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41.
Carbon markets and climate finance payments are being used to incentivize the mitigation of CO2 arising from anthropogenic land-use change in forests, marine ecosystems, and lowland grasslands. However, no such consideration has been given to how these ‘carbon finance incentives’ might be applied to mountain grasslands and shrublands, ecosystems that contain a substantial amount of carbon. These incentives amount to more than US$350 billion per annum and could potentially support underfunded natural resource management (NRM) activities, which are urgently needed to address numerous stressors impacting these important ecosystems. In the mountain context, NRM activities could include adaptive grazing management, sustainable cropping, ecosystem preservation, ecosystem restoration, and engineered soil conservation measures. This article investigates the stressors, challenges, and priorities related to the NRM of carbon stocks in mountain grasslands and shrublands; why carbon markets and climate finance have not yet been utilized in this context; and, what is required to position mountain-based NRM activities as eligible for carbon finance incentives. Using surveys and interviews triangulated with a systematic literature review, the study found that carbon finance incentives are not well understood, both amongst mountain-focused experts and in the literature. The study also found the required technical methodologies, policy frameworks, and data to be largely undeveloped. This article proposes a top-down conceptual policy framework that can be used to develop key ‘enabling factors’ with the view of extending the eligibility of carbon markets and climate finance to NRM activities undertaken in mountain grasslands and shrublands in the same way that has been afforded to other ecosystems.

Policy relevance

This is the first study to explicitly highlight the important role that the mountain grasslands and shrublands might play in international climate policy, and how carbon finance mechanisms might support better NRM in these areas. It is also the first to investigate why these incentives have not been adopted thus far. The article concludes by proposing a novel top-down ‘carbon incentive enabling’ framework that could be driven by governments and mountain development focused organizations so as to capture some of the opportunities offered by carbon-based incentives, and help meet international climate policy objectives.  相似文献   

42.
Consideration of environmental flows in river basin management poses great challenges. Environmental flows are interpreted as the natural or regulated releases of water needed in a river to maintain specified valued features of the river ecosystems. This has never been considered explicitly in water resources management of a river basin. An attempt is, therefore, made here to reflect the perception and implications of environmental flows in water resources management. Assessment approaches are reviewed in the context of flow characteristics of a river system and recommendations are put forward on what is to be done to adopt this new concept in practice.  相似文献   
43.
地下水可持续开发:概念、原理与方法   总被引:2,自引:2,他引:0       下载免费PDF全文
水均衡是众所周知的原理,但是它的应用却常常引发很多争议.争议之一就是应用水均衡方程确定地下水的安全开采量和可持续开采量.对于地下水的天然补给量存在两种截然不同的误解:一种认为,如果地下水的开采量没有超过天然补给量,那么开采地下水就是安全的;另一种则认为,地下水的可持续开采量仅仅取决于地下水的捕获量,而与天然补给量无关.事实上,地下水的天然补给量和捕获量共同决定了地下水的安全开采量或可持续开采量.本文阐明了围绕水均衡的争议,并用水均衡方程剖析了安全开采量和可持续开采量的概念.文中对可持续开采量的定义进行了详细的解释,对实现地下水可持续开发的方法进行了总结.其中,地下水数值模拟模型和模拟-优化模型是确定地下水可持续开发方案的最有效的工具,文中也对这两个模型进行了简单的回顾.  相似文献   
44.
A simplified computational technique based on a refined global–local method is applied to the failure analysis of concrete structures. The technique distinguishes the scale of the structure, modelled with large size finite elements, from the scale at which material non‐linearity occurs due to progressive cracking and macro‐crack propagation. The finite element solution is split into two parts: a linear elastic analysis on a coarse mesh over the entire structure and a non‐linear analysis over a small part of the structure where a dense finite element grid is employed. In the non‐linear calculation, a non‐local damage model is implemented. These two computations are coupled with the help of an iterative scheme. The size and location of the region where a non‐linear analysis is performed, is adapted to follow the development of the damage zone. Numerical examples of mode I fracture of concrete specimens with straight and curved cracks are presented. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
45.
As the number of instruments applied in the area of energy and climate policy is rising, the issue of policy interaction needs to be explored further. This article analyses the interdependencies between the EU Emissions Trading Scheme (EU ETS) and the German feed-in tariffs (FITs) for renewable electricity in a quantitative manner using a bottom-up energy system model. Flexible modelling approaches are presented for both instruments, with which all impacts on the energy system can be evaluated endogenously. It is shown that national climate policy measures can have an effect on the supranational emissions trading system by increasing emission reduction in the German electricity sector by up to 79 MtCO2 in 2030. As a result, emission certificate prices decline by between 1.9 €/tCO2 and 6.1 €/tCO2 and the burden sharing between participating countries changes, but no additional emission reduction is achieved at the European level. This also implies, however, that the cost efficiency of such a cap-and-trade system is distorted, with additional costs of the FIT system of up to €320 billion compared with lower costs for ETS emission certificates of between €44 billion and €57 billion (cumulated over the period 2013–2020).

