The Nature Conservancy, 101 East Grand River Avenue, Lansing, MI 48906-4374, USA.
Conserv Biol. 2010 Aug;24(4):1002-11. doi: 10.1111/j.1523-1739.2010.01460.x. Epub 2010 Mar 11.
Protected areas are a cornerstone of conservation and have been designed largely around terrestrial features. Freshwater species and ecosystems are highly imperiled, but the effectiveness of existing protected areas in representing freshwater features is poorly known. Using the inland waters of Michigan as a test case, we quantified the coverage of four key freshwater features (wetlands, riparian zones, groundwater recharge, rare species) within conservation lands and compared these with representation of terrestrial features. Wetlands were included within protected areas more often than expected by chance, but riparian zones were underrepresented across all (GAP 1-3) protected lands, particularly for headwater streams and large rivers. Nevertheless, within strictly protected lands (GAP 1-2), riparian zones were highly represented because of the contribution of the national Wild and Scenic Rivers Program. Representation of areas of groundwater recharge was generally proportional to area of the reserve network within watersheds, although a recharge hotspot associated with some of Michigan's most valued rivers is almost entirely unprotected. Species representation in protected areas differed significantly among obligate aquatic, wetland, and terrestrial species, with representation generally highest for terrestrial species and lowest for aquatic species. Our results illustrate the need to further evaluate and address the representation of freshwater features within protected areas and the value of broadening gap analysis and other protected-areas assessments to include key ecosystem processes that are requisite to long-term conservation of species and ecosystems. We conclude that terrestrially oriented protected-area networks provide a weak safety net for aquatic features, which means complementary planning and management for both freshwater and terrestrial conservation targets is needed.
保护区是保护的基石，主要围绕陆地特征设计。淡水物种和生态系统面临高度威胁，但现有保护区对淡水特征的代表性知之甚少。以密歇根州的内陆水域为例，我们量化了保护地内四种关键淡水特征（湿地、河岸带、地下水补给、稀有物种）的覆盖情况，并将其与陆地特征的代表性进行了比较。湿地被纳入保护区的频率高于随机预期，但河岸带在所有（GAP1-3）保护区中都被低估了，特别是在源头溪流和大河中。然而，在严格保护区（GAP1-2）内，由于国家野生和风景河流计划的贡献，河岸带的代表性很高。地下水补给区的代表性与流域内保护区网络的面积基本成正比，尽管与密歇根州一些最有价值的河流相关的补给热点几乎完全没有得到保护。保护区内物种的代表性在专性水生、湿地和陆地物种之间存在显著差异，陆地物种的代表性一般最高，而水生物种的代表性最低。我们的结果表明，需要进一步评估和解决保护区内淡水特征的代表性问题，并扩大差距分析和其他保护区评估，以纳入关键的生态系统过程，这是物种和生态系统长期保护所必需的。我们的结论是，以陆地为导向的保护区网络为水生特征提供了一个薄弱的安全网，这意味着需要为淡水和陆地保护目标制定补充的规划和管理。
