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Abstract

The overgrowth of population and deterioration of environment are two serious problems of China. They pose a strong challenge to China's economic and social development. This article discusses the challenge and proposes some countermeasures for China to cope with these problems.  相似文献   
2.
This study investigated hormonal and demographic processes underlying unimale and multimale mating systems in primates. Reproductive skew and challenge models of male competition provide conflicting predictions of the relationship of male residence to group composition and androgen regulation. These predictions were tested using endocrine and socioecological data from Kenyan vervet monkeys (Cercopithecus aethiops). Serum samples from 57 adult male monkeys, drawn from 19 separate groups and 4 populations, were assayed for testosterone by radioimmunoassay. Male ability to respond to conspecific challenge was assessed by their testosterone response to the capture protocol.Analyses showed that reproductive skew models were useful predictors of intergroup and interpopulation variation in male residence and T profiles. The Limited Control model of male residence was supported by positive correlations of the number of males per group with the number of females without dependent offspring, demonstrating that monopolization potential was a key determinant of male residence. Testosterone concentrations under conditions that elevated serum levels were positively correlated with infanticide risk, supporting the Concession model. Population comparisons provided evidence for increased T responsiveness where groups were predominantly unimale. Unimale populations were from sites with higher rainfall, suggesting that ecological factors contributed to population differences in male residence and T regulation.For species name, we follow the 2000 taxonomy of the IUCN/SSC Primate Specialist Groups workshop (Grubb et al. 2003)  相似文献   
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走向市场是环境监测发展的必然趋势   总被引:1,自引:0,他引:1  
阐述了作为事业单位的环境监测行业在市场化经济中的改革问题。指出中国进入WTO后,将遇到体制、机制转变,缺乏准则规范和工作效率低下.资金不足和人才流失.以及面对市场化经济不适应等问题。提出国内环境监测行业在市场化经济的发展中。首先应改变无偿为政府提供数据服务的情况,要敢于摆脱落后机制的诸多束缚和思想观念上的因循守旧,将精力投入到开发市场和拓宽监测领域中去,同时提出了积极转变机制、拓展融资渠道、开拓监测领域、适应市场机制、培育和规范环境监测市场的对策。  相似文献   
4.
阐述了当前环境监测的现状,指出了新常态下环境监测的机遇和挑战,提出了环境监测要抓住机遇,面对挑战,充分发挥职能,保证环境监测数据真实,完善环境监测体系,深度运用环境监测数据,实行信息公开。  相似文献   
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The loss of forest is a leading cause of species extinction, and reforestation is 1 of 2 established interventions for reversing this loss. However, the role of reforestation for biodiversity conservation remains debated, and lacking is an assessment of the potential contribution that reforestation could make to biodiversity conservation globally. We conducted a spatial analysis of overlap between 1,550 forest-obligate threatened species’ ranges and land that could be reforested after accounting for socioeconomic and ecological constraints. Reforestation on at least 43% (∼369 million ha) of reforestable area was predicted to potentially benefit threatened vertebrates. This is approximately 15% of the total area where threatened vertebrates occur. The greatest opportunities for conserving threatened vertebrate species are in the tropics, particularly Brazil and Indonesia. Although reforestation is not a substitute for forest conservation, and most of the area containing threatened vertebrates remains forested, our results highlight the need for global conservation strategies to recognize the potentially significant contribution that reforestation could make to biodiversity conservation. If implemented, reforestation of ∼369 million ha would also contribute substantially to climate-change mitigation, offering a way to achieve multiple sustainability commitments at once. Countries must now work to overcome key barriers (e.g., unclear revenue streams, high transaction costs) to investment in reforestation.  相似文献   
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本文对全球环境治理的现状,中国当前在全球环境治理中的作用与面临的挑战,以及中国如何更好地参与全球环境治理进行了系统的总结.主要内容包括:全球环境治理成为全球治理的重要内容,全球环境治理当前由发达国家主导,全球环境治理中各方利益更加分化,非政府组织的影响越来越大,全球环境治理当前进展缓慢;中国日益成为全球环境治理的关注焦点,中国国内环保工作与全球环境治理有着巨大差别,中国国情的不断变化导致在全球环境治理中的立场摇摆;中国参与全球环境治理的能力不足、中国的非政府组织力量薄弱;中国应明确自身在全球环境治理中的利益,加强全球环境治理的意识,从熟悉学习阶段向主动参与制定规则转变,发挥我国环境非政府组织在全球环境治理中的积极作用,开展全球环境治理专项研究,加强全球环境治理人才队伍建设.  相似文献   
7.
Despite the many benefits that testosterone has on male reproduction, sustaining high levels of testosterone for long periods can be costly. The challenge hypothesis predicts that males will show temporarily sustained elevations of testosterone at critical periods, counterbalanced by decreased levels during noncritical periods. We investigated male testosterone measures extracted from fecal samples in a group of chacma baboons (Papio hamadryas ursinus) living in the Okavango Delta, Botswana. Because rank serves as a proxy for competition for mates, we examined how male testosterone was related to dominance rank, age, aggression, and mating activity. Males showed an elevation in testosterone at maturity; young adult males had the highest testosterone levels followed by a steady decline with age. Among dispersing males, testosterone was temporarily elevated in the month following dispersal. After controlling for age, testosterone and rank were unrelated, but testosterone and changes in rank were positively correlated, such that males rising in rank had higher testosterone than males falling in rank. Thus, for males in this group, testosterone was predictive of a male's rank trajectory, or future rank. Similarly, male testosterone levels predicted future, rather than current, mating activity. Finally, male testosterone and aggression rates were unrelated during stable periods in the dominance hierarchy but positively related during unstable periods when high ranks were being contested. In general, our results support the challenge hypothesis with males exhibiting elevated testosterone in association with the acquisition of high rank (ensuring access to mates), rather than with mating itself.  相似文献   
8.
目前全球经济一体化格局的形成和全球环境日益恶化 ,公众环境意识的提高和消费需求观念的变革给未来社会支柱产业之一——环保产业兴起、发展提供了一个良好的舞台。尤其是中国入世后 ,环保产业面临哪些风险及如何面对困境和挑战、机遇是我们今天关注的焦点。面对困境和挑战、风险和机遇 ,作出什么样的策略直接影响着我国整个生态环境的改善和环保产业的发展。本文拟对此作些浅探 ,并提出了相应的对策。  相似文献   
9.
对我国"十三五"时期环境保护国际合作形势进行了研判,分析了将面临的机遇和挑战,并提出了环境保护国际合作的对策和建议,以期为做好新时期的环境保护国际合作工作提供参考。  相似文献   
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