium showed reverse pattern. At tillering stage, the soil microbial biomass from bacteria, fungi, actinomy and protozoa was higher in WS than in CF, but the trend was opposite at ripening stage. There was a significant interation between irrigation and fertilization on soil rotifer numbers and microbial-feeding nematodes. At tillering stage, WS increased the numbers of rotifer and nematode, and also the proportion of bacterial-feeding nematode; LN increased the abundance of rotifer but decreased the abundance of nematode. In summary, soil microbial and microfauna assemblages showed different response to water-saved and nitrogen-reduced agricultural managements, which depended on different crop growth stages, but also the complex interactions of water and nitrogen and between biological groups in food webs.

[Influences of biochar and nitrogen fertilizer on soil nematode assemblage of upland red soil].

The use of biochar as soil remediation amendment has received more and more concerns, but little attention has been paid to its effect on soil fauna. Based on the field experiment in an upland red soil, we studied the influences of different application rates of biochar (0, 10, 20, 30, 40 t · hm⁻²) and nitrogen fertilizer (60, 90, 120 kg N · hm⁻²) on soil basic properties and nematode assemblages during drought and wet periods. Our results showed that the biochar amendment significantly affect soil moisture and pH regardless of drought or wet period. With the increasing of biochar application, soil pH significantly increased, while soil moisture increased first and then decreased. Soil microbial properties (microbial biomass C, microbial biomass N, microbial biomass C/N, basal respiration) were also significantly affected by the application of biochar and N fertilizer. Low doses of biochar could stimulate the microbial activity, while high doses depressed microbial activity. For example, averaged across different N application rates, biochar amendment at less than 30 t · hm⁻² could increase microbial activity in the drought and wet periods. Besides, the effects of biochar also depended on wet or drought period. When the biochar application rate higher than 30 t · hm⁻², the microbial biomass C was significantly higher in the drought period than the control, but no differences were observed in the wet period. On the contrary, microbial biomass N showed a reverse pattern. Dissolved organic matter and mineral N were affected by biochar and N fertilizer significantly in the drought period, however, in the wet period they were only affected by N fertilizer rather than biochar. There was significant interaction between biochar and N fertilizer on soil nematode abundance and nematode trophic composition independent of sampling period. Combined high doses of both biochar and N fertilization promoted soil nematode abundance. Moreover, the biochar amendment increased the proportion of fungivores especially in the drought period, suggesting the biochar was the preferred fungal energy channel in comparison to soil without biochar addition. In summary, complex patterns occurred not only due to the application rate of biochar as well as their interactions with N fertilization but also due to the drought and wet periods. It is, therefore, necessary to consider different ecological factors when evaluating the effects of biochar in future.

[Vermicomposting of different organic materials and three-dimensional excitation emission matrix fluorescence spectroscopic characterization of their dissolved organic matter].

In this experiment, different proportions of the cattle manure, tea-leaf, herb and mushroom residues, were used as food for earthworm (Eisenia fetida) to study the growth of the earth-worm. Then the characteristics and transformation of nutrient content and three-dimensional excitation emission matrix fluorescence (3DEEM) of dissolved organic matter (DOM) during vermistabilization were investigated by means of chemical and spectroscopic methods. The result showed that the mixture of different ratios of cattle manure with herb residue, and cattle manure with tea-leaf were conducive to the growth of earthworm, while the materials compounded with mushroom residue inhibited the growth of earthworm. With the increasing time of verimcomposting, the pH in vermicompost tended to be circumneutral and weakly acidic, and there were increases in electrical conductivity, and the contents of total nitrogen, total phosphorus, available nitrogen, and available phosphorus, while the total potassium and available potassium increased first and then decreased, and the organic matter content decreased. 3DEEM and fluorescence regional integration results indicated that, the fluorescence of protein-like fluorescence peaks declined significantly, while the intensity of humic-like fluorescence peak increased significantly in DOM. Vermicomposting process might change the compositions of DOM with elevated concentrations of humic acid and fulvic acid in the organics. In all, this study suggested the suitability of 3DEEM for monitoring the organics transformation and assessing the maturity in the vermicomposting.

[Responses of soil nematode communities to long-term application of inorganic fertilizers in upland red soil].

