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151.
The emergence of problems such as nitrate pollution has drawn attention to the need for integrated management of land and water resources. Integrated management approaches require appropriate institutional arrangements. Unfortunately, in many countries, land and water resources are managed on a sectoral basis and institutions were not designed to deal with complex environmental problems. Institutional arrangements for management of nitrate pollution are evaluated on the basis of seven criteria. Results indicate that some progress was made after 1985 regarding inter-agency co-ordination, public participation, the mix of strategies and adaptive capacity. Nevertheless, key substantive issues involving equity, efficiency and effectiveness were not adequately resolved. Policy referral, catchment management planning, bargaining and negotiation are recommended as key processes and mechanisms for improved management of the nitrate problem.  相似文献   
152.
This paper is concerned with the effects of advanced manufacturing technology on shopfloor operator jobs and work attitudes. A strong line of argument from labour process theory suggests that such technology will simplify and deskill jobs, and reduce the quality or working life. This proposition was explored within a large electronics company which assembles computer boards, where two different applications of information technology have been experienced. These were compared with two traditional manual assembly jobs. Assessment of job content, perceived job characteristics and operator work attitudes, showed no uniform deskilling effects of advanced manufacturing technologies. Much larger differences existed both between the different new technology applications and between the traditional jobs. This demonstrates that choice of technology is important to skill use and employees' attitudes, as are the choices for the organization of work around it. These are not uniform processes even within a single organization. Experience of operating advanced manufacturing technology was also accompanied by more positive views concerning its impact on the shopfloor.  相似文献   
153.
Zonation patterns of gorgonians from 15 sites on reefs south of the main island of Singapore reveal discontinuities in terms of both generic richness and total abundance. This establishes the crest, slope, and bottom as ecologically distinct environments of the reef, as interpreted by these gorgonian population parameters. Only members of the family Melithaeidae are able to colonise all three zones. Other genera are restricted to the slope and bottom; in particular, Acanthogorgia and Echinomuricea are only found at the bottom zone.  相似文献   
154.
To control the outbreak of foot and mouth disease, which occurred in the UK in early 2001, a large number of farm animals were slaughtered. Where it was not possible to render or landfill the carcasses, they were destroyed by burning on open pyres, with wood, coal and other materials. Uncontrolled combustion such as this is known to produce small quantities of dioxins and an investigation was made into whether, as a result of the burning, there was an elevation in the concentrations of these compounds in food produced in the areas close to the pyres. With few exceptions, concentrations of PCDD/Fs and PCBs were within the expected ranges as predicted by reference data. No accumulation over time was evident from a repeat milk sampling exercise. Where elevated concentrations of PCDD/Fs and PCBs were found in chickens and eggs, they were in samples not destined for the food chain. Elevated levels in some samples of milk from Dumfries and Galloway were not found in earlier or later samples and may have been found as a result of a temporary feeding regime. Elevated concentrations in lamb from Carmarthenshire were from very young animals which would not have entered the food chain. There was no evidence of any significant increase in dietary exposure to PCDD/Fs and PCBs as a result of the FMD pyres.  相似文献   
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157.
Conflicts between protected-area managers and local people are common, but the drivers of conflict are rarely analyzed. This limits opportunities to identify strategies that reduce conflict and the magnitude of resulting threats to conservation. Integrated conservation and development (ICD) was adopted at Bwindi Impenetrable Forest, Uganda, to reduce conflict during gazettement of the national park, but the success of this approach remains contested. We retrieved documents of conflict written by park staff and local people from 1986 through 2000 (before, during, and after gazettement). We extracted data on 48 incidences of violent conflict and categorized them by gazettement period, area, instigator, and type to undertake a historical analysis of the triggers of violent conflict at Bwindi. Before and during gazettement, local villagers instigated most of the conflict incidents when law-enforcement efforts sought to halt commercial activities within Bwindi. No conflict arose from the arrest of villagers collecting subsistence resources during these periods. After gazettement, prohibitions on commercial activities continued to drive conflict even though villagers collecting subsistence resources were arrested more frequently than before gazettement, and local attitudes toward the park had improved following receipt of ICD benefits. Law-enforcement efforts targeted commercial activities to reduce this threat to Bwindi's mountain gorillas (Gorilla beringei beringei), although the activities remained important income sources for people in villages near Bwindi. Losing commercial income following gazettement therefore appeared to be their primary motivation for instigating conflict with park rangers. Prohibitions on subsistence resource use triggered conflict less often. Our use of typologies for a multivariate conflict analysis demonstrates that by identifying differences between effects of conservation as drivers of conflict, conflict analysis can enable a more strategic deployment of conflict-resolution measures that could further conservation efforts. At Bwindi targeting ICD toward individuals who lost benefits from commercial activities may strengthen the role of ICD in conflict resolution and conservation.  相似文献   
158.
The major inorganic and organic osmolytes responsible for hydrating the oocytes during pre-ovulatory meiotic maturation in autumn- and spring-spawning stocks of Atlantic herring are examined. Despite the ovulated eggs of spring-spawning herring being 1.6- to 2-fold larger than the autumn-spawning stock, the GSI (27 ± 3%) and degree of oocyte hydration (70–72% water) were similar. Normalising the data with respect to dry mass revealed that the physiological mechanisms underlying the maturational influx of water were the same for both classes of egg. Cl, K+ and Pi together with a small pool of free amino acids (FAA) represented the driving forces for oocyte hydration. K+ (autumn and spring) and Pi (spring) maintained their concentrations in the ovulated eggs, while all other ions, including Cl, Na+, NH4 + and Mg2+ were significantly diluted. In contrast the FAA concentration increased during the hydration process. Amongst the inorganic ions, Cl showed the greatest increase in the ovulated eggs. The FAA content doubled from 1.5 to 3.3% of dry mass during oocyte hydration and accounted for 29% of the calculated ovoplasmic osmolality in the ovulated eggs from both autumn- and spring-spawners. This significant osmotic effect of the small pool of FAA was due to the low water content of the benthic eggs. The differential movement of the inorganic and organic osmolytes that underly oocyte hydration in Atlantic herring are discussed in relation to current models of transmembrane ion flux.  相似文献   
159.
When reproduction competes with the amount of resources available for survival during an unpredictable nonbreeding season, individuals should adopt a risk-sensitive regulation of their reproductive allocation. We tested this hypothesis on female reindeer (Rangifer tarandus), which face a trade-off between reproduction and acquisition of body reserves during spring and summer, with autumn body mass functioning as insurance against stochastic winter climatic severity. The study was conducted in a population consisting of two herds: one that received supplementary winter feeding for four years while the other utilized natural pastures. The females receiving additional forage allocated more to their calves. Experimental translocation of females between the herds was conducted to simulate two contrasting rapid alterations of winter conditions. When females receiving supplementary feeding were moved to natural pastures, they promptly reduced their reproductive allocation the following summer. However, when winter conditions were improved, females were reluctant to increase their reproductive allocation. This asymmetric response to improved vs. reduced winter conditions is consistent with a risk-averse adjustment in reproductive allocation. The ability of individuals to track their environment and the concordant risk-sensitive adjustment of reproductive allocation may render subarctic reindeer more resilient to climate change than previously supposed.  相似文献   
160.
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