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101.
Culturomic tools enable the exploration of trends in human–nature interactions, although they entail inherent biases and necessitate careful validation. Furthermore, people may engage with nature across different culturomic data sets differently. We evaluated people's digital interest and engagement with plant species based on Wikipedia and Google data and explored the conservation implications of these temporal interest patterns. As a case study, we explored the digital footprints of the most popular plant species in Israel. We analyzed 4 years of daily page views from Hebrew Wikipedia and 10 years of daily Google search volume in Israel. We modeled popularity of plant species in these 2 data sets based on a suite of plant attributes. We further explored the seasonal trends of people's interest in each species. We found differences in how people interacted digitally with plants in Wikipedia and Google. Overall, in Google, searches for species that have utility to humans were more common, whereas in Wikipedia, plants that serve as cultural emblems received more attention. Furthermore, in Google, popular species attracted more attention over time, opposite to the trend in Wikipedia. In Google, interest in species with short bloom duration exhibited more pronounced seasonal patterns, whereas in Wikipedia, seasonality of interest increased as bloom duration increased. Together, our results suggest that people's digital interactions with nature may be inherently different depending on the sources explored, which may affect use of this information for conservation. Although culturomics holds much promise, better understanding of its underpinnings is important when translating insights into conservation actions. 相似文献
102.
Dynamical models usually assume that predation occurs between mature stages and/or between mature and immature stages. In this work a stage-structured discrete time model is developed for a system where intraguild predation takes place only in the course of immature stages of predator and its prey. Therefore, the proposed mathematical setup demands functional relations linking predation in immature life stages with survival and fecundity in mature stages. The behavior of the model is examined in order to investigate the interplay among predator attack rate, its satiation of prey consumption and the success of intraguild predator invasion. 相似文献
103.
The spatial pattern of the different species in complex ecosystems reflects the underlying ecological processes. In this paper a second order moment function is proposed and tested to analyse the spatial distribution of a mark, which could be a tree characteristic such as diameter or height, between two different types of points, which could be two different tree species. The proposed function was a conditional density function based on the intertype Krs(d) function, incorporating as test function the correlation of the marks between pairs composed of points of different types. The results obtained in simulated and real plots prove that the function is capable of revealing the scale at which spatial correlation of the mark between two types of points exists. The proposed function allows the spatial association between individuals of different species at different life stages to be identified. This analysis may reveal information on species ecology and interspecific interactions in forest ecosystems. 相似文献
104.
105.
Summary. Increased abundance of several aliphatic benzyl
and phenylethyl alkanoates were previously associated with
reduced defoliation of
Eucalyptus globulus Labill. by the
autumn gum moth (Mnesampela privata Guenée) in two
clonally replicated F2 families. We examine the robustness
of this association by comparing the abundance of the
implicated foliar wax compounds with defoliation levels in
three plantation sites and a genetics trial in northern
Tasmania. At all locations, the aliphatic alkanoate, benzyl
n-tetracosanoate (C24), was found in significantly higher
abundance in the foliar wax of E. globulus trees that had displayed low M. privata damage (designated resistant) compared to trees that had displayed high damage (designated
susceptible). Further, when sites were combined, benzyl
n-tetracosanoate (C24) accounted for 16 % of variation in
field defoliation. Field defoliation was also positively correlated
to M. privata oviposition both in the field and on
foliage sprigs in a cage. In the cage bioassay, oviposition
accounted for 20 % of variation in field defoliation
making it a better predictor of tree defoliation in the field
than either field oviposition, which accounted for 9 % of
variation, or screening foliage for the abundance of benzyl
n-tetracosanoate (C24). Despite both benzyl n-tetracosanoate
(C24) and oviposition being related to field defoliation, there
was no statistically significant relationship between the
abundance of benzyl n-tetracosanoate (C24) and oviposition
in the field or cage bioassay. Further work is therefore
required to determine if increased levels of this compound in
the foliar wax operates as a direct deterrent to M. privataoviposition. 相似文献
106.
T. J. Bergman J. C. Beehner D. L. Cheney R. M. Seyfarth P. L. Whitten 《Behavioral ecology and sociobiology》2006,59(4):480-489
To date, research on testosterone and behavior has focused on individuals, even when studying social behaviors that necessarily
involve multiple participants. Here, we explore male responses to other males of different dominance ranks and testosterone
levels in a population of wild baboons. In chacma baboons (Papio hamadryas ursinus) of the Okavango Delta, a male’s testosterone is related to his rank trajectory and, therefore, the threat he poses to other
males. To examine the effects of testosterone and rank on male–male interactions, we used playback experiments to measure
how a target male responded to the simulated approach of another male, scoring responses by whether or not the subject moved
away from the speaker in the first minute. High testosterone subjects did not move away from the speaker more often than low
testosterone subjects, but high testosterone callers elicited a move more often than low testosterone callers. When the combined
testosterone of the subject and caller was high, moves were most common. The rank relationship between subject and caller
did not predict moves, but the effect of combined testosterone on moving was most pronounced in adjacently ranked males. Adjacently
ranked, high testosterone males are the most likely to be competing for each others’ rank, and our experiments on these dyads
elicited the most moves. Both behavioral and experimental observations indicate that testosterone may be more important than
the rank relationship in predicting the outcome of male–male interactions. Furthermore, combined information on the testosterone
of both males was the best predictor of results, highlighting the utility of dyadic analyses when relating testosterone to
behavior. 相似文献
107.
