Department of Forest and Wildlife Ecology, University of Wisconsin-Madison, Madison, WI 53706, USA.
Conserv Biol. 2012 Oct;26(5):821-9. doi: 10.1111/j.1523-1739.2012.01867.x. Epub 2012 Jun 25.
Changes in land use and land cover have affected and will continue to affect biological diversity worldwide. Yet, understanding the spatially extensive effects of land-cover change has been challenging because data that are consistent over space and time are lacking. We used the U.S. National Land Cover Dataset Land Cover Change Retrofit Product and North American Breeding Bird Survey data to examine land-cover change and its associations with diversity of birds with principally terrestrial life cycles (landbirds) in the conterminous United States. We used mixed-effects models and model selection to rank associations by ecoregion. Land cover in 3.22% of the area considered in our analyses changed from 1992 to 2001, and changes in species richness and abundance of birds were strongly associated with land-cover changes. Changes in species richness and abundance were primarily associated with changes in nondominant types of land cover, yet in many ecoregions different types of land cover were associated with species richness than were associated with abundance. Conversion of natural land cover to anthropogenic land cover was more strongly associated with changes in bird species richness and abundance than persistence of natural land cover in nearly all ecoregions and different covariates were most strongly associated with species richness than with abundance in 11 of 17 ecoregions. Loss of grassland and shrubland affected bird species richness and abundance in forested ecoregions. Loss of wetland was associated with bird abundance in forested ecoregions. Our findings highlight the value of understanding changes in nondominant land cover types and their association with bird diversity in the United States.
土地利用和土地覆盖的变化已经并将继续影响全球生物多样性。然而,由于缺乏空间和时间上一致的数据,了解土地覆盖变化的广泛空间影响一直具有挑战性。我们使用美国国家土地覆盖数据集土地覆盖变化改造产品和北美繁殖鸟类调查数据,研究了土地覆盖变化及其与主要具有陆地生活周期的鸟类(陆地鸟类)多样性的关系,这些鸟类分布于美国大陆。我们使用混合效应模型和模型选择按生态区对关联进行排名。在我们的分析中,有 3.22%的区域的土地覆盖从 1992 年到 2001 年发生了变化,鸟类物种丰富度和数量的变化与土地覆盖变化密切相关。物种丰富度和数量的变化主要与非主导类型的土地覆盖变化有关,但在许多生态区,与物种丰富度相关的土地覆盖类型与与数量相关的土地覆盖类型不同。在近所有生态区,与自然土地覆盖的持续存在相比,将自然土地覆盖转化为人为土地覆盖与鸟类物种丰富度和数量的变化更为密切相关,而在 17 个生态区中的 11 个,与数量相比,不同的协变量与物种丰富度更为密切相关。草原和灌木地的丧失影响了森林生态区的鸟类物种丰富度和数量。湿地的丧失与森林生态区鸟类的数量有关。我们的研究结果强调了了解非主导土地覆盖类型变化及其与美国鸟类多样性的关系的重要性。