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1.
Background The quantification of resource depletion in Life Cycle Assessment has been the topic of much debate; to date no definitive approach for quantifying effects in this impact category has been developed. In this paper we argue that the main reason for this extensive debate is because all methods for quantifying resource depletion impacts have focussed on resource extraction. - Aim and Scope. To further the state of the debate we present a general framework for assessing the impacts of resource use across the entire suite of biotic and abiotic resources. The main aim of this framework is to define the necessary and sufficient set of information required to quantify the effects of resources use. Method logy. Our method is based on a generic concept of the quality state of resource inputs and outputs to and from a production system. Using this approach we show that it is not the extraction of materials which is of concern, but rather the dissipative use and disposal of materials. Using this as a point of departure we develop and define two key variables for use in the modelling of impacts of resource use, namely the ultimate quality limit, which is related to the functionality of the material, and backup technology. Existing methodologies for determining the effects of resource depletion are discussed in the context of this framework. Results We demonstrate the ability of the general framework to describe impacts related to all resource categories: metallic and non-metallic minerals, energy minerals, water, soil, and biotic resources (wild or domesticated plants and animals). Recommendation focus on suggestions for a functionality measure for each of these categories; and how best the two modelling variables derived can be determined.  相似文献   

2.
水足迹研究进展   总被引:19,自引:6,他引:19  
马晶  彭建 《生态学报》2013,33(18):5458-5466
水为生命之源,水资源的合理分配与科学管理是区域可持续发展与流域综合管理的核心环节;水足迹作为一种全面核算人类活动对水资源真实占用的综合指标,将人类消费终端与水资源利用密切关联,为维护流域水资源安全、提高区域水资源利用效率提供了重要的科学依据,已成为当前国际水资源管理的前沿研究领域。在明确水足迹及水资源生态足迹相关概念的基础上,对比分析了水足迹与生态足迹、水资源生态足迹模型的异同,明晰了过程、产品及区域等不同研究对象的水足迹核算方法,系统梳理了产品和区域水足迹评价、基于水足迹的区域水资源安全研究、区域水足迹可持续性分析等水足迹主要研究内容的近今进展,并展望了进一步的重点研究方向,即水足迹综合研究、水足迹评价不确定性分析、水足迹与物质流核算的关联研究,以及基于足迹整合的可持续发展多维测度等。  相似文献   

3.
Overyielding among plant functional groups in a long-term experiment   总被引:12,自引:0,他引:12  
A recent debate among ecologists has focused on mechanisms by which species diversity might affect net primary productivity. Communities with more species could use a greater variety of resource capture characteristics, leading to greater use of limiting resources (complementarity) and therefore greater productivity (overyielding). Recent experiments, however, have shown a variety of relationships between diversity and productivity. In an experiment on serpentine grassland communities spanning 8 years, we found that overyielding increased several years after plot establishment. Overyielding varied greatly depending on the functional characteristics of the species involved and the biotic and abiotic environment (particularly water availability). While functional differences among species led to strong complementarity and facilitation, these effects were not sufficient to cause significant transgressive overyielding or consistent increases in productivity with increased plant diversity. These results suggest that greater absolute production with greater diversity may be restricted to particular species combinations or environmental conditions.  相似文献   

4.
Hydrobiologia - The invasive species Nile tilapia is a filter-feeding omnivorous fish that can have a negative effect on zooplankton and phytoplankton resources. However, the strength of its...  相似文献   

5.
Frau  Diego 《Hydrobiologia》2022,849(4):833-860
Hydrobiologia - The role of grazing as a controlling factor of phytoplankton has an extensive debate in the literature. In this article, five mechanisms that have been explored as potential...  相似文献   

6.
The virtual water concept has received significant attention through manifesting the role of human activities such as consumption and international trade on water resources. However, few studies have focused on how the interactions of local supply chain exert impact on local water resources associated with virtual water flows. In this study, we introduce an indicator which is attached to the virtual water concept, termed the “internal water use of products” (IWUP), to examine the direct and indirect water use from local water supply for goods and services in Beijing for the years 1997, 2000, 2002, 2007, and 2010. This indicator links the pressure on local water resources to the final products with sectoral details, highlighting the importance of economic analysis in local water resource management. A structural decomposition analysis revealed that the increase in economic water productivity would have caused Beijing's IWUP to decrease by 196% from 1997 to 2010, if other determining factors remained constant. Such great efficiency improvements have allowed Beijing to fulfill its objectives of economic growth, whilst in the meantime reducing the water used in production. However, we also found that production structure adjustment would increase the IWUP, mainly due to a shift from agricultural and industrial sectors to service sectors.  相似文献   

