黄土高原森林带土壤养分和微生物量及其生态化学计量变化特征

选择黄土高原森林带自东向西8个地区优势植物的土壤作为研究对象,探究不同经度下土壤养分和土壤微生物生物量生态化学计量特征。结果表明:土壤碳、氮和微生物生物量碳、氮、磷含量随经度整体呈现出先减少后增加的变化趋势,土壤微生物生物量碳氮磷与土壤碳氮之间存在耦合关系,对环境因子的响应具有一致性。土壤磷含量空间分布比较稳定。土壤碳氮比为8左右,土壤有机碳与全氮的空间分布具有一致性。土壤微生物生物量碳氮比为9左右,微生物生物量氮磷比为5左右,反映了土壤微生物生物量碳氮、氮磷的比值较稳定,但土壤微生物生物量碳磷比呈现出先增大后减小的变化趋势。土壤养分及土壤微生物量碳氮磷与土壤水分含量相关性较强。土壤养分与土壤微生物量碳氮磷及其生态化学计量是环境因子综合作用的结果。

Dynamics of Soil Nutrients and Their Ecological Stoichiometry Characteristics Under Different Longitudes in the East-West Forest Belt of the Loess Plateau

This study selected the forest soils from 8 regions under different longitudes in the Loess Plateau as research objects, and explored the soil nutrients, soil microbial biomass and their ecological stoichiometry under different longitudes. The results showed that the contents of soil carbon, nitrogen and microbial biomass carbon, nitrogen and phosphorus overall gave a trend of decreasing first and then increasing with the change of longitudes. There was a coupling relationship between soil microbial biomass carbon, nitrogen and phosphorus and soil carbon and nitrogen, and the response to environmental factors was consistent. The spatial distribution of soil phosphorus content was stable. The soil carbon-nitrogen ratio was around 8, and the spatial distribution of soil organic carbon and total nitrogen was consistent. The soil microbial biomass carbon-nitrogen ratio was about 9, and the microbial biomass nitrogen-phosphorus ratio was about 5, which reflected that the soil microbial biomass carbon-nitrogen and nitrogen-phosphorus ratio were relatively stable, but the soil microbial biomass carbon-phosphorus ratio showed a trend of increasing first and then decreasing. Soil microbial biomass carbon, nitrogen and phosphorus had a strong correlation with soil moisture. Soil nutrients and soil microbial biomass carbon, nitrogen and phosphorus and their ecological stoichiometry were the result of the comprehensive action of environmental factors.