全文获取类型
收费全文 | 1064篇 |
免费 | 23篇 |
国内免费 | 12篇 |
专业分类
安全科学 | 19篇 |
废物处理 | 80篇 |
环保管理 | 94篇 |
综合类 | 119篇 |
基础理论 | 234篇 |
污染及防治 | 391篇 |
评价与监测 | 86篇 |
社会与环境 | 70篇 |
灾害及防治 | 6篇 |
出版年
2023年 | 13篇 |
2022年 | 57篇 |
2021年 | 43篇 |
2020年 | 19篇 |
2019年 | 24篇 |
2018年 | 54篇 |
2017年 | 44篇 |
2016年 | 67篇 |
2015年 | 51篇 |
2014年 | 71篇 |
2013年 | 95篇 |
2012年 | 68篇 |
2011年 | 82篇 |
2010年 | 59篇 |
2009年 | 51篇 |
2008年 | 64篇 |
2007年 | 54篇 |
2006年 | 41篇 |
2005年 | 31篇 |
2004年 | 24篇 |
2003年 | 24篇 |
2002年 | 15篇 |
2001年 | 9篇 |
2000年 | 5篇 |
1999年 | 9篇 |
1998年 | 3篇 |
1997年 | 1篇 |
1996年 | 3篇 |
1995年 | 3篇 |
1994年 | 1篇 |
1993年 | 2篇 |
1991年 | 1篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1985年 | 2篇 |
1984年 | 1篇 |
1982年 | 2篇 |
1979年 | 1篇 |
1957年 | 1篇 |
1956年 | 1篇 |
排序方式: 共有1099条查询结果,搜索用时 15 毫秒
981.
Francisco J. Abascal Manuel Quintans Ana Ramos-Cartelle Jaime Mejuto 《Marine Biology》2011,158(5):1175-1184
Nine individuals of shortfin mako, Isurus oxyrinchus, were tracked in the southeastern Pacific Ocean, off northern Chile, by means of pop-up satellite archival tags. No common
pattern was observed in their trajectories, apart from a movement onshore of all the fish tracked during June–August. The
average estimated rate of movement was of c. 27 km day−1. Data were collected and processed for a total of 341 days, including 33 days for one recaptured fish specimen, allowing
high-resolution archived data to be downloaded. The fish spent most of their time in the mixed layer but undertook dives down
to 888 m. Ambient temperatures ranged between 4.6 and 24.1°C, and the sea surface temperatures recorded ranged from 13.4 to
24.1°C during the study period. No clear diel pattern in depth behavior was observed, but mean vertical distribution was deeper
during the daytime. Moreover, a foraging pattern, consisting of rapid descents below the thermocline followed by slower ascents,
was generally observed during daylight hours. Dissolved oxygen concentration and water temperature seem to be the main factors
affecting the vertical range of the species in the area. This is the first study on electronic tagging of the shortfin mako
in the southeastern Pacific Ocean and covers the longest total tracking period reported so far for this species. 相似文献
982.
Sofía Copello Ana I. Dogliotti Domingo A. Gagliardini Flavio Quintana 《Marine Biology》2011,158(6):1247-1257
The study of how and why marine animals distribute themselves at sea has important conservation and management implications
of the species and their habitats. We characterize the oceanographic and biological landscapes of the marine areas used by
breeding Southern Giant Petrels (Macronectes giganteus) at Patagonian colonies and explore inter-sexual and inter-colony differences. The at-sea movements of 16 adults (7 males
and 9 females) were studied by means of satellite telemetry techniques during 1999, 2000, 2002, and 2004 breeding seasons.
Southern Giant Petrels utilized an oceanographic scenario characterized by high productivity, warm sea surface temperature,
and shallow waters. The biological landscape was characterized by a high availability of squid and carrion nearby colonies.
Females spent more time in the shelf break and exploited deeper waters than males. In contrast, males spent more time in coastal
areas and they showed a higher spatial overlap with areas of high squid density than females. Such a prosperous foraging scenario
for both sexes may play a key role in the growth of the breeding population of Southern Giant Petrel Patagonian colonies. 相似文献
983.
