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71.
Enhancing Conservation,Ecosystem Services,and Local Livelihoods through a Wildlife Premium Mechanism
Eric Dinerstein Keshav Varma Eric Wikramanayake George Powell Susan Lumpkin Robin Naidoo Mike Korchinsky Christian Del Valle Shubash Lohani John Seidensticker Dirk Joldersma Thomas Lovejoy Andrey Kushlin 《Conservation biology》2013,27(1):14-23
We propose the wildlife premium mechanism as an innovation to conserve endangered large vertebrates. The performance‐based payment scheme would allow stakeholders in lower‐income countries to generate revenue by recovering and maintaining threatened fauna that can also serve as umbrella species (i.e., species whose protection benefits other species with which they co‐occur). There are 3 possible options for applying the premium: option 1, embed premiums in a carbon payment; option 2, link premiums to a related carbon payment, but as independent and legally separate transactions; option 3, link premiums to noncarbon payments for conserving ecosystem services (PES). Each option presents advantages, such as incentive payments to improve livelihoods of rural poor who reside in or near areas harboring umbrella species, and challenges, such as the establishment of a subnational carbon credit scheme. In Kenya, Peru, and Nepal pilot premium projects are now underway or being finalized that largely follow option 1. The Kasigau (Kenya) project is the first voluntary carbon credit project to win approval from the 2 leading groups sanctioning such protocols and has already sold carbon credits totaling over $1.2 million since June 2011. A portion of the earnings is divided among community landowners and projects that support community members and has added over 350 jobs to the local economy. All 3 projects involve extensive community management because they occur on lands where locals hold the title or have a long‐term lease from the government. The monitoring, reporting, and verification required to make premium payments credible to investors include transparent methods for collecting data on key indices by trained community members and verification of their reporting by a biologist. A wildlife premium readiness fund would enable expansion of pilot programs needed to test options beyond those presented here. Mejora de la Conservación, Servicios del Ecosistema y Calidad de Vida Local Mediante un Mecanismo de Compensación de Vida Silvestre 相似文献
72.
73.
Alexander?V.?EreskovskyEmail author Elizaveta?Gonobobleva Andrey?Vishnyakov 《Marine Biology》2005,146(5):869-875
All stages of vertical transmission of symbiotic bacteria, from the penetration into oocytes to the formation of rhagon, were investigated in the White Sea (Arctic) representatives of Halisarca dujardini Johnston (Demospongiae). Small populations of free-living specific symbiotic bacteria inhabit the mesohyl of H. dujardini. They are represented by a single morphotype of small spiral gram-positive bacteria. Vertical transmission of symbiotic bacteria between generations in sponges may occur in different ways. In the case of H. dujardini the bacteria penetrate into growing oocytes by endocytosis. A part of the bacteria plays a trophic role for oocytes and the other part remains undigested in membrane-bound vacuoles within the cytoplasm. In cleaving embryos bacteria are situated between the blastomeres or in the vacuoles. In the blastula all bacteria are disposed in the blastocoel. The symbionts are situated in intercellular spaces in free-swimming larvae and during metamorphosis. Symbiotic bacteria do not play any trophic role in the period of embryonic and postembryonic development of H. dujardini. No signs of destruction and digestion of bacteria were revealed at any stage of development.Communicated by O. Kinne, Oldendorf/Luhe 相似文献
74.
Saison C Perrin-Ganier C Schiavon M Morel JL 《Environmental pollution (Barking, Essex : 1987)》2004,130(2):275-285
This study examined the effect of regular tillage and cropping on the dissipation rate of PAHs in contaminated soil. Lysimeters were placed under natural climatic conditions for 2 years and designed to measure the concentration of PAHs in soil and leachates and their toxicity. The soil initially contained 2077 microg PAHs g(-1). The largest decrease in PAHs concentration occurred during the first 6 months. No further significant decrease was observed after this time. The surface soil layer always contained significantly less PAHs than the deeper layer, regardless of the treatments. Less than 8.4 x 10(-8)% of the PAH initially present in the soil (e.g. less or equal to 33 microg PAHs per lysimeter) were leached from the soils during the experiment and the leachates presented no toxicity (as measured by the Microtox test). The toxicity of the soils decreased with time and was significantly lower on the cropped soil compared to the other treatments, despite the residual concentration of PAHs being the highest in this soil. This study demonstrated that the dissipation rates of PAHs were slow after using natural attenuation even when tillage and cropping were performed at the soil surface. 相似文献
75.
Two dynamic flux chambers for direct measurement of odorous compound emissions from quiescent liquid surfaces were investigated under simulated conditions in the laboratory. Initially, a flux chamber built according to the model recommended by French standard NF X 43-104 was studied. This chamber was used in two different ways. The first led to a lack of precision concerning emissions rates from the sampled liquid surface, whereas the second led to an overestimation of the measurements. The second part of the study was devoted to an improved dynamic flux chamber, built according to the feedback from the results obtained using the normalised sampling system. Laboratory tests showed good accuracy and precision. This work underlines the importance of the aerodynamic performances of a dynamic sampling system. 相似文献
76.
