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211.
Livia Poenaru Christine Mezard Said Akli Jean-François Oury Yves Dumez Joëlle Boue 《黑龙江环境通报》1990,10(4):231-235
We investigated the possibility of prenatal diagnosis of mucolipidosis type II (ML II) by lysosomal enzyme determination on amniotic fluid obtained at 11 weeks of gestation in three pregnancies at risk. Diagnosis of ML II was made in one case on the basis of increased levels of five lysosomal enzymes tested. The diagnosis was confirmed on cultured chorionic cells, their cultured medium, 17–week amniotic fluid, and fetal plasma obtained for confirmation prior to the termination of pregnancy. 相似文献
212.
Unicoloniality emerges as a feature that characterizes successful invasive species. Its underlying mechanism is reduced intraspecific aggression while keeping interspecific competitiveness. To that effect, we present here a comparative behavioural and chemical study of the invasive ant Wasmannia auropunctata in parts of its native and introduced ranges. We tested the hypothesis that introduced populations (New Caledonia archipelago) have reduced intraspecific aggression relative to native populations (e.g., Ilhéus area, Brazil) and that this correlates with reduced variability in cuticular hydrocarbons (CHCs). As predicted, there was high intraspecific aggression in the Brazilian populations, but no intraspecific aggression among the New Caledonian populations. However, New Caledonian worker W. auropunctata remained highly aggressive towards ants of other invasive species. The chemical data corresponded with the behaviour. While CHCs of ants from the regions of Brazil diverged, the profiles of ants from various localities in New Caledonia showed high uniformity. We suggest that in New Caledonia W. auropunctata appears to behave as a single supercolony, whereas in its native range it acts as a multicolonial species. The uniformity of recognition cues in the New Caledonia ants may reflect a process whereby recognition alleles became fixed in the population, but may also be the consequence of a single introduction event and subsequent aggressive invasion of the ecosystem. Chemical uniformity coupled with low intraspecific but high interspecific aggression, lend credence to the latter hypothesis. 相似文献
213.
Davidson CM Gibson MD Hamilton E MacGillivray BH Reglinski J Rezabal E 《Chemosphere》2005,58(6):793-798
The concentrations of strontium and barium have been measured in water, sediment and the shells of mussels (Mytilus edulis) from a river system in the Sunart region of Scotland, UK. The aim was to establish the fate and mobility of these elements, which are slowly being released from old mine workings on the Strontian granites. Enhanced strontium (1500-2000 microg l(-1) and 250-290 microg l(-1)) and barium concentrations (316 microg l(-1) and 83 microg l(-1)) were found in the waters originating from the two mine drains studied. Both element were also found at significant levels in the river sediments taken from the vicinity of each drainage site (Sr: 225 microg g(-1) and 120-125 microg g(-1); Ba: 1380 microg g(-1) and 126-170 microg g(-1)). The data suggests that the sediments are acting as a reservoir for these group II cations from where they become distributed throughout the river system. Strontium is found to be incorporated into the shells (3.16-3.46 microg g(-1)) and pearls (3.57 microg g(-1)) of the blue mussel, located at the estuarine margin some 10 km downstream, at values close to the maximum expected (3.3% by weight of the calcium content). The study presents a view of the fate of barium and strontium in a river system over a prolonged period of time. As such it provides valuable information for studies that seek to model the impact of the accidental release of barium and strontium (including the important radionuclide 90Sr) into the environment. 相似文献
214.
Hans-Joachim Ballach Christine Niederée Rüdiger Wittig Ernst J. Woltering 《Environmental science and pollution research international》1995,2(4):201-206
Ozone-induced changes in ethylene production, ACC oxidase activity and the contents of ACC, MACC and free PAs were studied inPopulus nigra L. cv. Loenen with high ozone sensitivity as judged by the degree of chlorophyll degradation and premature leaf abscission. Ethylene production, ACC oxidase activity, ACC content and MACC levels were induced by the one-, two-, and three-week ozone exposure (36±9 ppb O3 for 11 hours a day). In addition, increases in PA levels, especially in spermidine, were measured in ozone treated plants. The role of free PAs and MACC synthesis as possible antisenescence reactions is discussed. 相似文献
215.
