晋西北黄土丘陵退耕还草区优势种功能性状对群落生产力的影响  

Effects of functional characters of dominant species on community productivity in grain-for-grasslands of Loess Hilly region of northwest Shanxi province

作　　者：唐学娟 赵峰侠 张瑞 闫丽飞 冀雯霞 TANG Xuejuan;ZHAO Fengxia;ZHANG Rui;YAN Lifei;JI Wenxia(College of Geography Science,Shanxi Normal University,Linfen 041000,Shanxi)

机构地区：[1]山西师范大学地理科学学院,临汾041000

出　　处：《干旱区资源与环境》2020年第9期164-170,共7页Journal of Arid Land Resources and Environment

基　　金：山西省面上青年基金项目(201901D211387);山西省面上青年基金项目(201801D221336);国家自然科学基金(41807518);山西师范大学校级自然科学基金项目(02080163)资助。

摘　　要：晋西北黄土丘陵区是我国水土流失最严重的区域之一。因此,提升群落生产力对当地生态环境改善至关重要,但目前甚少从优势种功能性状角度探讨群落生产力变化的机制。本文探究晋西北黄土丘陵退耕还草区植被优势种9种功能性状的群落权重均值(community-weighted means,CWM)之间的相关性及其对群落生产力的影响。结果显示:优势种相对分枝数CWM与株高、叶片含碳量、叶片碳氮比、叶面积、叶片含氮量、叶干物质含量的CWM呈极显著相关性(P<0.01)。优势种的5种功能性状CWM值即相对分枝数(R^2=0.097,P<0.01)、株高(R^2=0.097,P<0.01)、叶片碳含量(R^2=0.040,P<0.05)、叶片碳氮比(R^2=0.031,P<0.05)和叶面积(R^2=0.029,P<0.05)对群落生产力具有影响,且通过逐步回归分析发现优势种的相对分枝数CWM和株高CWM是影响群落生产力的主要功能性状(R^2=0.130,P<0.01)。以上结果表明晋西北黄土丘陵退耕还草区优势种功能性状是影响群落生产力变化的主要机制之一。因此,在黄土丘陵退耕还草区中,应加强对优势种的管理,尤其是相对分枝数较少而株高较大的优势种。The Loess Hilly area in northwestern Shanxi province is one of the most serious soil erosion areas in China, so improving the community productivity is very important to improve the local ecological environment. But at present, there is little discussion on the mechanism of community productivity change from the perspective of dominant species functional properties. In this paper, the relationship between community weighted means(CWM) of nine functional characters of dominant species in grain-for-grasslands of Loess Hilly region of northwestern Shanxi province and its influence on community productivity were studied. The results showed the relative branch number CWM of dominant species was significantly correlated with plant height CWM, leaf carbon content CWM, leaf carbon nitrogen ratio CWM, leaf area CWM, leaf nitrogen content CWM and leaf dry matter content CWM(P<0.01). The CWM values of five functional characters of dominant species: relative branch number CWM(R^2=0.097, P<0.01), plant height CWM(R^2=0.097, P<0.01), leaf carbon content CWM(R^2=0.040, P<0.05), leaf carbon nitrogen ratio CWM(R^2=0.031, P<0.05) and leaf area CWM(R^2=0.029, P<0.05) influence on community productivity, and the relative branch number CWM and plant height CWM of dominant species are the main functional characters that affect the community productivity(R^2=0.130, P<0.01) through stepwise regression analysis. The above results show that the functional characteristics of dominant species in grain-for-grasslands of Loess Hilly region of northwestern Shanxi province is one of the main mechanisms affecting the change of community productivity. Therefore, in grain-for-grasslands of Loess Hilly region of northwestern Shanxi province, the management of dominant species should be strengthened, especially the dominant species with less relative branches and larger plant height.

关 键 词：黄土丘陵区 退耕还草 优势种功能性状 生产力 质量比例假说 

分 类 号：S812[农业科学—草业科学]