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91.
Fredrik Dalerum 《Ambio》2014,43(7):839-846
Humans are altering their living environment to an extent that could cause environmental collapse. Promoting change into environmental sustainability is therefore urgent. Despite a rapid expansion in conservation biology, appreciation of underlying causes and identification of long-term solutions have largely been lacking. I summarized knowledge regarding the environmental crisis, and argue that the most important contributions toward solutions come from economy, political sciences, and psychology. Roles of conservation biology include providing environmental protection until sustainable solutions have been found, evaluating the effectiveness of implemented solutions, and providing societies with information necessary to align effectively with environmental values. Because of the potential disciplinary discrepancy between finding long-term solutions and short-term protection, we may face critical trade-offs between allocations of resources toward achieving sustainability. Since biological knowledge is required for such trade-offs, an additional role for conservation biologists may be to provide guidance toward finding optimal strategies in such trade-offs.  相似文献   
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93.
Introduced Birds and the Fate of Hawaiian Rainforests   总被引:3,自引:0,他引:3  
Abstract:  The Hawaiian Islands have lost nearly all their native seed dispersers, but have gained many frugivorous birds and fleshy-fruited plants through introductions. Introduced birds may not only aid invasions of exotic plants but also may be the sole dispersers of native plants. We assessed seed dispersal at the ecotone between native- and exotic-dominated forests and quantified bird diets, seed rain from defecated seeds, and plant distributions. Introduced birds were the primary dispersers of native seeds into exotic-dominated forests, which may have enabled six native understory plant species to become reestablished. Some native plant species are now as common in exotic forest understory as they are in native forest. Introduced birds also dispersed seeds of two exotic plants into native forest, but dispersal was localized or establishment minimal. Seed rain of bird-dispersed seeds was extensive in both forests, totaling 724 seeds of 9 native species and 2 exotics with over 85% of the seeds coming from native plants. Without suitable native dispersers, most common understory plants in Hawaiian rainforests now depend on introduced birds for dispersal, and these introduced species may actually facilitate perpetuation, and perhaps in some cases restoration, of native forests. We emphasize, however, that restoration of native forests by seed dispersal from introduced birds, as seen in this study, depends on the existence of native forests to provide a source of seeds and protection from the effects of ungulates. Our results further suggest that aggressive control of patches of non-native plants within otherwise native-dominated forests may be an important and effective conservation strategy.  相似文献   
94.
95.
采用机械淋滤/厌氧生物组合工艺,充分发挥机械淋滤反应器的水解酸化功能和厌氧生物反应器的产甲烷功能,对有机生活垃圾进行了中试规模处理。厌氧生物反应器经过接种,15 d驯化完成。厌氧反应器出水回流淋洗水量对机械淋滤反应器运行特征有较大影响,当回流淋洗水量为3.0 m3/d时,淋滤液COD、VFA第8天时浓度分别为41 000 kg/L和2 000 kg/L。对机械淋滤反应器/厌氧反应器组合工艺进行了多批次实验,每吨有机生活垃圾平均产生沼气87.2 m3,甲烷含量稳定在75%,平均产沼系数为0.46 m3/kg COD,厌氧生物反应器出水COD平均值为560 mg/L,在对有机生活垃圾处理的同时实现有机生活垃圾资源化利用。  相似文献   
96.
The Strategic Plan for Biodiversity 2011–2020 recognizes the increasing importance of scientific knowledge to support conservation policies and decision making. In this study, we assessed the tendency of such knowledge in the first decade of the 21st century. We carried out a systematic review of publications in biodiversity conservation, considering the following aspects: type of research, main topic of study, object of study (i.e. biodiversity organizational level, taxonomic groups and ecosystems), pressures and drivers of change, as well as geographical distribution. In total, 966 publications were analyzed within the three journals with higher academic reach in the field under study: Biodiversity & Conservation, Biological Conservation, and Conservation Biology. Our results show that there are several biases in scientific knowledge associated with the object of study, and analyzed drivers of changes, as well as geographical distribution. However, research trends are not uniform along the first decade of 21st century, as there are some differences between 2000 and 2011 regarding the main topic of the study, the spatial scale and geographical region, and the analyzed ecosystems. We finally discuss the implications of current knowledge trends in biodiversity conservation for achieving the targets delineated by the Strategic Plan for Biodiversity 2011–2020.  相似文献   
97.
生活垃圾机械-生物预处理工艺优化   总被引:1,自引:0,他引:1  
以宜昌市垃圾综合处理场为例,分析了通风量和水分对生物预处理的影响,进而优化生物预处理的实际应用工艺。实验结果表明:通风量与水分对预处理过程中堆体温度、pH、堆高变化影响明显,对挥发分变化影响不明显。选取每30 min风机送风8 min的通风方式,处理之前调整垃圾水分在40%~50%之间,可以取得较好的预处理效果。  相似文献   
98.
海洋微生物多样性的研究进展   总被引:7,自引:0,他引:7  
介绍了海洋微生物多样性研究的意义,综述了国内外开展海洋微生物多样性的主要研究方法和原理。重点介绍了分子生物学技术在研究中的应用,对序列分析和指纹图谱、分子标记、分子探针等方法进行了详细的阐述。  相似文献   
99.
随着好氧污泥颗粒化技术的兴起,好氧颗粒污泥成为研究的热点之一。各国学者对好氧颗粒污泥应用了不同的表征手段,文章对好氧颗粒污泥的物理性质表征方法、物化性质表征方法、生化性质表征方法、性能参数表征方法以及PCR、FISH、DGGE等现代分子生物学技术在好氧颗粒污泥研究中的应用进行了综述。  相似文献   
100.
This article describes an approach to assessing spatial and temporal land-use and land-cover changes in and adjacent to protected areas and to the measurement of landscape stability within a protected area. Methods employed include aerial photographic interpretation and GIS technology. Odum's four-compartment ecosystem model provides the conceptual framework for assessing landscape stability. The study area is a selected sample of the Upper San Pedro National Riparian Conservation Area in the high desert grassland of southeastern Arizona. Significant changes were observed in the landscape matrix and riparian ecosystem. However, when these changes were assessed in the context of Odum's model, the change was nonsignificant. Implications of the approach and potential applications in protected area management are discussed.  相似文献   
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