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321.
九寨沟钙华是距今约3万年(特别是1万年)以来逐渐形成的。大规模的钙华沉积是湖泊、滩流、瀑布、泉及台地景观形成的基础,覆盖核心景区2.4 km2的面积。钙华景观是九寨沟遗产地突出普遍价值——\"自然美学价值\"的核心,是景区的关键吸引力。为九寨沟的持续保护和为未来研究提供支持,本文从钙华沉积物、钙华景观成因、钙华景观变化及其原因、钙华景观保护恢复的角度,总结了公开和未公开发表的研究结果。针对目前钙华景观保护面临的主要问题(钙华退化、藻类生物量增加、沼泽化),本文归纳了相关的自然与人为因素,包括气候变暖、大气沉降、水化学变化、旅游活动、森林采伐、地质灾害等;归纳了地震和滑坡等地质灾害对钙华景观形成与重塑的双重作用;总结了钙华景观保护恢复的管理工作及其成效。本文提出未来可重点研究:(1)气候变化和人为活动背景下多圈层(大气、陆地生态系统、水生生态系统和基岩系统)对水体氮、磷、溶解性有机物、绿藻生物量、钙华沉积与溶蚀的影响机制及程度;(2)2017年九寨沟7.0级地震后,自然与人为干预下钙华微地貌的长期稳定性,水土流失加剧对湖泊透明度、钙华、沼泽化及美学价值的长期影响,地质灾害及其防治对钙华景观的长期效应。  相似文献   
322.
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Large‐scale change in human values and associated behavior change is believed by some to be the ultimate solution to achieve global biodiversity conservation. Yet little is known about the dynamics of values. We contribute to this area of inquiry by examining the trajectory of values affecting views of wildlife in North America. Using data from a 19‐state study in the United States and global data from the Schwartz Value Survey, we explored questions of value persistence and change and the nature of attitudinal responses regarding wildlife conservation issues. We found support, based on subjects’ ancestry, for the supposition that domination is a prevalent American value orientation toward wildlife that has origins in European Judeo‐Christian traditions. Independent of that effect, we also found indications of change. Modernization is contributing to a shift from domination to mutualism value orientations, which is fostering attitudes less centered on human interests and seemingly more consistent with a biocentric philosophy. Our findings suggest that if value shift could be achieved in a purposeful way, then significant and widespread behavior change believed necessary for long‐term conservation success may indeed be possible. In particular, greater emphasis on mutualism values may help provide the context for more collaborative approaches to support future conservation efforts. However, given the societal forces at play, it is not at all clear that human‐engineered value shift is tenable. Instead of developing strategies aimed at altering values, it may be more productive to create strategies that recognize and work within the boundaries of existing values. Whereas values appear to be in a period of flux, it will be difficult to predict future trends without a better understanding of value formation and shift, particularly under conditions of rapid social‐ecological change.  相似文献   
323.
    
Attempts to better understand the social context in which conservation and environmental decisions are made has led to increased interest in human social networks. To improve the use of social-network analysis in conservation, we reviewed recent studies in the literature in which such methods were applied. In our review, we looked for problems in research design and analysis that limit the utility of network analysis. Nineteen of 55 articles published from January 2016 to June 2019 exhibited at least 1 of the following problems: application of analytical methods inadequate or sensitive to incomplete network data; application of statistical approaches that ignore dependency in the network; or lack of connection between the theoretical base, research question, and choice of analytical techniques. By drawing attention to these specific areas of concern and highlighting research frontiers and challenges, including causality, network dynamics, and new approaches, we responded to calls for increasing the rigorous application of social science in conservation.  相似文献   
324.
依靠科技进步 发展低碳农业   总被引:14,自引:0,他引:14  
在全球携手应对气候变暖、减少温室气体排放的背景下,发展低碳经济是解决气候变化与经济发展矛盾的有效途径。通过描述气候变化、固碳减排对粮食安全、土壤碳汇、森林固碳、资源循环利用等影响和促进作用,深入分析发展低碳经济与可持续发展的关系,探讨如何在农业领域内开发高效循环生产体系,从而实现农业生产过程的固碳减排目的。由此,提出发展低碳农业是实现低碳经济的目标之一,它是一个复合技术体系,涉及了绿色农业、循环农业、生态文明、可持续发展理念。必须通过科学技术的突破,改造、提升低碳农业技术,改变农业现有的"高能耗、高污染"的生产状况,实现低碳生产、生活方式的转变。最后提出发展现代的低碳农业产业经济的对策和思考。  相似文献   
325.
    
Regional ecosystem monitoring is a central form of knowledge sharing and collaboration amongst scientists and decision makers on environmental health, land use change, and science-policy development. Despite the proliferation of such research networks on long-term monitoring on many continents, little has been achieved in Africa. This study aims to assess and examine the spatiotemporal trend and categorical patterns in ecosystem monitoring-related research in Africa for the benefits of conserving biodiversity and sustaining natural resource sectors for well-being and livelihood security, environmental planning, and ecological stewardship. A systematic review was conducted using bibliometric tools. Based on a set of search terms and peer-reviewed publications retrieved from various ecosystem monitoring networks and journal databases, further analysis was conducted using social network approaches, mapping tools, and content analysis. About 1442 scientific publications on ecosystem monitoring and related research were documented from 1987 to 2014 mostly published in English. The number of publication increased progressively since 1992 after the Convention on Biodiversity was signed and this trend peaked till 2008. South African Journal of Science was the most leading journal and Nature the most cited. Internationally coauthored and collaborative articles represented majority of the findings with the United Kingdom at the central position in the research network due to colonial relationships. Regional collaboration amongst countries is limited owing to language barriers and other institutional constraints such as funding and short-term projects. These findings have implication for prioritizing national and regional policies toward biodiversity science and its contribution to human well-being, food security, and global change responses.  相似文献   
326.
    
