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701.

The United Nations Climate Conference 25, held in December 2019, reached a significant agreement against implementing the Paris agreement come 2020. Bound by the contract, 189 countries who are party to the deal agreed to constrain worldwide temperature to ascend to 1.5° Celsius. To this end, the present study attempts to investigate the readiness of selected countries in the European Union to implement the agreement, which will better the quality of the global environment. In line with this, this study appraises the connection between economic growth, renewable and non-renewable energy consumption, on emissions in 11 countries in the European Union from 1990 to 2016. The study utilises the Pooled Mean Group-Auto Regressive Distributed Lag (PMG-ARDL) model estimator and Dumitrescu and Hurlin Panel Causality analysis to analyse the long-run and short-run impact and direction of causality among these factors, respectively. The long-run study's empirical results show a U-shaped Environmental Kuznets Curve (EKC) and a negative connection between renewable energy use and emissions in the EU-11 countries. In the short-run, non-renewable energy use worsens CO2 emissions while renewable energy use leads to a fall in emissions. Similarly, causality tests show a feedback mechanism between emissions and renewable energy use and between non-renewable energy and renewable use. Also, there is unidirectional causality from income to CO2 emissions, non-renewable energy use to CO2 emissions. The investigation recommends an expanded proportion of renewable energy sources in the EU countries’ energy mix to cut down on emissions.

  相似文献   
702.
Environmental Science and Pollution Research - Considering the prevailing wave of global warming and other environmental challenges, which can be attributed to increasing environmental pollution as...  相似文献   
703.
Environmental Science and Pollution Research - In recent times, the persistent global environmental challenges have paved the way for the underpinning of climate change within the perspective of...  相似文献   
704.
The total elemental concentrations and proximate chemical composition of five different tree nuts, almond (Prunus dulcus), Brazil (Bertholletia excelsa), pecan (Carya pecan), macadamia (Macadamia integrifolia) and walnut (Juglans nigra) that are consumed in South African households were investigated. In addition, six physicochemical properties of the extracted nut oils, namely acid value, iodine value, saponification value, refractive index, density and specific gravity were evaluated. A high concentration of Se (36.1 +/- 0.4 microg g(- 1)) was found in the Brazil nuts only. With maximum and minimum limits being set by the almond and pecan nut samples, Cr ranging from 0.94 +/- 0.14-2.02 +/- 0.07 microg g(- 1) was detected in the nut samples. Generally, the order of the concentrations of the elements in all the nut samples is found to be Mg > Ca > Fe > Cu > Cr > As > Se. The concentrations of Mn and Zn showed greater variation amongst the different types of nuts. The extracted oils showed low acid values and high saponification values with the macadamia nut sample having the highest oil content (76.0 +/- 0.5 g per 100 g of sample), the lowest acid value (0.42 +/- 0.01 mg KOH per g of oil) and highest saponification value (193.7 +/- 2.4 mg KOH per g of oil). The present findings are useful in calculating the Dietary Reference Intakes of these nutrients.  相似文献   
705.
Many threats to biodiversity can be predicted and are well mapped but others are uncertain in their extent, impact on biodiversity, and ability for conservation efforts to address, making them more difficult to account for in spatial conservation planning efforts, and as a result, they are often ignored. Here, we use a spatial prioritisation analysis to evaluate the consequences of considering only relatively well-mapped threats to biodiversity and compare this with planning scenarios that also account for more uncertain threats (in this case mining and armed conflict) under different management strategies. We evaluate three management strategies to address these more uncertain threats: 1. to ignore them; 2. avoid them; or 3. specifically target actions towards them, first individually and then simultaneously to assess the impact of their inclusion in spatial prioritisations. We apply our approach to the eastern Democratic Republic of the Congo (DRC) and identify priority areas for conserving biodiversity and carbon sequestration services. We found that a strategy that avoids addressing threats of mining and armed conflict more often misses important opportunities for biodiversity conservation, compared to a strategy that targets action towards areas under threat (assuming a biodiversity benefit is possible). We found that considering mining and armed conflict threats to biodiversity independently rather than simultaneously results in 13 800–14 800 km2 and 15 700–25 100 km2 of potential missed conservation opportunities when undertaking threat-avoiding and threat-targeting management strategies, respectively. Our analysis emphasises the importance of considering all threats that can be mapped in spatial conservation prioritisation.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-022-01724-0.  相似文献   
706.
Designing the Ark: Setting Priorities for Captive Breeding   总被引:2,自引:0,他引:2  
Zoos can help conserve only a small minority of the species threatened with extinction. Clear and rational criteria for identifying which threatened taxa zoos should focus on are therefore essential. Current priorities for ex situ conservation stress the importance of large vertebrates. We show that this hampers the efficient use of resources because such species are less likely to breed well in captivity than smaller-bodied taxa and, despite longer generation lengths, are more costly to maintain in long-term breeding programs. Moreover, although reintroduction to the wild frees zoo space for other species and is the ultimate aim of captive breeding, zoos show no tendency to target species for which continued habitat availability makes reintroduction a realistic prospect. We suggest that zoos adopt selection criteria that reflect the economic and biological realities of captive breeding and reintroduction if they are to maximize their contribution to species conservation, and we present data on the preferences of zoo visitors indicating that doing so need not adversely affect zoo attendance.  相似文献   
707.
708.
Nucleation of polylactide and polypropylene using novel renewable resource biobased carbon nanospheres (CNS) is investigated using differential scanning calorimetry and polarized optical microscopy. Isothermal studies near the optimal crystallization temperature demonstrate at least a five-fold increase in crystallization rate in PP but only a 1.4 times faster crystallization in PLA. Non-isothermal studies reveal an asymptotic relationship of the maximum crystallization temperature with increasing CNS weight loading in PP and no relationship in PLA. Microscopy indicates some aggregation in the solution blended samples and that average spherulite size is reduced 10-fold due to faster nucleation in the composites as compared to the neat polymer. The fractional crystallinity achieved during non-isothermal crystallization increases by about 7% with addition of a small amount of CNS and decreases with weight loading higher than 1%. The crystallization rates obtained in polypropylene are competitive with widely used mineral talc nucleating agents.  相似文献   
709.
Out study deals with the demand for water and alternative agricultural production and land use patterns under varying prices for both surface and ground water. We derive irrigation water demands for both the United States and regions of it. Not only is a different amount of water used at each set of water prices but also a different mix of crops, livestock, and production technology develops among the different regions. Under the highest set of prices used, more than fourteen million acres are converted into dryland farming. Total irrigated water use decreases by more than 25 million acre-feet. Irrigated crop yields are reduced and cropping patterns shift away from irrigation. Commodity shadow prices increase as much as 15 percent under high prices for both surface and ground water. A redistribution of farm income occurs between irrigated and dryland regions.  相似文献   
710.
Regional Environmental Change - Paleoecological and paleosocial synthesis, meaning the examination of data and patterns derived from past social and ecological systems, provides an important...  相似文献   
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