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271.
A novel application of cultural consensus models to evaluate conservation education programs
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K.A.I. Nekaris Sharon McCabe Denise Spaan Muhammad Imron Ali Vincent Nijman 《Conservation biology》2018,32(2):466-476
Conservation professionals recognize the need to evaluate education initiatives with a flexible approach that is culturally appropriate. Cultural‐consensus theory (CCT) provides a framework for measuring the extent to which beliefs are communally held and has long been applied by social scientists. In a conservation‐education context, we applied CCT and used free lists (i.e., a list of items on a topic stated in order of cultural importance) and domain analysis (analysis of how free lists go together within a cultural group) to evaluate a conservation education program in which we used a children's picture book to increase knowledge about and empathy for a critically endangered mammal, the Javan slow loris (Nycticebus javanicus). We extracted free lists of keywords generated by students (n = 580 in 18 schools) from essays they wrote before and after the education program. In 2 classroom sessions conducted approximately 18 weeks apart, we asked students to write an essay about their knowledge of the target species and then presented a book and several activities about slow loris ecology. Prior to the second session, we asked students to write a second essay. We generated free lists from both essays, quantified salience of terms used, and conducted minimal residuals factor analysis to determine presence of cultural domains surrounding slow lorises in each session. Students increased their use of words accurately associated with slow loris ecology and conservation from 43% in initial essays to 76% in final essays. Domain coherence increased from 22% to 47% across schools. Fifteen factors contributed to the domain slow loris. Between the first and second essays, factors that showed the greatest change were feeding ecology and slow loris as a forest protector, which increased 7‐fold, and the humancentric factor, which decreased 5‐fold. As demonstrated by knowledge retention and creation of unique stories and conservation opinions, children achieved all six levels of Bloom's taxonomy of learning domains. Free from the constraints of questionnaires and surveys, CCT methods provide a promising avenue to evaluate conservation education programs. 相似文献
272.
Butler DM Ranells NN Franklin DH Poore MH Green JT 《Journal of environmental quality》2007,36(1):155-162
Maintaining ground cover of forages may reduce the export of nitrogen (N) from pastures. The objective of this work was to determine the effect of ground cover on N export from pastured riparian areas receiving simulated rainfall. Plots were established on two adjacent sites in the North Carolina Piedmont: one of 10% slope with Appling sandy loam soils and a second of 20% slope with Wedowee sandy loam soils. Both sites had existing mixed tall fescue (Festuca arundinacea Schreb.)-dallisgrass (Paspalum dilatatum Poir.) vegetation. Forage stands were modified to represent a range of ground cover levels: 0, 45, 70, and 95% (bare ground, low, medium, and high cover, respectively), and amended with beef steer (Bos taurus) feces and urine (approximately 200 kg N ha-1). For all rain events combined, mean nitrate N export was greatest from bare ground and was reduced by 34% at low cover, which did not differ from high cover. Mean ammonium N export was slightly elevated (approximately 1.37 kg N ha-1) in months when manures were applied and negligible (<0.02 kg N ha-1) in all other months. For all rain events combined, mean export of total N was greatest from bare ground and was reduced by at least 85% at all other cover levels. Whereas site did not impact N export, results indicated that cover and time of rainfall following manure deposition are important determinants of the impact of riparian grazing. 相似文献
273.
The objectives of this study were to compare the types and levels of volatile methyl siloxanes (VMS) present in biogas generated in the anaerobic digesters and landfills, evaluate the energetics of siloxane transformations under anaerobic conditions, compare the conditions in anaerobic digesters and municipal solid waste (MSW) landfills which result in differences in siloxane compositions. Biogas samples were collected at the South District Wastewater Treatment Plant and South Dade Landfill in Miami, Florida. In the digester gas, D4 and D5 comprised the bulk of total siloxanes (62% and 27%, respectively) whereas in the landfill gas, the bulk of siloxanes were trimethylsilanol (TMSOH) (58%) followed by D4 (17%). Presence of high levels of TMSOH in the landfill gas indicates that methane utilization may be a possible reaction mechanism for TMSOH formation. The free energy change for transformation of D5 and D4 to TMSOH either by hydrogen or methane utilization are thermodynamically favorable. Either hydrogen or methane should be present at relatively high concentrations for TMSOH formation which explains the high levels present in the landfill gas. The high bond energy and bond distance of the Si–O bond, in view of the atomic sizes of Si and O atoms, indicate that Si atoms can provide a barrier, making it difficult to break the Si–O bonds especially for molecules with specific geometric configurations such as D4 and D5 where oxygen atoms are positioned inside the frame formed by the large Si atoms which are surrounded by the methyl groups. 相似文献
274.
当主流商学院开始将更多的企业社会责任(CSR)话题带入教室时,一些教育家仍认为这些机构的努力不够。他们相信,现在所需要的,是围绕可持续发展概念来确定MBA教学大纲,大纲仍然讲授基础科目,但要染上绿色。 相似文献
275.
Renae J. Brodie Richard Styles Stephen Borgianini Jenice Godley Khayree Butler 《Marine Biology》2007,152(6):1283-1291
Dense populations of the fiddler crab Uca minax (Le Conte 1855) are common along tidally influenced freshwater rivers and streams >50 km from the sea. Adults do not migrate
from inland sites to release larvae, but instead release them directly into an environment where the zoeae cannot survive.