Successful migration for passerine birds depends largely on the quality of stopover habitats, but we still lack complete knowledge
of how migrants search for habitats en route and how they behave when landing at poor quality stopover sites. We compared
the distance of exploratory movements and stopover durations of the reed warbler Acrocephalus scirpaceus, a reedbed habitat specialist, released at suitable (reed bed) and unsuitable (sand dune) stopover sites. Birds tape-lured
during nocturnal migration to a sand dune were captured, radio-tagged, released and tracked at two sites of contrasting habitat
quality. Lean birds were found to move further in the dunes (max. 300 m) than in reeds (max. 200 m), whereas ‘fat’ individuals
at both sites remained stationary. Birds spent just 1 day in the dunes and up to 13 days in the reeds. Our results suggest
that some nocturnal migrants with restricted diurnal exploratory movements depend on stopover site selection when ceasing
nocturnal flight. 相似文献
77.
Julio César Marín Leal Stanislas Dubois Francis Orvain Robert Galois Jean-Louis Blin Michel Ropert Marie-Paule Bataillé Alain Ourry Sébastien Lefebvre 《Marine Biology》2008,153(4):673-688
Food sources for cultivated marine bivalves generally are not well identified, although they are essential for a better understanding
of coastal ecosystems and for the sustainability of shellfish farming activities. In addition to phytoplankton, other organic
matter sources (OMS), such as microphytobenthos and detritus (of terrestrial or marine origins), can contribute significantly
to the growth of marine bivalves. The aim of this study was to identify the potential food sources and to estimate their contributions
to the growth of the Pacific oyster (Crassostrea gigas) in two contrasting trophic environments of Normandy (France): the Baie des Veys (BDV) and the Lingreville area (LIN). Two
sites were studied in the BDV area (BDV-S and BDV-N) and one in the LIN area. To estimate the contribution of each type of
OMS, we used a combination of stable natural isotope composition (δ13C, δ15N) analysis of OMS and oyster tissue together with a modelling exercise. Field sampling was conducted every 2 months over
1 year. The sampled sources were suspended particulate organic matter from marine (PhyOM) and terrestrial (TOM) origins, microphytobenthos
(MPB), detrital organic matter from the superficial sediment (SOM), and macroalgae (Ulva sp., ULV). A statistical mixing model coupled to a bioenergetic model was used to calculate the contributions of each different
source at different seasons. Results showed that isotopic composition of the animal flesh varied with respect to the potential
OMS over the year within each ecosystem. Significant differences were also observed among the three locations. For instance,
the δ13C and δ15N values of the oysters ranged from −20.0 to −19.1‰ and from 6.9 to 10.8‰ at BDV-S, from −19.4 to −18.1‰ and from 6.4 to 10.0‰
at BDV-N, and from −21.8 to −19.4‰ and from 6.3 to 8.3‰ at LIN. The contributions of the different sources to oyster growth
differed depending on the ecosystem and on the period of the year. Phytoplankton (PhyOM) predominated as the principal food
source for oysters (particularly in the LIN location). MPB, TOM, and ULV detritus also possibly contributed to oysters’ diet
during summer and autumn at the BDV-S and BDV-N sites. SOM was not considered an OMS because it was already a mix of the other
four OMS, but rather a trophic reservoir that potentially mirrored the trophic functioning of marine ecosystems. 相似文献
78.
Symbiotic bacteria from six Oscarella species (adults and embryos) collected in the Mediterranean Sea (O. lobularis, O. tuberculata, O. imperialis, O. microlobata, O. viridis) and the Sea of Japan (O. malakhovi) were investigated by scanning electron microscopy and transmission electron microscopy. In most cases, symbionts are rather
numerous. Each sponge species has a definite set of bacterial morphological types. All bacteria are extracellular. Symbionts
occupy the mesohyl of adult sponges or intercellular space in embryos and are often in contact with mesohylar filaments or
cells. Bacteria of some morphotypes have characteristic blebs. Most symbionts are gram-negative, and two types of bacteria
have traits of Archaea and one type of bacteria is similar to Planctomycetes. Data on morphology of bacterial symbionts can
be a good additional character for identification of Oscarella species, which have no skeleton. 相似文献
79.
Narimane Dorey Frank Melzner Sophie Martin François Oberhänsli Jean-Louis Teyssié Paco Bustamante Jean-Pierre Gattuso Thomas Lacoue-Labarthe 《Marine Biology》2013,160(8):2007-2022
This study investigated the effects of seawater pH (i.e., 8.10, 7.85 and 7.60) and temperature (16 and 19 °C) on (a) the abiotic conditions in the fluid surrounding the embryo (viz. the perivitelline fluid), (b) growth, development and (c) cuttlebone calcification of embryonic and juvenile stages of the cephalopod Sepia officinalis. Egg swelling increased in response to acidification or warming, leading to an increase in egg surface while the interactive effects suggested a limited plasticity of the swelling modulation. Embryos experienced elevated pCO2 conditions in the perivitelline fluid (>3-fold higher pCO2 than that of ambient seawater), rendering the medium under-saturated even under ambient conditions. The growth of both embryos and juveniles was unaffected by pH, whereas 45Ca incorporation in cuttlebone increased significantly with decreasing pH at both temperatures. This phenomenon of hypercalcification is limited to only a number of animals but does not guarantee functional performance and calls for better mechanistic understanding of calcification processes. 相似文献
80.