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161.
162.
Environmental accounts bring together economic and environmental information in a common framework to measure the contribution of the environment to the economy and the impact of the economy on the environment. They enable governments to set priorities, monitor economic policies more precisely, enact more effective environmental regulations and resource management strategies, and design more efficient market instruments for environmental policies. This article uses examples from the regional environmental accounting programme in southern Africa to demonstrate the usefulness of environmental accounts to policy-making and natural resource management. The examples address the contribution of natural capital endowments (minerals and fisheries) to sustainable development in Botswana and Namibia; the economic importance of non-market forest goods and services in South Africa; and the socio-economic impact of current water allocation and pricing policies in Botswana, Namibia and South Africa. While there are many additional policy applications, these few provide a powerful argument for the use of environmental accounts in all countries.  相似文献   
163.
The natural vegetation growing along a wastewater channel was subjected to analyze the uptake of Cadmium (Cd) and Zinc (Zn) and their subsequent accumulation in aboveground and underground plant parts. Species which were mycorrhizal and growing in soils receiving industrially contaminated wastewater were collected along with their rhizospheric soil samples. The nearby uncontaminated control (reference) area was also subjected to sampling on similar pattern for comparison. Both Cd and Zn concentrations were significantly higher in soils of the study area as compared to the reference site. Five plant species i.e. Desmostachya bipinnata, Dichanthium annulatum, Malvastrum coromandelianum, Saccharum bengalense, and Trifolium alexandrinum were analyzed for metal uptake. The maximum phytoaccumulation of Cd was observed in Desmostachya bipinnata (20.41 μg g−1) and Dichanthium annulatum (15.22 μg g−1) for shoot and root tissues, respectively. However, Malvastrum coromandelianum revealed maximum Zn accumulation for both the shoot and the root tissues (134 and 140 μg g−1, respectively). The examination of cleared and stained roots of the plants from both the areas studied revealed that all of them were colonized to a lesser or a greater degree by arbuscular mycorrhizal (AM) fungi. The Cd hyperaccumulating grasses i.e. Desmostachya bipinnata and Dichanthium annulatum, from study area had smaller root:shoot (R/S) ratio as compared to those growing on reference area indicating a negative pressure of soil metal contamination. The lower R/S ratio in the mycorrhizal roots observed was probably due to increased AM infection and its mediatory role in soil plant transfer of heavy metals. Furthermore, comparatively lower soil pH values in the study areas may have played a key role in making the overall phytoavailability of both the metals. Consequently variations in Cd and Zn tissue concentration among species were observed that also indicate the phytoaccumulation potential of the native species.  相似文献   
164.
Protected areas (PAs) represent a key global strategy in biodiversity conservation. In tropical developing countries, the management of PAs is a great challenge as many contain resources on which local communities rely. Collection and trading of non-timber forest products (NTFPs) is a well-established forest-based livelihood strategy, which has been promoted as a potential means for enhanced conservation and improved rural livelihoods in recent years, even though the sustainability or ecological implications have rarely been tested. We conducted an exploratory survey to understand the role and stakeholder views on conservation prospects and perceived ecological feasibility of NTFPs and harvesting schemes in a northeastern PA of Bangladesh, namely the Satchari National Park. Households (n?=?101) were interviewed from three different forest dependency categories, adopting a stratified random sampling approach and using a semi-structured questionnaire. The study identified 13 locally important NTFPs, with five being critically important to supporting local livelihoods. Our study suggests that collection, processing and trading in NTFPs constitutes the primary occupation for about 18% of local inhabitants and account for an estimated 19% of their cash annual income. The household consensus on issues relating to NTFPs and their prospective role in conservation was surprisingly high, with 48% of respondents believing that promotion of NTFPs in the PA could have positive conservation value. The majority (71%) of households also had some understanding of the ecological implications of NTFP harvesting, sustainability (53%) and possible management and monitoring regimes (100%). With little known about their real application in the field, our study suggests further investigations are required to understand the ecological compatibility of traditional NTFP harvesting patterns and management.  相似文献   
165.
Both leader–member exchange (LMX) and team–member exchange (TMX) measure the quality of reciprocal exchange among employees in the workplace. Although LMX focuses on supervisor–subordinate relationships while TMX examines the relationships among team members, both have theory‐based and empirically proven relations with workplace outcomes such as job performance, organizational commitment, job satisfaction, and turnover intentions. However, it is not yet known which has more of an impact on such workplace outcomes—specifically, it is not clear if an employee's time is best spent developing vertical relationships among supervisors and subordinates (LMX) or on the horizontal relationships among team members (TMX). Accordingly, this meta‐analysis explores the incremental validity and relative importance of these two social exchange‐based constructs. The theoretical logic underlying LMX and TMX is clarified, and the parameter estimates between LMX, TMX, and work outcomes are reported. Results demonstrate that TMX shows incremental validity above and beyond LMX for some outcomes (organizational commitment and job satisfaction), but not others (job performance and turnover intentions). Also, LMX shows greater relative importance across all four outcomes. In sum, the clarification of the theoretical and empirical landscape lays a foundation for recommendations for future research. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
166.
湘西古丈红石林国家地质公园出露着奥陶系牯牛潭组红色石灰岩地层,含角石化石,被认为是海相红层.野外观察地层红色深浅与其层理/层次变化关系判断为近于同期形成,属原生色.水生化石存在红层中,前者反映水下缺氧条件,而红层指示着氧化环境,两种指示尖锐对立,意味着可能至少一方存在认识偏差.采样分析结果表明,赤铁矿和针铁矿是其中可以...  相似文献   
167.