Yamazaki K 《Die Naturwissenschaften》2008,95(7):671-676
Several recent hypotheses on the adaptive significance of autumn leaf colours have focused on specialist aphids. However, these hypotheses have overlooked several factors: the preferential investment by healthy vigorous trees in growth rather than defence against herbivores, variation among aphid species in their responses to bright autumn leaves and plant defences and the occurrence of tritrophic interactions in tree crowns. I incorporate these factors into a hypothesis that autumn leaf colours signal tree quality to myrmecophilous specialist aphids, with the aphids, in turn, attracting aphid-tending ants during the following spring, and the ants defending the trees from other aphids and herbivores. Therefore, bright autumn leaves may have adaptive significance, attracting myrmecophilous specialist aphids and their attending ants and, thus, reducing herbivory and competition among aphids. 相似文献
108.
Caudal autotomy is an effective antipredator strategy widespread among lizards. The shed tail thrashes vigorously for long periods to distract the predator and facilitate the lizard's escape. This movement is maintained by energy supplied by the anaerobic conversion of glycogen into lactate. It has been suggested that lactate accumulation serves as an index for the vigor of tail thrashing. We made three predictions: (1) tail loss frequency should be higher under heavier predation regime, (2) the duration of postautotomy tail movement should be extended in populations under heavy predation pressure as an adaptation to the higher risk and the increased need for defense, and (3) as result, lactate in these tail tissues should be concentrated at higher levels. To eliminate the impact of phylogeny and environmental factors on the interpretation of our result, we focused exclusively on one species, the Balearic lizard (Podarcis lilfordi). We studied three populations under different predation pressure but sharing the same climatic conditions. We found no differences among the studied populations either in postautotomy duration of tail movement or in levels of final lactate accumulation while autotomy frequency was higher where predation pressure was more intense. Tail loss effectiveness is directly influenced by the level of predation, while secondary features of the trait appear to remain independent from the impact of environment. 相似文献
109.
Philippe Quevauviller Author vitae 《Environmental Science & Policy》2011,14(7):722-729
Climate change impacts on the hydrological cycle, e.g. leading to changes of precipitation patterns, have been observed over several decades. Higher water temperatures and changes in extremes hydrometeorological events (including floods and droughts) are likely to exacerbate different types of pressures on water resources with possible negative impacts on ecosystems and human health. In addition, sea-level rise is expected to extend areas of salinisation of groundwater and estuaries, resulting in a decrease of freshwater availability for humans and ecosystems in coastal areas. Furthermore, climate-related changes in water quantity and quality are expected to affect food availability, water access and utilisation, especially in arid and semi-arid areas, as well as the operation of water infrastructure (e.g. hydropower, flood defences, and irrigation systems). This paper serves as an introduction to the special issue of Environment Science & Policy dealing with climate change impacts on water-related disasters. It provides a brief background about relevant EU water policies and examples of EU-funded research trends which illustrate on-going efforts to improve understanding and modelling of climate changes related to the hydrological cycles at scales that are relevant to decision making (possibly linked to policy). 相似文献
110.
好氧颗粒污泥能有效降解氯苯胺类化合物,然而,其同步高效降解的性能和基质间作用模式尚不清楚。文章考察好氧颗粒污泥体系降解和矿化氯苯胺类化合物的性能,并深入探讨同步降解过程中,各基质间的促进或抑制效应。实验结果表明,该体系降解单一氯苯胺类化合物遵循合Luong动力学模型,邻氯苯胺(2-CA)、间氯苯胺(3-CA)、对氯苯胺(4-CA)最大降解浓度(Sm)分别为:678.1 mg/L,837.7 mg//L和819.8 mg/L;好氧颗粒污泥体系能够完全降解和矿化总浓度低于750 mg/L的氯苯胺混合物,各化合物间降解速率符合3-CA>4-CA>2-CA。当氯苯胺类化合物共存时,相互间存在竞争性抑制作用,其中,2-CA对3-CA和4-CA的抑制作用明显小于后两者混合的相互抑制作用;对于2-CA的生物降解,3-CA的抑制作用小于4-CA。 相似文献