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161.
Given the importance of markets and fairs for the commerce of medicinal plants, an ethnobotanical study was undertaken at the Caruaru Fair (Pernambuco, northeastern Brazil) to compare the richness of species sold and their values of relative importance (RI) using two datasets collected with a 4-year interval. The seasonality of these plants?? supplies was also analyzed. The Caruaru Fair is located in the 18 de Maio Park. It covers an area 40,000?m2 and is used by merchants who sell several types of products, such as supplies, handicrafts, clay and aluminum utensils, shoes, clothes and medicinal plants. Semistructured interviews were carried out with the vendors who agreed to take part in the study in order to record which plants were sold and their respective indications. The plants were collected, and the species were determined. The information was analyzed with quantitative tools. A total of 169 plants were identified from both surveys, which were significantly different with regard to species richness (p?<?0.05) but did not vary in relation to species?? Relative Importance (p?>?0.05). In relation to the seasonality of the plant supply, habit may explain the lack of some species during certain periods of the year, as most of the absent plants are herbaceous. In terms of the species most sold locally, it was found that spontaneous tree species are well known and extensively commercialized.  相似文献   
162.
Although the concept of tropical birds as sedentary is pervasive, evidence suggests many are not. Our grasp of movement status in tropical birds is decidedly poor, but the successful long-term conservation of these birds depends on such information. Sedentariness will likely doom much tropical avian diversity, but increased vagility is a two-edged sword: beneficial in promoting immigration, but detrimental in that more than one habitat may be required. Birds requiring more than one habitat may be unable to locate a particular type as landscape modifications increase. Our long-term data set from the Sierra de Los Tuxtlas in southern Veracruz, México, reveals infrequent, large-scale movements in a local highland endemic. Wetmore's Bush-Tanager ( Chlorospingus ophthalmicus wetmorei) seems occasionally dependent upon lowland forests (now greatly diminished) as a refugium from temporarily unsuitable highlands. Our data and observations lead us to three conclusions: 1) assumptions of sedentariness in tropical birds should be made with extreme caution; 2) normal, but periodic phenomena may be easily overlooked, even in relatively long-term studies; and 3) missing such phenomena jeopardizes the success of any conservation plan because over the long term a population may be dependent upon refugia only occasionally occupied.  相似文献   
163.
Environmental Science and Pollution Research - Studies have shown that domestic waste collectors are exposed to toxicants including infectious pathogens, which may be linked to their oral health...  相似文献   
164.
Environmental Science and Pollution Research - In recent decades, harmful cyanobacterial blooms (HCBs) have become a severe hazard for human health mainly in drinking water resources and are...  相似文献   
165.
The environmental performance evaluation (EPE) of organizations is becoming an autonomous management tool. The main goal of this research was to assess the state of EPE practice in the Portuguese defence sector, as a particular part of public services. A questionnaire survey was conducted involving all Portuguese military units that have a person in charge of environmental issues. The questionnaire was designed to assess: (i) the importance and drivers of EPE; (ii) the ISO 14031 knowledge and implementation; (iii) the knowledge and use of environmental indicators; (iv) the optimal format for indicators; and (v) the advantages and drawbacks of using environmental indicators. Despite various initiatives driving environmental practices in public organizations, most of that experience is only centred on an environmental management system, and EPE is quite a new issue. Nevertheless, general environmental performance evaluation is a growing reality and one in which Portuguese military units are taking an increasing interest. Overall respondents agree on the importance of measuring and communicating environmental performance related to their main missions and activities. The main drivers for EPE in military units are the prevention of health risks and compliance with regulations. However, to date, ISO 14031 and environmental performance indicators are almost unknown in the respondent military units. Among the three military branches, the Navy revealed the worst environmental performance evaluation knowledge, awareness and practice.  相似文献   
166.
