【摘要】 揭示不同砍伐频率对森林土壤养分库和氮周转的影响,对于理解森林养分循环的干扰响应具有重要意义。本研究以浙江天童常绿阔叶林为对象,选择了3个具有不同砍伐频率的群落比对组,分析各组内土壤有机碳和氮磷养分库,以及氮素矿化、硝化速率的变化。结果表明:3组群落中,重复砍伐群落的土壤总氮和总有机碳储量显著减小(P<0.05),而土壤总磷、铵态氮和硝态氮储量、土壤容重显著增加(P<0.05)。土壤氨化速率和氮矿化速率在比对组间无显著差异(P>0.05),但硝化速率在重复砍伐后显著增加(P<0.05)。本研究表明,土壤养分库和氮转化对森林重复砍伐的响应方式不同。森林重复砍伐后,土壤有机碳库和氮库含量降低,磷库和无机氮库含量增加,氮素矿化和氨化速率变化不显著,硝化速率显著提高。更多还原

【Abstract】 Revealing the effects of forest clear-felling frequencies on soil nutrient pools and nitrogen transformation is important for understanding the response of nutrient cycling to clear-felling. In this study,three pairs of control and clear-felling( at different frequencies) communities were selected in evergreen broad-leaved forests in Tiantong,Zhejiang Province,to study the influence of clear felling on soil organic carbon,nitrogen and phosphorus pools,as well as soil nitrogen mineralization and nitrification. The results showed that repeated clear felling significantly lowered the stocks of soil total nitrogen and organic carbon( P < 0. 05),while significantly increased soil phosphorus,ammonium and nitrate contents,and soil bulk density( P < 0. 05). Repeated clear felling did not cause significant changes in soil nitrogen mineralization and ammonification rates( P > 0. 05),but significantly increased the soil nitrogen nitrification rate( P < 0. 05).更多还原