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161.
Vilis Brukas Andrius Kuliešis Ola Sallnäs Edgaras Linkevičius 《Natural resources forum》2011,35(2):77-88
As tensions among diverse forest‐use interests in Lithuania are on the rise, this study examines the actual resource availability, the underlying planning approaches and the pertinent policy arena. Two 5‐year cycles of sampling‐based forest inventory provide accurate data showing that the overall timber harvest/increment ratio (or utilization intensity) is 61%. Utilization intensity is similar in state and private forests. It could potentially be raised to 70‐80%, with due account for environmental values. Such an increase is inhibited by rigid routines of forest management planning, involving inflexible rotation ages and cutting norms. Age‐class analysis indicates that the current planning practice counters its underlying aim of achieving a long‐term even flow of timber. According to a survey of key forest stakeholders, those who directly benefit from forest utilization have a weak position in the policy arena, the dominant powers being vested in the national forestry authorities. State forest enterprises have to follow restrictive plans from above, private forest owners are constrained by stern regulations and suffer from the bad image caused by the persistent myth of overuse in private forests. More rational management of Lithuanian forests is hardly possible without major shifts in the institutional set‐up accompanied by transformation of the professional ideology. 相似文献
162.
Exploitation of certain resources within a protected area on a sustainable basis could contribute to higher living standards
of rural people, particularly those in poor countries, and decrease conflicts between these populations and park authorities.
This article presents data from a case study of Kopaonik National Park (NP), Serbia, which is a park with natural resources,
most notably bilberries, which have always been relied on by local people. Vaccinium myrtillus traditionally has been collected for decades in Kopaonik NP and used by local people. However, little is known about the
socioeconomic and ecological relations that affect the collection and use of this species. The aim of the present study was
to understand how local people collect bilberries in Kopaonik NP and what their attitudes toward the park are. Household questionnaire
data were used to examine how local people collect bilberries and how to improve the relations between local people and NP
authorities. The survey questionnaire included 52 households from 7 local communities, and we applied a purposive sampling
strategy. In addition, expert interviews were conducted, and from these data we obtained a broader understanding of the relation
between local people and NP authorities. The results indicate that in Kopaonik NP, there is a conflict between pickers and
NP authorities. Sustainable management should be directed toward the protection of bilberries. Education of local people is
a key element in the sustainable collection and protection of natural resources. 相似文献
163.
John M. Logan Enrique Rodríguez-Marín Nicolas Goñi Santiago Barreiro Haritz Arrizabalaga Walter Golet Molly Lutcavage 《Marine Biology》2011,158(1):73-85
Atlantic bluefin tuna (Thunnus thynnus) are highly migratory predators whose abundance, distribution, and somatic condition have changed over the past decades.
Prey community composition and abundance have also varied in several foraging grounds. To better understand underlying food
webs and regional energy sources, we performed stomach content and stable isotope analyses on mainly juvenile (60–150 cm curved
fork length) bluefin tuna captured in foraging grounds in the western (Mid-Atlantic Bight) and eastern (Bay of Biscay) Atlantic
Ocean. In the Mid-Atlantic Bight, bluefin tuna diet was mainly sand lance (Ammodytes spp., 29% prey weight), consistent with historic findings. In the Bay of Biscay, krill (Meganyctiphanes norvegica) and anchovy (Engraulis encrasicolus) made up 39% prey weight, with relative consumption of each reflecting annual changes in prey abundance. Consumption of anchovies
apparently declined after the local collapse of this prey resource. In both regions, stable isotope analysis results showed
that juvenile bluefin tuna fed at a lower trophic position than indicated by stomach content analysis. In the Mid-Atlantic
Bight, stable isotope analyses suggested that >30% of the diet was prey from lower trophic levels that composed <10% of the
prey weights based upon traditional stomach content analyses. Trophic position was similar to juvenile fish sampled in the
NW Atlantic but lower than juveniles sampled in the Mediterranean Sea in previous studies. Our findings indicate that juvenile
bluefin tuna targeted a relatively small range of prey species and regional foraging patterns remained consistent over time
in the Mid-Atlantic Bight but changed in relation to local prey availability in the Bay of Biscay. 相似文献
164.