Soil biota plays a key role in ecosystem functioning of red soil. Based on the long-term inorganic fertilization field experiment (25-year) in an upland red soil, the impacts of different inorganic fertilization managements, including NPK (nitrogen, phosphorus and potassium fertilizers), NPKCaS (NPK plus gypsum fertilizers), NP (nitrogen and phosphorus fertilizers), NK (nitrogen and potassium fertilizers) and PK (phosphorus and potassium fertilizers), on the assemblage of soil nematodes during the growing period of peanut were investigated. Significant differences among the treatments were observed for total nematode abundance, trophic groups and ecological indices (P < 0.01). The total nematode abundance decreased in the order of PK > NPKCaS > NPK > NP > NK. The total number of nematodes was significantly higher in NPKCaS and PK than in NPK, NP and NK except in May. Plant parasitic nematodes were the dominant trophic group in all treatments excepted in NPKCaS, and their proportion ranged between 38% and 65%. The dominant trophic group in NPKCaS was bacterivores and represented 42.1%. Furthermore, the higher values of maturity index, Wasilewska index and structure index in NPKCaS indicated that the combined application of NPK and gypsum could remarkably relieve soil acidification, resulting in a more mature and stable soil food web structure. While, that of the NK had the opposite effect. In conclusion, our study suggested that the application of both gypsum and phosphate is an effective practice to improve soil quality. Moreover, the analysis of nematode assemblage is relevant to reflect the impact of different inorganic fertilizer on the red soil ecosystem.

[Effects of phytase transgenic corn planting on soil nematode community].

A healthy soil ecosystem is essential for nutrient cycling and energy conversion, and the impact of exogenous genes from genetically modified crops had aroused wide concerns. Phytase transgenic corn (i. e., the inbred line BVLA430101) was issued a bio-safety certificate on 27 September 2009 in China, which could improve the efficiency of feed utilization, reduce environmental pollution caused by animal manure. In this study, the abundance of trophic groups, community structure and ecological indices of soil nematodes were studied over the growing cycle of phytase transgenic corn (ab. transgenic corn) and control conventional parental corn (ab. control corn) in the field. Totally 29 and 26 nematode genera were isolated from transgenic corn and control corn fields, respectively. The abundances of bacterivores and omnivores-predators, the total number of soil nematodes, and the Shannon index (H) were significantly greater under transgenic corn than under control corn, while the opposite trend was found for the relative abundance of herbivores and the maturity index (Sigma MI) of soil nematodes. Repeated-measures analysis of variance (ANOVA) did not detect any significant effects of transgenic corn on the composition and abundance of nematode trophic groups and ecological indices of soil nematodes. Furthermore, the Student-T test showed that the abundances of bacterivores and omnivores-predators and the total number of soil nematodes during the milk-ripe stage were significant higher in the transgenic corn field than in the control corn field. The effects of transgenic corn planting on soil nematodes might be related to the increase in the nitrogen content of field soil under transgenic corn compared to control corn.

[Interactions of straw, nitrogen fertilizer and bacterivorous nematodes on soil labile carbon and nitrogen and greenhouse gas emissions].

A 3 x 2 factorial design of microcosm experiment was conducted to investigate the interactive effects of straw, nitrogen fertilizer and bacterivorous nematodes on soil microbial biomass carbon (C(mic)) and nitrogen (N(mic)), dissolved organic carbon (DOC) and nitrogen (DON), mineral nitrogen (NH(4+)-N and NO(3-)-N), and greenhouse gas (CO2, N2O and CH4) emissions. Results showed that straw amendment remarkably increased the numbers of bacterivorous nematodes and the contents of Cmic and Nmic, but Cmic and Nmic decreased with the increasing dose of nitrogen fertilization. The effects of bacterivorous nematodes strongly depended on either straw or nitrogen fertilization. The interactions of straw, nitrogen fertilization and bacterivorous nematodes on soil DOC, DON and mineral nitrogen were strong. Straw and nitrogen fertilization increased DOC and mineral nitrogen contents, but their influences on DON depended on the bacterivorous nematodes. The DOC and mineral nitrogen were negatively and positively influenced by the bacterivorous nematodes, re- spectively. Straw significantly promoted CO2 and N2O emissions but inhibited CH4 emission, while interactions between nematodes and nitrogen fertilization on emissions of greenhouse gases were obvious. In the presence of straw, nematodes increased cumulative CO2 emissions with low nitrogen fertilization, but decreased CO2 and N2O emissions with high nitrogen fertilization on the 56th day after incubation. In summary, mechanical understanding the soil ecological process would inevitably needs to consider the roles of soil microfauna.

[Effects of nitrogen fertilization and straw amendment on soil microbial biomass and soil functions after heat stress].

