施肥、灌溉及火烧对荒漠草原土壤养分和植物群落特征的影响

Influences of Fertilizer,Irrigation Fire on Community Characteristics and Soil Nutrient in Desert Steppe

通过对内蒙古四子王旗荒漠草原进行施肥、灌溉及火烧处理,研究其对群落特征和土壤养分的影响。结果表明:施氮处理使土壤速效氮含量得到了显著提高(P<0.05),pH值略微降低,但没有达到显著差异水平,对全效养分均无显著影响;灌溉处理提高了土壤pH值,降低了速效氮含量,但都没有达到显著差异水平,对土壤全效养分的影响也无显著差异;火烧处理提高了土壤pH值(P<0.05),降低了有机质含量(P<0.05),全效养分和速效养分均有增加的趋势,但差异不显著。施氮、灌溉和火烧三种处理均降低了群落株丛数(P<0.05)和盖度;施氮和灌溉处理增加了群落高度(P<0.05),火烧处理的影响不显著;施氮和灌溉处理均提高了群落地上生物量(P<0.05),火烧处理的影响不显著。

The experiment investigated influences of fertilizer,irrigation and fire on community characteristics and soil nutrient.The results indicated that fertilization increased the content of available N significantly（P〈0.05）,reduced the pH value slightly,no significantly influences of soil total nutrient;Irrigation reduced the content of available N,increased the pH value,no significantly influences on soil total nutrient;Fire increased pH value,soil total nutrient and available nutrient had increased trend,reduced the content of organic matter;Fertilizer,irrigation and fire reduced the cluster number（P〈0.05）and coverage of communities;Fertilizer and irrigation increased the communities height（P〈0.05）,fire reduced the communities height but no significantly differences;Fertilizer and irrigation increased the above-biomass（P〈0.05）,fire reduced the above-biomass but no significantly differences.