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481.
本文以江英乡为例,阐明了广东石灰岩山区土壤资源的生态环境特点。针对这些特点,我们提出了顺应生态环境、充分发挥小气候优势、推广良种良法、调整农业结构、发展外向型绿色企业以及保水保土等一系列综合开发利用的措施,并在江英乡付诸实施。实践证明,这些措施具有明显的经济效益和社会效益,从而为广东石灰岩山区开发利用土壤资源、发展农业经济提供了参考依据。 相似文献
482.
简述了柴河水库水源涵养对保护水源水质、改善水质的作用;针对柴河水库水源涵养区氮磷污染、面源污染和生态破坏等存在的主要环境问题,提出了可操作性较强的保护措施。 相似文献
483.
This work was conducted to analyse pressing and competingdemands of water in Northeast Sicily, Italy. In thisarea, looking at the Ionian Sea, freshwaters and coastalseawaters have been studied on the quality and on thetransport processes of pollutants. Attention has beenfocused on chemical and microbial parameters proposed byEuropean Directives for drinking freshwaters and bathingseawaters. The findings show that the ground freshwaters areof good quality but the surface ones, particularly torrentsand correlated under-river aquifers, are clearly polluted.The characteristics of the coastal seawaters are accordingwith those of the closely bound up estuarine waters.Contamination is due essentially to discharge of raw sewagein the watercourses by public and private pipes. The impactis usually less evident during the wet season because rainand seastorms dilute the polluting load, but in dry periodsthis pollution causes loss of habitat and deleterious effectson environment. A database has been developed to provide agraphic and mapping display interface of the area studied andto assist the management of the studied fluvial basins. 相似文献
484.
Over the last two decades, urban noise has been increasingrapidly, primarily in urban areas, due to population growthand the increase of certain noise sources. The main objectiveof this paper is to assess the sources and possible impactsof the community noise problems in Lebanese urban areas,particularly the Greater Beirut Area. The causes and effectsof community noise pollution are briefly presented. Soundpressure levels that were measured to define existing noiseexposure levels in various locations in the Greater BeirutArea are also presented. The attitudes toward noise pollutionand perceived annoyance impact on a sample of 1,038 exposedresidents are described. The association between measurednoise levels and sources, as well as annoyance, is examinedusing correlation analysis and linear and multiple linearregressions. A set of recommendations is presented to reducecommunity noise problem in Greater Beirut Area. 相似文献
485.
论农村居民点用地混合利用的研究框架 总被引:1,自引:0,他引:1
土地混合利用倡导不同使用性质/功能用地的混合布局,是提高经济发展活力与土地利用集约度的重要途径。当前,土地混合利用主要应用于城市用地演变与规划实践领域,伴随着城乡互动加剧,城乡界限趋于模糊,经济发达地区的农村居民点用地内部结构与功能逐渐多样化,也呈现显著的混合利用特征。基于此,尝试将土地混合利用应用到农村居民点用地演变与规划中,在回顾土地混合利用理论及其应用的基础上,按照“内涵特征—定量测度—驱动机理—实践路径”的逻辑思路,对经济发达地区的农村居民点用地混合利用进行系统解析,并以天津都市郊区的姚村为例实证本文提出的研究框架,在理论上丰富农村居民点用地转型的内容与方法,在实践中为编制村庄规划、助推乡村振兴提供科学支撑。 相似文献
486.
487.
Connectivity of Streams and Wetlands to Downstream Waters: An Integrated Systems Framework 总被引:1,自引:0,他引:1
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Scott G. Leibowitz Parker J. Wigington Jr. Kate A. Schofield Laurie C. Alexander Melanie K. Vanderhoof Heather E. Golden 《Journal of the American Water Resources Association》2018,54(2):298-322
Interest in connectivity has increased in the aquatic sciences, partly because of its relevance to the Clean Water Act. This paper has two objectives: (1) provide a framework to understand hydrological, chemical, and biological connectivity, focusing on how headwater streams and wetlands connect to and contribute to rivers; and (2) briefly review methods to quantify hydrological and chemical connectivity. Streams and wetlands affect river structure and function by altering material and biological fluxes to the river; this depends on two factors: (1) functions within streams and wetlands that affect material fluxes; and (2) connectivity (or isolation) from streams and wetlands to rivers that allows (or prevents) material transport between systems. Connectivity can be described in terms of frequency, magnitude, duration, timing, and rate of change. It results from physical characteristics of a system, e.g., climate, soils, geology, topography, and the spatial distribution of aquatic components. Biological connectivity is also affected by traits and behavior of the biota. Connectivity can be altered by human impacts, often in complex ways. Because of variability in these factors, connectivity is not constant but varies over time and space. Connectivity can be quantified with field‐based methods, modeling, and remote sensing. Further studies using these methods are needed to classify and quantify connectivity of aquatic ecosystems and to understand how impacts affect connectivity. 相似文献
488.
