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31.
Island species are difficult to conserve because they face the synergy of climate change, invasive species, deforestation, and increasing human population densities in areas where land mass is shrinking. The Caribbean island of Hispaniola presents particular challenges because of geopolitical complexities that span 2 countries and hinder coordinated management of species across the island. We employed species distribution modeling to evaluate the impacts of climatic change and anthropogenic activities on the distribution of an endemic mammal of conservation concern, the Hispaniolan solenodon (Solenodon paradoxus). We aggregated occurrence points for this poorly known species for the Last Glacial Maximum (LGM) and the present (1975–2016) based on museum collections, online biodiversity databases, and new field surveys. We quantified degree of overlap between periods and scenarios with Schoener's D. Through a conservation paleobiology lens, we found that over time humans played an increasing role in shaping the distribution of S. paradoxus, thus, providing a foundation for developing conservation strategies on appropriate spatiotemporal scales. Human population density was the single most important predictor of S. paradoxus occurrence. Densities >166 people/km2 corresponded to a near-zero probability of occurrence. Models that accounted for climate but not anthropogenic variables falsely identified suitable habitat in Haiti, where on-the-ground surveys confirm habitat is unavailable. Climate-only models also significantly overestimated the potential for habitat connectivity between isolated populations. Our work highlights that alternative fates for S. paradoxus in the Anthropocene exist across the political border between the Dominican Republic and Haiti due to the fundamentally different economic and political realities of each country. Relationships in the fossil record confirm that Hispaniola's sociopolitical boundary is not biologically significant but instead represents one imposed on the island's fauna in the past 500 years by colonial activity. Our approach reveals how a paleontological perspective can contribute to concrete management insights.  相似文献   
32.
Conservation science involves the collection and analysis of data. These scientific practices emerge from values that shape who and what is counted. Currently, conservation data are filtered through a value system that considers native life the only appropriate subject of conservation concern. We examined how trends in species richness, distribution, and threats change when all wildlife count by adding so-called non-native and feral populations to the International Union for Conservation of Nature Red List and local species richness assessments. We focused on vertebrate populations with founding members taken into and out of Australia by humans (i.e., migrants). We identified 87 immigrant and 47 emigrant vertebrate species. Formal conservation accounts underestimated global ranges by an average of 30% for immigrants and 7% for emigrants; immigrations surpassed extinctions in Australia by 52 species; migrants were disproportionately threatened (33% of immigrants and 29% of emigrants were threatened or decreasing in their native ranges); and incorporating migrant populations into risk assessments reduced global threat statuses for 15 of 18 species. Australian policies defined most immigrants as pests (76%), and conservation was the most commonly stated motivation for targeting these species in killing programs (37% of immigrants). Inclusive biodiversity data open space for dialogue on the ethical and empirical assumptions underlying conservation science.  相似文献   
33.
土壤中锌的含量异常会阻碍植物生长.海南岛地处热带地区,上壤中锌的含量为1.85~107.89mg/kg,平均31.46mg/kg;0.1mol/L盐酸提取有效锌含量0.50~9.80mg/kg,平均3.86mg/kg.玄武岩上的土壤含锌量为87.35~107.89mg/kg,滨海砂上含锌量大多不足20mg/kg,其它土类的锌含量大多在15~50mg/kg.除了个别土壤锌含量偏低外,绝大多数土壤锌含量是正常的.土壤锌含量的地理分布是:东北部地区明显高,其次是西南部,再次为西北部、中部和东南部地区,岛四周的滨海砂土地区最低.海南岛的土壤锌含量与母质种类的关系最为密切,玄武岩母质上的比花岗岩的高得多.气候条件也是影响锌含量的重要因素之一,湿润地区锌有向下淋溶的趋势.干热地区锌有上移的倾向.质地粘重的土壤含锌量往往较高.土壤有机质对锌含量的影响不明显.  相似文献   
34.
