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91.
工业城市生活垃圾的预测量与对策研究 总被引:2,自引:0,他引:2
利用灰色理论中的GM(1,1)预测模型对某工业城市生活垃圾产生量进行预测。根据垃圾量的发展趋势。提出在分类收集的基础上采取综合利用、焚烧和卫生填埋的处理方法。并对综合处理方法中的管理与技术问题作了探讨。 相似文献
92.
在5种水力负荷条件下,采用连续进水、间歇排水的运行方式,对2种垂直流湿地处理低浓度生活污水的去除效果进行了研究.结果表明,在水力负荷为0.085,0.106,0.141,0.212m3/(m2d)的条件下,多层填料(1#)湿地和双层填料(2#)湿地对CODCr和NH4+-N的去除无明显差异,出水CODCr和NH4+-N浓度均低于30mg/L和5mg/L.两垂直流湿地CODCr净化负荷与有机污染负荷之间呈显著的正相关关系(n=4R2>0.98).垂直流湿地中氮的去除主要是依靠微生物的硝化和反硝化作用;进水水质、水力负荷和温度等影响湿地系统硝化和反硝化作用的进行,水力负荷为0.141m3/(m2d)时,总氮(TN)去除效率与有机污染负荷呈正相关. 相似文献
93.
Albert W. Musschenga 《Journal of Agricultural and Environmental Ethics》2002,15(2):171-186
There is an ongoing debate in animalethics on the meaning and scope of animalwelfare. In certain broader views, leading anatural life through the development of naturalcapabilities is also headed under the conceptof animal welfare. I argue that a concern forthe development of natural capabilities of ananimal such as expressed when living freelyshould be distinguished from the preservationof the naturalness of its behavior andappearance. However, it is not always clearwhere a plea for natural living changes overinto a plea for the preservation of theirnaturalness or wildness. In the first part ofthis article, I examine to what extent theconcerns for natural living meet ``theexperience requirement.' I conclude that someof these concerns go beyond welfare. In thesecond part of the article. I ask whether wehave moral reasons to respect concernsfor the naturalness of an animal's living thattranscend its welfare. I argue that the moralrelevance of such considerations can be graspedwhen we see animals as entities bearingnon-moral intrinsic values. In my view the``natural' appearance and behavior of an animalmay embody intrinsic values. Caring for ananimal's naturalness should then be understoodas caring for such intrinsic values. Intrinsicvalues provide moral reasons for action iffthey are seen as constitutive of the good lifefor humans. I conclude by reinterpreting,within the framework of a perfectionist ethicaltheory, the notion of indirect dutiesregarding animals, which go beyond andsupplement the direct duties towardsanimals. 相似文献
94.
中国城市化与城镇居民住房 总被引:4,自引:0,他引:4
王晓东 《中国人口.资源与环境》1998,8(1):81-85
随着住房制度改革的不断深入,我国城镇居民人均居住面积有所提高,居住水平有所改善。但是,中国城市化发展的特点很容易造成城镇居民居住水平提高的假象。本文分析了造成这些假象的原因。 相似文献
95.
We used interdemic variation in the tendency to form mixed-species groups to examine the costs and benefits of association
among the primates of Kibale National Park, Uganda. A year-long survey of six sites revealed that the amount of time that
the five common diurnal primates [red colobus (Procolobus
tephrosceles), black-and-white colobus (Colobus
guereza), redtail monkeys (Cercopithecus
ascanius), blue monkeys (Cercopithecus
mitis), and grey-cheeked mangabeys (Lophocebus
albigena)] spent in mixed-species groups varied dramatically among sites. In many cases, the proportion of time that species associated
was positively related to their densities. By using detailed behavioral observations of redtail monkeys and red colobus made
over 4 years (2660 h) at four sites, we were able to reject the null hypothesis that associations occur by chance for only
one of four sites. However, a correlative approach exploring the costs and benefits of association suggests that ecological
variables do influence association patterns. We found that redtail monkeys and red colobus overlapped in diet (19.2% of their
foraging effort) and traveled further when in mixed-species groups than when alone. Having demonstrated this, we examined
the applicability of the ecological constraints model for predicting the proportion of the time spent in mixed-species groups
based on food availability. For this analysis we concentrated on red colobus from the site with 35 months of observation and
demonstrated that their tendency to be in mixed- species groups was related to food availability. We used two methods to examine
if mixed-species associations function to decrease predation risk. First, chimpanzees are known to prey heavily on red colobus,
but rarely kill other primates. The time red colobus spent in mixed-species groups was correlated to chimpanzee density, but
it was not for the other monkey species, suggesting that mixed-species groups serve to decrease predation risk. Second, when
red colobus groups contain more infants and are presumably at the greatest risk of predation, they form mixed-species groups
most often. These results demonstrate that the costs and benefits of mixed-species associations vary dramatically over small
spatial and temporal scales. If such variation is generally the case, then studies conducted at different locations or different
times could easily highlight the importance of difference selective agents in favoring mixed-species associations.
Received: 10 February 1999 / Received in revised form: 16 September 1999 / Accepted: 2 October 1999 相似文献
96.
Increasing empirical and theoretical evidence supports the idea that sympatric speciation is operating, for example, in species
flocks comprising several closely related fish species within one lake. Divergent natural selection (promoting spatial and
food niche partitioning) and sexual selection (assortative mating) have been identified as key selection factors in intralacustric
adaptive radiations. However, the evolution of social behaviors accompanying such adaptive radiations is less well understood.
