晋西北丘陵风沙区人工针叶林枯落物–土壤碳氮磷对放牧干扰的响应  

Response of litter-soil C,N,and P to grazing disturbance in coniferous plantations in sandy-hilly region of Northwest Shanxi Province,China

作　　者：陕莎莎 张鸾[1] 赵利华 李素清[1] SHAN Shasha;ZHANG Luan;ZHAO Lihua;LI Suqing(Institute of Loess Plateau,Shanxi University,Taiyuan 030006,China;School of Energy and Power Engineering,North University of China,Taiyuan 030051,China)

机构地区：[1]山西大学黄土高原研究所,太原030006 [2]中北大学能源与动力工程学院,太原030051

出　　处：《应用与环境生物学报》2024年第2期229-237,共9页Chinese Journal of Applied and Environmental Biology

基　　金：黄河流域生态保护和高质量发展联合研究项目(2022-YRUC-01-0103);国家自然科学基金青年基金项目(41301609);山西省面上自然基金项目(201901D111040);山西大学研究生教育创新项目;太原市市容环境卫生科学研究所研发项目(02050120120130)资助。

摘　　要：为探究晋西北丘陵风沙区人工针叶林林下枯落物–土壤养分特征及其对林间放牧的响应,以恢复年限约30年的油松和樟子松人工林为研究对象,对比其在有/无放牧干扰下枯落物(未分解层和半分解层)–土壤(0-20 cm)C、N、P含量、化学计量比、酶活性和土壤微生物生物量差异.结果表明:4个样地枯落物有机C、全N和全P含量分别为338.98-545.95、6.63-11.59和1.51-2.19 g/kg,C:N、C:P和N:P分别为31.80-78.93、161.29-361.84和3.45-6.58,蔗糖酶、脲酶和磷酸酶活性分别为26.08-34.52、0.03-0.29和0.29-0.97 mg g-1h-1.土壤有机C、全N和全P含量变化范围分别为4.65-9.54、0.78-1.29和0.24-0.47 g/kg,硝态氮、铵态氮、速效磷和微生物生物量C、N含量分别为0.21-0.28、10.90-15.38、1.94-4.00和28.17-83.55、5.16-10.18 mg/kg,C:N、C:P和N:P分别为6.00-7.40、18.68-24.23和2.77-3.62,蔗糖酶、脲酶和磷酸酶活性分别介于17.90-24.70、1.08-1.71、0.46-1.01 mg g^(-1)h^(-1).放牧干扰使油松和樟子松林枯落物半分解层脲酶和磷酸酶活性,土壤有机C、全N、全P、微生物生物量C含量及磷酸酶活性均显著增加,还使油松林枯落物未分解层全N、N:P及土壤脲酶活性,樟子松林枯落物两层全P含量、未分解层脲酶活性和半分解层蔗糖酶活性及土壤硝态氮、速效磷和蔗糖酶活性显著增加,且樟子松林土壤有机C、全N、全P含量,尤其是微生物生物量C、硝态氮和速效磷,以及与C、N、P有关的土壤蔗糖酶、脲酶和磷酸酶活性均显著高于油松林.因此,研究区枯落物–土壤养分循环主要受到N和P的共同限制,林间适度放牧可以缓解人工林枯落物-土壤N、P限制,加速枯落物分解和土壤C、N、P尤其是有效态转化,樟子松更利于增加土壤C、N、P的有效性,可以考虑在区域造林规划和小老树更新改造时适当增加樟子松人工林的比例.(图4表3参42)This study investigated the nutritional characteristics of litter-soil and their response to understory grazing in coniferous plantations within the sandy-hilly region of Northwest Shanxi,focusing on Pinus tabulaeformis and P.sylvestris var.mongolica plantations with a restoration period of approximately 30 years.We conducted a comparative analysis,examining differences in the levels of carbon,nitrogen,and phosphorus,C:N,C:P,and N:P stoichiometry ratios,enzyme activities,and soil microbial biomass between two types of plantation litter(undecomposed and semi-decomposed layers)–soil(0–20 cm)with or without grazing disturbance.The results showed that the levels of organic carbon,total nitrogen,and total phosphorus in the litter from the four sites were in the range of 338.98–545.95,6.63–11.59,and 1.51–2.19 g/kg,respectively.Their C:N,C:P,and N:P ratios were 31.80–78.93,161.29–361.84,and 3.45–6.58,respectively,and the activities of sucrase,urease,and phosphatase were 26.08–34.52,0.03–0.29,and 0.29–0.97 mg g^(-1)h^(-1),respectively.In addition,the levels of soil organic carbon,total nitrogen,and total phosphorus from the four sites were in the range of 4.65–9.54,0.78–1.29,and 0.24–0.47 g/kg,respectively,and the levels of soil nitrate nitrogen,ammonium nitrogen,available phosphorus and microbial biomass C and N were 0.21–0.28,10.90–15.38,1.94–4.00,28.17–83.55,and 5.16–10.18 mg/kg,respectively.The C:N,C:P,and N:P ratios were 6.00–7.40,18.68–24.23,and 2.77–3.62,respectively and the activities of soil sucrase,urease,and phosphatase were 17.90–24.70,1.08–1.71,and 0.46–1.01 mg g^(-1) h^(-1),respectively.Grazing disturbance significantly increased the activities of urease and phosphatase in the semi-decomposed litter layer as well as soil organic carbon,total nitrogen,total phosphorus,microbial biomass C,and the activity of phosphatase in P.tabulaeformis and P.sylvestris var.mongolica plantations.In addition,grazing disturbance significantly increased the total nitrogen conte

关 键 词：晋西北丘陵风沙区 人工针叶林 枯落物 土壤 化学计量 放牧 

分 类 号：S15[农业科学—土壤学]