A 60-day incubation experiment was conducted to study the effects of nitrogen fertilization (N), rice straw amendment (R), and their combination (RN) on the changes of soil microbial biomass and soil functions (basal respiration, substrate-induced respiration, and straw decomposition) after heat stress (40 degrees C for 18 h). Heat stress tended to promote the soil microbial biomass and soil functions, but the effects were weak and transient. Either with or without heating, treatment R and especially RN could greatly stimulate soil microbial biomass, basal respiration, substrate-induced respiration and straw decomposition, as compared to no straw amendment and with nitrogen fertilization alone, but the parameters in treatment N had less change, and even, presented a decreasing trend. It was suggested that straw amendment and its combination with nitrogen fertilization could improve soil functions in natural conditions or after environmental stress.

[Effects of dissolved organic matter on copper absorption by ryegrass].

In this study, dissolved organic matter (DOM) was extracted from earthworm casts and from the cattle manure with which the earthworms were fed, and a water culture experiment was conducted to study the effects of the DOM on the copper (Cu2+) absorption by ryegrass in the presence of different concentration Cu2+ (0, 5 and 10 mg x L(-1)). With the increasing concentration of Cu2+ in the medium, there was a gradual decrease in the dry mass of ryegrass shoots and roots and in the root length, surface area, volume, and tip number. In the presence of medium Cu2+, DOM increased the biomass of shoots and roots and the root length, surface area, volume, and tip number significantly. DOM reduced the Cu2+ concentration in roots, promoted the Cu2+ translocation from roots to shoots, and significantly increased the Cu2+ accumulation in shoots. The DOM from earthworm casts had better effects than that from cattle manure, and high concentration DOM had better effects than low concentration DOM.

[Effects of transgenic Bt rice on soil dissolved organic carbon and nitrogen contents and microbiological properties].

A two-year field experiment (2009 and 2010) was conducted to evaluate the effects of three transgenic Bt rice lines (KMD, HH1, and BtSY63) and their non-Bt lines (XSD, MH63, and SY63) on soil dissolved organic carbon (DOC) and nitrogen (DON) and microbiological properties. All the measured indices changed significantly with sampling time. Comparing with their corresponding non-Bt lines, the test transgenic Bt lines had little effects on the soil DOC, DON, and microbial biomass nitrogen (MBN). The transgenic Bt lines had significant effects on the soil microbial biomass carbon (MBC), basal respiration (BR), and microbial metabolic quotient (qCO2) in certain periods of time in the first year, but no effects in the second year. Among the soils planted with the three non-Bt rice lines, no difference was observed in the DOC, DON, and microbiological properties, whereas in the soil planted with BtSY63, the MBC and BR were significantly higher, but the qCO2 was significantly lower, as compared with those in the soils planted with KMD and HH1. In sum, two years' planting transgenic Bt rice had little effects on the soil DOC, DON, and microbiological properties, but the differences of soil microbiological properties induced by the planting of different transgenic Bt rice lines were larger than those induced by the planting of different non-Bt lines, implying that long term monitoring would help to reveal the effects of transgenic Bt rice on the structure and function of soil ecosystem.

[Characteristics of soil nematode communities in coastal wetlands with different vegetation types].

An investigation was conducted on the characteristics of soil nematode communities in different vegetation belts (Spartina alterniflora belt, Sa; Suaeda glauca belt, Sg; bare land, B1; Phragmites australis belt, Pa; and wheat land, Wl) of Yancheng Wetland Reserve, Jiangsu Province of East China. A total of 39 genera and 20 families of soil nematodes were identified, and the individuals of dominant genera and common genera occupied more than 90% of the total. The total number of the nematodes differed remarkably with vegetation belts, ranged from 79 to 449 individuals per 100 grams of dry soil. Wheat land had the highest number of soil nematodes, while bare land had the lowest one. The nematode ecological indices responded differently to the vegetation belts. The Shannon index (H) and evenness index (J) decreased in the order of Pa > Sg > Wl > Sa > Bl, and the dominance index (lambda) was in the order of Bl > Sa > Wl > Sg > Pa, suggesting that the diversity and stability of the nematode community in bare land were lower than those in the other vegetation belts, and the nematode community in the bare land tended to be simplified. The maturity index (MI) was higher in uncultivated vegetation belts than in wheat land, suggesting that the wheat land was disturbed obviously. The nematode community structure differed significantly with vegetation belts, and the main contributing species in different vegetation belts also differed. There existed significant correlations between the soil physical and chemical characteristics and the nematode numbers, trophic groups, and ecological indices. Our results demonstrated that the changes of soil nematode community structure could be used as an indicator well reflecting the diversity of vegetation belt habitat, and an important bio-indicator of coastal wetland ecosystem.

[Effects of two years planting transgenic Bt rice (BtSY63) on soil nematode community].

