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431.
以永定河北京段2019~2020年的生态补水为例,通过室内混合实验和淋滤实验研究河水下渗对地下水质量的影响.结果表明,水化学指标的种类与下渗前相比无变化,水-岩相互作用对指标浓度的改变作用也比较有限,指标的浓度水平总体上介于河水和地下水之间.下渗水对地下水质量的改变作用从根本上取决于河水与地下水的质量差异和河水的补给量...  相似文献   
432.
运用城市生态规划的原理及方法,对吴家山城区绿地进行了规划。包括城市的组团式规划、控制性组分规划、非控制性组分规划、生态平衡构架规划四部分。通过规划,实现吴家山生态城市景观结构和功能的匹配及能流、物流的畅通,使绿地系统上升成为城市生态环境质量的调控系统来建设。  相似文献   
433.
论可持续发展的物质体系   总被引:6,自引:0,他引:6  
可持续发展的物质体系包括资源、环境和生态。可持续发展的终极基础是资源物质变换,可持续发展的生存依托是环境,可持续发展的动态载体是生态平衡网络。本文通过分析资源、环境和生态之间的关系与相互作用,提出了可持续发展的基础是物质体系的观点。  相似文献   
434.
The interaction of man and nature is considered in terms of classical ecology, which is becoming a synthetic systemic science based on a set of other sciences. The divisions of modern human ecology that deal with different organizational levels of ecological systems have been developed to different degrees. Attention is given to the necessity of discrediting the mechanistic concept of opposition between man and nature and taking into account the specific ecological functions of man related to group adaptation (culture), as well as the global role of all living organisms in the maintenance of environmental conditions on Earth.  相似文献   
435.
The natural range of variation of ecosystems provides reference conditions for sustainable management and biodiversity conservation. We review how the understanding of natural reference conditions of boreal forests in northern Europe has changed from earlier perceptions of even-aged dynamics driven by stand-replacing disturbances towards current understanding highlighting the role of non-stand-replacing disturbances and the resultant complex forest dynamics and structures. We show how earlier views and conceptual models of forest disturbance dynamics, including the influential ASIO model, provide estimates of reference conditions that are outside the natural range of variation. Based on a research synthesis, we present a revised forest reference model incorporating the observed complexity of ecosystem dynamics and the prevalence of old forests. Finally, we outline a management model and demonstrate its use in forest ecosystem management and show how regional conservation area needs can be estimated. We conclude that attaining favourable conservation status in northern Europe’s boreal forests requires increasing emphasis on ecosystem management and conservation for old forest characteristics.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01444-3) contains supplementary material, which is available to authorized users.  相似文献   
436.
长江流域城市生态环境问题与跨世纪持续发展战略   总被引:10,自引:2,他引:10  
综合分析评价了长江流域城市的生态环境态势与问题,城市水环境依然恶化,特别是城市内河道,湖泊水质多污染严重。城市大气污染仍是加重趋向,一些特大城市汽车尾气污染上升,城市酸雨依然严重。城市生态问题沉重,绿地不足,热岛加重,地面沉降,水土流失等。沉重的生态环境赤字已深刻影响到城市经济社会的发展。面对二十一世纪,论证了长江流域城市发展战略,走城市可持续发展之路是唯一战略选择,而建设现代化的山水园林生态城市  相似文献   
437.
Functional agrobiodiversity (FAB) has severely declined during the last decades. Current efforts to reinforce FAB are mainly focused on single-actor, parcel-based measures, whereas multi-actor landscape approaches are supposed to be more effective. In this paper, we propose a social–ecological framework that structures how different land users at both the parcel and landscape level interact with FAB as a natural resource. Furthermore, we introduce 1 m2 FAB gardens as an interactive multipurpose measurement tool to gather data on ecosystem services in collaboration with land users. The presented action research approach provides new insights on motivations and interests of different land users in FAB and how knowledge exchange can result in a higher motivation to invest in FAB. Using a case study in Flanders, we illustrate the FAB-garden concept and highlight its strengths and necessary considerations to properly complement other research approaches in this social–ecological system.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01382-0) contains supplementary material, which is available to authorized users.  相似文献   
438.
Urban and exurban expansion results in habitat and biodiversity loss globally. We hypothesize that a coupled-model approach could connect urban planning for future cities with landscape ecology to consider wildland habitat connectivity. Our work combines urban growth simulations with models of wildlife corridors to examine how species will be impacted by development to test this hypothesis. We leverage a land use change model (SLEUTH) with structural and functional landscape-connectivity modeling techniques to ascertain the spatial extent and locations of connectivity related threats to a national park in southern Arizona, USA, and describe how protected areas might be impacted by urban expansion. Results of projected growth significantly altered structural connectivity (80%) when compared to current (baseline) corridor conditions. Moreover, projected growth impacted functional connectivity differently amongst species, indicating resilience of some species and near-complete displacement of others. We propose that implementing a geospatial-design-based model will allow for a better understanding of the impacts management decisions have on wildlife populations. The application provides the potential to understand both human and environmental impacts of land-system dynamics, critical for long-term sustainability.  相似文献   
439.
A new approach was developed to evaluate the implications of the spatiotemporal variability of green vegetation for the dispersion of livestock that is required to access quality forage in semi-arid Africa. Maximum NDVI (Normalized Difference Vegetation Index) at 1 km2 resolution was determined for concentric rings (0–31 km radii) around 227 individual sample locations within the study area for 14 dates (between 1 April to 1 November) annually over the 2000–2010 period. A sigmoidal curve was fitted to points within the maximum NDVI × distance radii space to determine the asymptote distance (AD) – the radius at which further dispersion from the sample location does not lead to significant gains in access to green forage. AD was found to: increase with latitude (or increasing aridity); decline as the rainy season proceeds; and show no trend over the 2000–2010 period. These results introduce much-needed empirical data to current debates surrounding the scales of governance to support livestock mobility.  相似文献   
440.
For land-use science to engage the general public it must successfully translate its concepts and conclusions and make them public outside of traditional scientific venues. Here we explore science-art exhibits, which blend artistic presentations with specific scientific data or themes, as a possible effective way of communicating scientific information and disrupting misconceptions. We describe the process of producing a science-art exhibit on remote sensing and Puerto Rican landscape history from 1937 to the present, sited at a rural Puerto Rican community museum, and examine the visitor experience and educational outcomes of the museum exhibit through analysis of survey data. The exhibit project engaged undergraduate students from a variety of academic backgrounds, introduced land-use science concepts to the public in an engaging format, and was effective at reshaping visitors’ misconceptions of Puerto Rico’s landscape change history.  相似文献   
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