Christine Throl 《Umweltwissenschaften und Schadstoff-Forschung》2000,12(3):137-147
Zusammenfassung
Hintergrund Im Rahmen von Mess- und Monitoringprogammen werden Stoffkonzentrationen in B?den gemessen. Diese Daten müssen auch in Hinblick
auf die Auswirkungen auf terrestrische Bioz?nosen beurteilt werden. Ma?st?be zur Beurteilung gab es bisher jedoch nicht. Diese
Lücke wurde nun durch die Vorlage eines Konzepts zur Ableitung von ?kotoxikologisch begründeten Bodenqualit?tskriterien (BQK)
und dessen Anwendung für umweltrelevante Stoffe geschlossen.
Schwerpunkte Das Konzept wurde für Arsen angewendet. Hier ist der Ableitungsprozess im Detail beschrieben, von der Ethebung der Wirkungsdaten
für mikrobiologische Prozesse, Pflanzen und Bodeninvertebraten bis hin zu einem Vorschlag eines BQK für Arsen.
Methoden Der konzeptionelle Ansatz für die Ableitung von BQK wurde, nach Auswertung von nationalen und internationalen Konzepten zur
Bewertung von Substanzen auf terrestrische Lebensgemeinschaften, erarbeitet. Für die Bewerttung von Arsen wurden alle relevanten
biotischen Prozesse und Trophieebenen berücksichtigt. Desweiteren wurden Bodeneigenschaften, die einen modifizierenden Einfluss
auf die Toxizit?t von Arsen auf Biota haben, aus den vorliegenden Studien erfasst.
Ergebnisse Die Bewertung der Wirkungen von Arsen für terrestrische Lebenegemeinschaften zeigt, dass ?kotoxikologische Wirkungswerte im
Bereich der Hintergrundwerte für B?den liegen k?nnen. Indes sind Studien, in denen der Einflus von Bodeneigenschaften wie
Boden-pH, Bodentextur untersucht wurde, nur in sehr geringer Anzahl vorhanden. Daher warde das ?kotoxikologische Bodenqualit?tskriterium
für Arsen, mit 5 mg/kg Boden TG, an Hintergrundwerten für sandige B?den orientiert (“Worst-Case”). Ein Vergleich der Ergebnisse
mit ?kotoxikologisch begründeten Bodenqualit?tswerten aus Kanada, D?nemark, den Niederlanden und den Vereinigten Staaten zeigt,
dass Werte für Arsen im Mittel bei nahezu 16 mg/kg Boden TG mit einer Spannweite von 5 bis 34 mg/kg liegen. Die Unterschiede
zwischen den Werten sind ma?geblich durch die unterschiedlichen konzeptionellen Ans?tze zur Ableitung der Bodenqualit?tswerte
begründet.
Schlussfolgerungen und Ausblick Hinsichtlich direkter Wirkungen von Stoffen in B?den wird das erarbeitete Konzept für die Ableitung von BQK zum Schutz terrestrischer
Lebengemeinschaften als geeignet angesehen. Daher soll es für weitere umweltrelevante Stoffe angewendet werden. Ebenso, ist
die Bewertung der indirekten Wirkungen von Bodenschadstoffen auf V?gel und S?ugetiere, die sich von Bodeninvertebraten ern?hren,
notwendig. Auch sollen, neben Ausgleichsfaktoren zum Risikoausgleich, statistischprobabilistische Verfahren in Betracht gezogen
werden.
Online-First: 8. Mai 2000 相似文献
216.
We used population models to explore the effects of the organochlorine contaminant p,p'-DDE and fluctuations in vole availability on the population dynamics of Burrowing Owls (Athene cunicularia). Previous work indicated an interaction between low biomass of voles in the diet and moderate levels of p,p'-DDE in Burrowing Owl eggs that led to reproductive impairment. We constructed periodic and stochastic matrix models that incorporated three vole population states observed in the field: average, peak, and crash years. We modeled varying frequencies of vole crash years and a range of impairment of owl demographic rates in vole crash years. Vole availability had a greater impact on owl population growth rate than did reproductive impairment if vole populations peaked and crashed frequently. However, this difference disappeared as the frequency of vole crash years declined to once per decade. Fecundity, the demographic rate most affected by p,p'-DDE, had less impact on population growth rate than adult or juvenile survival. A life table response experiment of time-invariant matrices for average, peak, and crash vole conditions showed that low population growth under vole crash conditions was due to low adult and juvenile survival rates, whereas the extremely high population growth under vole peak conditions was due to increased fecundity. Our results suggest that even simple models can provide useful insights into complex ecological interactions. This is particularly valuable when temporal or spatial scales preclude manipulative experimental work in the field or laboratory. 相似文献
217.
