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961.
Free‐ranging domestic cats (Felis catus) incur and impose risks on ecosystems and represent a complex issue of critical importance to biodiversity conservation and cat and human health globally. Prior social science research on this topic is limited and has emphasized feral cats even though owned cats often comprise a large proportion of the outdoor cat population, particularly in urban areas. To address this gap, we examined public risk perceptions and attitudes toward outdoor pet cats across varying levels of urbanization, including along the wildland–urban interface, in Colorado (U.S.A.), through a mail survey of 1397 residents. Residents did not view all types of risks uniformly. They viewed risks of cat predation on wildlife and carnivore predation on cats as more likely than disease‐related risks. Additionally, risk perceptions were related to attitudes, prior experiences with cats and cat–wildlife interactions, and cat‐owner behavior. Our findings suggest that changes in risk perceptions may result in behavior change. Therefore, knowledge of cat‐related risk perceptions and attitudes could be used to develop communication programs aimed at promoting risk‐aversive behaviors among cat owners and cat‐management strategies that are acceptable to the public and that directly advance the conservation of native species.  相似文献   
962.
Seabirds are the most threatened group of marine animals; 29% of species are at some risk of extinction. Significant threats to seabirds occur on islands where they breed, but in many cases, effective island conservation can mitigate these threats. To guide island‐based seabird conservation actions, we identified all islands with extant or extirpated populations of the 98 globally threatened seabird species, as recognized on the International Union for Conservation of Nature Red List, and quantified the presence of threatening invasive species, protected areas, and human populations. We matched these results with island attributes to highlight feasible island conservation opportunities. We identified 1362 threatened breeding seabird populations on 968 islands. On 803 (83%) of these islands, we identified threatening invasive species (20%), incomplete protected area coverage (23%), or both (40%). Most islands with threatened seabirds are amenable to island‐wide conservation action because they are small (57% were <1 km2), uninhabited (74%), and occur in high‐ or middle‐income countries (96%). Collectively these attributes make islands with threatened seabirds a rare opportunity for effective conservation at scale. La Biogeografía de Aves Marinas Amenazadas Globalmente y las Oportunidades de Conservación en Islas  相似文献   
963.
Species that are strong interactors play disproportionately important roles in the dynamics of natural ecosystems. It has been proposed that their presence is necessary for positively shaping the structure and functioning of ecosystems. We evaluated this hypothesis using the case of the world's largest parrotfish (Bolbometopon muricatum), a globally imperiled species. We used direct observation, animal tracking, and computer simulations to examine the diverse routes through which B. muricatum affects the diversity, dispersal, relative abundance, and survival of the corals that comprise the foundation of reef ecosystems. Our results suggest that this species can influence reef building corals in both positive and negative ways. Field observation and simulation outputs indicated that B. muricatum reduced the abundance of macroalgae that can outcompete corals, but they also feed directly on corals, decreasing coral abundance, diversity, and colony size. B. muricatum appeared to facilitate coral advancement by mechanically dispersing coral fragments and opening up bare space for coral settlement, but they also damaged adult corals and remobilized a large volume of potentially stressful carbonate sediment. The impacts this species has on reefs appears to be regulated in part by its abundance—the effects of B. muricatum were more intense in simulation scenarios populated with high densities of these fish. Observations conducted in regions with high and low predator (e.g., sharks) abundance generated results that are consistent with the hypothesis that these predators of B. muricatum may play a role in governing their abundance; thus, predation may modulate the intensity of the effects they have on reef dynamics. Overall our results illustrate that functionally unique and threatened species may not have universally positive impacts on ecosystems and that it may be necessary for environmental managers to consider the diverse effects of such species and the forces that mediate the strength of their influence. Efectos Positivos y Negativos de un Pez Loro Amenazado Sobre Ecosistemas Arrecifales  相似文献   
964.
