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111.
中国水土流失研究热点区的空间分布制图   总被引:1,自引:0,他引:1  
胡云锋  韩月琪  曹巍  张云芝 《生态学报》2019,39(16):5829-5835
中国是世界上水土流失最为严重的国家之一。准确掌握既有水土流失研究的空间分布格局是一项基础性工作。以中国知网学术期刊数据库作为数据源,应用自然语言处理方法,对1980—2017年中国水土流失研究地区进行了地名信息提取及研究热点建模;继而应用RUSLE模型模拟,得到全国土壤侵蚀强度的空间分布;在上述研究基础上,对研究热点地区与侵蚀强度之间的空间耦合关系进行了对比分析。结果表明:(1)1980年以来,中国水土流失研究热点区主要分布在黄土高原及贵州高原,涉及陕西、宁夏、内蒙古、甘肃、贵州以及黑龙江等省区;中等及以上热度的县(区、市)共171个,占全国国土总面积的5.33%。(2)RUSLE模型模拟表明,严重的土壤侵蚀主要分布在黄土高原及云贵高原,涉及陕西、宁夏、甘肃、山西、贵州、云南、四川等省区;侵蚀模数大于20 t hm~(-2) a~(-1)的县(区、市)共251个,占全国国土总面积的7.04%。(3)研究热点地图与水土流失强度模型模拟地图之间存在空间差异。对特定空间耦合模式的分析有助于判断科研资源配置的合理性。  相似文献   
112.
Healthcare is a critical service sector with a sizable environmental footprint from both direct activities and the indirect emissions of related products and infrastructure. As in all other sectors, the “inside‐out” environmental impacts of healthcare (e.g., from greenhouse gas emissions, smog‐forming emissions, and acidifying emissions) are harmful to public health. The environmental footprint of healthcare is subject to upward pressure from several factors, including the expansion of healthcare services in developing economies, global population growth, and aging demographics. These factors are compounded by the deployment of increasingly sophisticated medical procedures, equipment, and technologies that are energy‐ and resource‐intensive. From an “outside‐in” perspective, on the other hand, healthcare systems are increasingly susceptible to the effects of climate change, limited resource access, and other external influences. We conducted a comprehensive scoping review of the existing literature on environmental issues and other sustainability aspects in healthcare, based on a representative sample from over 1,700 articles published between 1987 and 2017. To guide our review of this fragmented literature, and to build a conceptual foundation for future research, we developed an industrial ecology framework for healthcare sustainability. Our framework conceptualizes the healthcare sector as comprising “foreground systems” of healthcare service delivery that are dependent on “background product systems.” By mapping the existing literature onto our framework, we highlight largely untapped opportunities for the industrial ecology community to use “top‐down” and “bottom‐up” approaches to build an evidence base for healthcare sustainability.  相似文献   
113.
Drought, widely studied as an important driver of ecosystem dynamics, is predicted to increase in frequency and severity globally. To study drought, ecologists must define or at least operationalize what constitutes a drought. How this is accomplished in practice is unclear, particularly given that climatologists have long struggled to agree on definitions of drought, beyond general variants of “an abnormal deficiency of water.” We conducted a literature review of ecological drought studies (564 papers) to assess how ecologists describe and study drought. We found that ecologists characterize drought in a wide variety of ways (reduced precipitation, low soil moisture, reduced streamflow, etc.), but relatively few publications (~32%) explicitly define what are, and are not, drought conditions. More troubling, a surprising number of papers (~30%) simply equated “dry conditions” with “drought” and provided little characterization of the drought conditions studied. For a subset of these, we calculated Standardized Precipitation Evapotranspiration Index values for the reported drought periods. We found that while almost 90% of the studies were conducted under conditions quantifiable as slightly to extremely drier than average, ~50% were within the range of normal climatic variability. We conclude that the current state of the ecological drought literature hinders synthesis and our ability to draw broad ecological inferences because drought is often declared but is not explicitly defined or well characterized. We suggest that future drought publications provide at least one of the following: (a) the climatic context of the drought period based on long‐term records; (b) standardized climatic index values; (c) published metrics from drought‐monitoring organizations; (d) a quantitative definition of what the authors consider to be drought conditions for their system. With more detailed and consistent quantification of drought conditions, comparisons among studies can be more rigorous, increasing our understanding of the ecological effects of drought.  相似文献   
114.
Effective natural resource management requires knowledge exchange between researchers and managers to support evidence‐based decision‐making. To achieve this, there is a need to align research with management and policy needs. This project aimed to identify the flow‐related ecological knowledge needs for freshwater fish to better inform environmental water management in the Murray–Darling Basin, south‐eastern Australia. Our major objective was to provide an up‐to‐date assessment of scientific research and integrate this with the knowledge requirements of relevant managers to guide future research. We reviewed the contemporary scientific literature and engaged managers specifically responsible for delivering flows for fish outcomes via a questionnaire and workshop. Research on fishes of the MDB has generally evolved from single locations and/or times to larger spatio‐temporal scales, including multiple sites, rivers and catchments. There has also been a trend from single life stage studies to incorporation of multiple life stages and population processes. There remain, however, significant deficiencies in knowledge for most native species, many of which are threatened. Four agreed key knowledge gaps were derived from the literature review and managers’ suggestions: (i) population dynamics, (ii) movement, dispersal and connectivity, (iii) survival and recruitment to adults and (iv) recruitment drivers. To inform policy and management, managers desired timely advice, based on robust research and monitoring. Fish species of most relevance to managers were those highly regarded by community stakeholders and whose life histories and population dynamics are potentially influenced by flow. Populations of these mostly large‐bodied, angling species (e.g. Murray Cod, Golden Perch and Silver Perch) have declined, often due to river regulation and, in conjunction with managers’ priorities, are relevant candidates for research to support the management of flow to rehabilitate fish populations in the MDB.  相似文献   
115.