Diflubenzuron (DFB) is an insecticide commonly used to control forest pests. The objectives of this study were to assess the effect of diflubenzuron on the development of Pinus pinaster seedlings and Pisolithus tinctorius under laboratory conditions and to study the possible protective role of this ectomycorrhizal fungus against the effects of diflubenzuron. In vitro experiments revealed that diflubenzuron inhibited fungal growth at all tested concentrations (0.01, 0.1, 1, 10 and 100 mg L?1). Root growth was inhibited at the two highest diflubenzuron concentrations. The activity of the antioxidant defence system of non-inoculated P. pinaster increased at 1 and 10 mg DFB kg?1 substrate, and inoculation increased the threshold to the highest concentration. The protective role of the ectomycorrhizal fungus was seen in the increase of CAT activity. This study revealed that despite causing no mortality, diflubenzuron has the ability to cause sub-lethal damage to P. pinaster. The disproportionate use of this insecticide may lead to higher amounts of its residues in soil and the biosphere, endangering trees, fungi and their symbiosis.  相似文献   
167.
The bioaccumulation of atrazine and its toxicity were evaluated for the cyanobacterium Microcystis novacekii. Cyanobacterial cultures were grown in WC culture medium with atrazine at 50, 250 and 500 μg L?1. After 96 hours of exposure, 27.2% of the atrazine had been removed from the culture supernatant. Spontaneous degradation was found to be insignificant (< 9% at 500 μg L?1), indicating a high efficiency for the bioaccumulation of atrazine by M. novacekii. There were no atrazine metabolites detected in the culture medium at any of the doses studied. The acute toxicity (EC50) of atrazine to the cyanobacterium was 4.2 mg L?1 at 96 hours demonstrating the potential for M. novacekii to tolerate high concentrations of this herbicide in fresh water environments. The ability of M. novacekii to remove atrazine combined with its tolerance of the pesticide toxicity showed in this study makes it a potential biological resource for the restoration of contaminated surface waters. These findings support continued studies of the role of M. novacekii in the bioremediation of fresh water environments polluted by atrazine.  相似文献   
168.
The development of environmental performance policy indicators for public services, and in particular for the defence sector, is an emerging issue. Despite a number of recent initiatives there has been little work done in this area, since the other sectors usually focused on are agriculture, transport, industry, tourism and energy. This type of tool can be an important component for environmental performance evaluation at policy level, when integrated in the general performance assessment system of public missions and activities. The main objective of this research was to develop environmental performance policy indicators for the public sector, specifically applied to the defence sector. Previous research included an assessment of the environmental profile, through the evaluation of how environmental management practices have been adopted in this sector and an assessment of environmental aspects and impacts. This paper builds upon that previous research, developing an indicator framework--SEPI--supported by the selection and construction of environmental performance indicators. Another aim is to discuss how the current environmental indicator framework can be integrated into overall performance management. The Portuguese defence sector is presented and the usefulness of this methodology demonstrated. Feasibility and relevancy criteria are applied to evaluate the set of indicators proposed, allowing indicators to be scored and indicators for the policy level to be obtained.  相似文献   
169.
Journal of Polymers and the Environment - This work assesses the influence of the plasticizer polyethylene glycol (PEG) on the compatibilization of poly (butylene adipate-co-terephthalate) (PBAT)...  相似文献   
170.
Corrales N  Campos M 《Chemosphere》2004,57(11):1613-1619
The influence that different styles of olive-orchard management (conventional, integrated, and organic) exert on the predator Chrysoperla carnea has been studied to strengthen this insect’s role in the integrated management against pests. For this, the adult chrysopid populations were determined by McPhail traps, and laboratory examinations were made of certain biological characteristics of the first generation of adults captured in each of the olive orchards studied. The chrysopid populations increasing significantly during some months in the integrated and organic olive orchard. The most abundant species in all the zones was C. carnea, representing 95% of all captures in the conventional olive orchard. It was found that the larvae from the integrated olive orchard took longer to develop, while the pupae from the organic orchard evolved most rapidly to adulthood. The highest mortality rate was for larvae in the conventional olive orchard. The fecundity of the females from the organic orchards was significantly greater, presumably due to their greater longevity and shorter pre-oviposition period. These results can be used to improve conservation strategies and to increase C. carnea populations and their predatory activity.  相似文献   
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