Soil organic carbon （SOC）, soil microbial biomass carbon （SMBC） and SMBC quotient （SMBC/SOC, qSMBC） are key indexes of soil biological fertility because of the relationship to soil nutrition supply capacity. Yet...Soil organic carbon （SOC）, soil microbial biomass carbon （SMBC） and SMBC quotient （SMBC/SOC, qSMBC） are key indexes of soil biological fertility because of the relationship to soil nutrition supply capacity. Yet it remains unknown how these three indexes change, which limits our understanding about how soil respond to different fertilization practices. Based on a 22-yr （1990-2011） long-term fertilization experiment in northwest China, we investigated the dynamics of SMBC and qSMBC during the growing period of winter wheat, the relationships between the SMBC, qSMBC, soil organic carbon （SOC） concentrations, the carbon input and grain yield of wheat as well. Fertilization treatments were 1） nonfertilization （control）; 2） chemical nitrogen plus phosphate plus potassium （NPK）; 3） NPK plus animal manure （NPKM）; 4） double NPKM （hNPKM） and 5） NPK plus straw （NPKS）. Results showed that the SMBC and qSMBC were significantly different among returning, jointing, flowering and harvest stages of wheat under long-term fertilization. And the largest values were observed in the flowering stage. Values for SMBC and qSMBC ranged from 37.5 to 106.0 mg kg1 and 0.41 to 0.61%, respectively. The mean value rank of SMBC during the whole growing period of wheat was hNPKM〉NPK_M〉NPKS〉CK〉NPK. But there were no statistically significant differences between hNPKM and NPKM, or between CK and NPK. The order for qSMBC was NPKS〉NPKM〉CK〉hNPKM〉NPK. These results indicated that NPKS significantly increased the ratio of SMBC to SOC, i.e., qSMBC, compared with NPK fertilizer or other two NPKM fertilizations. Significant linear relationships were observed between the annual carbon input and SOC （P〈0.01） or SMBC （P〈0.05）, and between the relative grain yield of wheat and the SOC content as well （P〈0.05）. But the qSMBC was not correlated with the annual carbon input. It is thus obvious that the combination of manure, straw with mineral fertilizer may be benefit to increase SOC and improve soil quality than using only mineral fertilizer.展开更多
As per randomized block design, the research had different fertilizer treatments, and the organic matter, respiration, enzyme activity and microbial carbon and nitrogen in reclaimed soil were studied. Fertilization sc...As per randomized block design, the research had different fertilizer treatments, and the organic matter, respiration, enzyme activity and microbial carbon and nitrogen in reclaimed soil were studied. Fertilization schemes were as follows： The treatment without fertilizers（CK）, the treatment with chemical fertilizers（C）, the treatment with chemical fertilizers and bacterial fertilizer（CB）, the treatment with organic fertilizer and chemical fertilizers（CM）, and the treatment with chemical fertilizers, organic fertilizer and bacterial fertilizer（CMB）. The results showed： Four fertilization treatments could improve the content of soil organic matter. CMB, CM and CB could significantly improve the soil respiration. Organic fertilizer and fertilizer could significantly improve soil enzyme activity, In different growth stages the CMB treatment had highest urease and phosphatase.The most significant in the treatment content of sucrose was CM. Organic fertilizer and microbial fertilizer can significantly improve the microbial carbon and nitrogen in soil. For the microbial biomass carbon, the CMB treatment increased by 11%-34% than CB treatment, and 35%-63% than C treatment. In terms of microbial nitrogen CMB, CM respectively increased by 31%-51% than CB treatment, and 52%-100% compared with C. In the process of land reclamation, we should combine the organic fertilizer, microbial fertilizer and inorganic fertilizer. Only in this way can soil biological activity be accelerated, soil microbial environment improved, and the ripening increased soil nutrient and soil cultivation be enhanced.展开更多
