浙南山区农田生态系统入侵杂草种类组成及海拔分布特征分析OA

Based on the field investigation of farmland ecosystem in Songyang County,Zhejiang Province,the species composition,altitude distribution pattern and habitat preference of invasive weeds were studied.The results showed that a total of 10 species of invasive weeds were recorded,belonging to 7 families,with Compositae plants being the most represented family(4 species),accounting for 40.0%of the total species.The invasion intensity(average coverage)exhibited a declining trend with the increase of altitude.The average coverage in the low-altitude group(＜150 m)was 64.5%±22.0%(n=9),which was higher than that in the mid-altitude group(150-250 m,48.0%±15.2%,n=8)and that in the high-altitude group(＞250 m,34.7%±9.0%,n=3),with the Kruskal-Wallis test showing the marginal significance(H=5.95,P=0.051).The Chi-square test showed that the distribution of species was significantly correlated with altitude(χ2=34.49,P=0.011).Ageratum conyzoides was exclusively distributed in the high-altitude areas,while Pontederia crassipes Mart.was concentrated in the mid-altitude areas.The results provided a reference for monitoring,early warning and classified prevention and control of invasive weeds in the mountainous regions of southern Zhejiang.