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171.
172.
The influence of silicon on responses to copper excess was studied in plants of Erica andevalensis. Plantlets were grown in nutrient solutions containing two Cu (1 and 500 μM) and three Si concentrations (0, 0.5 and 1 mM). Plant growth, water content, and mineral nutrient concentration were determined. Plants grown with 500 μM Cu showed differences in growth and shoot water content depending on Si supply. The addition of 1 mM Si in high-Cu nutrient solutions significantly improved plant growth and reduced water loss preventing plant death related to Cu-excess. Silicon supply reduced significantly leaf Cu concentration (up to 32%) and increased Cu concentration in roots. Phytoliths isolated from leaves were analysed by scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy. Such phytoliths consisted in silica deposits associated with Cu and other elements (K, Ca, P). Improvement by Si of Cu tolerance in E. andevalensis was clearly related to the inhibition of Cu upward transport. The leaf phytoliths formed in Si-treated plants might have some contribution to tolerance by Cu immobilisation and inactivation.  相似文献   
173.
Environmental Science and Pollution Research - As the presence of antibiotics in environmental waters enhances antimicrobial resistance, photolysis and heterogeneous photocatalysis of...  相似文献   
174.
Despite the buoyant expansion of Latin America's mining sector, the small-scale mining sub-sector remains marginalized. For many countries with small-scale mining resources, the way forward to sustainable mining development is not clear. Activities, in far too many cases, have led to environmental damage, social inequity and political violence among mining communities. This article, through a case study of the Bolivian Altiplano, seeks to advance the understanding of the conditions that drive mining communities into the chain of events of impoverishment associated with environmental damage. It also examines the opportunities for sustainable human development among these communities. In Bolivia's mining sector, social inequity is pervasive and holds the mineral resources captive. This situation is further aggravated by the fact that solutions, in the short term, are uncertain. Unresolved social inequity compromises foreign direct investments since social considerations are becoming increasingly important to mining corporations when deciding whether to invest. This article outlines a preliminary strategy to move forward on social inequity. The strategy revolves mainly around implementing alternative sustainable livelihoods with the participation of the government (central and local), the private sector, NGOs and donors as facilitators and partners. Its aim is to reduce the number of families eking out a living from artisanal mining in order to enhance the viability of small-scale mining. It is hoped that, as social inequity decreases throughout the sector, the increased stability will enable stakeholders to consider foreign direct investments within the framework of the country's sustainable human development goals.  相似文献   
175.

The study addresses in vitro degradation potential of airborne Aspergillus and Penicillium/Talarmyces species originating from cultural heritage conservation premises. A series of rapid, cost effective biodegradation assays were performed to assess production of extracellular pigments, acids, and enzymes. Most of the isolates have demonstrated positive growth in at least one of the preformed tests. Strongest overall degradation potential was demonstrated for Penicillium brevicompactum, P. glabrum, and Talaromyces sayulitensis while Aspergillus domesticus, A. penicillioides, A. pseudoglaucus, and A. ruber did not exhibit positive reaction in any of the employed assays. Majority of isolates exhibited proteolytic and cellulolytic activity while carbonate dissolution was observed for only five tested fungi. Highest alteration of pH value in liquid media was documented for T. sayulitensis while A. niger and P. expansum exhibited strongest acid production on CREA. Certain isolates, mostly Penicillium species, displayed production of extracellular pigments. The results imply that many of the tested fungi have significant biodegradation capacity, indicating their potential to inflict structural and esthetic alterations on cultural heritage objects.

  相似文献   
176.
This study aims to characterize the different types of certification in the Brazilian citriculture as well as analyze the major changes in the market. The paper also has the objective to discuss how social and environmental factors influence the demand for food certifications and the sustainability and ethics aspects in the field. Therefore, a literature review on the subject was carried out as well as a qualitative research using interviews with certifiers, governmental institutions, farmers, cooperatives and producer associations. The certification is becoming mandatory for those working in foreign markets and for those working nationally; it can be a competitive differential. The organic certification in citriculture shows the highest number of growers. Companies with large areas of citrus and the orange juice processing industry are adhering to this certification in order to maintain themselves competitive in the market. There is an enormous potential of Brazilian citriculture certification, because the certified area is still less than 6 % of the total area. Certification reduces the asymmetry of information and consists of an important step towards sustainability although incapable of solely guaranteeing it.  相似文献   
177.
Semi-arid Mediterranean regions are highly susceptible to desertification processes which can reduce the benefits that people obtain from healthy ecosystems and thus threaten human wellbeing. The European Union Biodiversity Strategy to 2020 recognizes the need to incorporate ecosystem services into land-use management, conservation, and restoration actions. The inclusion of ecosystem services into restoration actions and plans is an emerging area of research, and there are few documented approaches and guidelines on how to undertake such an exercise. This paper responds to this need, and we demonstrate an approach for identifying both key ecosystem services provisioning areas and the spatial relationship between ecological processes and services. A degraded semi-arid Mediterranean river basin in north east Spain was used as a case study area. We show that the quantification and mapping of services are the first step required for both optimizing and targeting of specific local areas for restoration. Additionally, we provide guidelines for restoration planning at a watershed scale; establishing priorities for improving the delivery of ecosystem services at this scale; and prioritizing the sub-watersheds for restoration based on their potential for delivering a combination of key ecosystem services for the entire basin.  相似文献   
178.
Abstract