Like straw, biochar incorporation can influence soil microorganisms and enzyme activities and soil carbon(C) responses;however,few studies have compared the various effects of straw and biochar and the underlying mech...Like straw, biochar incorporation can influence soil microorganisms and enzyme activities and soil carbon(C) responses;however,few studies have compared the various effects of straw and biochar and the underlying mechanisms. An experiment was performed to study the changes in soil respiration(SR) and soil organic C(SOC) fluxes in response to the incorporation of three kinds of straw(reed, smooth cordgrass, and rice) and their pyrolyzed products(biochars) at Chongming Island, China. In addition, the microbial activity and community structure of some amended soils were also analyzed to clarify the mechanisms of these responses. The results showed that all biochar incorporation(BC) induced lower SR than the corresponding unpyrolyzed straw incorporation(ST), and the average SR in the soils following BC and ST during the experimental periods was 21.69 and 65.32 μmol CO2 m^-2s^-1, respectively.Furthermore, the average SOC content was 16.97 g kg-1 following BC, which was higher than that(13.71 g kg-1) following ST,indicating that compared to ST, BC was a low-C strategy, even after accounting for the C loss during biochar production. Among the BC treatments, reed-BC induced the lowest SR(17.04 μmol CO2 m^-2s^-1), whereas smooth cordgrass-BC induced the highest SR(27.02 μmol CO2 m^-2s^-1). Furthermore, in contrast with ST, BC significantly increased the abundance of some bacteria with poorer mineralization or better humification ability, which led to lower SR. The lower easily oxidizable C(EOC) and higher total C contents of biochars induced lower SR and higher SOC in the soil following BC compared to that following ST. Among the BC treatments,the higher total nitrogen content of rice biochar led to significantly higher soil microbial biomass, and the lower EOC content of reed biochar led to lower soil microbial activity and SR.展开更多
【目的】土壤微生物生物量是土壤生物肥力的重要指标,是土壤养分重要的周转库。探讨不同气候和施肥条件下土壤微生物生物量(生物量碳、氮)的特征及容量,对于深刻认识土壤微生物生物量的影响因素及提高土壤生物肥力具有重要意义。【方法...【目的】土壤微生物生物量是土壤生物肥力的重要指标,是土壤养分重要的周转库。探讨不同气候和施肥条件下土壤微生物生物量(生物量碳、氮)的特征及容量,对于深刻认识土壤微生物生物量的影响因素及提高土壤生物肥力具有重要意义。【方法】本研究从中国知网、万方和web of Science 3个文献数据库,以"土壤微生物生物量"、"中国农田"和"长期施肥"为关键词,共收集目标文献42篇,包括458组含土壤有机碳(SOC)与土壤微生物生物量碳(SMBC)和414组含土壤全氮(TN)与土壤微生物生物量氮(SMBN)的数据集,涵盖了4种气候下的2类施肥条件(施有机肥:单施或配施,+OM;不施有机肥:无肥和化肥,-OM)。土壤微生物熵(SMBC/SOC)和SMBN/TN的中值差异性均采用Kruskal-Wallis H单向显著性检验(P<0.05),容量分析采用界限分析方法。【结果】统计分析结果表明,不同施肥处理下,SMBC与SOC和SMBN与TN之间均存在显著线性正相关关系(P<0.01),长期施用有机肥条件下,土壤微生物生物量碳、氮对土壤有机碳和全氮增加的响应系数分别为24.77和30.27,显著高于化肥或不施肥条件(分别为19.88和19.86)(P<0.05)。界限分析结果显示,不同施肥措施下SMBC对SOC增加响应的最大值为33.45—36.00,SMBN对TN的最大响应系数为45.45—49.79,当前条件下SMBC和SMBN还有37.99%和49.66%的提升空间。不同气候条件下SMBC/SOC和SMBN/TN均存在显著差异(P<0.05),其中,中温带半干旱半湿润区SMBC/SOC的中值最高为2.73%,其次为亚热带湿润区(2.45%)和暖温带湿润区(2.31%),中温带湿润区最低为1.48%;SMBN/TN的中值大小顺序为:暖温带湿润区(4.72%)>中温带半干旱半湿润区(3.50%)>亚热带湿润区(2.99%)>中温带湿润区(1.80%)。不同施肥条件下SMBC/SOC和SMBN/TN的变化范围分别为0.35%—6.50%和0.50%—9.72%,但其中值并无显著差异(P>0.05)。对于同一气候条件不同施肥措施而言,仅在中温带湿润区,施有机肥处理对微生物量碳(氮)占总有机碳(氮)的比例有显著影响(P<0.05)。【结论】气候对土壤微生物生物量碳、氮所占比例具有显著影响,不同施肥模式虽然不能显著改变微生物生物量碳、氮的比例,但有机肥的施用对微生物生物量碳、氮的提升效果显著高于化肥或不施肥,该结果对于土壤生物肥力的调控有重要指导意义。展开更多
基金the National Natural Science Foundation of China (41061035, 41371247)the Project of Aid of Science and Technology in Xinjiang, China (201191140) for providing funding for this work
