利用方式对大针茅草原群落功能多样性的影响

Effect of Utilization on Community Functional Diversityin Stipagrandis Steppe

大针茅(Stipagrandis)草原是内蒙古典型草原重要组成部分,对畜牧业的发展和生态环境有重要意义。本文通过野外取样,结合室内分析,对不同草地利用方式下大针茅草原群落功能性状进行了研究,分析了群落植株高度(CWM_H)、叶片长度(CWM_(LL))、叶面积(CWM_(LA))、叶片碳含量(CWM_(LCC))、叶片氮含量(CWM_(LCC))及叶片碳氮比(CWMC/N)6个功能性状指标在不同利用方式下的差异及其相关性,旨在探讨大针茅草原群落功能性状对利用方式的响应。结果表明:与对照(CK)相比,放牧(G)与刈割(M)显著增加了群落叶片长度(CWM_(LL))及叶片氮含量(CWMLNC)(p<0.05),显著降低了群落叶片碳含量(CWM_(LCC))及叶片碳氮比(CWMC/N)(p<0.05);放牧(G)显著降低了群落植株高度(CWM_H)、叶片面积(CWM_(LA))(p<0.05);刈割(M)显著增加了群落叶片面积(CWM_(LA))(p<0.05)。并且,放牧(G)与围封(CK)均表现出植株高度(CWM_H)与叶片长度(CWM_(LL))呈显著或极显著的正相关关系,而刈割使二者关系不显著,使植株高度(CWM_H)与叶片面积(CWM_(LA))二者关系显著;刈割(M)使得叶片碳含量(CWM_(LCC))与叶片氮含量(CWM_(LCC))呈极显著的负相关关系。

Stipagrandis grassland is an important part of the typical grassland in Inner Mongolia. It has great significance for the development of animal husbandry and its ecological environment In this paper, field experiments were conducted to study community functional diversity inStipa grandis steppe grasslands under different grassland utilization ways. The effects of communityheight （CWMH） , leaflength （CWMLL）, leaf area （CWMLA） , leaf carbon content（CWMLCC）, leaf nitrogen content （CWMLNC） and carbon nitrogen ratio （CWMC/N）in different ways of utilization were studied in order to explore the response of community functional traits to the utilization patterns. Results show that compared with the enclosure（CK）, grazing（G） and mowing（M） significantly in creased leaf length （CWMLL） and leaf nitrogen content （CWMLNc） （p〈0.05）, having significantly reducd leaf carbon content（CWMLcc） and carbon nitrogen ratio（CWMc/N） （p〈0. 05）. Grazing（G） significantly reduced corn munity plant height（CWMH） and leaf area （CWMLA） （p〈0. 05）. Mowing（M） significantly increased community leaf area （CWMLA） （p〈0.05）. Grazing（G）and enclosure （CK） shownthat plant height（CWMH） and leaf length （CWMLL） were significantly or extremely significantly positive correlation, while no significant relationship be tween plant height（CWMH） and leaf length（CWMLL） by mowing, but mowing （M） results in a extremely signifi candy negative correlation between leaf carbon content（CWMLcc） and leaf nitrogen content （CWMLcc）.