Policy relevance

In order to fulfil ambitious emission reduction targets a large variety of climate policy instruments are being implemented in Europe. While some, like the EU ETS, directly address CO2 emissions, others aim to promote specific low-carbon technologies. The quantitative analysis of the interactions between the EU ETS and the German FIT scheme for renewable sources in electricity generation presented in this article helps to understand the importance of such interaction effects. Even though justifications can be found for the implementation of both types of instrument, the impact of the widespread use of support mechanisms for renewable electricity in Europe needs to be taken into account when fixing the reduction targets for the EU ETS in order to ensure a credible long-term investment signal.  相似文献   
46.
写作教学长期以来是大学英语教学中的薄弱环节。教学指导思想和教学方式上的某些倾向是制约学生写作能力提高的一大障碍。分析了目前大学英语写作教学中存在的几大主要问题,并提出了一些建设性的改进方案。  相似文献   
47.
Towards understanding governance for sustainable urban water management   总被引:1,自引:0,他引:1  
Shifting from traditional, large, centralised infrastructure to alternative, distributed technologies is widely accepted as essential for enabling sustainable water management. Despite technical advances in sustainable urban water management over recent decades, the shift from traditional to more sustainable approaches remains slow. Current research on socio-institutional barriers suggests this poor implementation relates to a limited understanding of the different forms of governance needed to support alternative approaches, rather than the potential ineffectiveness of the technologies and practices. While some governance scholars express preferences for ideal hierarchical, market or network governance approaches, others suggest a hybrid of these approaches may be more appropriate for achieving sustainability. Currently, there is limited commentary about the potential characteristics of sustainable urban water governance. To extend the current scholarship, this paper systematically draws on the tacit knowledge of expert sustainability practitioners to identify potential governance characteristics of sustainable urban water management. In comparison with current urban water scholarship, which is supportive of a network governance approach at a conceptual level, the results strongly suggest that sustainability practitioners see the need for hybrid governance arrangements at a practical and operational level. These hybrid arrangements tended to comprise network and hierarchical approaches with market governance instruments. These insights from practitioners to help identify future research needs, focused on examining interaction among governance approaches at a variety of scales and locations.  相似文献   
48.
针对鄂托克旗国家基本气象站观测方式的改变,文章列举了几种特殊情况下的测报错情,并提出了处理方法。  相似文献   
49.
阻碍网络GIS性能的因素分为两大方面:硬件环境和软件环境。聚焦于软件环境,从通用网络GIS的三层体系架构上入手,分别在数据层、逻辑层和层间数据传输上描述了的一些可实施的优化途径及其技术原理,以综合应用来提高网络GIS的效率。  相似文献   
50.
Modification and channelization of streams and rivers have been conducted extensively throughout the world during the past century. Subsequently, much effort has been directed at re-creating the lost habitats and thereby improving living conditions for aquatic organisms. However, as restoration methods are plentiful, it is difficult to determine which one to use to get the anticipated result. The aim of this study was to compare two commonly used methods in small Danish streams to improve the physical condition: re-meandering and passive restoration through cease of maintenance. Our investigation included measurement of the physical conditions in 29 stream reaches covering four different groups: (1) re-meandered streams, (2) LDC streams (the least disturbed streams available), (3) passively restored streams (>10?years stop of maintenance) and (4) channelized and non-restored streams. The in-stream habitats were compared through analysis of the measured physical parameters and by applying a habitat model. We found that re-meandering is a more effective way of re-creating near-natural physical conditions in small streams compared to passive restoration. This is probably due to the limited energy in small streams which restricts re-shaping of the stream channel. However, based on habitat suitability modelling, the change to the physical condition did not translate into improved habitat suitability for young of the year brown trout highlighting the value of using several methods when evaluating restoration success.  相似文献   
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