Matjaž Hriberšek Niko Samec Jure Ravnik Matej Zadravec 《Environmental Modeling and Assessment》2011,16(5):479-489
The contribution presents numerical simulation of gypsum particles, lifting from a gypsum landfill. First, particle characteristics
are presented, resulting from different technologies of gypsum depositing. Next, a laboratory experiment parameter validation
tests are described, which served as a means of determination of mass flow of particles from the landfill. The background
of the numerical simulations, used in the assessment of landfill impact on the environment, is also described. Simulations
consist of two parts: simulation of a long term impact of the particles on the surrounding area, performed by implementation
of the Gaussian dispersion model based computer code ISC3, and second, a CFD based simulation for assessing the flow and mass
concentration fields in the vicinity of the landfill for several pre-selected flow cases. The results of both computational
approaches are presented and compared. In the conclusions, a relation of the simulation results with existing environmental
pollution levels is made, and recommendations for landfill management are drawn. 相似文献
165.
Hanedar Asude Çifçi Deniz İzlen Zafer Nur Görgün Erdem 《Journal of Material Cycles and Waste Management》2022,24(5):1760-1767
Journal of Material Cycles and Waste Management - In this study, the amount of medical waste generated in a high-populated city in Turkey between January 2018 and August 2021 was evaluated, and the... 相似文献
166.
Matijaković Mlinarić Nives Selmani Atiđa Brkić Antun Lovro Njegić Džakula Branka Kralj Damir Kontrec Jasminka 《Environmental Chemistry Letters》2022,20(4):2235-2242
Environmental Chemistry Letters - Plastic pollution in water ecosystems is threatening the survival of wildlife. In particular, microplastics may be encapsulated into calcium carbonate, a crucial... 相似文献
167.
Environmental Modeling & Assessment - Lucas–Washburn equation is a fundamental expression which is used to describe capillary rise in porous materials according to average pore radius,... 相似文献
168.
In this study, we investigated the in vitro effects of metal ions on Mg2+-ATPase activity in isolated membranes from rat uterus. The effects of increasing concentrations of metal salts (CrCl2, CuSO4, HgCl2 and ZnSO4) show sigmoidal and almost complete inhibition relative to the control enzyme activity. According to the IC50, the ATPase possesses greater sensibility to
$ {\text{Zn}}^{{{\text{2}} + }} > {\text{Cu}}^{{{\text{2}} + }} \cong {\text{Cr}}^{{{\text{3}} + }} \cong {\text{Hg}}^{{{\text{2}} + }} ,$ {\text{Zn}}^{{{\text{2}} + }} > {\text{Cu}}^{{{\text{2}} + }} \cong {\text{Cr}}^{{{\text{3}} + }} \cong {\text{Hg}}^{{{\text{2}} + }} , while other metal salts exhibit the following inhibition: CdCl2 55%, CsCl 64.5% and SrCl2 58%. Here we demonstrated that the physico-chemical properties of these metals are of importance in defining possible mechanisms
of binding and decrease of enzyme activity. 相似文献
169.
M. Aničić M. Tasić M. V. Frontasyeva M. Tomašević S. Rajšić L. P. Strelkova A. Popović E. Steinnes 《Environmental Chemistry Letters》2009,7(1):55-60
Active biomonitoring of the air quality in Belgrade, Serbia, was performed using the moss Sphagnum
girgensohnii. Moss bags were exposed in parallel with and without irrigation for 3 and 6 months, respectively, at three different sites.
Twenty-nine elements were determined in the exposed moss samples by INAA. For all exposure periods, higher uptake in the irrigated
moss bags was evident for Al, Cr, Fe, Zn and Sr. Elements such as Cl, K, Rb and Cs were depleted in the moss tissue during
the time of exposure. For most of the elements the accumulation after 6 months exceeded that observed after 3 months. 相似文献
170.