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ABSTRACTAnalyses of climate engineering (CE) governance have accelerated in the last decade. A key claim is that CE remains a largely ungoverned space, with shared norms, institutional arrangements, and formal rules to regulate CE not yet present. In contrast, here it is argued that de facto governance of CE is underway, discernible in an ordering of this nascent field of inquiry by unacknowledged sources of steering. One key source of de facto governance is analyzed: high-level ‘authoritative assessments’ of CE. The focus is on how these assessments are constructing CE as an object of governance through demarcating and categorizing this emerging field of inquiry, and how this contributes to normalizing and institutionalizing CE research (and CE research communities). Scrutinizing the distinct nature and political implications of de facto governance, particularly of novel and speculative technological trajectories not yet subject to formal steering, remains a key task for governance scholars. 相似文献
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Ina Maren Sieber Robbert Biesbroek Debora de Block 《Regional Environmental Change》2018,18(8):2379-2390
Many climate change adaptation scholars recognise the complexities in the governance of adaptation. Most have used the concept of ‘barriers to adaptation’ in an attempt to describe why governance of adaptation is challenging. However, these studies have recently been critiqued for over simplifying complex governance processes by referring to the static concept of barriers, thereby ignoring dynamic complexity as a root explanatory cause. This paper builds the argument that how barriers are currently used in the literature is insufficient to explain why the governance of adaptation often proves difficult. We adopt a so-called mechanism-based approach to investigate how and why the governance of ecosystem-based adaptation (EbA) reaches impasses in five cases in Thailand and the Netherlands. Our findings show six causal mechanisms that explain impasses in the five case studies: (1) frame polarisation, (2) timing synchronisation, (3) risk innovation, (4) rules of the game, (5) veto players and (6) lost in translation. Several of these causal mechanisms are recurring and emerge under specific contextual conditions or are activated by other mechanisms. Our findings provide valuable insights into the impasses in the governance of EbA and allow for critical reflections on the analytical value of the mechanism-based approach in explaining why the governance of adaptation proves difficult and how this can be overcome. 相似文献
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The mechanisms of regulating worker reproduction in bumblebees were studied by direct behavioral observations and by measuring
ovarian development and juvenile hormone (JH) biosynthesis rates in workers under different social conditions. Workers in
the last stage of Bombus terrestris colony development (the competition phase) had the lowest ovarian development and JH biosynthesis rates. Callows introduced
into colonies immediately after queen removal (dequeened colonies) demonstrated a significant increase in ovarian development
before, but not during, the competition phase. These findings differ from the higher ovarian development in colonies during
the competition phase predicted by the prevailing hypothesis that worker reproduction starts in response to a decrease in
queen inhibition. Reproduction of callows housed with dominant workers in small queenless groups was inhibited as in queenright
colonies. This suggests that the reduced ovarian development and JH biosynthesis rates observed in dequeened and normally
developing colonies during the competition phase also reflect inhibition by dominant workers. Thus, two distinct stages of
inhibition of reproduction seem to exist: (1) before the competition phase, when the queen slows down worker ovarian development
and prevents oviposition; (2) during the competition phase, when dominant workers inhibit ovarian development of other workers.
Between these stages there seems to be a temporal “window” of enhanced worker reproductive development. The queen's typical
switch to haploid egg production was not associated with changes in worker ovarian development or JH biosynthesis rates. These
findings suggest that regulation of worker reproduction in B. terrestris is not determined by simple changes in the queen's inhibition capacity or by the sex of offspring and that the worker's role
is more important than previously believed.
Received: 18 March 1998 / Accepted after revision: 18 July 1998 相似文献
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Dalvie MA Naik I Channa K London L 《Journal of environmental science and health. Part. B》2011,46(2):163-172
The study investigated urinary levels of dialkyl phosphates resulting from pesticide exposure amongst 40 farm workers. Workers were tested (urinary dialkyl phosphate levels, anthropometry, short exposure questionnaire) before and after the first day of seasonal chlorpyrifos spraying. Median baseline urinary dialkyl phosphates was high amongst both non-applicators (1587.5 μg/g creatinine, n = 8) and applicators (365.6 μg/g creatinine, n = 9). There was not much evidence of an increase in post-spray dialkyl phosphates levels from pre-spray levels amongst both applicators and non-applicators. Hours mixing, spraying, driving a tractor and hours worked by non-applicators were not significantly associated with an increase in post-spray dialkyl phosphate levels, adjusting for age, height, weight, gender, use of empty pesticide containers and self-reported kidney problems. Past applicator status was weakly positively associated with pre-spray dialkyl phosphate levels adjusting for age, height, weight, and gender, self-reported kidney problems, smoking and alcohol (β= 1019.5, p = 0.307, R2 = 0.28). The high dialkyl phosphate levels call for an epidemiological investigation into the health effects of organophosphorous pesticides. 相似文献
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Christopher Reyer Johann Bachinger Ralf Bloch Fred F. Hattermann Pierre L. Ibisch Stefan Kreft Petra Lasch Wolfgang Lucht Christoph Nowicki Peter Spathelf Manfred Stock Martin Welp 《Regional Environmental Change》2012,12(3):523-542
Located in a relatively dry region and characterized by mainly sandy soils, the German Federal State of Brandenburg (surrounding the capital city of Berlin) is especially vulnerable to climate change impacts (e.g., summer droughts) and cascading effects on ecological systems (e.g., decreasing ground water tables, water stress, fire risk, productivity losses) with socioeconomic implications. Furthermore, a complex interplay of unemployment, rural exodus, and an aging population challenges this structurally weak region. We discuss adaptation measures that are either implemented or planned, as well as research into adaptation strategies to climate change for the sectors forestry, agriculture, and water management as well as in nature conservation in light of socioeconomic and ecological challenges and benefits. In doing so, we adopt a systemic view of Brandenburg where the sectors discussed are seen as subsystems embedded in a larger regional system. This at least partially holarchical approach enables the identification of conflicts between adaptation measures, but also of synergies among the sectors that pertain to successful adaptation to climate change. The insights gained ultimately highlight the need for cross-sectoral, adaptive management practices that jointly target a sustainable regional development. 相似文献
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Total DDT and PCB concentrations were determined in blubber of 130 long-finned pilot whales, Globicephala melas (100 females and 30 males) from the Faroe Islands (northern north-east Atlantic). In males and immature females no relation was observed between age and organochlorine concentrations or the ratio of tDDT (total DDT)/PCB; in contrast, concentrations and ratios in mature females declined with age, which is attributed to reproductive transfer to their offspring during gestation and lactation. Relative abundance of DDE respective to tDDT increased in males and young females and decreased in mature females. Organochlorine transfer to offspring during lactation was found to represent about 60-100% of the mother's body load, while that occurring during gestation was estimated to be much lower, in the range 4-10% of mother's body load. Transfer rates tended to decrease with mother's age and were, consequently, much higher in primiparous females than in those that had already given birth. Transplacental rates were found to be consistent with the ratio between mother's body weight and neonatal body weight. 相似文献
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Kizinievič Olga Voišnienė Violeta Kizinievič Viktor Pundienė Ina 《Journal of Material Cycles and Waste Management》2022,24(1):237-249
Journal of Material Cycles and Waste Management - This paper presents an experimental study on the properties, structure and durability (frost resistance: one-side and all-sides freezing and... 相似文献
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