7.
This article presents the trends of two indicators measuring fossil resource consumption in the United Kingdom (UK). First, a domestic material consumption (DMC) indicator for fossil resources (DMCfossil) in the mass unit million tonnes is calculated. DMCfossil shows that between 1970 and 2000 UK fossil resource consumption decreased by 10%, which suggests absolute dematerialization for this resource. Investigation into the mix of fossil resources during this period highlighted the shift from the heavy fossil resource coal to the lighter, more energy‐dense natural gas, which resulted in decreased mass of resource required. Second, an alternative indicator, resource consumption by a nation (RCN) for fossil resources (RCNfossil) was calculated, which includes the indirect fossil resources attributable to traded goods and is measured in million tonnes of oil equivalent. RCNfossil shows that between 1970 and 2000 United Kingdom's fossil resource consumption increased by 14%, which emphasizes that even though there has been a decrease in the mass of fossil resources demanded, it has been accompanied by an increase in the volume of resource consumed. Additionally, deconstruction of RCNfossil shows that indirectly used resources attributable to exports and imports for the United Kingdom are significant. RCNfossil indicates that on the basis of past trends, fossil resources attributable to UK imports will overtake fossil resources attributable to its exports, which will make it dependent on imported resources. We conclude that further debate on appropriate aggregate and complementary indicators is needed.  相似文献   

8.
路杨  刘秀位  张喜英 《生态学杂志》2015,26(10):3207-3214
水是人类生产生活的重要资源,科学合理地评价人类活动对水资源的影响是实现水资源可持续利用的重要保障.水足迹概念的提出创新性地将人类活动消耗的水资源区分为绿水、蓝水和灰水,拓展了水资源可持续利用的评价思路.基于虚拟水(VW)的水足迹理论和基于生命周期(LCA)的水足迹理论将水质与水量的概念相结合,成为了农业水资源管理研究的热点内容.基于VW的水足迹理论主要包括绿水足迹、蓝水足迹和灰水足迹的计算,以及水环境可持续性评价,而基于LCA的水足迹理论体现了水资源的消耗和污染及其对环境造成的综合影响.本文详细介绍了这两种水足迹理论的计算方法与环境可持续评价的研究进展,对比分析两种水足迹理论在描述农产品生产用水及其环境影响方面的差异性,并对其研究前景进行了展望.  相似文献   

9.
The articles in this volume of Hydrobiologia commemorate the 40th anniversary of the Mississippi River Research Consortium by synthesizing research and monitoring conducted on the river over the past 40 years. This article briefly describes the recent history of development (since 1866) of the river and the programs that currently support monitoring, research, and rehabilitation of the river. These programs have generated much of the information reported in the articles, which cover hydrology and geomorphology, contaminants, nutrients, plants, reptiles and amphibians, food webs, and concepts of river ecology. The Upper Mississippi River is still responding to changes that occurred 70 or more years ago (construction of navigation dams, leveeing of the floodplains, and intensification of agriculture in the catchment) and to new stressors (climate change, invasive species, hormone-disrupting chemicals). Nevertheless, the river continues to attract 12 million visitors per year along the scenic Great River Road, hosts 36% of all the migrating ducks in the contiguous United States, and is home to 129 native species of freshwater fishes. The biological productivity and diversity of the river are likely to be maintained and even enhanced if the following occur: (1) planned rehabilitation efforts are coupled with hypothesis testing (adaptive environmental assessment and management); (2) sampling is extended beyond the six river reaches that are currently monitored intensively; (3) new sensor networks are developed and deployed; (4) water quality is protected by better controls on nonpoint sources and better testing of new chemicals before they are widely introduced; and (5) ways are found to engage multidisciplinary teams of academic scientists around the world, as well as agency scientists and managers, in cooperative efforts to better understand and manage large, complex, dynamic floodplain–river ecosystems.  相似文献   

10.
The water footprint (WF) has been developed within the water resources research community as a volumetric measure of freshwater appropriation. The concept is used to assess water use along supply chains, sustainability of water use within river basins, efficiency of water use, equitability of water allocation and dependency on water in the supply chain. With the purpose of integrating the WF in life cycle assessment of products, LCA scholars have proposed to weight the original volumetric WF by the water scarcity in the catchment where the WF is located, thus obtaining a water-scarcity weighted WF that reflects the potential local environmental impact of water consumption. This paper provides an elaborate critique on this proposal. The main points are: (1) counting litres of water use differently based on the level of local water scarcity obscures the actual debate about water scarcity, which is about allocating water resources to competing uses and depletion at a global scale; (2) the neglect of green water consumption ignores the fact that green water is scarce as well; (3) since water scarcity in a catchment increases with growing overall water consumption in the catchment, multiplication of the consumptive water use of a specific process or activity with water scarcity implies that the resultant weighted WF of a process or activity will be affected by the WFs of other processes or activities, which cannot be the purpose of an environmental performance indicator; (4) the LCA treatment of the WF is inconsistent with how other environmental footprints are defined; and (5) the Water Stress Index, the most cited water scarcity metric in the LCA community, lacks meaningful physical interpretation. It is proposed to incorporate the topic of freshwater scarcity in LCA as a “natural resource depletion” category, considering depletion from a global perspective. Since global freshwater demand is growing while global freshwater availability is limited, it is key to measure the comparative claim of different products on the globe's limited accessible and usable freshwater flows.  相似文献   

