三峡库区坡耕地典型香榧套种模式土壤碳氮磷及其生态化学计量特征  

Soil Carbon,Nitrogen and Phosphorus Stoichiometric Characteristics of Typical Torreya grandis Intercropping Systems on Sloping Farmland in the Three Gorges Reservoir Area

作　　者：陈胜伦 李天阳[1] 何丙辉[1] 刘玉民[1] 刘亚敏[1] 唐荣栋 唐林 CHEN Shenglun;LI Tianyang;HE Binghui;LIU Yumin;LIU Yamin;TANG Rongdong;TANG Lin(College of Resources and Environment,Southwest University,Chongqing 400716;Yunyang County Forest Resources Monitoring Center,Chongqing 404599;Yunyang County Zhongmiao Forestry Co.,Ltd.,Chongqing 404599)

机构地区：[1]西南大学资源环境学院,重庆400716 [2]云阳县森林资源监测中心,重庆404599 [3]云阳县中苗林业有限责任公司,重庆404599

出　　处：《水土保持学报》2023年第1期220-226,共7页Journal of Soil and Water Conservation

基　　金：重庆市科技兴林项目(2019-12);国家自然科学基金项目(U21A20187);中央高校基本科研业务费项目(SWU-KT22060)。

摘　　要：为阐明三峡库区坡耕地典型香榧套种模式对土壤碳(C)、氮(N)、磷(P)含量及其生态化学计量特征的影响,在重庆市云阳县宝坪镇香榧种植基地内,选取香榧纯林(TG)、香榧-黄精(TGP)、香榧-大豆(TGG)3种套种模式为研究对象,分析不同模式及土层深度下土壤C、N、P含量及其生态化学计量特征。结果表明:不同模式的土壤C含量无显著差异,N、P含量均表现为TGG(0.80,0.53 g/kg)>TGP(0.71,0.40 g/kg)>TG(0.56,0.39 g/kg),且与TG相比,TGG的N、P含量分别显著提高42.9%,35.9%。土壤C、N主要富集在0—10 cm土层,而P主要集中在10—20 cm土层。3种模式的土壤C∶N、C∶P、N∶P分别为8.39~10.73,31.63~45.22,3.25~5.61,均低于全国平均值(14.4,136.0,9.3)。N∶P<10,表明N为研究区限制性养分。相关性分析结果表明,土壤pH、容重和总孔隙度也是影响土壤C、N、P含量及其生态化学计量的重要指标。香榧套种模式有利于土壤养分的积累,TGG的C、N、P含量高于TGP和TG,有较好的培肥效果。To explore the effects of typical Torreya grandis intercropping systems on soil carbon(C),nitrogen(N),and phosphorus(P)content and their stoichiometric characteristics on sloping farmland in the Three Gorges Reservoir Area,three typical intercropping systems,T.grandis(TG),T.grandis-Polygonatum sibiricum(TGP),and T.grandis-Glycine max(TGG),were selected in the T.grandis planting bases located in Baoping Town,Yunyang County,Chongqing.The contents of C,N,P in soil and their ecological stoichiometric characteristics under different models and soil depths were analyzed.The results showed that there was no significant difference in soil C content among different systems.Both N and P contents followed the order of TGG(0.80,0.53 g/kg)>TGP(0.71,0.40 g/kg)>TG(0.56,0.39 g/kg),and compared with TG,N and P contents of TGG were significantly higher by 42.9%and 35.9%,respectively.Soil C and N mainly concentrated in the 0-10 cm soil layer,while P mainly concentrated in the 10-20 cm soil layer.Soil C∶N,C∶P and N∶P under the three systems was 8.39~10.73,31.63~45.22 and 3.25~5.61,respectively,which were all lower than the national average values(14.4,136.0,9.3).And the N∶P ratio was less than 10,indicating that N was the limiting nutrient in the study area.The results of the correlation analysis showed that soil pH,bulk density and total porosity were also important indicators affecting soil C,N,and P contents and their ecological stoichiometry.T.grandis intercropping systems significantly enhanced the accumulation of soil nutrients.The content of C,N and P of TGG was higher than that of TGP and TG,and TGG showed better fertilizer cultivation effect.

关 键 词：土壤养分 农林复合系统 土壤深度 三元相图 

分 类 号：S158.3[农业科学—土壤学]