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591.
节能环保产业作为战略性新兴产业的七大重点领域之一,新形势下发展具备有利条件,特别是十二五以来我国环保产业得到了飞速发展,但是由于体制机制、技术、市场等多方面原因环保产业发展也面临诸多挑战和障碍。日本与韩国,环保产业已进入技术成熟期,逐渐成为本国国民经济的支柱产业和世界环保市场的主力,借鉴日韩环保产业的发展经验,提出中国推动环保产业发展的对策建议。 相似文献
592.
Some believe that provision of private property rights in wildlife on private land provides a powerful economic incentive for nature conservation because it enables property owners to market such wildlife or its attributes. If such marketing is profitable, private landholders will conserve the wildlife concerned and its required habitat. But land is not always most profitably used for exploitation of wildlife, and many economic values of wildlife (such as non-use economic values) cannot be marketed. The mobility of some wildlife adds to the limitations of the private-property approach. While some species may be conserved by this approach, it is suboptimal as a single policy approach to nature conservation. Nevertheless, it is being experimented with, in the Northern Territory of Australia where landholders had a possibility of harvesting on their properties a quota of eggs and chicks of red-tailed black cockatoos for commercial sale. This scheme was expected to provide an incentive to private landholders to retain hollow trees essential for the nesting of these birds but failed. This case and others are analysed. Despite private-property failures, the long-term survival of some wildlife species depends on their ability to use private lands without severe harassment, either for their migration or to supplement their available resources, for example, the Asian elephant. Nature conservation on private land is often a useful, if not essential, supplement to conservation on public lands. Community and public incentives for such conservation are outlined. 相似文献
593.
594.
A preliminary investigation on the occurrence and distribution of antibiotic resistance genes in the Beijiang River, South China 总被引:6,自引:0,他引:6
The occurrence of antibiotic resistance genes (ARGs) was investigated and quantified in 20 water samples collected in the Beijiang River, South China. Sulfonamide- and tetracycline-resistant bacteria were present in 17 and 14 of the collected 20 samples. For sulfonamide ARGs, sulI and sulII were frequently observed in the Beijiang River. The levels of sulI were higher than sulII (p < 0.05), with the mean values of (1.41 ± 1.12) × 10-2 and (1.58 ± 1.71) × 10-3 copies/16S rDNA, respectively. For tetracycline ARGs, tetG had the highest frequency, 100%, followed by tetA (85%), tetO (85%), tetC (70%), tetX (60%), tetM (40%) and tetQ (20%), while tetE and tetS were not detected in all the samples from the Beijiang River. On the other hand, tetC had the highest concentration, ranging from 8.30 × 10-2 to 13.20 copies/16S rDNA. The poor correlation between ARGs and antibiotic concentrations revealed that the self-amplification and persistence of ARGs were the reasons that made ARGs exist in the water environment even though the antibiotic selecting pressure was absent. Because so few field measurements have been conducted for investigating the levels of ARGs in rivers in South China, this study provides an important insight on better understanding the occurrence and spread of ARGs in such an ecosystem. 相似文献
595.
以长链烷基苯(LABs)作为生活污水排放的示踪剂,测定了珠江三角洲主要河流及邻近南海北部海域表层沉积物中LABs浓度.结果表明,珠江、东江、西江、伶仃洋及南海北部海域样品中LABs的浓度分别为58.5~2332.1,96.9~565.8,20.5~57.0,5.8~25.8,2.5~23.1ng/g.LABs的I/E值表明,研究区域内生活污水基本上未处理或处理效率低下.对LABs与多环芳烃及多溴联苯醚的相关性分析表明,城市污水的排放是该区域内这些有机污染物的重要来源之一. 相似文献
596.
近20 a南海赤潮的时空分布特征及原因分析 总被引:5,自引:1,他引:4
收集整理了自1980~2004年的南海历次赤潮事件,并对这些赤潮事件在时间和空间的分布特征以及赤潮持续时间长度的变化特征进行了分析;探讨了形成南海赤潮时空分布特征和持续时间长度变化的可能原因.文章认为:赤潮在年度和月份分布不均的原因主要是气候差异以及各月份水文气象要素的主要演变特征不同;赤潮持续时间延长的原因与南海区气候转暖和广东近岸海域水质变差有关.研究发现赤潮事件的月份分布和赤潮持续时间长度存在历史性变异,有关现象值得管理部门和学术界的注意,而其中原因更有待进一步研究. 相似文献
597.
Laura K. Blamey Éva E. Plagányi Trevor Hutton Roy A. Deng Judy Upston Annie Jarrett 《Conservation biology》2022,36(3):e13864
Short-lived, fast-growing species that contribute greatly to global capture fisheries are sensitive to fluctuations in the environment. Uncertainties in exact stock–environment relationships have meant that environmental variability and extremes have been difficult to integrate directly into fisheries management. We applied a management strategy evaluation approach for one of Australia's large prawn stocks to test the robustness of harvest control rules to environmental variability. The model ensemble included coupled environmental-population models and an alternative catchability scenario fitted to historical catch per unit effort data. We compared the efficacy of alternative management actions to conserve marine resources under a variable environment while accounting for fisher livelihoods. Model fits to catch per unit effort were reasonably good and similar across operating models (OMs). For models that were coupled to the environment, environmental parameters for El Niño years were estimated with good associated precision, and OM3 had a lower AIC score (77.61) than the base model (OM1, 80.39), whereas OM2 (AIC 82.41) had a similar AIC score, suggesting the OMs were all plausible model alternatives. Our model testing resulted in a plausible subset of management options, and stakeholders selected a permanent closure of the first fishing season based on overall performance of this option; ability to reduce the risk of fishery closure and stock collapse; robustness to uncertainties; and ease of implementation. Our simulation approach enabled the selection of an optimal yet pragmatic solution for addressing economic and conservation objectives under a variable environment with extreme events. 相似文献