近40年东北地区陆栖脊椎动物种群数量及其生境变化评估

Assessment of the changes in the number of terrestrial vertebrates and habitat in Northeast China over the last 40 years

生物多样性是生态平衡维持和生态过程与功能实现的基础,东北地区是我国乃至全球生物多样性最为丰富的地区之一。为研究和探讨东北地区陆栖脊椎动物种群数量与生境变化之间的关系,利用物种调查数据和生境遥感观测数据,以地球生命力指数、生态系统面积和破碎度等指示性指标,综合评估了近40年东北地区陆栖脊椎动物种群数量及其生境变化。结果表明:1970—2010年,东北地区陆栖脊椎动物种群数量下降了近70.1%,森林脊椎动物种群数量减少了近80.9%,草原和荒漠生态系统脊椎动物种群数量增加了近180.9%。1980—2010年,湿地物种种群数量减少了近75.7%。1980—2015年期间,农业和城镇建设用地增幅分别达到25.2%和32.3%,不断挤占和蚕食着自然生态空间,致使自然生境面积不断减少,减幅约为8.0%。自然生境景观破碎化程度总体呈现加重趋势,尤其是森林生境,破碎化指数增加约42.7%。但是,2005年之后,自然生境景观破碎化程度加重趋势趋缓,与2005年之后脊椎动物种群数量减少幅度减缓趋势一致。森林砍伐、人口增长、城镇化、交通建设等造成的自然生态系统破碎度增加和栖息地质量下降对大型兽类影响比较显著。

Biodiversity is the basis for maintaining ecological balance and realizing ecological process and function. Northeast China is one of the most biodiverse areas in China and even the whole world. To understand the changes of the number and habitats changes of terrestrial vertebrates in the Northeast China, we combined long time-series species survey data and habitat remote sensing data, selected living planet index （LPI）, area and fragmentation index of ecosystem types in different years as indicators, assessed the variation trend of terrestrial vertebrates and habitats in Northeast China in recent 40 years. The study showed the number of terrestrial vertebrate reduced by 70.1% from 1970 to 2010 in this area. The number of forest species reduced by 80.9% and the number of grassland and desert species increased by 180.9% from 1970 to 2010. The number of wetland species reduced by 75.7% from 1980 to 2010. The area of farmland and urban development increased by 25.2% and 32.3% from 1980 to 2015, respectively. With the continuous erode of natural ecological space such as reclamation of agriculture and urbanization, about 6.1% of the natural habitats were converted to artificial habitats. As a result, the natural habitats continued to decrease with a total decrease of about 8.0% in the area. The landscape fragmentation index of the natural habitat overall showed an increasing trend during 1980-2015. In particular, the index of fragmentation of forest habitats increased by about 42.7%, but the rising trend was lower after 2005, which was consistent with the decreasing trend in the number of vertebrate populations after 2005. This study showed that the number of large mammals in Northeast China has decreased sharply in the past 40 years, and the main reasons for this change are the increase in fragmentation of natural ecosystems and the decline of habitat quality caused by deforestation, population growth, urbanization, and traffic construction.