文摘Soil organic carbon （SOC）, soil microbial biomass carbon （SMBC） and SMBC quotient （SMBC/SOC, qSMBC） are key indexes of soil biological fertility because of the relationship to soil nutrition supply capacity. Yet it remains unknown how these three indexes change, which limits our understanding about how soil respond to different fertilization practices. Based on a 22-yr （1990-2011） long-term fertilization experiment in northwest China, we investigated the dynamics of SMBC and qSMBC during the growing period of winter wheat, the relationships between the SMBC, qSMBC, soil organic carbon （SOC） concentrations, the carbon input and grain yield of wheat as well. Fertilization treatments were 1） nonfertilization （control）; 2） chemical nitrogen plus phosphate plus potassium （NPK）; 3） NPK plus animal manure （NPKM）; 4） double NPKM （hNPKM） and 5） NPK plus straw （NPKS）. Results showed that the SMBC and qSMBC were significantly different among returning, jointing, flowering and harvest stages of wheat under long-term fertilization. And the largest values were observed in the flowering stage. Values for SMBC and qSMBC ranged from 37.5 to 106.0 mg kg1 and 0.41 to 0.61%, respectively. The mean value rank of SMBC during the whole growing period of wheat was hNPKM〉NPK_M〉NPKS〉CK〉NPK. But there were no statistically significant differences between hNPKM and NPKM, or between CK and NPK. The order for qSMBC was NPKS〉NPKM〉CK〉hNPKM〉NPK. These results indicated that NPKS significantly increased the ratio of SMBC to SOC, i.e., qSMBC, compared with NPK fertilizer or other two NPKM fertilizations. Significant linear relationships were observed between the annual carbon input and SOC （P〈0.01） or SMBC （P〈0.05）, and between the relative grain yield of wheat and the SOC content as well （P〈0.05）. But the qSMBC was not correlated with the annual carbon input. It is thus obvious that the combination of manure, straw with mineral fertilizer may be benefit to increase SOC and improve soil quality than using only mineral fertilizer.
基金Supported by Natural Science Foundation of Shanxi Province(2014011001-4)~~
文摘As per randomized block design, the research had different fertilizer treatments, and the organic matter, respiration, enzyme activity and microbial carbon and nitrogen in reclaimed soil were studied. Fertilization schemes were as follows： The treatment without fertilizers（CK）, the treatment with chemical fertilizers（C）, the treatment with chemical fertilizers and bacterial fertilizer（CB）, the treatment with organic fertilizer and chemical fertilizers（CM）, and the treatment with chemical fertilizers, organic fertilizer and bacterial fertilizer（CMB）. The results showed： Four fertilization treatments could improve the content of soil organic matter. CMB, CM and CB could significantly improve the soil respiration. Organic fertilizer and fertilizer could significantly improve soil enzyme activity, In different growth stages the CMB treatment had highest urease and phosphatase.The most significant in the treatment content of sucrose was CM. Organic fertilizer and microbial fertilizer can significantly improve the microbial carbon and nitrogen in soil. For the microbial biomass carbon, the CMB treatment increased by 11%-34% than CB treatment, and 35%-63% than C treatment. In terms of microbial nitrogen CMB, CM respectively increased by 31%-51% than CB treatment, and 52%-100% compared with C. In the process of land reclamation, we should combine the organic fertilizer, microbial fertilizer and inorganic fertilizer. Only in this way can soil biological activity be accelerated, soil microbial environment improved, and the ripening increased soil nutrient and soil cultivation be enhanced.