Ana M. M. Viana Anne Frézard Christian Malosse Terezinha M. C. Della Lucia Christine Errard Alain Lenoir 《Chemoecology》2001,11(1):29-36
Summary. Leaf cutting ants live in symbiosis with a basidiomycete fungus that is exploited as a source of nutrients for the ant larvae.
Tests of fungus transport demonstrated that Acromyrmex subterraneus subterraneus workers discriminate concolonial fungus from alien fungus, and rejected the latter. Larvae and pupae of the ant were used
as controls. Chemical analysis of the fungus revealed a great similarity between its hydrocarbon profile and that found on
the ant brood. Experiments with lures showed that chemical extracts from the fungus are responsible for this discrimination
process. Moreover, the presence of brood inside the fungus seemed to be important for discrimination of the fungus by workers.
Resident workers accepted concolonial broodless fungus less than concolonial fungus inoculated with brood odor. Fungus seems
to acquire colonial odor passively, simply by contact with the brood. The impact of fungus volume present in the nest on closure
of the colony is discussed. We show here for the first time the importance of a symbiotic vegetal organism in colonial recognition
in social insects.
Received 14 April 2000; accepted 29 September 2000 相似文献
218.
Andrew S. Cohen Roger Bills Christine Z. Cocquyt A.G. Caljon 《Conservation biology》1993,7(3):667-677
219.
Freddie-Jeanne Richard Michael Poulsen Abraham Hefetz Christine Errard David R. Nash Jacobus J. Boomsma 《Behavioral ecology and sociobiology》2007,61(11):1637-1649
Cuticular hydrocarbon profiles are essential for nestmate recognition in insect societies, and quantitative variation in these
recognition cues is both environmentally and genetically determined. Environmental cues are normally derived from food or
nest material, but an exceptional situation may exist in the fungus-growing ants where the symbiotic fungus garden may be
an independent source of recognition compounds. To investigate this hypothesis, we quantified the chemical profiles of the
fungal symbionts of 18 sympatric colonies of Acromyrmex echinatior and Acromyrmex octospinosus and evaluated the quantitative variation of the 47 compounds in a multivariate analysis. Colony-specific chemical profiles
of fungal symbionts were highly distinct and significantly different between the two ant species. We also estimated the relative
genetic distances between the fungal symbionts using amplified fragment length polymorphism (AFLP) and correlated these with
the overall (Mahalanobis) chemical distances between the colony-specific profiles. Despite the standardized laboratory conditions,
the correlations were generally weak, but a statistically significant portion of the total variation in chemical profiles
could be explained by genetic differences between the fungal symbionts. However, there was no significant effect of ant species
in partial analyses because genetic differences between symbionts tend to coincide with being reared by different ant species.
However, compound groups differed significantly with amides, aldehydes, and methyl esters contributing to the correlations,
but acetates, alkanes, and formates being unrelated to genetic variation among symbionts. We show experimentally that workers
that are previously exposed to and fed with the fungal symbiont of another colony are met with less aggression when they are
later introduced into that colony. It appears, therefore, that fungus gardens are an independent and significant source of
chemical compounds, potentially contributing a richer and more abundant blend of recognition cues to the colony “gestalt”
than the innate chemical profile of the ants alone.
Freddie-Jeanne Richard and Michael Poulsen contributed equally to this work. 相似文献
220.
Anne Bousquet-Mélou Sophie Louis Christine Robles Stéphane Greff Sylvie Dupouyet Catherine Fernandez 《Chemoecology》2005,15(4):193-198
Summary. Biological invasions are nowadays a major problem in ecology. Allelopathy has been shown to be involved in such invasions,
but this mechanism has been little studied in France. The objectives of this study were to evaluate the allelopathic potential
of Medicago arborea, an invasive species in the French Mediterranean region. Foliar extracts were tested on three target species (Lactuca sativa, Lepidium sativum and Linum strictum). We showed that Medicago arborea has high allelopathic potential to affect the growth and germination of other species. Yellow flax (Linum strictum), native to the invaded area, was the most sensitive of the tested plant species to foliar extracts of Medicago arborea. Our study pointed out the role of allelopathy in processes leading to biological invasion, and more generally in population
dynamics. 相似文献