Understanding human behavior is vital to developing interventions that effectively lead to proenvironmental behavior change, whether the focus is at the individual or societal level. However, interventions in many fields have historically lacked robust forms of evaluation, which makes it hard to be confident that these conservation interventions have successfully helped protect the environment. We conducted a systematic review to assess how effective nonpecuniary and nonregulatory interventions have been in changing environmental behavior. We applied the Office of Health Assessment and Translation systematic review methodology. We started with more than 300,000 papers and reports returned by our search terms and after critical appraisal of quality identified 128 individual studies that merited inclusion in the review. We classified interventions by thematic area, type of intervention, the number of times audiences were exposed to interventions, and the length of time interventions ran. Most studies reported a positive effect (n = 96). The next most common outcome was no effect (n = 28). Few studies reported negative (n = 1) or mixed (n = 3) effects. Education, prompts, and feedback interventions resulted in positive behavior change. Combining multiple interventions was the most effective. Neither exposure duration nor frequency affected the likelihood of desired behavioral change. Comparatively few studies tested the effects of voluntary interventions on non-Western populations (n = 17) or measured actual ecological outcome behavior (n = 1). Similarly, few studies examined conservation devices (e.g., energy-efficient stoves) (n = 9) and demonstrations (e.g., modeling the desired behavior) (n = 5). There is a clear need to both improve the quality of the impact evaluation conducted and the reporting standards for intervention results.  相似文献   
327.
    
I argue that the dynamic nature of contemporary, landscape-shaping (geomorphic) processes deserves more consideration in conservation science and practice. In an analysis of a sample of fundamental terms related to geomorphology and area-based conservation in the Web of Science, I found that the terms co-occurred in <2% of the analyzed entries (titles, abstracts, and keywords) from 2000 to 2020. This result is indicative of the rather peripheral attention that, more broadly, landscape-shaping processes seem to receive in the conservation literature. Among conservation scientists and practitioners, landforms that define the physical structure of habitat are often perceived as largely static, whereas the consideration of their dynamic adjustments to geomorphic processes is often limited to extreme events. I use examples derived from river-floodplain environments to illustrate strong, multifaceted, and reciprocal interactions between biota and various erosional and depositional processes. These ubiquitous interdependencies clearly demonstrate that geomorphic processes are an integral part of ecosystem dynamics at time scales relevant for conservation. Crucially, erosional and depositional processes modulate many environmental impacts of past and current anthropogenic activities. I conclude that the absence of a more explicit and widespread consideration of geomorphic processes in conservation science and practice is surprising and detrimental to their effectiveness. I call for bolstered efforts among the conservation and geoscience communities to better integrate landscape dynamics within the field of conservation. The rise of the ecosystem-based and social-ecological systems approaches to conservation and the growth of interdisciplinary geoscience branches (e.g., biogeomorphology, ecohydraulics, and geoconservation) will facilitate such an integration.  相似文献   
328.
杨树排放碳氢化合物的相关因素   总被引:7,自引:1,他引:7  
白郁华  李金龙 《环境化学》1995,14(2):118-123
采用封闭式气袋采样和气相色谱法,对杨树排放碳氢化合物(HCs)的情况进行了调查,结果发现,与油松排放情况不同,杨树主要排放异戊二烯,约占其HCs排放总量的95%以上,且与温度,光强正相关,排放的日变化表明,杨树在正午有一排放高峰,夜间基本不排放,在春季和夏季日均气温分别为19.2℃和28.8℃,杨树的异戊二烯平均总排放速率分别为4.4和39.8μg/g.h。  相似文献   
329.
SUMMARY

The search for innovative methods for improving relations between parks and people has led to various conservation and development projects around the world. Nepal's almost three decades of experience in park management in a variety of institutional settings offers valuable lessons in the challenges and opportunities for enlisting local support for conservation. Citing several macro and micro-level case studies from around the country, this paper provides a comparative perspective on the significance of tourism-focused conservation and community development activities in resolving conflicts between parks and local people.  相似文献   
330.
    
《Sustainable Development》2018,26(4):415-421
Release of carbonaceous aerosols – comprising black carbon (BC) and organic carbon (OC) – from biomass burning into the atmosphere is dependent on the burning conditions as to the resultant relative abundances of the emitted BC and OC. This provides a way of managing biomass burning in terms of manipulating the types of emitted aerosol. The carbonaceous aerosols are concerned in different ways in different scientific fields. The BC and OC exert complex implications for (a) radiative forcing in climate change science but (b) public health concern in air pollution science. Referring to these complex implications, a case of sustainability is constructed, which is being unsustainably dealt with at the crossroads of the sciences. This reveals an inadequacy of the reductionist mode of enquiry, necessitating a new mode with unique epistemological orientation for the scholarship of sustainability. The necessity of integration of perspectives that are currently segregated for this sustainability issue and the implications for sustainable development are elucidated. Copyright © 2018 John Wiley & Sons, Ltd and ERP Environment  相似文献   
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