Abstract:  The "botanist effect" is thought to be the reason for higher plant species richness in areas where botanists are disproportionately present as an artefactual consequence of a more thorough sampling. We examined whether this was the case for U.S. counties. We collated the number of species of vascular plants, human population size, and the area of U.S. counties. Controlling for spatial autocorrelation and county area, plant species richness increased with human population size and density in counties with and without universities and/or botanical gardens, with no significant differences in the relation between the two subsets. This is consistent with previous findings and further evidence of a broad-scale positive correlation between species richness and human population presence, which has important consequences for the experience of nature by inhabitants of densely populated regions. Combined with the many reports of a negative correlation between the two variables at a local scale, the positive relation between plant species richness in U.S. counties and human population presence stresses the need for the conservation of seminatural areas in urbanized ecosystems and for the containment of urban and suburban sprawl.  相似文献   
35.
调查发现广州市屋顶自然生长的维管植物有49科109属128种,植物种类较多的科为菊科、禾本科、桑科、景天科、茜草科和鸭跖草科;屋顶自然生长的植物种类数量与环境受污染程度成反比,而与周围植物的多少成正比;屋顶自然生长的植物由于长期适应屋顶的极端环境,形成了的一些独特的生态生物学特征。基于上述结果配置相应的植物组合,设计适于屋顶绿化的生态系统箱、配制相应土壤并进行技术集成,观测其生长和隔热效应。同时进行空白对照、黑网荫蓬对照、生态隔热层对照、普通土壤种植区对比试验,发现生态隔热层和生态系统箱具有成本低、易维持、隔热好、景观美的效果。  相似文献   
36.
Cycles of storm destruction and rebuilding of human facilities are as much a part of a predictable cycle of shoreline change as destruction and re-establishment of landforms and wildlife habitat by natural processes. An evaluation of the human-induced and natural geomorphic responses to three storms in two vulnerable developed areas in New Jersey reveals that storms can have limited effect in re-establishing a natural coastal resource base of lasting significance. Reconstruction of coastal landscapes by human action may be more rapid than natural restoration, decreasing the likelihood for geomorphic features to develop based on natural processes. Reliance on storm processes to create new natural habitat in locations where there is human investment in buildings and support infrastructure is not realistic unless a proactive stance is taken to include naturally-functioning characteristics of the coastal system in reconstruction efforts. By striving to control construction of shorefront buildings to reduce their potential for damage, managers may be taking attention away from the separate but critical issue of ensuring that post-storm reconstruction effort include the potential for replacing loss of natural geomorphic features and wildlife habitat.  相似文献   
37.
38.
城市热岛效应研究进展   总被引:65,自引:8,他引:65  
彭少麟  周凯  叶有华  粟娟 《生态环境》2005,14(4):574-579
作为现代城市气候主要特征之一的城市热岛效应有日渐严重的趋势。文章综述了城市热岛的生态环境效应、热岛的主要形成机制、时空分布特征等研究状况和发展趋势;基于当前城市热岛研究的现状,提出了未来城市热岛效应研究的方向及缓解城市热岛效应的有关对策。  相似文献   
39.
在对西藏雅鲁藏布板块缝合线西段北亚带达机翁蛇绿岩的地质构造、岩石组合等进行野外考察的基础上,首次对该蛇绿岩的主量元素、微量元素、REE及Sr、Pb、Nd同位素进行了较系统的测试分析和综合研究,并由此探讨了该蛇绿岩的构造环境。提出该蛇绿岩为新特提斯东段岛海格局中的岛派成国,为已消亡的中生代新特提斯洋岩石圈的残片。  相似文献   
40.
简述了国家863课题"钢铁窑炉烟尘PM_(2.5)控制技术与装备"的目的、意义和研究成果,介绍了细颗粒物预荷电技术、基于海岛纤维的表面超细过滤材料、预荷电袋滤器、"一阀多喷"清灰等技术的最新进展,通过示范工程的成功运行,验证了成果的先进性和实用性。研究成果将为工业窑炉烟尘细颗粒物深度净化提供技术和装备支撑,适用于新建除尘项目和除尘项目改造。  相似文献   
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