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151.
Feral cats are abundant in many parts of the world and a source of conservation conflict. Our goal was to clarify the beliefs and desires held by stakeholders regarding feral cat abundance and management. We measured people's desired abundance of feral cats in the Hawaiian Islands and identified an order of preference for 7 feral cat management techniques. In 2011 we disseminated a survey to 5407 Hawaii residents. Approximately 46% of preidentified stakeholders and 20% of random residents responded to the survey (1510 surveys returned). Results from the potential for conflict index revealed a high level of consensus (86.9% of respondents) that feral cat abundance should be decreased. The 3 most common explanatory variables for respondents’ stated desires were enjoyment from seeing feral cats (84%), intrinsic value of feral cats (12%), and threat to native fauna (73%). The frequency with which respondents saw cats and change in the perceived abundance of cats also affected respondent's desired abundance of cats; 41.3% of respondents stated that they saw feral cats daily and 44.7% stated that the cat population had increased in recent years. Other potential environmental impacts of feral cats had little affect on desired abundance. The majority of respondents (78%) supported removing feral cats from the natural environment permanently. Consensus convergence models with data from 1388 respondents who completed the relevant questions showed live capture and lethal injection was the most preferred technique and trap‐neuter‐release was the least preferred technique for managing feral cats. However, the acceptability of each technique varied among stakeholders. Our results suggest that the majority of Hawaii's residents would like to see effective management that reduces the abundance of feral or free‐roaming cats. Deseos y Preferencias de Manejo de las Partes Interesadas con Respecto a los Gatos Ferales en las Islas Hawaianas. 相似文献
152.
太湖梅梁湾浮游动物群落结构长期变化特征(1997~2017年) 总被引:5,自引:3,他引:2
浮游动物作为水体食物链的重要组成部分,在湖泊生态系统中发挥着重要作用.然而,作为水质重要监测指标,由于浮游动物群落结构长期连续监测数据的缺失,导致关于浮游动物群落结构长期变化特征的认识较为缺乏.基于太湖梅梁湾1997~2017年逐月连续监测数据,研究了浮游动物群落结构的长期变化特征,探讨了其与环境因子的关系.结果显示,在此期间,太湖梅梁湾浮游动物丰度和生物量均显著下降(P<0.05).其中,轮虫和桡足类丰度和生物量均缓慢下降,枝角类丰度处于波动而生物量表现为显著下降(P<0.05).枝角类生物量对太湖梅梁湾浮游动物生物量的贡献最大.小型的枝角类和桡足类的优势度随着轮虫丰度的降低而增大,浮游动物的平均体型显著减小(P<0.05),浮游动物呈现出小型化演化特征,并潜在减弱对浮游植物的下行效应.此外,浮游动物丰度和生物量在春季呈上升趋势而在秋冬季呈下降趋势,并在9月达到最大值1406.70 ind.·L-1和25.64 mg·L-1.而在夏季它们的变化趋势则相反.Pearson相关性分析显示,浮游动物群落结构主要与水体物理特征(碱度、电导率、水深、悬浮物质和水温)、叶绿素a和氮元素密切相关(P<0.05),说明太湖梅梁湾水体富营养化对浮游动物的群落结构具有重要影响. 相似文献
153.
培养条件下双酚A对稻田土壤微生物群落特征的影响 总被引:3,自引:1,他引:2
双酚A(bisphenol A,BPA)作为人工合成的典型环境激素分布极为广泛,然而不同浓度和土壤通气条件下BPA对土壤微生物群落(细菌、真菌)特征的影响鲜见报道.本文采用荧光定量PCR(fluorescence quantitative PCR)技术、聚合酶链式反应-变性梯度凝胶电泳(polymerase chain reaction-denaturing gradient gel electrophoresis,DGGE)相结合的方法研究不同BPA浓度(0、0.25、0.50、1.00、2.00 mg·kg-1)和土壤通气条件(有氧和厌氧)对稻田土壤微生物群落特征的影响。结果表明,土壤通气条件一致情况下(有氧条件或者厌氧条件下),不同BPA浓度添加下微生物丰度指数差异显著,而微生物均匀度指数、香农维纳多样性指数及丰富度指数差异不显著;BPA浓度为0.50 mg·kg-1时,微生物基因丰度在厌氧条件下达到最大值,而在有氧条件下微生物基因丰度却达到最小值;双因素方差分析表明:BPA浓度、土壤通气条件及其交互作用对细菌基因丰度影响差异显著,而只有土壤通气条件对真菌基因丰度影响差异显著.结果表明相对于微生物多样性指数,丰度指数能更加灵敏地指示土壤微生物多样性的变化,BPA浓度为0.50 mg·kg-1时是影响土壤微生物基因丰度变化的一个临界值,相对于真菌基因丰度指数而言,细菌基因丰度指数对BPA添加浓度及土壤通气条件响应更加灵敏. 相似文献
154.
