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61.
Rouibah Ikram Hassen Wafa Sallem Ons Fekih Khellaf Nabila Hassen Abdennaceur Mansour Hedi Ben 《Environmental science and pollution research international》2021,28(12):14530-14545
Environmental Science and Pollution Research - Medicines and drugs consumption by all populations of the world can be expected to result in the contamination of the environment since 30–90%... 相似文献
62.
Alexander L. Metcalf Conor N. Phelan Cassandra Pallai Michael Norton Ben Yuhas James C. Finley Allyson Muth 《Conservation biology》2019,33(5):1141-1150
Widespread human action and behavior change is needed to achieve many conservation goals. Doing so at the requisite scale and pace will require the efficient delivery of outreach campaigns. Conservation gains will be greatest when efforts are directed toward places of high conservation value (or need) and tailored to critical actors. Recent strategic conservation planning has relied primarily on spatial assessments of biophysical attributes, largely ignoring the human dimensions. Elsewhere, marketers, political campaigns, and others use microtargeting—predictive analytics of big data—to identify people most likely to respond positively to particular messages or interventions. Conservationists have not yet widely capitalized on these techniques. To investigate the effectiveness of microtargeting to improve conservation, we developed a propensity model to predict restoration behavior among 203,645 private landowners in a 5,200,000 ha study area in the Chesapeake Bay Watershed (U.S.A.). To isolate the additional value microtargeting may offer beyond geospatial prioritization, we analyzed a new high-resolution land-cover data set and cadastral data to identify private owners of riparian areas needing restoration. Subsequently, we developed and evaluated a restoration propensity model based on a database of landowners who had conducted restoration in the past and those who had not (n = 4978). Model validation in a parallel database (n = 4989) showed owners with the highest scorers for propensity to conduct restoration (i.e., top decile) were over twice as likely as average landowners to have conducted restoration (135%). These results demonstrate that microtargeting techniques can dramatically increase the efficiency and efficacy of conservation programs, above and beyond the advances offered by biophysical prioritizations alone, as well as facilitate more robust research of many social–ecological systems. 相似文献
63.
An improved trend vegetation analysis for non-stationary NDVI time series based on wavelet transform
Rhif Manel Ben Abbes Ali Martinez Beatriz Farah Imed Riadh 《Environmental science and pollution research international》2021,28(34):46603-46613
Environmental Science and Pollution Research - The aim of this paper is to improve trend analysis for non-stationary Normalized Difference Vegetation Index (NDVI) time series (TS) over different... 相似文献
64.
65.
For nearly a century researchers have investigated the uptake and utilization of dissolved organic matter (DOM) by marine
invertebrates, but its contribution to their growth, reproduction, and survival remains unclear. Here, the benefit of DOM
uptake was assessed for the marine bryozoan Bugula neritina (Linnaeus 1758) through performance comparisons of individuals in the presence and absence of DOM. The experiments were performed
using B. neritina collected from floating docks in Beaufort, NC, USA from July to September 2004. Seawater was subjected to ultraviolet irradiation
to reduce naturally occurring DOM, and then enriched with either 1 μM of palmitic acid or a mixture containing 1 μM each of
glucose, alanine, aspartic acid and glycine. Larvae in DOM-enriched and DOM-reduced treatments were sampled and induced to
metamorphose following 1, 6, 12, and 24 h of continuous swimming at 25°C. Sampled larvae were assessed for initiation of metamorphosis,
completion of metamorphosis, and ancestrular lophophore size to determine the extent to which energy acquired from DOM uptake
could offset the metabolic costs of prolonged larval swimming. DOM treatment had no significant effect on initiation of metamorphosis,
but did have a significant effect on completion of metamorphosis and lophophore size. Larvae swimming in DOM-enriched treatments
for 24 h experienced a 20% increase in metamorphic completion rate, compared to larvae swimming for 24 h in the DOM-reduced
treatment. In addition, larvae in the amino acid and sugar mixture for 24 h had a significantly larger lophophore surface
area and volume (23 and 31%, respectively), compared to larvae in DOM-depleted seawater. To ensure that the increases in performance
found in larvae with access to DOM were not due to a decrease in metabolic activity, the respiration rates for these larvae
were compared to those of larvae in DOM-depleted seawater. There were no significant differences between these treatments,
indicating that the increases in performance were due to the energy acquired from DOM. These results clearly show that for
B. neritina, DOM uptake results in increased metamorphic success and in the size of the feeding apparatus following an extended larval
swimming duration. 相似文献
66.
D. Dean 《Marine Biology》1978,45(2):165-173
There have been many previous reports of the sandworm Nereis virens Sars swimming in the water column. This behavior usually has been attributed to reproductive processes. Sandworms were found swimming in surface waters at night on ebb tides during many nights of January, February and March in a Maine (USA) estuary. None of the specimens examined contained gametes or possessed other characteristic spawning or pre-spawning modifications. Several age classes were found, with worms measuring 9 to 38 cm in length, weighing 0.5 to 19.8 g, and having 82 to 187 segments. The greatest numbers of worms were observed during near-average tides on evenings in which low tides occurred a few hours after sunset but prior to moonrise. Up to 83 worms per minute were observed swimming seaward through a 20 m transect, while none were observed swimming landward at any stage of the tide. It is concluded that sandworms swimming during winter nights is unrelated to reproduction and that it is an inherent behavior pattern.Contribution No. 102 of the Ira C. Darling Center, Walpole, Maine 04573, USA. 相似文献
67.
