Multiple and combined threats from habitat degradation, DAMS, water withdrawals, pollution, and overexploitation have led to the decline of many catfish populations.

栖息地环境恶化、水坝、水位下降、污染和过度捕捞等等多种组合威胁，已经导致了许多种鲶鱼的数量下降。

We know what is causing the decline in Numbers of wild tigers: illegal poaching; illegal wildlife trade; loss of habitat through conversion, encroachment, and land degradation.

我们知道是什么原因导致了野生老虎数量的下降，这些原因就是：非法偷猎；非法野生动植物贸易；变更用途、侵占和土地退化导致的栖息地丧失。

Species are being threatened by habitat loss and degradation, invasive species, climate change, over-exploitation, pollution and wildlife disease.

由于栖息地的丧失或退化，外来物种、气候变化、过度采伐、环境污染以及野生物疾病的影响，各类物种正在受到威胁。

With the reason of the degradation of Wetlands waterfowl habitat, the Dongting Lake wetland waterfowl habitat conservation plans were put forward based on GAP analysis method in this paper.

针对湿地水禽生境退化的原因，本文基于GAP分析方法，提出了洞庭湖自然保护区的调整方案和湿地水禽生境的保护策略。

The greatest threat to the world's living creatures is the degradation and destruction of habitat, affecting 9 out of 10 threatened species.

生态环境的退化和破坏是对地球生灵的最大威胁，每十种面临威胁的物种，有九种受其影响。