Culturomic tools enable the exploration of trends in human–nature interactions, although they entail inherent biases and necessitate careful validation. Furthermore, people may engage with nature across different culturomic data sets differently. We evaluated people's digital interest and engagement with plant species based on Wikipedia and Google data and explored the conservation implications of these temporal interest patterns. As a case study, we explored the digital footprints of the most popular plant species in Israel. We analyzed 4 years of daily page views from Hebrew Wikipedia and 10 years of daily Google search volume in Israel. We modeled popularity of plant species in these 2 data sets based on a suite of plant attributes. We further explored the seasonal trends of people's interest in each species. We found differences in how people interacted digitally with plants in Wikipedia and Google. Overall, in Google, searches for species that have utility to humans were more common, whereas in Wikipedia, plants that serve as cultural emblems received more attention. Furthermore, in Google, popular species attracted more attention over time, opposite to the trend in Wikipedia. In Google, interest in species with short bloom duration exhibited more pronounced seasonal patterns, whereas in Wikipedia, seasonality of interest increased as bloom duration increased. Together, our results suggest that people's digital interactions with nature may be inherently different depending on the sources explored, which may affect use of this information for conservation. Although culturomics holds much promise, better understanding of its underpinnings is important when translating insights into conservation actions.  相似文献   
965.
辽河四平段流域河流沉积物微生物群落多样性和结构分析   总被引:5,自引:4,他引:1  
沉积物微生物群落在水生态系统的物质循环中发挥着关键的作用,群落结构组成的变化经常与环境的改变有关.以辽河四平段流域为研究区域,运用高通量测序结果对沉积物微生物群落的结构组成和多样性进行分析.结果表明,辽河四平段流域河流沉积物微生物群落α多样性以北河支流最高,干流次之,南河支流最低;β多样性表现为干流、北河支流和南河支流的微生物群落的相似性较低,差异性较大.变形菌门是该流域微生物群落门水平上丰度最高的优势菌门,并且与其他东北地区的河流类似,该流域河流沉积物中的厚壁菌门含量较低;γ-变形菌纲是该流域河流沉积物微生物群落占比最高的菌纲,但是β-变形菌纲在该流域丰度很低;而属于β-变形菌纲Ellin6067菌属在该流域分布很广.环境因子例如沉积物重金属和水体理化性质也会对微生物群落的多样性和种群结构产生多种影响.结果为实现修复辽河四平段流域河流的水体污染工作提供了理论依据.  相似文献   
966.
中国镉超富集植物的物种、生境特征和筛选建议   总被引:2,自引:1,他引:1  
赵晓峰  雷梅  陈同斌 《环境科学》2023,44(5):2786-2798
植物修复作为一项绿色且有效的原位修复重金属污染土壤技术,在近20年引起了中国学者的关注并取得了一系列成果.通过检索镉超富集植物相关关键词,对过去20 a(2002~2021年)科技文献中报道的中国镉超富集植物的物种特征、野外发现地在中国各植被地带的分布、原生境特征、地质特征和镉的地球化学进行归纳总结,为镉超富集植物的筛选提供建议.结果表明,目前报道的镉超富集植物有45种.在植物物种上,隶属22科,36属,其中菊科(Compositae)植物最多,为14种.由野外调查发现的镉超富集植物有25种,主要发现于亚热带常绿阔叶林区域,其主要生长于铅锌矿周围的高浓度镉土壤上.归纳总结发现,丰富的植物物种资源、高浓度重金属土壤和长时间的驯化共同促进了超富集植物的形成.因此,具备这3点的区域可以视为超富集植物存在的高概率区域,并且超富集植物的野外筛选可以围绕此展开.最后,提出可以通过高概率区域识别和调查、富集能力验证、富集能力逆境习得筛查、生态型筛查、继代遗传检验和修复能力验证这6步,来进行超富集植物的筛选和植物超富集能力的鉴定.  相似文献   
967.
基于2015~2021年的1~3月北京市大气PM2.5浓度与化学组成长期观测数据,分析了2022年北京冬季奥林匹克运动会(冬奥会)和北京冬季残疾人奥林匹克运动会(冬季残奥会)历史同期的PM2.5污染态势、化学组成特征以及潜在源区.2015~2018年的1~3月重污染[日均ρ(PM2.5)>75 μg·m-3]天数以及重污染期间PM2.5平均值下降十分显著,之后这两者未发生明显改变.2018~2021年的1~3月每年平均发生重污染23 d,重污染天ρ(PM2.5)平均值约为120.0 μg·m-3.2015~2021年的1~3月超长重污染过程(连续重污染超过5 d)平均每年发生2~3次,其中2021年发生3次,且持续时间最长达到8 d.历年冬奥会历史同期发生重污染的天数为2~9 d,春节期间烟花爆竹大量燃放可能是该时期重污染发生的重要原因之一;冬季残奥会历史同期重污染天数一般为1~5 d,但2021年受频繁出现的静稳天气影响,重污染天数高达9 d.在同时段重污染期间,PM2.5化学组成均以二次组分为主,例如在PM2.5可测组分中,2020年NO3-质量分数高达46%,较同年清洁天(11%)显著增加;SO42-质量分数为12%~19%,说明当前硫酸盐污染仍不容忽视.北京市1~3月PM2.5主要贡献区域包括内蒙古自治区中西部、河北省、天津市、山西省、陕西省、山东省中西部和河南省北部.研究结果将为北京市冬季空气质量持续改善以及2022年冬奥会与冬季残奥会期间北京市环境空气质量保障提供科学依据.  相似文献   
968.