The macro-algae communities observed in the south lake of Tunis are characterized by the predominance of nitrophilous algae
which are in the order of biomass importance:Ulva, Cladophora andEnteromorpha. We have noted seasonal changes of alga distribution. The wind appears to be one of the most important factors influencing
this distribution. The total biomass reaches a maximum in the spring. Rapid decomposition of the biomass leads to a severe
ecological imbalance, resulting in crises of anoxia and fish death.
A restoration project has already started. It aims at removal of contaminated muds and the introduction of a new circulation
system.
The main objectives of this work were to collect information on the distribution and biomass of the phytobenthic communities
as a first step in the constitution of a database for further comparison. 相似文献
68.
Lotfi Rabaoui Sabiha Tlig Zouari Stelios Katsanevakis Oum Kalthoum Ben Hassine 《Marine Biology》2007,152(3):537-548
The variability in absolute and relative growth of Pinna nobilis along the Tunisian coastline was investigated. Five populations of P. nobilis were sampled, three from northern and two from eastern Tunisia. The specimens were aged and ten morphometric characters were
measured on each individual. To test if differences existed in absolute and relative growth patterns among the different populations
an information theory approach was followed. For absolute growth, von Bertalanffy, Gompertz, the logistic and the power models
were fitted in combination with three assumptions regarding inter-population differences in absolute growth patterns: no differences,
differences among all five populations or just between northern and eastern populations. The assumption of common absolute
growth parameters among all five populations had the greatest support by the data, whereas the assumption of different growth
patterns among all five populations had no support. Von Bertalanffy growth model and the power model were both equally supported
by the data (while Gompertz had considerably less support and the logistic model had no support), and thus it may not be definitely
concluded whether P. nobilis grows asymptotically or not. The P. nobilis populations of the Tunisian coastline had a slow growth and up to an age of ∼ 9 years their shells were smaller than from
all other reported populations in the Mediterranean. For relative growth, apart from the classical allometric model Y = aX
b
, relating the size of a part of a body Y to another reference dimension X, more complicated models were used in combination with the three abovementioned assumptions regarding inter-population differences.
Those models, of the form logY = f (logX), either assumed breakpoints in the relative growth trajectories or non-linearities. For most morphometric characters, the
classical allometric model had no support by the data and more complicated models were necessary. In most cases, different
relative growth either among all five populations or between the northern and eastern population groups was supported by the
data. Further investigation is needed to relate the morphological differences observed among different populations of P. nobilis to environmental factors. 相似文献
69.
László Z. Garamszegi Thorsten J. S. Balsby Ben D. Bell Marta Borowiec Bruce E. Byers Tudor Draganoiu Marcel Eens Wolfgang Forstmeier Paolo Galeotti Diego Gil Leen Gorissen Poul Hansen Helene M. Lampe Stefan Leitner Jan Lontkowski Laurent Nagle Erwin Nemeth Rianne Pinxten Jean-Marc Rossi Nicola Saino Aurélie Tanvez Russell Titus János Török Els Van Duyse Anders P. Møller 《Behavioral ecology and sociobiology》2005,57(4):305-317
Repertoire size, the number of unique song or syllable types in the repertoire, is a widely used measure of song complexity in birds, but it is difficult to calculate this exactly in species with large repertoires. A new method of repertoire size estimation applies species richness estimation procedures from community ecology, but such capture-recapture approaches have not been much tested. Here, we establish standardized sampling schemes and estimation procedures using capture-recapture models for syllable repertoires from 18 bird species, and suggest how these may be used to tackle problems of repertoire estimation. Different models, with different assumptions regarding the heterogeneity of the use of syllable types, performed best for different species with different song organizations. For most species, models assuming heterogeneous probability of occurrence of syllables (so-called detection probability) were selected due to the presence of both rare and frequent syllables. Capture-recapture estimates of syllable repertoire size from our small sample did not differ significantly from previous estimates using larger samples of count data. However, the enumeration of syllables in 15 songs yielded significantly lower estimates than previous reports. Hence, heterogeneity in detection probability of syllables should be addressed when estimating repertoire size. This is neglected using simple enumeration procedures, but is taken into account when repertoire size is estimated by appropriate capture-recapture models adjusted for species-specific song organization characteristics. We suggest that such approaches, in combination with standardized sampling, should be applied in species with potentially large repertoire size. On the other hand, in species with small repertoire size and homogenous syllable usage, enumerations may be satisfactory. Although researchers often use repertoire size as a measure of song complexity, listeners to songs are unlikely to count entire repertoires and they may rely on other cues, such as syllable detection probability.Communicated by A. Cockburn 相似文献
70.
Sondes Melliti Ben Garali Inès Sahraoui Pablo de la Iglesia Mohamed Chalghaf Jorge Diogène Jamel Ksouri 《Chemistry and Ecology》2020,36(1):66-82
ABSTRACTThe seasonal variations in Pseudo-nitzschia species and domoic acid (DA) concentration were investigated, at three shellfish farms in SW coastal Mediterranean. In parallel, the toxicity of mussels was tested. Two distinct groups of species were enumerated according to morphology and size (Pseudo-nizschia delicatissima and P. seriata groups). DA was detected over a nine-week period from July to October 2012 in the Lagoon, with a maximum concentration recorded in July (12.71?ng?DA?L?1). DA was positively correlated with the presence of P. seriata-group and P. delicatissima-group and was mostly occurred during P limitation period in seawater. No DA was found in mussels that were collected during the period of DA absence in seawater. Our results suggest that temperature, salinity, inorganic and organic nutrients were significant for the seasonal dynamics of P. seriata and P. delicatissima groups, but that the P limitation was the most driving factor for DA production in these areas. The relative influence of environmental factors should be further studied to better understand the recent surfacing of massive blooms of toxigenic Pseudo-nitzschia in SW Mediterranean coast. 相似文献