不同降雨量下人工重建林土壤性状及微生物特性比较

分析和比较了甘肃省中部典型黄土丘陵区不同降雨量下人工重建林土壤性状及微生物特性.结果表明:随降水量的增加,土壤含水量升高,pH值变化不明显;土壤有机碳、全氮、微生物量碳、微生物量氮含量均表现为以400 mm降水量为分界线,降水量≥400 mm样地的含量显著高于降水量<400 mm样地(p<0.05);降水量为500 mm样地的全磷、速效磷、速效钾含量及土壤微生物呼吸最高,但土壤微生物呼吸熵为200 mm降水量样地最高;微生物熵变化不显著.相关性分析表明,不同降水量梯度下,土壤理化性质与微生物特性之间存在不同程度的相关性.

Soil Physicochemical Properties and Microbial Characteristics in Artificial Reconstructed Forests with Different Quatity of Precipitation in the Loess Hilly Region of China

Responses of soil physicochemical properties and microbial characteristics to precipitation were determined and analyzed under artificial reconstructed forest and grassland in a loess hilly region of Gansu, China. The results showed that soil water content increased with increasing precipitation, while pH value had no significant differences between precipitation treatments; precipitation of 400 mm was as a "dividing line". The content of soil organic carbon, total nitrogen, soil microbial biomass carbon and soil microbial biomass nitrogen of high precipitation zone (≥400 mm) were significance higher than that in the low precipitation zone (<400 mm). The highest content of total phosphorus, available potassium, available phosphorus and microbial respiration were in the plots with 500 mm precipitation, while the highest metabolic quotient for CO₂ was in the plots with 200mm precipitation, and microbial quotient had no significance difference with precipitation. Meanwhile the result indicated that there was significant correlation between soil physicochemical and microbial characteristics in different precipitation plots.