杨树-冬小麦间作系统细根分布特征及对施氮的响应  

Distribution of Fine Roots in Poplar-Winter Wheat Intercropping System and Its Response to Nitrogen Fertilization

作　　者：吴永波[1,2] 吴殿鸣[1] 薛建辉[1,2] 褚军[1] 

机构地区：[1]南京林业大学南方现代林业协同创新中心,江苏南京210037 [2]南京林业大学江苏省林业生态工程重点实验室,江苏南京210037

出　　处：《生态与农村环境学报》2015年第3期320-325,共6页Journal of Ecology and Rural Environment

基　　金：国家林业局"948"项目(2013-4-63);国家林业公益性行业科研专项(200904001-3);江苏省生物学优势学科建设项目

摘　　要：以太湖流域杨树一冬小麦问作（简称杨麦问作）系统和冬小麦单作地为研究对象，研究了不同施氮量下杨麦问作系统中冬小麦和杨树细根的时空分布特征与冬小麦单作系统之间的差异，探讨林木根系在减少径流中养分流失方面的作用。结果表明：（1）单作冬小麦根长密度和单位土体根干质量均大于问作系统，问作系统中越靠近林带的冬小麦根长密度和单位土体根干质量越小。（2）单作地和问作系统冬小麦根长密度和单位土体根干质量最大值均出现在灌浆期。（3）随着施氮量的加大，冬小麦和杨树细根根长密度和单位土体根干质量均有所增加，且在问作系统中〉40～80cm土层杨树细根根长密度和根干质量所占比例增加。（4）问作系统减少了硝态氮随淋溶的流失量，灌浆期减少幅度为49．08％～55．49％。The method of stratified digging was adopted to study temporal and spatial distribution of fine roots in a four.year old poplar.winter wheat intercropping system relative to nitrogen fertilization and its difference from that in the winterwheat mono.cropping system, and to explore effect of the intercropping system reducing nutrient loss with runoff. Resultsshow that （1） the winter wheat in the mono.cropping system was higher than that in the intercropping system in terms offine root length density and root dry weight per unit of soil; （2） the peaks of root length density and root dry weight per u.nit of soil appeared during the wheat milking stage in both systems; （3） with increasing nitrogen application rate,both thewheat and the poplar increased in fine root length density and root dry weight per unit of soil and for poplar the increasemainly occurred in the 〉 40 - 80 cm soil layers; and （ 4） intercropping reduced nitrogen loss with leaching by49.. 08%-55.. 49%.

关 键 词：氮肥 细根 根长密度 根干质量 杨麦间作 太湖 

分 类 号：S718.59[农业科学—林学]