Purpose

Combinatorial bio/chemical approach was applied to investigate dioxin-like contamination of soil and sediment at the petrochemical and organochlorine plant in Pancevo, Serbia, after the destruction of manufacturing facilities that occurred in the spring of 1999 and subsequent remediation actions.

Materials and methods

Soil samples were analyzed for indicator polychlorinated biphenyls (PCBs) by gas chromatography/electron capture detection (GC/ECD). Prioritized soil sample and sediment samples from the waste water channel were analyzed for polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) by high-resolution gas chromatography/high-resolution mass spectrometry (HRGC/HRMS). Microethoxyresorufin o-deethylase (Micro-EROD) and H4IIE?Cluciferase bioassays were used for monitoring of dioxin-like compounds (DLC) and for better characterization of dioxin-like activity of soil samples.

Results

Bioanalytical results indicated high dioxin-like activity in one localized soil sample, while the chemical analysis confirmed the presence of large quantities of DLC: 3.0?×?105 ng/g d.w. of seven-key PCBs, 8.2 ng/g d.w. of PCDD/Fs, and 3.0?×?105 ng/g d.w. of planar and mono-ortho PCBs. In the sediment, contaminant concentrations were in the range 2?C8 ng/g d.w. of PCDD/Fs and 9?C20 ng/g d.w. of PCBs.

Conclusions

This study demonstrates the utility of combined application of bioassays and instrumental analysis, especially for developing and transition country which do not have capacity of the expensive instrumental analysis. The results indicate the high contamination of soil in the area of petrochemical plant, and PCDD/Fs contamination of the sediment from the waste water channel originating from the ethylene dichloride production.  相似文献   
168.
This study investigates the presence of environmental kuznets curve (EKC) for green house gases (GHG) measured by CO2 emission in Malaysia for the period 1970 to 2011. The study also examines the potential of the renewable source of energy to contain GHG. The long-run significant positive coefficient of GDP indicates that the GHG are increasing with economic growth while the insignificant coefficient on GDP square rejects the EKC transition. These results indicate a high GDP level for the EKC turning point for Malaysia. Therefore, it can be stated that only economic growth cannot reverse the environmental degradation in Malaysia. The government should have to come up with some policy measures to achieve CO2 emission reduction targets that Malaysia has pledged to achieve in Paris Submit (2015). The renewable energy production is found to have significant negative effect on CO2 emission. So government should focus on the renewable source of energy production and should frame a special policy for renewable energy production.  相似文献   
169.
170.
Flood forecasts and warnings are intended to reduce flood‐related property damages and loss of human life. Considerable research has improved flood forecasting accuracy (e.g., more accurate prediction of the occurrence of flood events) and lead time. However, the delivery of improved forecast information alone is not necessarily sufficient to reduce flood damage and loss of life, as people have varying responses and reactions to flood warnings. This study develops an agent‐based modeling framework that evaluates the impacts of heterogeneity in human behaviors (i.e., variation in behaviors in response to flood warnings), as well as residential density, on the benefits of flood warnings. The framework is coupled with a traffic model to simulate evacuation processes within a road network under various flood warning scenarios. The results show the marginal benefit associated with providing better flood warnings is significantly constrained if people behave in a more risk‐tolerant manner, especially in high‐density residential areas. The results also show significant impacts of human behavioral heterogeneity on the benefits of flood warnings, and thus stress the importance of considering human behavioral heterogeneity in simulating flood warning‐response systems. Further study is suggested to more accurately model human responses and behavioral heterogeneity, as well as to include more attributes of residential areas to estimate and improve the benefits of flood warnings.  相似文献   
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