基金financially supported by the National Natural Science Foundation of China(No.215-77101)the National Key R&D Program of China(No.2017YFC0506004)the Science and Technology Developmental Fund Projects of Pudong District,China(No.PKJ2015-C11)
文摘Like straw, biochar incorporation can influence soil microorganisms and enzyme activities and soil carbon(C) responses;however,few studies have compared the various effects of straw and biochar and the underlying mechanisms. An experiment was performed to study the changes in soil respiration(SR) and soil organic C(SOC) fluxes in response to the incorporation of three kinds of straw(reed, smooth cordgrass, and rice) and their pyrolyzed products(biochars) at Chongming Island, China. In addition, the microbial activity and community structure of some amended soils were also analyzed to clarify the mechanisms of these responses. The results showed that all biochar incorporation(BC) induced lower SR than the corresponding unpyrolyzed straw incorporation(ST), and the average SR in the soils following BC and ST during the experimental periods was 21.69 and 65.32 μmol CO2 m^-2s^-1, respectively.Furthermore, the average SOC content was 16.97 g kg-1 following BC, which was higher than that(13.71 g kg-1) following ST,indicating that compared to ST, BC was a low-C strategy, even after accounting for the C loss during biochar production. Among the BC treatments, reed-BC induced the lowest SR(17.04 μmol CO2 m^-2s^-1), whereas smooth cordgrass-BC induced the highest SR(27.02 μmol CO2 m^-2s^-1). Furthermore, in contrast with ST, BC significantly increased the abundance of some bacteria with poorer mineralization or better humification ability, which led to lower SR. The lower easily oxidizable C(EOC) and higher total C contents of biochars induced lower SR and higher SOC in the soil following BC compared to that following ST. Among the BC treatments,the higher total nitrogen content of rice biochar led to significantly higher soil microbial biomass, and the lower EOC content of reed biochar led to lower soil microbial activity and SR.
文摘【目的】土壤微生物生物量是土壤生物肥力的重要指标,是土壤养分重要的周转库。探讨不同气候和施肥条件下土壤微生物生物量(生物量碳、氮)的特征及容量,对于深刻认识土壤微生物生物量的影响因素及提高土壤生物肥力具有重要意义。【方法】本研究从中国知网、万方和web of Science 3个文献数据库,以"土壤微生物生物量"、"中国农田"和"长期施肥"为关键词,共收集目标文献42篇,包括458组含土壤有机碳(SOC)与土壤微生物生物量碳(SMBC)和414组含土壤全氮(TN)与土壤微生物生物量氮(SMBN)的数据集,涵盖了4种气候下的2类施肥条件(施有机肥:单施或配施,+OM;不施有机肥:无肥和化肥,-OM)。土壤微生物熵(SMBC/SOC)和SMBN/TN的中值差异性均采用Kruskal-Wallis H单向显著性检验(P<0.05),容量分析采用界限分析方法。【结果】统计分析结果表明,不同施肥处理下,SMBC与SOC和SMBN与TN之间均存在显著线性正相关关系(P<0.01),长期施用有机肥条件下,土壤微生物生物量碳、氮对土壤有机碳和全氮增加的响应系数分别为24.77和30.27,显著高于化肥或不施肥条件(分别为19.88和19.86)(P<0.05)。界限分析结果显示,不同施肥措施下SMBC对SOC增加响应的最大值为33.45—36.00,SMBN对TN的最大响应系数为45.45—49.79,当前条件下SMBC和SMBN还有37.99%和49.66%的提升空间。不同气候条件下SMBC/SOC和SMBN/TN均存在显著差异(P<0.05),其中,中温带半干旱半湿润区SMBC/SOC的中值最高为2.73%,其次为亚热带湿润区(2.45%)和暖温带湿润区(2.31%),中温带湿润区最低为1.48%;SMBN/TN的中值大小顺序为:暖温带湿润区(4.72%)>中温带半干旱半湿润区(3.50%)>亚热带湿润区(2.99%)>中温带湿润区(1.80%)。不同施肥条件下SMBC/SOC和SMBN/TN的变化范围分别为0.35%—6.50%和0.50%—9.72%,但其中值并无显著差异(P>0.05)。对于同一气候条件不同施肥措施而言,仅在中温带湿润区,施有机肥处理对微生物量碳(氮)占总有机碳(氮)的比例有显著影响(P<0.05)。【结论】气候对土壤微生物生物量碳、氮所占比例具有显著影响,不同施肥模式虽然不能显著改变微生物生物量碳、氮的比例,但有机肥的施用对微生物生物量碳、氮的提升效果显著高于化肥或不施肥,该结果对于土壤生物肥力的调控有重要指导意义。