Alexey O. Pristupa Maria Tysiachniouk Arthur P.J. Mol Rik Leemans Tatiana Minayeva Anastasia Markina 《Journal of Environmental Planning and Management》2018,61(10):1674-1700
In the Russian Arctic, nature protection is important to preserve valuable ecosystems and indigenous lifestyles against the rapidly expanding oil and gas activities. In this regard, zoning legitimately balances influential stakeholders versus weak ones, and can leverage stakeholders to exercise their rights. This study explores how various stakeholders employ zoning in the Numto Nature Park in the oil-rich Russian Khanty-Mansi Autonomous Okrug–Yugra to advance their interests and how they use scientific information to achieve this. Through stakeholder interviews, analysis of electronic media and literature review, we conclude that a participatory and science-based zoning exercise stimulates the necessary deliberation. However, legal ambiguity, deficient law implementation and informal practices limit the zoning's potential to balance stakeholders’ interests. All the stakeholders calculatingly used scientific information to legitimize their own ambitions, activities and claims. Hence, zoning and the underlying information claims should be interpreted as both a resource and a battleground in nature-use conflicts. 相似文献
489.
Alicia Pelegrina-López Francisco M. Ocaña-Peinado Ignacio Henares-Civantos José L. Rosúa-Campos 《Journal of Environmental Planning and Management》2018,61(1):124-142
Protected areas cannot be considered as elements isolated from the human groups that inhabit them. Consideration of the social factor is fundamental to guarantee the success of any management model. In this sense, analyzing the perception of people who live in protected areas can be a key tool for the formulation of proposals for improving the existing models. This article explores perceptions of local residents in the Sierra Nevada Protected Area in Southern Spain and identifies the socio-demographic factors that affect these perceptions. The main objective is to generate relevant data for the protected area management team. The recommendations we can offer entail a review of the communication plan and participatory strategy considering social differences in perceptions of the local population. 相似文献
490.
There is increasing concern about the conservation status of sharks. However, the presence of numerous different (and potentially mutually exclusive) policies complicates management implementation and public understanding of the process. We distributed an online survey to members of the largest professional shark and ray research societies to assess member knowledge of and attitudes toward different conservation policies. Questions covered society member opinions on conservation and management policies, personal histories of involvement in advocacy and management, and perceptions of the approach of conservation nongovernmental organizations (NGOs) to shark conservation. One hundred and two surveys were completed (overall response rate 21%). Respondents considered themselves knowledgeable about and actively involved in conservation and management policy; a majority believed scientists have a responsibility to advocate for conservation (75%), and majorities have sent formal public comments to policymakers (54%) and included policy suggestions in their papers (53%). They believe sustainable shark fisheries are possible, are currently happening today (in a few places), and should be the goal instead of banning fisheries. Respondents were generally less supportive of newer limit‐based (i.e., policies that ban exploitation entirely without a species‐specific focus) conservation policy tools, such as shark sanctuaries and bans on the sale of shark fins, than of target‐based fisheries management tools (i.e., policies that allow for sustainable harvest of species whose populations can withstand it), such as fishing quotas. Respondents were generally supportive of environmental NGO efforts to conserve sharks but raised concerns about some NGOs that they perceived as using incorrect information and focusing on the wrong problems. Our results show there is an ongoing debate in shark conservation and management circles relative to environmental policy on target‐based natural resources management tools versus limit‐based conservation tools. They also suggest that closer communication between the scientific and environmental NGO communities may be needed to recognize and reconcile differing values and objectives between these groups. 相似文献