菇木林目标树择伐林窗的形成对土壤养分含量的影响

Effects of selective cutting of forest trees on content of soil nutrient in mushroom-cultivated stand

【目的】以浙江省庆元县菇木林为研究对象,探讨菇木林目标树择伐后形成的人工林窗对土壤养分含量和土壤质量的影响。【方法】在对照林分和择伐后林窗内设置调查样地,分层采集0~60 cm土层土壤样品,对比分析土壤养分元素含量和土壤pH值的变化情况。【结果】1)与对照相比,择伐6 a后林窗0~20 cm土层,土壤有机碳、全氮、水解性氮、有效磷含量和C/N比分别增加了25.55%、13.68%、42.34%、15.32%和10.04%;而20~40、40~60 cm土层,土壤有机碳含量分别下降了43.50%和54.68%,全氮含量分别下降了37.31%和44.43%,水解性氮含量分别下降了23.49%和10.28%,有效磷含量分别下降了11.06%、34.47%,C/N比分别下降了9.05%、19.65%。林窗0~20、40~60 cm土层土壤pH值分别下降了2.79%和0.56%,20~40 cm土层土壤pH值增加了0.94%,但差异均不显著。2)与对照林相比,林窗0~20、20~40、40~60 cm土层,土壤速效钾含量分别下降了28.02%、35.08%和0.25%,土壤交换性钙含量分别增加了83.16%、35.78%和42.00%,土壤交换性镁含量分别下降了19.26%、20.71%和7.18%。3)运用主成分分析,对表征土壤肥力的土壤pH值、有机碳、全氮、速效氮、有效磷、速效钾、交换性钙和交换性镁进行评价,综合评价表明,菇木林择伐6 a后形成的林窗有利于土壤质量的提升。【结论】研究结果为菇木林择伐经营的科学性和合理性提供了一定的理论依据,也为中国重要农业文化遗产——浙江省庆元香菇文化系统提供技术支撑。

【Objective】In order to reveal the effects of selective cutting of forest trees on the content of soil nutrient and soil quality in mushroom-cultivated stand in Qingyuan county,Zhejiang province.【Method】Survey plots of mushroom-cultivated and contrast(CK)stand were established,soil samples of 0-20 cm,20-40 cm,40-60 cm layers were collected and analyzed.【Result】1)compared with CK,the content in 0-20 cm soil layer of soil organic carbon(SOC),total N,available N,available P and C:N were increased by 25.55%,13.68%,42.34%,15.32%and 10.04%respectively.while in 20-40 cm and 40-60 cm soil layers,the content of SOC were decreased by 43.50%and 54.68%respectively,the contents of total N were decreased by 37.31%and 44.43%respectively,the contents of available N were decreased by 23.49%and 10.28%respectively,the contents of available P were decreased by 11.06%and 34.47%respectively;C:N were decreased by 9.05%and 19.65%respectively.The pH value were decreased by 2.79%,0.56%in 0-20 cm and 40-60 cm soil layers,while was increased by 0.94%in 20-40 cm soil layer without significant difference;2)compared with CK,the contents in 0-20 cm,20-40 cm,40-60 cm soil layers of available K were decreased by 28.02%,35.08%,0.25%respectively,exchangeable Ca were increased by 83.16%,35.78%,42.00%respectively and exchangeable Mg were decreased by 19.26%,20.71%and 7.18%respectively.3)Based on the method of the principal component analysis and evaluation of soil pH value,SOC,total N,available N,available P,available K,exchangeable Ca and exchangeable Mg,the soil quality of mushroom-cultivated stand was improved in 6 years later.【Conclusion】The results provided a certain theoretical basis for scientific management of mushroom-cultivated stand and technique support for Qingyuan Mushroom culture system of China’s important agricultural-cultural heritage.