土地复垦的覆土厚度及覆土基质确定

1研究方法 1．1研究区概况研究区位于河南省巩义市大峪沟煤矿,属黄土丘陵地区,为较典型的半干旱气候类型。土地复垦的主要内容为塌陷区土地复垦和矸石山复垦。 1．2调查方法该研究的重点放在不同生活型植物物种与地境层片的对应关系,以及各层片的水肥条件与植物长势的关联这两个问题上。地面以上开展植被调查,地面以下开展地境结构及地境内生态因子调查：     

Islands in the ice stream: were spawning habitats for native salmonids in the Great Lakes created by paleo‐ice streams?

Lake trout Salvelinus namaycush, lake whitefish Coregonus clupeaformis and cisco Coregonus artedi are salmonid fishes native to the Laurentian Great Lakes that spawn on rocky substrates in the fall and early winter. After comparing the locations of spawning habitat for these species in the main basin of Lake Huron with surficial substrates and the hypothesized locations of fast‐flowing Late Wisconsinan paleo‐ice streams, we hypothesize that much of the spawning habitat for these species in Lake Huron is the result of deposition and erosion by paleo‐ice streams. This hypothesis may represent a new framework for the identification and protection of spawning habitat for these native species, some of which are currently rare or extirpated in some of the Great Lakes. We further suggest that paleo‐ice streams may have been responsible for the creation of native salmonid spawning habitat elsewhere in the Great Lakes and in other glaciated landscapes.     

长白山自然保护区水獭种群数量变动与资源保护

1980-2010年,对长白山自然保护区3条主要河流的水獭种群数量和栖息地食物资源进行了长期监测;2006-2008年冬季采用路线直接计数法对18条河流进行野外定点调查;2004-2010年5-8月对头道白河流域的水獭活动情况进行了定点全天观察;2006-2008年冬季对水獭栖息地8条河流的无冰水面进行了调查。结果表明...     

Patterns in young‐of‐year smallmouth bass microhabitat use in multiple stream segments with contrasting land uses

Abstract Young‐of‐the‐year (YOY) smallmouth bass, Micropterus dolomieu Lacepéde, were evaluated in streams from eight catchments with two contrasting land uses to determine their use of microhabitats under a variety of stream conditions. Step‐wise discriminant function analyses revealed patterns of habitat use by discriminating used from available microhabitat conditions. Velocity was significant in 88% of streams sampled, whereas depth was significant in only the smallest stream in the forest‐dominated catchments and 75% of stream segments located in pasture‐dominated catchments. Mean velocities used by YOY bass were lower than available velocities, and mean depths used were greater than mean availability in all cases. Substrata varied significantly with availability in different stream segments. Error rates associated with classification ranged from 5 to 39%. Results indicate that YOY smallmouth bass are somewhat opportunistic, but use low‐velocity habitats in most cases and deeper water when streams are impacted by pasture land use and associated physical changes.     

Predictors of Chinook salmon extirpation in California’s Central Valley

Abstract Chinook salmon, Oncorhynchus tshawytscha (Walbaum), populations have declined rapidly along the western coast of North America since the year 2000, possibly because of factors such as habitat loss, altered hydrology and barriers to migration. However, few analyses have rigorously examined which of these factors actually explain historical patterns of extirpation. Data were compiled on flow regimes, habitat loss and migration barriers for 27 streams that historically supported autumn run salmon and 22 streams that supported spring runs. The probability of extirpation in streams supporting autumn run was predicted solely by migration barriers. All other factors were >10⁵ times less likely to explain existing variation. By contrast, models for spring run salmon suggest that habitat loss and altered flow regimes were also predictors of extirpation. These results suggest that regional extirpation of Chinook salmon has been driven by multiple forms of environmental change, and restoration efforts must address a multitude of bottlenecks that now impact spring and autumn run populations.     

物理栖息地模型在中华鲟自然繁殖生态流量决策中的应用

以国家一级保护物种中华鲟（Acipenser sinensis）为研究对象,探讨三峡大坝和葛洲坝水利工程在不同流量调度措施下对中华鲟产卵栖息地的影响。通过考虑中华鲟生境需求特性建立了中华鲟产卵场的物理栖息地模型,根据模型得出的适宜栖息地面积变化来量化不同的流量调度措施对其产卵场质量的影响,然后利用实测的中华鲟产卵量和资源量数据来验证和评价物理栖息地模型的可靠性和实用性,从而进行合理的生态流量决策。结果发现,年平均适宜栖息地面积的变化曲线与中华鲟的产卵量和资源量变化曲线有着相同的变化趋势,从而推断适宜栖息地     

Site‐fidelity and movement patterns of bottlenose dolphins (Tursiops truncatus) in central Argentina: essential information for effective conservation

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