全文获取类型
收费全文 | 1081篇 |
免费 | 13篇 |
国内免费 | 15篇 |
专业分类
安全科学 | 24篇 |
废物处理 | 44篇 |
环保管理 | 121篇 |
综合类 | 112篇 |
基础理论 | 277篇 |
环境理论 | 1篇 |
污染及防治 | 351篇 |
评价与监测 | 109篇 |
社会与环境 | 63篇 |
灾害及防治 | 7篇 |
出版年
2023年 | 18篇 |
2022年 | 43篇 |
2021年 | 47篇 |
2020年 | 25篇 |
2019年 | 19篇 |
2018年 | 42篇 |
2017年 | 49篇 |
2016年 | 67篇 |
2015年 | 42篇 |
2014年 | 79篇 |
2013年 | 102篇 |
2012年 | 56篇 |
2011年 | 79篇 |
2010年 | 69篇 |
2009年 | 45篇 |
2008年 | 54篇 |
2007年 | 66篇 |
2006年 | 41篇 |
2005年 | 23篇 |
2004年 | 25篇 |
2003年 | 26篇 |
2002年 | 17篇 |
2001年 | 10篇 |
2000年 | 6篇 |
1999年 | 7篇 |
1998年 | 6篇 |
1997年 | 7篇 |
1996年 | 2篇 |
1995年 | 4篇 |
1994年 | 6篇 |
1993年 | 4篇 |
1992年 | 4篇 |
1991年 | 4篇 |
1990年 | 3篇 |
1989年 | 2篇 |
1985年 | 3篇 |
1984年 | 1篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1976年 | 1篇 |
1966年 | 1篇 |
1957年 | 1篇 |
排序方式: 共有1109条查询结果,搜索用时 15 毫秒
111.
Steven?J.?CookeEmail authorView authors OrcID profile Eduardo?G.?Martins Daniel?P.?Struthers Lee?F.?G.?Gutowsky Michael?Power Susan?E.?Doka John?M.?Dettmers David?A.?Crook Martyn?C.?Lucas Christopher?M.?Holbrook Charles?C.?Krueger 《Environmental monitoring and assessment》2016,188(4):239
Freshwater fish move vertically and horizontally through the aquatic landscape for a variety of reasons, such as to find and exploit patchy resources or to locate essential habitats (e.g., for spawning). Inherent challenges exist with the assessment of fish populations because they are moving targets. We submit that quantifying and describing the spatial ecology of fish and their habitat is an important component of freshwater fishery assessment and management. With a growing number of tools available for studying the spatial ecology of fishes (e.g., telemetry, population genetics, hydroacoustics, otolith microchemistry, stable isotope analysis), new knowledge can now be generated and incorporated into biological assessment and fishery management. For example, knowing when, where, and how to deploy assessment gears is essential to inform, refine, or calibrate assessment protocols. Such information is also useful for quantifying or avoiding bycatch of imperiled species. Knowledge of habitat connectivity and usage can identify critically important migration corridors and habitats and can be used to improve our understanding of variables that influence spatial structuring of fish populations. Similarly, demographic processes are partly driven by the behavior of fish and mediated by environmental drivers. Information on these processes is critical to the development and application of realistic population dynamics models. Collectively, biological assessment, when informed by knowledge of spatial ecology, can provide managers with the ability to understand how and when fish and their habitats may be exposed to different threats. Naturally, this knowledge helps to better evaluate or develop strategies to protect the long-term viability of fishery production. Failure to understand the spatial ecology of fishes and to incorporate spatiotemporal data can bias population assessments and forecasts and potentially lead to ineffective or counterproductive management actions. 相似文献
112.
