The interaction between poisonous plants and soil quality in response to grassland degradation in the alpine region of the Qinghai-Tibetan Plateau

The objective of this study was to explore the distribution of poisonous plants and soil quality in relation to grassland degradation in the Qinghai-Tibetan Plateau (QTP) by employing poisonous plants characteristics including diversity index, coverage and composition and the soil properties including soil physical, chemical, and biological indicators. The degraded grasslands (DGs) had significantly increased cover and diversity values of poisonous plants compared with the non-DGs (NDGs). Grassland use types had significant effects on the composition and characteristics of poisonous plants. The NDGs had increased levels of soil nutrients and soil enzyme activities, with decreased soil pH and bulk density (BD), indicating a higher and better soil nutrient status compared with DGs. The soil texture, soil pH, and soil BD were very important in affecting the structures of poisonous plants. We concluded that grassland degradation had significant effect on poisonous plants coverage and diversity; conversely, poisonous plants also aggregated the grassland degradation, decreasing the soil fertility in the QTP.