Ana Espínola-Arredondo Félix Muñoz-García 《Journal of Environmental Economics and Management》2011,62(3):402-413
This paper analyzes the protection of a common pool resource (CPR) through the management of information. Specifically, we examine an entry deterrence model between an incumbent perfectly informed about the initial stock of a CPR and an uninformed potential entrant. In our model, the appropriation of the CPR by the incumbent reduces both players' future profits from exploiting the resource. In the case of complete information, we show that the incumbent operating in a high-stock common pool overexploits the CPR during the first period since it does not internalize the negative external effect that its first-period exploitation imposes on the entrant's future profits. This inefficiency, however, is absent when the commons totally regenerate across periods. Under incomplete information, we identify an additional form of inefficiency. In particular, the incumbent operating in a low-stock CPR underexploits the resource in order to signal the low available stock to potential entrants, deterring entry. 相似文献
984.
Remote sensing has been used from the 1980s to study inland water quality. However, it was not until the beginning of the twenty-first century that CHRIS (an experimental multi-angle sensor with good spectral and spatial resolutions) and MERIS (with good temporal and spectral resolutions) started to acquire imagery with very good resolutions, which allowed to develop a reliable imagery acquisition system so as to consider remote sensing as an inland water management tool. This paper presents the methodology developed, from the field data acquisition with which to build a freshwater spectral library and the study of different atmospheric correction systems for CHRIS mode 2 and MERIS images, to the development of algorithms to determine chlorophyll-a and phycocyanin concentrations and bloom sites. All these algorithms allow determining water eutrophic and ecological states, apart from generating surveillance maps of toxic cyanobacteria with the main objective of Assessment of the Water Quality as it was used for Monitoring Ecological Water Quality in smallest Mediterranean Reservoirs integrated in the Intercalibration Exercise of European Union Water Framework Directive (WFD). We keep on using it to monitor the Ecological Quality Ratio (EQR) in Spain inland water. 相似文献
985.
Theresa Selfa Carmen Bain Renata Moreno Amarella Eastmond Sam Sweitz Conner Bailey Gustavo Simas Pereira Tatiana Souza Rodrigo Medeiros 《Environmental management》2015,55(6):1315-1326
Across the Americas, biofuels production systems are diverse due to geographic conditions, historical patterns of land tenure, different land use patterns, government policy frameworks, and relations between the national state and civil society, all of which shape the role that biofuels play in individual nations. Although many national governments throughout the Americas continue to incentivize growth of the biofuels industry, one key challenge for biofuels sustainability has been concern about its social impacts. In this article, we discuss some of the key social issues and tensions related to the recent expansion of biofuels production in Mexico, Colombia, and Brazil. We argue that a process of “simplification” of ecological and cultural diversity has aided the expansion of the biofuels frontier in these countries, but is also undermining their viability. We consider the ability of governments and non-state actors in multi-stakeholder initiatives (MSI) to address social and environmental concerns that affect rural livelihoods as a result of biofuels expansion. We analyze the tensions between global sustainability standards, national level policies for biofuels development, and local level impacts and visions of sustainability. We find that both government and MSI efforts to address sustainability concerns have limited impact, and recommend greater incorporation of local needs and expertise to improve governance. 相似文献
986.
Gálvez-Iriqui Alma Carolina García-Romo Joel Said Cortez-Rocha Mario Onofre Burgos-Hernández Armando Burboa-Zazueta María Guadalupe Luque-Alcaraz Ana Guadalupe Calderón-Santoyo Montserrat Argüelles-Monal Waldo Manuel Plascencia-Jatomea Maribel 《Environmental science and pollution research international》2021,28(3):3051-3065
Environmental Science and Pollution Research - Chitosan (CS) nanosystems have potential applications for the control of microorganisms in the medical, environmental, and agrifood fields. In vivo... 相似文献
987.
988.
Summary. Scent signals are the main source of information transmission in carnivores, being particularly important for those with nocturnal
habits like the ringtail (Bassariscus astutus), a Procyonid widely distributed in Mexico. However, faecal marking behaviour of free-ranging ringtails has not been described
previously. The aims of this study were to describe the use of latrines in ringtails and to test if single faeces and latrines
have a marking function, based on the spatial characterisation of the defecation places and revisits to these sites. The study
was conducted at an urban reserve within Mexico City in 2003, where 80 defecation points were analysed. The results showed
that ringtails deposit faeces repeatedly in the same sites (latrines), which contain a variable number of faeces (between
2 and 19). The spatial distribution of latrines was not random, but a selection of substrates and zones that enhanced the
effectiveness as faecal marks was observed. Latrines were preferentially placed on objects above ground level and at road
margins. Latrines and single faeces that were in inconspicuous zones were generally deposited on conspicuous substrates and
latrines and single faeces that were in conspicuous zones were deposited more frequently on inconspicuous substrates. 相似文献
989.