11.
Fryer  Geoffrey 《Hydrobiologia》2004,519(1-3):167-183
Hydrobiologia - Rates of evolutionary change in Lake Victoria continue to stimulate debate. If, as some have claimed, the present fauna is &;lt;15 000 years old, speciation must have...  相似文献   

12.
Invasive species may outperform native species by acquiring more resources or by efficiently using limited resources. Studies comparing leaf traits as a metric of carbon capture strategies in native and invasive species have come to different conclusions. Some studies suggest that invasive species are better at acquiring resources, but that native and invasive species use resources similarly. Other studies have found that native and invasive species differ in resource use efficiency, which implies different biochemical or physiological mechanisms of carbon capture. To resolve this debate, we examined relationships among four leaf traits (photosynthetic rate, specific leaf area, foliar nitrogen, foliar phosphorus) in co-occurring native and invasive species from eight plant communities across five Mediterranean-climate ecosystems. We performed standardized major axis regression for all trait combinations within and across sites, testing for slope homogeneity and shifts in elevation (y-intercept) or along a common slope between species groups. Across the global dataset, native and invasive species had similar carbon capture strategies (i.e., similar slopes), with invasive species occupying a position of greater resource acquisition. However, these patterns did not hold when regions were analyzed individually. Regional differences may be driven by differences in life form between native and invasive species, and variation in soil resource availability among regions. Our context-dependent results reveal not only that management of invasive species will differ across regions but also that global comparisons of invasive and native species can be misleading.  相似文献   

13.
SOS!濒临极限的生物多样性   总被引:6,自引:0,他引:6  
本文论述了生物多样性的价值、多样性丧失的严重性和后果,以及多样性保护与持续利用的对策。文中强调指出,生物界中的每片基因,每一个物种,每一类生态系统对人类的持久生存都是无价之宝,任何多样性的丧失都是不可逆、不可再生的,因而对人类的损失是难以估量的。然而目前由于人类剧烈的活动干扰如滥砍滥伐、滥捕滥猎、环境污染、火灾、垦荒等,生物多样性丧失的速率怵目惊心!若不赶快行动起来,人类赖以生存的生物多样性将所剩无几,人类生存的危机也将难以避免。从保护与利用及其协同发展出发,本文呼吁要大力开展生物多样性的研究和开发工作,目的一方面在于进一步加强生物多样性的基础调查和研究工作,另一方面在于使生物多样性资源更好地为人类造福。为减缓目前生物多样性所承受的压力及促进其恢复,本文建议对完全依赖野生生物资源的传统产业征收“资源更新税”;而对开发和利用生物多样性资源,不仅不影响野生资源,而且能替代它,或减缓其压力,或促进其恢复的高新技术产业,在税收上给予特别优惠。  相似文献   

14.
Recent modification of the South African Water Law spells out fundamental changes for the way the country's water resources will be managed in the future. One of the most significant mandates is the establishment of Catchment Management Agencies (CMAs) and the delegation of water resource management responsibilities to these institutions. Their function will focus on the overall management of water resources on a catchment basis. Within the context of the new legal framework, there is a great need for support to CMAs, particularly in providing them with procedures for the optimal management of water resources in order to ensure a balance between sustainable use and protection of the resource. This paper describes a research project that aims to develop a protocol for the integrated management of the biophysical component of a catchment, with particular focus on river systems. This protocol will be a management tool for Catchment Management Agencies in support of more integrated and sustainable water resource management.

South Africa's Sabie-Sand catchment was selected as a case study area for several reasons. This catchment has a large number of current and historic water resource related initiatives, such as the Working for Water Programme (alien plant clearing), the River Health Programme (river quality assessment) and The Kruger National Park Rivers Research Programme (a river management programme). In addition the diversity of stakeholders and land-use issues in the catchment and the extensive collection of available information relating to water use and protection for this catchment makes the Sabie-Sand a rich learning ground.