Carolina Oliveira de Santana Taíse Bomfim de Jesus William Moura de Aguiar Washington de Jesus Sant’anna Franca-Rocha Carlos Alberto Caroso Soares 《Environmental monitoring and assessment》2017,189(3):123
In this study, an analysis was performed on the concentrations of the trace elements Al, As, Ba, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, V, and Zn in muscle of two carnivorous and one planktivorous fish species collected at Todos os Santos Bay (BTS). The accumulation order of the trace elements in Lutjanus analis was Al >Zn >Fe >Cr >Ba >Ni. In Cetengraulis edentulus, the order was Al >Fe >Zn >Cr >Ni >Mn >As. In the species Diapterus rhombeus, the order was Al >Fe >Zn >Cr >Ni >Mn >Cd. To determine the risk related to the consumption of fish, toxicity guidelines were used as standard references. It was observed that the species C. edentulus contained concentrations of As exceeding WHO limits, but these concentrations were acceptable according to the Agência Nacional de Vigilância Sanitária (ANVISA) guidelines. Cd levels were found only in D. rhombeus and in low concentrations according to the determinations of WHO and ANVISA. Pb levels were not detected in any of the three fish species. The analyzed elements did not differ statistically according to the species and feeding habits. The results point to possible risks of human contamination by As related to the consumption of the fish species C. edentulus from the BTS. 相似文献
113.
114.
Carlos Palacín Juan C. Alonso Carlos A. Martín Javier A. Alonso 《Conservation biology》2017,31(1):106-115
Many bird populations have recently changed their migratory behavior in response to alterations of the environment. We collected data over 16 years on male Great Bustards (Otis tarda), a species showing a partial migratory pattern (sedentary and migratory birds coexisting in the same breeding groups). We conducted population counts and radio tracked 180 individuals to examine differences in survival rates between migratory and sedentary individuals and evaluate possible effects of these differences on the migratory pattern of the population. Overall, 65% of individuals migrated and 35% did not. The average distance between breeding and postbreeding areas of migrant individuals was 89.9 km, and the longest average movement of sedentary males was 3.8 km. Breeding group and migration distance had no effect on survival. However, mortality of migrants was 2.4 to 3.5 times higher than mortality of sedentary birds. For marked males, collision with power lines was the main cause of death from unnatural causes (37.6% of all deaths), and migratory birds died in collisions with power lines more frequently than sedentary birds (21.3% vs 6.3%). The percentage of sedentary individuals increased from 17% in 1997 to 45% in 2012. These results were consistent with data collected from radio‐tracked individuals: The proportion of migratory individuals decreased from 86% in 1997–1999 to 44% in 2006–2010. The observed decrease in the migratory tendency was not related to climatic changes (temperatures did not change over the study period) or improvements in habitat quality (dry cereal farmland area decreased in the main study area). Our findings suggest that human‐induced mortality during migration may be an important factor shaping the migration patterns of species inhabiting humanized landscapes. 相似文献
115.
116.
During 2008 and 2009, an epidemic affected sponges of the genus Ircinia in the Western Mediterranean. Investigations at a site on the European coast (6o43′08.80′′N; 3o43′52.20′′W) and another on
the African coast (35o10′51.00′′N; 2o25′33.00′′W) revealed healthier African populations. The disease started with small pustules
on the sponge surface, which subsequently coalesced forming larger, extensive lesions. An ultrastructural study suggested
that a twisted rod is the etiological agent. It infected the sponges from the outside, initially killing the cells below the
ectosome and then penetrating deeper into the body. The sponges responded to the bacterial progression by secreting concentric
barriers of collagen and concentrating phagocytic cells at the diseased zones. This primitive immune system successfully resisted
the disease in many instances, although mortality reached 27% in the studied populations. Epidemic outbreaks recur each year
in September through November, arguably favored by abnormally high seawater temperatures in August. 相似文献
117.