155.
Host specificity of mites with respect to different species of small mammals in forest ecosystems was studied. The preferences of some parasites for certain host species differed from those described previously. In some cases, most parasites preferred to feed on the species that were most numerous in a certain biogeocenosis, rather than on their specific hosts. Conversely, other species of mites fed mostly on their specific hosts, irrespective of their low abundance, thus manifesting close connections with these mammals. Two mite species, Myonyssus dubinini and M. rossicus, were found in the study region for the first time. 相似文献
156.
157.
158.
大亚湾春季小型底栖动物初步研究 总被引:1,自引:0,他引:1
2010年4月对大亚湾海域的小型底栖动物丰度和生物及其它生物指标进行了研究。结果表明,小型底栖动物的平均丰度和生物量分别为(158.96±57.22)/cm2和(94.31±33.40)μg/cm2干质量,生产量为(848.76±300.61)μg/(cm2.a)。在分选的16个主要类群中,海洋线虫在丰度(97.64%)和生物量(65.83%)上均为绝对优势类群,桡足类(0.91%)在丰度上居其次,而多毛类(14.32%)在生物量上为第二优势类群。在垂直分布上,约49.82%的小型底栖动物分布在0~2cm层中;各类群中,桡足类的表层分布更为显著,线虫、桡足类以及多毛类位于0~2 cm表层的比例分别为49.55%、75.19%和44.71%。Pearson显著相关分析表明,小型底栖动物的丰度与生物量与环境因子均无显著相关关系,而通过单因素方差分析得知,各站位间的丰度与生物量差异均极显著(P<0.001)。通过对香浓威纳、Pielou均匀度等生物指数的计算以及N/C比值的统计均可总结出,位于澳头养殖区的站位群落的多样性较差,稳定度较低,因此得出生物指数和N/C值可作为生态评估的参考指标。 相似文献
159.
低温高海拔湖泊岸边带厌氧氨氧化菌的存在、生物多样性及活性——以天山天池为例 总被引:3,自引:1,他引:2
本文旨在通过聚合酶链反应PCR、构建克隆文库、15N同位素示踪等技术研究厌氧氨氧化细菌在以天山天池为代表的高海拔低温水生态系统中的存在、发生、活性及对氮循环的影响.通过定量PCR测得天山天池沉积物厌氧氨氧化菌的丰度为(2.93×105±0.25×105)copy/每克干沉积物土样,证明了存在有一定数量的厌氧氨氧化菌;在分别对厌氧氨氧化细菌的16S rRNA和hzs B功能基因构建克隆文库,并对阳性克隆进行生物多样性分析,发现天山天池沉积物中16S rRNA阳性克隆子均属于同一个独立操作单元,与已知的厌氧氨氧化菌的相似度高于99%;而hzs B功能基因克隆文库中,其生物多样性略高于16S rRNA文库.通过同位素示踪技术测得该样品的厌氧氨氧化速率为1.162 nmol·g-1·h-1,其对氮气生成的贡献率高达82%,远高于以往报道的淡水环境中厌氧氨氧化对氮气生成的贡献率.推断高海拔和低温等环境可能不是限制厌氧氨氧化细菌生长的关键因素. 相似文献
160.
Anja Byg Jaana Vormisto Henrik Balslev 《Environment, Development and Sustainability》2006,8(4):495-506
Plant families differ greatly with regard to their usefulness to humans. Within families there are also large differences in the usefulness between species; some are used for many different purposes, while most are used for few or no purposes. Which ones and to what extent species are used often varies between areas and cultural groups. To better understand variation in speciesȁ9 usefulness we studied the use of different palm species (Arecaceae) among two socio-cultural groups (one indigenous and one colonist group of mixed ethnic descent) living in the same area. We used regression and correlation analyses to determine to what degree use is related to ecological and morphological characteristics, to geographical differences in abundance, and to peopleȁ9s perceptions of speciesȁ9 availability. We found that abundance and height were the most important characteristics related to use, possibly due to the effect of height and abundance on salience, search time, and (for height) suitability for different purposes. Abundance was most important for palm heart extraction, probably due to the opportunistic nature of this activity. There was no difference between socio-cultural groups with regard to the relationship between palm abundance and use, but abundance seemed to be more decisive for people who used moderate amounts of palms. Finally, it was seen that peopleȁ9s estimates of palm abundance were not related to our measurements of abundance, which may be due to use of different spatial scales in evaluating abundance and to the subjective nature of terms such as “rare” and “abundant”. 相似文献