Using a phylogenetically young species flock of pupfish (Cyprinodon spp.) as a model, we examined differences among six sympatric species and compared their shoaling, aggressive, and territorial
behaviors with that of a sister species (C. artifrons). Despite an estimated age of the species flock of less than 8,000 years, pronounced behavioral differentiation was found.
C. simus, the smallest species in the flock, shoaled more than the other species and was less aggressive and less territorial than
C. beltrani. F1-hybrids between C. simus males and C. beltrani females showed an intermediate expression of shoaling and aggressive behavior. Niche partitioning among the members of this
species flock appears to be accompanied by rapid divergent evolution of social behaviors. We discuss the potential role of
phenotypic plasticity and within-species variation of social behaviors for such rapid behavioral diversifications in sympatric
speciation processes. 相似文献
97.
选取小球衣藻(Chlamydomonas microsphaera)、铜绿微囊藻(Microcystis aeruginosa)、钝顶螺旋藻(Spirulina platensis)和四尾栅藻(Scenedesmus quadricauda)等4种微藻,通过室内模拟实验,对水体中的Cd2+进行吸附,并对吸附Cd2+的微藻分别采用去离子水、0.2 mol·L-1 CaCl2与研磨处理,测定Cd2+的解脱量,研究活体微藻对重金属离子的富集特征与机理。结果表明:4种活体微藻均对水体中Cd2+有较强的富集能力,在Cd2+初始浓度为10 mg·L-1、溶液pH为7.0的实验条件下,小球衣藻富集量可达76.34 mg·g-1,铜绿微囊藻、钝顶螺旋藻和四尾栅藻富集量分别为24.78、15.28 和 9.85 mg·g-1,说明微藻是良好的重金属吸附剂;4种活体微藻对Cd2+的富集特征均符合准二级动力学方程(R2>0.99),反映出活体微藻对Cd2+的富集主要是一种化学行为;活体微藻对Cd2+的富集主要是离子交换形式的化学吸附,富集比例均在60%以上,其中小球衣藻最高,达86.51%。除化学吸附外,还包括物理吸附与生物吸收,生物吸收所占富集比例为6.75%~18.96%,而物理吸附量最少,为3.02%~14.63%。 相似文献
98.
Anthony M. Levenda 《Local Environment》2019,24(7):565-579
ABSTRACTThe proliferation of smart technologies, big data, and analytics is being increasingly used to address urban socio-environmental problems such as climate change mitigation and carbon control. Electricity systems in particular are being reconfigured with smart technologies to help integrate renewable generation, enhance energy efficiency, implement new forms of pricing, increase control and automation, and improve reliability. Many of these interventions are experimental, requiring real-world testing before wider diffusion. This testing often takes place in “urban living labs,” integrating urban residents as key actors in experimentation with goals for broader sustainability transitions. In this paper, I investigate one such urban living lab focused on smart grid research and demonstration in a residential neighbourhood in Austin, Texas. I develop a framework based in governmentality studies to critically interrogate urban experimentation. Findings suggest that the focus of experimentation devolves urban imperatives into individual responsibilities for socio-environmental change. Managing carbon emissions through energy efficiency, renewable energy, and conservation is promoted as a form of self-management, wherein households reconfigure everyday activities and/or adopt new technologies. At the same, sociotechnical interventions are shaped by technology companies, researchers, and policy-makers marking a central feature of contemporary urban entrepreneurialism. This skews the potential of active co-production, and instead relies on the delegation of responsibility for action to a constrained assemblage of smart technologies and smart users. 相似文献
99.
仙居县城乡居民消费差异的生态足迹分析 总被引:20,自引:0,他引:20
根据生态足迹理论,以浙江省仙居县为例,利用统计调查和问卷调查资料,分别计算了城乡居民生活消费的生态系统占用情况。计算结果表明,该地城市居民的生活消费所占用的生态系统是农村居民所占用的1.73倍,差异最大的是草地,其次是水域、建筑用地、化石能源和耕地,对于林地的占用则是农村居民大于城市居民。 相似文献
100.
In several vertebrate taxa, males and females differ in the proportions of time they individually devote to vigilance, commonly
attributed to sex differences in intra-specific competition or in absolute energy requirements. However, an effect of sex
on collective vigilance is less often studied (and therefore rarely predicted), despite being relevant to any consideration
of the adaptiveness of mixed- vs single-sex grouping. Controlling for group size, we studied the effect of sex on vigilance
in the sexually dimorphic eastern grey kangaroo Macropus giganteus, analysing vigilance at two structural levels: individual vigilance and the group’s collective vigilance. Knowing that group
members in this species tend to synchronise their bouts of vigilance, we tested (for the first time) whether sex affects the
degree of synchrony between group members. We found that females were individually more vigilant than males and that their
vigilance rate was unaffected by the presence of males. Collective vigilance did not differ between female-only and mixed-sex
groups of the same size. Vigilance in mixed-sex groups was neither more nor less synchronous than in single-sex groups of
females, and the presence of males seemed not to affect the degree of synchrony between females. Sixty-six percent of vigilant
acts were unique (performed when no other kangaroo was alert), and only about one unique vigilant act in every three induced
a collective wave of vigilance. The proportions of vigilant acts that were unique were 60% for females but only 46% for males.
However, the sexes differed little in the rates at which their unique vigilant acts were copied. This limited study shows
that the differences in vigilance between male and female kangaroos had no discernible effect upon collective vigilance. 相似文献