This project aims to use information from the Sabie catchment to produce and implement a protocol which will combine and integrate the knowledge of water resource management from diverse but related fields in order to enhance catchment-based integrated water resource management. It also aims to extract and document lessons from current research initiatives, to assess the usefulness and relevance of their products for CMAs and to identify gaps in the research framework that need to be addressed in order to meet the water resource management needs of CMAs. This paper reports on the project development during its first phase, describes the next steps in the research process and provides a conceptual framework of how the research team envisages the practical implementation of the protocol.  相似文献   

15.
Genetics education is essential for preparing the public to engage in an informed debate about the future of genetics research and how its applications affect human health and the environment. This article provides an overview of genetics education resources that are available online, and is relevant to students in secondary education, health professionals, geneticists and the public. It also describes an integrated approach to teaching genetics, emphasizes the need for continuing teacher education, and encourages the involvement of geneticists and health professionals in providing a teaching resource.  相似文献   

16.
矿泉水是地下水从含水层中经长期与岩石相互作用形成、富含有益于人体的丰富矿物质和微量元素的一类顶级饮用地下水资源.在水资源污染严重而且生态环境不断恶化的今天,基于新的科技认知手段重新认识矿泉水的生态和健康效应,具有重要意义.黑龙江省五大连池风景区拥有着五大连池旅游疗养业赖以生存和发展的优质矿泉水资源,并且被应用于医疗和保健方面已有百余年历史,但是面临着资源量减少、环境污染等问题的威胁.本文主要针对五大连池矿泉水的形成过程、分布规律、水化学和微生物特征及其健康效应等进行综合评述,侧重其微生物特征的研究进展,提出了未来五大连池矿泉的研究展望.为了更好地保护和利用五大连池矿泉水,建议五大连池周边农场发展绿色生态农业,减少化肥的施用;在开发旅游和疗养资源的同时,要严格建立污染风险的评估和管控体系,减少“新型”环境污染物对地质生态环境的可能污染.  相似文献   

17.
The survival of the NHS lies largely in the hands of government, and this article suggests steps that it should take to deal with pressures on the NHS in terms of funding, managing efficiency, and demands. Changes to the system of funding may be unfeasible, but management could be improved by research to allow greater understanding of the local effects of national policies. Alternatively health authorities could be given more freedom to manage funds, although this would have to be accompanied by stiff sanctions for those who failed. Demand could be contained by strengthening policies to ensure that new technologies are cost effective. The government could try to reduce demands arising from increased expectations by encouraging informed public debate about priorities and influencing the availability of private health care. All these efforts should be guided by the values underpinning the NHS, which should be debated and decided collectively and confirmed in a new charter for NHS''s 50th anniversary in 1998.  相似文献   

18.
The year 2012 marks the 25th anniversary of the donation of ivermectin to fight onchocerciasis and the projected date for elimination of transmission of the disease in the Americas. This review looks at the history of onchocerciasis, from its discovery through to 2025, by which time it is projected that the disease will have been eliminated as a public health problem, except in a handful of sub-Saharan countries, where it should be well on the way towards elimination.  相似文献   

19.
Anthropogenic modification of habitats may reduce the resources available for native species, leading to population declines and extinction. These same habitats often have the highest richness of non-native species. This pattern may be explained if recently human-modified habitats provide novel resources that are more accessible to non-native species than native species. Using non-native birds in the Iberian Peninsula as a case study, we conduct a large-scale study to investigate whether non-native species are positively associated with human modified habitats, and to investigate whether this positive association may be driven by the presence of resources that are not fully exploited by native species. We do this by comparing the functional diversity and resource use of native and non-native bird communities in a recently human-modified habitat (rice fields) and in more traditional habitats in the Iberian Peninsula. The functional diversity of native bird communities was lower in rice fields, but non-native birds were positively associated with rice fields and plugged this gap. Differences in resource use between native and non-native species allowed non-native species to exploit resources that were plentiful in rice fields, supporting the role of underexploited resources in driving the positive association of non-native birds with rice fields. Our results provide a potential mechanism explaining the positive association of non-native species with anthropogenic habitats, and further work is needed to test if this applies more generally.  相似文献   

20.
Resource competition in heterogeneous environments is still an unresolved problem of theoretical ecology. In this article, I analyze competition between two phytoplankton species in a deep water column, where the distributions of main resources (light and a limiting nutrient) have opposing gradients and co-limitation by both resources causes a deep biomass maximum. Assuming that the species have a trade-off in resource requirements and the water column is weakly mixed, I apply the invasion threshold analysis (Ryabov and Blasius, Ecol Lett 14:220–228, 2011) to determine relations between environmental conditions and phytoplankton composition. Although species deplete resources in the interior of the water column, the resource levels at the bottom and surface remain high. As a result, the slope of resources gradients becomes a new crucial factor which, rather than the local resource values, determines the outcome of competition. The value of resource gradients nonlinearly depend on the density of consumers. This leads to complex relationships between environmental parameters and species composition. In particular, it is shown that an increase of both the incident light intensity or bottom nutrient concentrations favors the best light competitors, while an increase of the turbulent mixing or background turbidity favors the best nutrient competitors. These results might be important for prediction of species composition in deep ocean.  相似文献   

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