大面积营造集约经营人工林对土壤肥力的影响

摘要

The article analyses the situation and cause of soil fertility degradation in National Afforestation Project(NAP)'s areas,elaborates the countermeasures to prevent the degradation of soil fertility.Based on the monitoring results of soil fertility,the article also discusses the changes of soil fertility under implementation of NAP,and provides a fundamental theory for the environmental protection and plantation establishment in a right way.The results indicate:the project has been carried out for 5 years,the guideline of environmental protection has been strictly followed and the soil fertility has increased slightly.%分析了"世行贷款国家造林项目"(简称NAP)区内人工林地力衰退的现状和原因,阐明了NAP防止地力衰退采取的对策,并根据土壤肥力监测结果分析了NAP实施过程中土壤肥力的变化情况,提出了防止土壤肥力退化的措施.结果表明:项目实施5a来,营造了138.5×104hm2的集约经营人工林,由于严格执行了"环保规程",有效地防止了土壤肥力的退化,土壤肥力不仅没有下降,而且略呈增加的趋势.项目区内热带片和亚热带片的速效氮和有机质略有下降外,土壤中的全氮、速效磷、速效钾、缓效钾等7种养分呈上升趋势.项目区华北-中原、辽东低丘岗地片,土壤中的各种养分含量逐渐增加,其中速效磷、速效钾和代换钙镁增加的速度最快.