不同放牧强度对高寒草甸有毒植物多样性的影响

Effects of different grazing intensities on the diversity of poisonous plants inalpine meadow

摘要:

通过研究祁连山东段高寒草甸不同放牧强度下有毒植物丰富度、Shannon-Wiener指数、Pielou均匀度指数变化,结果表明:轻度放牧区有毒植物3个生物多样性指数均较高,丰富度和Shannon-Wiener指数都显著性高于其他3个放牧区,但Peilou指数与中度放牧区差异不显著(P＞0.05);同时轻度放牧区内有毒植物月份间变幅较大且差异显著(P＜0.05)。过度放牧区有毒植物的3个多样性指数在6,7和8月都显著性高于中度和重度放牧区(P＜0.05),但在10月显著低于其他3个放牧强度下有毒植物的生物多样性(P＜0.05);同时过度放牧区内有毒植物丰富度月份间变幅最大且差异显著(P＜0.05)。中度和重度有毒植物生物多样性指数较低,在6~8月,中度放牧区有毒植物的丰富度和Shannon-Wiener指数低于其他3个放牧区,但Peilou指数较高;同时中度和重度放牧区生物多样性指数月份间变幅较小。

Abstract:

The richness index,Shannon-Wiener index and Pielou evenness index of poisonous plants in alpine meadow under different grazing intensities were studied the in the eastern Qilian Mountains.The results showed that 3 biodiversity indices of poisonous plants in lightly-grazing group were high,and the richness index and Shannon-Wiener index were significantly higher than other 3 grazing groups (P＜0.05),but there was no significant difference in Peilou index between lightly-grazing group and moderately-grazing group (P＞0.05).The monthly variation of biodiversity indices of poisonous plants in lightly-grazing group was large and significant.(P＜0.05).The three diversity indices of poisonous plants in overgrazing group were significantly higher than moderately-grazing and heavily-grazing groups in June,July and August (P＜0.05),but significantly lower in October (P＜0.05) than other 3 grazing groups.The richness index of poisonous plants in overgrazing group had the greatest variation among months and the difference was significant (P＜0.05).The biodiversity index of poisonous plants in moderately and heavily-grazing groups was lower.The richness and Shannon-Wiener indices of poisonous plants in moderately-grazing group were lower than other 3 grazing groups from June to August,but the Peilou index was higher.The biodiversity indices of moderate and severe grazing groups changed slightly among months.