坡向对新疆天山北坡山地草原植被 多样性的影响

【目的】 研究草地植被多样性对坡向的响应规律,并分析其月动态变化规律。【方法】 以新疆天山北坡山地草原为研究对象,采用野外调查取样的方法,测定不同坡向(东坡、坡顶和西坡)、不同月份(6~9月)的草地植被多样性指数。【结果】 (1)坡向对Patrick丰富度指数、Simpson优势度指数、Shannon-Wiener多样性指数的影响较小(P>0.05),而6月和9月西坡比东坡的Pielou均匀度指数分别显著增加了7.4%和10.9%(P<0.05)(2)不同坡向的Patrick丰富度指数以及坡顶和西坡的Simpson优势度指数、Shannon-Wiener指数在6和8月均高于7和9月,且基本呈先降后升再降的变化趋势,而Pielou均匀度指数对月份的响应不明显。【结论】 植被多样性对坡向(东坡、坡顶、西坡)的响应较小,但其月动态变化显著。

Effects of Slope Aspect on the Vegetation Diversity of Mountain Steppe in the Northern Slope of Tianshan Mountain,Xinjiang

【Objective】 To study the effect of slope aspect on the vegetation diversity of mountain steppe, and reveal the change rule of vegetation diversity in different growing seasons.【Method】 The mountain steppe in the northern slope of Tianshan Mountain was taken as the research object, and the method of field investigation and sampling were used, and grassland vegetation diversity in the different slope (east and west slope, slope crest) and different growth periods (6-9 months) were measured.【Result】 (1) The influence of slope aspect on Patrick richness index, Simpson dominance index, Shannon-wiener diversity index were relatively small (P>0.05), but Pielou evenness index on west slope in June and September were increased by 7.4% and 10.9% compared with that in east slope (P<0.05). (2) The Patrick richness index in different slope aspects and the Simpson dominance index, Shannon-wiener diversity index on the slope crest and west slope in June and August were higher than those in July and September.【Conclusion】 The response of vegetation diversity to slopes (west slope, east slope and slope crest) is small, but monthly dynamic changes of vegetation diversity are significant.