The central focus of this study is a learning method in which university students produce instructional videos about the content matter as part of their learning process, combined with other learning assignments. The rationale for this is to promote a more multimodal pedagogy, and to provide students opportunities for a more learner-centred, motivating, active, engaging and productive role in their learning process. As such we designed a ‘video course’ where the students needed to produce an instructional video which could be used for university teaching. In addition to producing the video, the students needed to write a literature review of the topic of the video and a learning journal. At the end of the course the students filled a questionnaire regarding their learning and emotions during the project. Based on the students’ subjective answers, it appeared that producing a video, combined with writing the literature review can be an efficient way of learning. Most students found the project emotionally very positive and regarded it motivating to work on a video which they knew will have use in the future. This research suggests that a multimodal video project in a higher education setting enhances learning through increased motivation and positive emotions.  相似文献   
116.
通过维普中文期刊网和英文ScienceDirect数据库有关种群、种群生态和种群行为文献的查询,发现文献的发表量很不平衡,种群研究文献的年增长率远大于种群生态和种群行为。英文文献中关于种群行为研究的文献增长率高于种群生态,而中文文献正好相反。  相似文献   
117.
为了解我国食药用菌资源的开发利用情况,需要对我国食药用菌栽培驯化情况进行统计分析。通过公共数据库关键词搜索,统计栽培驯化食药用菌种类,经过拉丁名以及中文名称的核实,本名录收录了192种驯化栽培的食药用菌,隶属于2门15目48科89属,包括子囊菌门(Ascomycota) 26个种,担子菌门(Basidiomycota)166个种,其中在科水平上,多孔菌科(Polyporaceae)、蘑菇科(Agaricaceae)、侧耳科(Pleurotaceae)以及泡头菌科(Physalacriaceae)种类最多;在属水平,侧耳属(Pleurotus)、蘑菇属(Agaricus)、木耳属(Auricularia)、灵芝属(Ganoderma)等栽培驯化种类较多。通过本名录发现,我国已经完成栽培驯化的食用菌种类繁多,还有大量食药用菌有开发利用前景。  相似文献   
118.
The rise in research investigating fragmentation and its impact on primates and other taxa reflects the growing presence of fragmented landscapes themselves. Although numerous studies report the negative effects of fragmentation on biodiversity, it is difficult to generalize responses to fragmentation for specific taxonomic groups, such as non-human primates, when studies have not employed a definitive concept of fragmentation or fragments themselves. Madagascar's high degree of fragmentation, wealth of endemic taxa, and extensive history of ecological research provide the opportunity to compare fragmentation studies across similar contexts. We conducted a literature search of peer-reviewed articles on fragmentation in Madagascar to characterize its trends. A total of 70 articles, 46 of which concentrated on lemurs, tested the impacts of fragmentation on Malagasy taxa, while additional sources conducted research in one or more fragments without testing its effects (n = 112 total, 79 on lemurs). Studies on lemurs most frequently tested fragmentation's impacts on genetics and biodiversity metrics (n = 16 and 15 studies, respectively), although health, modeling, behavioral, and cross-disciplinary techniques were also reported. Responses to fragmentation were reported for 49 lemur species, with most studies concentrated in eastern Madagascar (87%). Although there was variation in the metrics reported in studies testing the effects of fragmentation on Malagasy species, the most common measures were fragment area, isolation, or comparison to a control site. Landscape-scale approaches and examination of fragmentation per se were rarely employed. Characterizing trends of fragmentation research in Madagascar emphasizes the challenges of documenting fragmentation's effects while highlighting the benefits of research within fragmented landscapes, particularly when combined with consideration for how the matrix within human-modified landscapes may impact primate populations.  相似文献   
119.
Scholars in the natural sciences rely on historic literature more than any other branch of science. Yet much of this material has limited global distribution and much of it is available in only a few select libraries. This wealth of knowledge is availahle only to those few who can gain direct access to significant library collections, a situation that is considered one of the chief impediments to the efficiency of research in the field. Community support and new technologies led to the formation of the Biodiversity Heritage Library. The BHL is an international collaboration of natural history libraries working together to make biodiversity literature available for use by the widest possible audience through open access and sustainable management.  相似文献   
120.
Abstract

Atherosclerosis is a life-threatening disease and a major cause of mortalities worldwide. While many of the atherosclerotic sequelae are reflected as microvascular effects in the eye, the molecular mechanisms of their development is not yet known. In this study, we employed a systems biology approach to unveil the most significant events and key molecular mediators of ophthalmic sequelae caused by atherosclerosis. Literature mining was used to identify the proteins involved in both atherosclerosis and ophthalmic diseases. A protein–protein interaction (PPI) network was prepared using the literature-mined seed nodes. Network topological analysis was carried out using Cytoscape, while network nodes were annotated using database for annotation, visualization and integrated discovery in order to identify the most enriched pathways and processes. Network analysis revealed that mitogen-activated protein kinase 1 (MAPK1) and protein kinase C occur with highest betweenness centrality, degree and closeness centrality, thus reflecting their functional importance to the network. Our analysis shows that atherosclerosis-associated ophthalmic complications are caused by the convergence of neurotrophin signaling pathways, multiple immune response pathways and focal adhesion pathway on the MAPK signaling pathway. The PPI network shares features with vasoregression, a process underlying multiple vascular eye diseases. Our study presents a first clear and composite picture of the components and crosstalk of the main pathways of atherosclerosis-induced ocular diseases. The hub bottleneck nodes highlight the presence of molecules important for mediating the ophthalmic complications of atherosclerosis and contain five established drug targets for future therapeutic modulation efforts.  相似文献   
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