A two-year field experiment was conducted to evaluate the effects of planting transgenic Bt rice (BtSY63) and its near-isogenic non-Bt rice (SY63) on the soil nematode abundance, trophic group composition, ecological indices, and community structure. With the planting of BtSY63 and SY63, the soil nematode abundance changed obviously with sampling time, but had no significant difference between planting BtSY63 and SY63. Only at specific sampling time, the percentage of omnivore-predators and the Shannon diversity index of nematode community under the planting of BtSY63 were significantly higher than those under the planting of SY63. The non-metric multidimensional scaling (nMDS) of nematode community revealed that no significant difference was observed in the nematode community composition between planting BtSY63 and SY63 across all sampling times. In conclusion, two years planting BtSY63 had no deleterious effects on the soil nematode community.

[Control effects of Ricinus communis extracts on Meloidogyne incognita].

Toxicity test and pot experiment were conducted to study the nematocidal activity and control effects of Ricinus communis extracts on Meloidogyne incognita. The results showed that both the ricinine and the R. communis water extracts had high nematocidal activity. The ricinine at concentration 2 g x L(-1) and treated for 48 hours had the strongest nematocidal activity, leading to 91.5% of corrected mortality of M. incognita and with the LC50 being 0.6 g x L(-1), whereas the R. communis water extracts at concentration 100 g x L(-1) and treated for 48 hours had the strongest nematocidal activity, which led to 83.5% of corrected mortality of M. incognita, and the LC50 was 18.3 g x L(-1). With the inoculation of M. incognita treated with ricinine, R. communis water extracts, and R. communis leaf powder, respectively, on tomato seedlings, the mean number of plant root-knots was 17.6 +/- 1.7, 20.6 +/- 1.5 and 22.8 +/- 3.7, respectively, being significantly lower than the control (37.4 +/- 2.3), and the root length increased by 46.8%, 34.5% and 33.8%, and the plant height increased by 33.5%, 22.6% and 15.8%, and the fresh mass increased by 41.4%, 18.9% and 10.1%, respectively, compared with the control. All the results suggested that R. communis extracts could mitigate the harm of M. incognita, and had obvious effects on potted tomato against M. incognita.

[Influence of fungi-feeding nematodes on soil functional stability under heat or copper stress].

In a microcosm experiment, the effects of the interaction between soil fungi-feeding nematodes and microorganisms on the soil functional stability under persistent stress of CuSO4 or transient stress of heating to 40 degrees C for 18 h were studied, with the short-term decomposition of barley leaf powder as a representative of soil function. The results showed that whether the stress existed or not, inoculation of fungi-feeding nematodes could enhance soil basal respiration, an overall indicator of soil microbial activity. Under copper stress, the soil basal respiration after the inoculation increased significantly during the period from the 8th day to the end of the experiment (P < 0.05); while under heat stress, the promotion effect of the inoculation was only significant at the 8th day of the experiment, suggesting that the influence of fungi-feeding nematodes on soil microorganisms varied with stress type. Under the two stresses, inoculation of fungi-feeding nematodes had no influence on the resistance of soil function but could promote its recovery, and the soil fungal biomass in the late period of the experiment was lower in the treatment of inoculation than in CK, indicating that under stress condition, fungi-feeding nematodes depressed the growth and development of soil fungi, and possibly, indirectly promoted bacterial development.

[Effects of earthworm inoculation and straw amendment on soil microflora and microbial activity in Cu contaminated soil].

In this paper, the dynamics of microflora and microbial activity in soil added with 0, 100, 200 and 400 mg x kg(-1) of Cu2+ were studied under effects of inoculating earthworm and applying straw. Four treatments were installed, i.e., CK, surface application of straw (M), inoculation of earthworm (E), and M plus E (ME). The results showed that Cu contamination had inhibitory effect on soil bacteria and actinomycetes, but no effect on soil fungi. Straw amendment increased soil fungi significantly, while earthworm inoculation could increase the numbers of soil bacteria and actinomycetes significantly but had little effect on soil fungi. When the Cu concentration was higher than 200 mg x kg(-1, soil microbial biomass carbon was depressed, but earthworm inoculation and straw amendment could enhance it, with most significant effect under the combination of these two treatments. Earthworm inoculation and straw amendment could enhance soil basal respiration markedly. When the Cu concentration was lower than 200 mg x kg(-1), treatment M had the highest soil basal respiration, being about 3.06-5.58 times higher than that of CK, while at Cu > or =200 mg x kg(-1), soil qCO2 followed the sequence of ME > E > M > CK. Treatments M and E had no effects on soil NH4+ -N. As for soil NO3- -N, treatment E could increase it significantly, but treatment M was in adverse. Treatment ME induced the lowest soil NO3- -N. In a definite degree, earthworm inoculation and straw amendment could mitigate the negative impact of Cu contamination on soil microflora and microbial activity.