Stefan Gelcich Miriam Fernández Natalio Godoy Antonio Canepa Luis Prado Juan Carlos Castilla 《Conservation biology》2012,26(6):1005-1015
Territorial user rights for fisheries have been advocated as a way to achieve sustainable resource management. However, few researchers have empirically assessed their potential as ancillary marine conservation instruments by comparing them to no‐take marine protected areas. In kelp (Lessonia trabeculata) forests of central Chile, we compared species richness, density, and biomass of macroinvertebrates and reef fishes among territorial‐user‐right areas with low‐level and high‐level enforcement, no‐take marine protected areas, and open‐access areas in 42 100‐m subtidal transects. We also assessed structural complexity of the kelp forest and substratum composition. Multivariate randomized permutation tests indicated macroinvertebrate and reef fish communities associated with the different access regimes differed significantly. Substratum composition and structural complexity of kelp forest did not differ among access regimes. Univariate analyses showed species richness, biomass, and density of macroinvertebrates and reef fishes were greater in highly enforced territorial‐user‐right areas and no‐take marine protected areas than in open‐access areas. Densities of macroinvertebrates and reef fishes of economic importance were not significantly different between highly enforced territorial‐user‐right and no‐take marine protected areas. Densities of economically important macroinvertebrates in areas with low‐level enforcement were significantly lower than those in areas with high‐level enforcement and no‐take marine protected areas but were significantly higher than in areas with open access. Territorial‐user‐right areas could be important ancillary conservation instruments if they are well enforced. Derechos de Usuario Territoriales para Pesquerías como Instrumentos Accesorios para la Conservación Marina Costera en Chile 相似文献
118.
Michael Kosusko Carlos M. Nunez 《Journal of the Air & Waste Management Association (1995)》2013,63(2):254-259
Catalytic oxidation is an air pollution control technique in which volatile organic compounds (VOCs) and vapor-phase air toxics in an air emission stream are oxidized with the help of a catalyst Design of catalytic systems for control of point source emissions is based on stream-specific characteristics and desired control efficiency. This paper discusses the key emission stream characteristics and VOC characteristics that affect the applicability of catalytic oxidation. The application of catalytic oxidation technology to four types of air emission sources is discussed: (1) groundwater stripping operations; (2) graphic arts facilities; (3) flexographic printing plants; and (4) latex monomer production. The characteristics of each of these emissions are discussed along with the catalytic technology used to control these emissions. 相似文献
119.
Recycled blocks with improved sound and fire insulation containing construction and demolition waste
Carlos Leiva Jaime Solís-Guzmán Madelyn Marrero Celia García Arenas 《Waste management (New York, N.Y.)》2013,33(3):663-671
The environmental problem posed by construction and demolition waste (C&D waste) is derived not only from the high volume produced, but also from its treatment and disposal. Treatment plants receive C&D waste which is then transformed into a recycled mixed aggregate. The byproduct is mainly used for low-value-added applications such as land escape restoration, despite the high quality of the aggregate. In the present work, the chemical composition properties and grading curve properties of these aggregates are defined. Furthermore, the resulting recycled concrete with a high proportion of recycled composition, from 20% to 100% replacement of fine and coarse aggregate, is characterized physically and mechanically. An environmental study of the new construction material when all aggregates are substituted by C&D waste shows a low toxicity level, similar to that of other construction materials. The new material also has improved properties with respect to standard concrete such as high fire resistance, good heat insulation, and acoustic insulation. 相似文献
120.
Species differ widely with regard to parental investment strategies and mechanisms underlying those strategies. The passing of benefits to likely offspring can be instantiated with a number of different computational and behavioral systems. We report results from an agent-based model in which offspring maintain proximity with parents and parents transmit benefits to offspring without the capacity of either parent or offspring to 'recognize' one another. Instead, parents follow a simple rule to emit benefits after reproducing and offspring follow a simple rule of moving in the direction of positive benefit gradients. This model differs from previous models of spatial kin-based altruism in that individuals are modeled as having different behavioral rules at different life stages and benefits are transmitted unidirectionally from parents to offspring. High rates of correctly directed parental investment occur when mobility and sociality are low and parental investment occurs over a short period of time. We suggest that strategies based on recognition and bonding/attachment might serve to increase rates of correctly directed parental investment under parameters that are shown here to otherwise lead to high rates of misdirected and wasted parental investment. 相似文献