Laboratory salinity tolerance experiments were used to determine how long larvae from the inland-most population of U. minax along the Pee Dee River, South Carolina, USA can survive zero salinity compared to larvae from a brackish water population
(salinity 5) near the mouth of Winyah Bay in the same estuary. Larvae from the brackish water population were also exposed
to a salinity of 5 and their survival tracked. These experiments were conducted from May to August 2004 and 2005. To determine
if inland larvae suffered significant mortality in transit due to salinity stress, current profiles were measured in the field
and used to model the time taken by a larva using ebb-tide transport to travel to permissive salinities. The laboratory tolerance
experiments showed that larvae from the inland freshwater population had LT50’s of 4–5 days at 0 salinity, which were significantly
longer than those of the brackish water zoeae (2–3 days). Zoeae from the brackish water population survived for at least one
larval molt at a salinity of 5 with LT 50’s of ∼12 days. Estimated travel times to reach permissive salinities from the inland-most
population based on current profiles were 3–5 days for larvae using night-time only ebb-tide transport and 1.5–2.5 days for
those using ebb-tide transport both day and night. Previously published field data indicate that U. minax larvae do use both day- and night-time ebb-tide transport, and are found in high densities in the water column during the
day. These results lead to the conclusion that U. minax stage I zoeae do not undergo significant salinity-induced mortality during their 50+ km trip to the sea. 相似文献
276.
Field observations and model-presentation experiments have shown that yellow warblers (Dendroica petechia) produce seet calls preferentially in response to brood-parasitic brown-headed cowbirds (Molothrus ater). In this study, we investigated whether seet calls are functionally referential alarm calls denoting cowbirds by determining whether female warblers responded appropriately to seet calls in the absence of a cowbird, whether alarm calling by warblers varied with response urgency, and how warblers in a population allopatric with cowbirds responded to cowbird and avian predator models and seet playbacks. As a control, we presented chip calls, which are elicited by nest predators as well as by non-threatening intruders, but are not strongly associated with cowbirds. Yellow warblers responded differently to playbacks of seet than chip calls. To seet playbacks, almost 60% of females gave seet calls and rushed to sit in their nests, responses typically elicited by cowbirds, whereas these responses were given infrequently in response to chip calls. Yellow warblers seet called equally in situations that simulated low, medium and high risk of parasitism, which suggests that these calls did not vary with response urgency. In a population allopatric with cowbirds, seet calls were rarely produced in response to cowbird or avian nest predator models and never to seet playbacks. These results suggest that seet calls are functionally referential signals denoting cowbirds and that cowbird parasitism was a strong selective pressure in the evolution of functional referentiality in the seet call of yellow warblers.Communicated by W.A. Searcy 相似文献
277.
Testis size variation in frogs: testing the alternatives 总被引:1,自引:0,他引:1
Sharon B. Emerson 《Behavioral ecology and sociobiology》1997,41(4):227-235
While sperm competition may be a major factor affecting relative testis size in vertebrates as a whole, additional hypotheses
have not been given much attention in frogs. This is important because sperm competition is relatively uncommon in frogs and
relative testis size varies in frogs that do not have multiple-male breeding systems. This paper tests two additional hypotheses
for differences in relative testis size among frogs: relative clutch size (number of eggs/snout vent length) and androgen
level. Testis size was measured in 90 species of frogs belonging to five families. Relative testis size was found to be positively
correlated with relative clutch size in species that lack sperm competition. Mean androgen levels of species also positively
covaried with relative testis size. However, there was no correlation between relative testis size and level of male agonistic
behavior among species, despite other work indicating that testosterone levels are positively correlated with agonistic behavior
in at least some species. These findings suggest that a number of factors in addition to sperm competition are important in
the evolution of testis size in male frogs.
Received: 17 January 1997 / Accepted after revision: 23 June 1997 相似文献
278.
Copper-tolerant strains of the marine fouling alga Ectocarpus siliculosus (Dillw) Lyngb. have been recorded. The mechanisms of tolerance which may operate in a copper-tolerant strain were investigated by comparing the growth characteristics, copper content and extracellular organic production of tolerant and non-tolerant strains. Growth was measured by a wet-weight method. The copper content of dryashed cells was measured spectrophotometrically using tetraethylthiuram disulphide. The extracellular material is ultra-violet absorbing, and the production was measured by recording absorption at 265 nm. Evidence suggests that an exclusion mechanism is operating in the tolerant strain under investigation. The extracellular material, the cell wall or an associated organism make little or no contribution no this exclusion. Membrane and intracellular changes are believed to account for the tolerance in this strain of E. siliculosus. 相似文献
279.
280.
D.W. Davis E.M. McDougall D.L. Hendrix T.L. Steele J.E. Adaskaveg E.E. Butler 《Journal of the Air & Waste Management Association (1995)》2013,63(8):1116-1121
Unusual air particulates are linked to recent heavy infestations of the ash whitefly in California using high-performance liquid chromatography, scanning electron microscopy, optical and infrared microscopy, ion chromatography and X-ray fluorescence spectrometry. The unusual particles apparently are microdroplets of ash whitefly honeydew. Most of the suspended honeydew is in microdroplets with diameters between about two and twenty microns. The microdroplets were found to contain substantial amounts of sugars, primarily the oligosaccharides stachyose and raffinose. They also contain about 1 percent potassium, mainly as K+ The unusual microdroplets have been found in samples of air particulates taken in many areas of California after 1988. Using a receptor model, the suspended honeydew was calculated to add as much as 40 microgm/M3 to PM10 mass. The highest levels of suspended honeydew occurred between late August and early November. 相似文献