pH对土壤微生物C/P比的影响  

Effect of Soil pH on Soil Microbial Carbon Phosphorus Ratio

作　　者：李春越[1,2,3] 王益[3,4] Philip Brookes 党廷辉[3] 王万忠[3] 

机构地区：[1]陕西师范大学西北国土资源研究中心,中国西安710062 [2]英国洛桑研究所农业与环境中心 [3]西北农林科技大学水土保持研究所,中国陕西杨凌712100 [4]中国科学院地球环境研究所,中国西安710075

出　　处：《中国农业科学》2013年第13期2709-2716,共8页Scientia Agricultura Sinica

基　　金：国家自然科学基金青年项目(41201259);陕西省科学计划自然基金项目(2011JQ5014);陕西师范大学中央高校基本科研业务费专向资金项目(10SZYB27)

摘　　要：【目的】了解pH对土壤微生物量的影响,揭示磷素转化机理及提高磷素利用率的生物调控措施。【方法】以英国洛桑研究所长期定位试验pH梯度土壤为研究对象,研究不同pH下,耕地土壤微生物碳磷比(C/P)及磷素有效性的差异。【结果】微生物C/P比与土壤pH、全碳、无机磷含量以及磷素回收率之间具有一定的相关性。磷素回收率和微生物C/P比随pH的增加而增加,土壤全碳、全磷、C/N和微生物量磷则随pH的增加而减少。土壤呼吸强度随培养时间延长呈线性增加。微生物量碳和ATP呈现出明显的正相关,相关系数高达0.912(n=16)。【结论】pH对于磷素的利用起着重要的作用。微生物C/P比可以作为土壤磷素利用的一个重要指示指标,微生物量C/P比的大小反映土壤微生物对土壤磷有效性的调节作用。[ Objective ] Research on the effects of soil pH on soil microbial biomass is important for providing direct insight into phosphorus transformation mechanism and suggesting biological control to enhance the P utilization rate. [Method] This experiment researched the soil microbial carbon phosphorus ratio and phosphorus availability under different soil pH conditions by testing the soil chemical and biochemical indexes in Rothamsted Research Station, United Kingdom. Two different Bray methods and Olsen method were compared to test soil microbial phosphorus in acid soil. [Result] The results showed that soil microbial carbon phosphorus ratio could be used as a useful indicator to soil phosphorus availability. In general, soil microbial carbon phosphorus ratio had a correlation with soil pH, total carbon, inorganic phosphorus and phosphorus recovery. Soil pH affected soil chemical and soil biochemical properties. Phosphorus recovery and soil microbial carbon phosphorus ratio increased with soil pH. However, soil total carbon, total phosphorus, soil carbon phosphorus ratio and soil microbial phosphorus had a reverse trend. Soil respiration linear increased with the incubation time. [Conclusion] Soil microbial carbon has a significant positive correlation with ATP （r=0.912, n=16）. Bray-1 method is more suitable under acid soil condition for it has a small stand error, despite the result of Olsen and Bray-1 method has a good correlation. Soil pH has some effects on the transformation process from soil microbial phosphorus to inorganic phosphorus.

关 键 词：微生物C P比 pH梯度 长期定位试验 磷素有效性 

分 类 号：S154.3[农业科学—土壤学]