Glucomannan is a highly branched polysaccharide with glycosidic linkages, constituted of mannoses and glucoses. In recent years, its usefulness due to its immunological, antioxidant and antimutagenic activity has been recognized. The aim of the study was to determine the antigenotoxic ability of glucomannan extracted from Candida utilis orally administered (100–700?mg/kg) to mice, which subsequently received 1?mg/kg aflatoxin B1. Hepatocytes obtained from these animals 4–16?h post administration were examined by means of the comet assay. The antigenotoxic effect was found to be higher than that observed in previous studies with α-mannan and β-D-glucan isolated from Saccharomyces cerevisiae., In order to explore the possibility of formation of a supramolecular complex between glucomannan and aflatoxin B1, both compounds were co-crystallized, their melting points determined, and the complex analyzed through ultraviolet spectroscopy. The spectroscopy data suggest that the protective effect of glucomannan is related to the formation of a supramolecular complex between the two compounds.  相似文献   
179.
Indigenous Peoples’ lands cover over one-quarter of Earth's surface, a significant proportion of which is still free from industrial-level human impacts. As a result, Indigenous Peoples and their lands are crucial for the long-term persistence of Earth's biodiversity and ecosystem services. Yet, information on species composition on these lands globally remains largely unknown. We conducted the first comprehensive analysis of terrestrial mammal composition across mapped Indigenous lands based on data on area of habitat (AOH) for 4460 mammal species assessed by the International Union for Conservation of Nature. We overlaid each species’ AOH on a current map of Indigenous lands and found that 2695 species (60% of assessed mammals) had ≥10% of their ranges on Indigenous Peoples’ lands and 1009 species (23%) had >50% of their ranges on these lands. For threatened species, 473 (47%) occurred on Indigenous lands with 26% having >50% of their habitat on these lands. We also found that 935 mammal species (131 categorized as threatened) had ≥ 10% of their range on Indigenous Peoples’ lands that had low human pressure. Our results show how important Indigenous Peoples’ lands are to the successful implementation of conservation and sustainable development agendas worldwide.  相似文献   
180.
Overexploitation of wildlife populations occurs across the humid tropics and is a significant threat to the long-term survival of large-bodied primates. To investigate the impacts of hunting on primates and ways to mitigate them, we developed a spatially explicit, individual-based model for a landscape that included hunted and un-hunted areas. We used the large-bodied neotropical red howler monkey (Alouatta seniculus) as our case study species because its life history characteristics make it vulnerable to hunting. We modeled the influence of different rates of harvest and proportions of landscape dedicated to un-hunted reserves on population persistence, population size, social dynamics, and hunting yields of red howler monkeys. In most scenarios, the un-hunted populations maintained a constant density regardless of hunting pressure elsewhere, and allowed the overall population to persist. Therefore, the overall population was quite resilient to extinction; only in scenarios without any un-hunted areas did the population go extinct. However, the total and hunted populations did experience large declines over 100 years under moderate and high hunting pressure. In addition, when reserve area decreased, population losses and losses per unit area increased disproportionately. Furthermore, hunting disrupted the social structure of troops. The number of male turnovers and infanticides increased in hunted populations, while birth rates decreased and exacerbated population losses due to hunting. Finally, our results indicated that when more than 55% of the landscape was harvested at high (30%) rates, hunting yields, as measured by kilograms of biomass, were less than those obtained from moderate harvest rates. Additionally, hunting yields, expressed as the number of individuals hunted/year/km2, increased in proximity to un-hunted areas, and suggested that dispersal from un-hunted areas may have contributed to hunting sustainability. These results indicate that un-hunted areas serve to enhance hunting yields, population size, and population persistence in hunted landscapes. Therefore, spatial regulation of hunting via a reserve system may be an effective management strategy for sustainable hunting, and we recommend it because it may also be more feasible to implement than harvest quotas or restrictions on season length.  相似文献   
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