华北落叶松、兴安杨树人工林对土壤养分变化的影响

摘要

Plantation is a special biological community in artificial control,and affected greatly by human activity.Therefore,it faces many questions such as the wood soil degeneration and decreased forest productivity.The differences of the soil nutrient for plantations of the confier and broadleaf tree in the same site were investigated to discuss whether the plantation can lead to the soil degeneration or not.The soil organic matter,active organic matter,total nutrient and available nutrient content at different soil layer of 0 ≤H＜60 cm were studied in Larix principis-rupprechtii plantation and Populus hsinganica C.Wang et Skv.plantation in Yijiahe Pasture,Duolun County,Inner Mongolia in 2011.The results showed:in the same site (meadow chestnut soil),the contents of organic matter,active organic matter and total nitrogen at 0 ≤H＜60 cm soil layer of L.principis-rupprechtii forest were the highest,17.99,10.76 and 1.04 g · kg-1,respectively.The second ones in P.hsinganica forest land were 17.09,10.19 and 0.92 g · kg-1,respectively.The lowest ones in the control grassland were 11.26,9.15 and 0.74 g · kg-1,respectively.Moreover,the average contents of total phosphorus,available nitrogen,available phosphorus and available potassium at 0 ≤ H＜60 cm soil layer in P.hsinganica forest land were higher than those in L.principis-rupprechtii forest land and the control grassland.At 0≤H＜60 cm soil layer in the central position of interface layer of L.principis-rupprechtii and P.hsinganica forest,the average content of organic matter,active organic matter,total nitrogen and total phosphorus were 16.76,9.09,1.03 and 0.73 g · kg-1,lower than those in P.hsinganica forest land,respectively; And the average content of total potassium,available nitrogen,available phosphorus and available potassium in the central position of interface layer of L.principis-rupprechtii forest and P.hsinganica were 27.77 g ·kg-1,16.41 mg · kg-1,38.34 mg · kg-1 and 303.58 mg · kg-1,higher than those in P.hsinganica forest land,14.95 g ·kg-1,15.18 mg · kg-1,30.05 mg · kg-1 and 258.82 mg · kg-1,respectively.%人工林是在人为控制下形成的一个特殊的生物群落,极易受人为活动影响,造成林地土壤理化性质发生退化、林木生产力下降等诸多问题.因此,在相同立地条件下研究针叶树、阔叶树种人工造林对土壤养分影响的差异,对探讨人工造林是否能够导致土壤质量衰退等问题具有重要意义.2011年研究了内蒙古多伦县一家河牧场华北落叶松(Larix principis-rupprechtii Mayr)人工林和兴安杨(Populus hsinganica C.Wang et Sky.)人工林土层深(H)0≤H＜60 cm土壤有机质、活性有机质、土壤全量养分和速效养分质量分数的变化.结果表明:在相同立地(草甸栗钙土)条件下,兴安杨林地0≤H＜60 cm土壤有机质、活性有机质、全氮平均质量分数最高,分别为17.99、10.76、1.04g·kg-1；其次是华北落叶松林地,分别为17.09、10.19、0.92 g·kg-1；对照草地则最低,分别为11.26、9.15、0.74 g·kg-1.此外,兴安杨林地0≤H＜60 cm土壤全磷、速效氮、速效磷、速效钾平均质量分数也高于华北落叶松林地和对照草地.落叶松林和兴安杨林界面层0≤H＜60 cm土壤有机质、活性有机质、全氮、全磷平均质量分数分别为16.76、9.09、1.03、0.73 g·kg-1,均低于兴安杨林地的；落叶松林和兴安杨林界面层0≤H＜60 cm土壤全钾、速效氮、速效磷、速效钾平均质量分数分别为27.77 g· kg-1,16.41、38.34、303.58 mg·kg-1,均高于兴安杨林地的(分别为14.95 g· kg-1,15.18、30.05、258.82 mg· kg-1).