为了解不同水文期三峡库区支流附石藻类与环境因子的关系,分别于丰水期(2016年8月)、枯水期(2016年11月)及平水期(2017年3月)这3个时期,对三峡库区支流梅溪河非回水区和回水区的26个采样点附石藻类进行采样并对其相关环境因子进行分析.结果表明,3个水情期,共鉴定出附石藻类5门47属106种(含变种).其中,丰水期采集到73种,隶属5门38属,枯水期67种,隶属4门36属,平水期63种,隶属4门33属.丰水期、枯水期和平水期优势种分别为19种、17种和18种,丰水期的主要优势种属为曲壳藻属、束丝藻属和席藻属,枯水期为异极藻属、曲壳藻属和舟形藻属,而平水期为异极藻属、曲壳藻属和色球藻属.3个时期共有的优势种为扁圆卵形藻(Cocconeis placentula)、曲壳藻(Achnanthes sp.)、近棒形异极藻(Gomphonema subclavatum)、小型异极藻(G.parvulum)、小型舟形藻(Navicula parva)和缢缩异极藻(G.constrictum).冗余(RDA)分析表明,回水区的附石藻类优势种相对丰度与电导率(Spc)、溶氧(DO)、pH、总磷(TP)和总氮(TN)的变化相关,而在非回水区,附石藻类优势种相对丰度主要与电导率(Spc)、pH、总磷(TP)、水温(WT)和流速(v)的变化有关.3个时期,影响附石藻类环境因子具有差异,然而,3个时期小型异极藻、缢缩异极藻和曲壳藻等优势种的相对丰度均与总磷呈负相关,与pH呈正相关.这些结果表明三峡库区不同水文期及水环境变化对附石藻类群落组成具有重要影响,导致群落结构发生变化.  相似文献   
969.
通过对2007--2011年阳宗海砷浓度和藻类数量、种类变化数据的研究,分析砷浓度对藻类的影响。  相似文献   
970.
Lake littoral zones are characterized by heterogeneity in the biogeochemistry of nutrient elements. This study aimed to explore the relationship between the nitrous oxide reductase gene (nosZ)-encoding denitrifier community composition/abundance and N2O reduction. Five samples (deep sediment, near-transition sediment, transition site, near-transition land and land soil) were collected along a littoral gradient of eutrophic Baiyangdian Lake, North China. To investigate the relationship between the nosZ-encoding denitrifier community structure and N2O reduction, the nosZ-encoding denitrifier community composition/abundance, potential denitrification rate (DNR) and potential N2O production rate (pN2O) were investigated using molecular biological technologies and laboratory incubation experiments. The results showed that the average DNR of sediments was about 25 times higher than that of land soils, reaching 282.5 nmol N/(g dry weight (dw)·hr) and that the average pN2O of sediments was about 3.5 times higher than that of land soils, reaching 15.7 nmol N/(g dw·hr). In the land area, the nosZ gene abundance showed a negative correlation with the N2O/(N2O+N2) ratio, indicating that nosZ gene abundance dominated N2O reduction both in the surface soils of the land area and in the soil core of the transition site.Phylogenetic analysis showed that all the nosZ sequences recovered from sediment clustered closely with the isolates Azospirillum largimobile and Azospirillum irakense affiliated to Rhodospirillaceae in alpha-Proteobacteria, while about 92.3% (12/13) of the nosZ sequences recovered from land soil affiliated to Rhizobiaceae and Bradyrhizobiaceae in α-Proteobacteria. The community composition of nosZ gene-encoding denitrifiers appeared to be coupled with N2O reduction along the littoral gradient.  相似文献   
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