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31.
Aim. The purpose of this study was to examine the associations between various health and fitness measures and Functional Movement Screen? (FMS?) scores among 78 firefighter recruits. Methods. Relationships between FMS? scores and age, body mass index (BMI), sit and reach (S&R) distance, estimated maximal aerobic capacity (O2max), estimated one-repetition maximum squat (1RM-Squatmax), and plank endurance (%Plankmax) were examined. Results. Total FMS? scores were significantly correlated with BMI (r?=??0.231, p?=?0.042), estimated 1RM-Squatmax (r?=?0.302, p?=?0.007), and %Plankmax (r?=?0.320, p?=?0.004). Multiple regression analyses indicated that this combination of predictors significantly predicted (F(3, 74)?=?5.043, p?=?0.003) Total FMS? score outcomes and accounted for 17% of the total variance (R2?=?0.170). In addition, logistic regression analyses indicated that estimated 1RM-Squatmax also significantly predicted (χ2?=?6.662, df?=?1, p?=?0.010) FMS? group membership (≤14 or ≥15). Conclusion. These results suggest that the health and fitness measures of obesity (BMI), bilateral lower extremity strength (estimated 1RM-Squatmax), and core muscular endurance (%Plankmax) are significantly associated with functional movement patterns among firefighter recruits. Consequently, injury prevention programs implemented among firefighter recruits should target these aspects of health and fitness.  相似文献   
32.
We evaluated the abundance of nonnative plants on fuel breaks and in adjacent untreated areas to determine if fuel treatments promote the invasion of nonnative plant species. Understanding the relationship between fuel treatments and nonnative plants is becoming increasingly important as federal and state agencies are currently implementing large fuel treatment programs throughout the United States to reduce the threat of wildland fire. Our study included 24 fuel breaks located across the State of California. We found that nonnative plant abundance was over 200% higher on fuel breaks than in adjacent wildland areas. Relative nonnative cover was greater on fuel breaks constructed by bulldozers (28%) than on fuel breaks constructed by other methods (7%). Canopy cover, litter cover, and duff depth also were significantly lower on fuel breaks constructed by bulldozers, and these fuel breaks had significantly more exposed bare ground than other types of fuel breaks. There was a significant decline in relative nonnative cover with increasing distance from the fuel break, particularly in areas that had experienced more numerous fires during the past 50 years, and in areas that had been grazed. These data suggest that fuel breaks could provide establishment sites for nonnative plants, and that nonnatives may invade surrounding areas, especially after disturbances such as fire or grazing. Fuel break construction and maintenance methods that leave some overstory canopy and minimize exposure of bare ground may be less likely to promote nonnative plants.  相似文献   
33.
ABSTRACT: Sediment bound trace metals are often examined for spatial trends such as downstream patterns or distance from a source. Spatial trends may indicate either differences in metal inputs, or, when considerable sediment variability exists, differences in sediment sorption processes. These two possibilities become important not only when sediment contamination is evaluated within an area, but also when regulatory agencies attempt to make equivalent among area decisions. Sediments from an urban watershed were examined for: (1) downstream trace metal trends and (2) sediment sorption relationships. Analyses determined that downstream trenda as related to metal inputs could not be recognized by analyzing the < 2mm (≤, sand) sediment size fraction. Conversely, the trace metal concentrations were found to be distinctly related to sediment characteristics. The watershed's metal concentrations are similar to those found in uncontaminated to slightly contaminated sediments in the United States.  相似文献   
34.
What is the significance of the wicked problems framework for environmental philosophy? In response to wicked problems, environmental scientists are starting to welcome the participation of social scientists, humanists, and the creative arts. We argue that the need for interdisciplinary approaches to wicked problems opens up a number of tasks that environmental philosophers have every right to undertake. The first task is for philosophers to explore new and promising ways of initiating philosophical research through conducting collaborative learning processes on environmental issues. The second task is for philosophers to recognize the value of philosophical skills in their engagements with members of other disciplines and walks of life in addressing wicked problems. The wicked problems framework should be seen as an important guide for facilitating philosophical research that is of relevance to problems like climate change and sustainable agriculture.  相似文献   
35.
A study of the piedmont of the Newberry Mountains near Laughlin, Nevada, demonstrates that geologic information can improve the scientific basis of flood‐hazard management on alluvial fans in desert areas. Comparison of geologic information against flood insurance rate maps (FIRMs) reveals flaws in conventional methods for flood hazard delineation in this setting. Geologic evidence indicates that large parts of the Newberry piedmont have been isolated from significant flooding for at least the past 10,000 years. This contrasts with existing FIRMs that include large tracts of nonflood prone land in the 100‐year and 500‐year flood hazard zones and exclude areas of indisputably flood prone land from the regulatory flood plain. From the basis of the geology, flood hazards on at least one‐third of the piedmont are mischaracterized on the regulatory maps. The formal incorporation of geologic data into flood hazard studies on desert piedmonts could significantly reduce this type of discrepancy and substantially reduce the scope, hence cost, of more elaborate engineering studies and hazard mitigation strategies. The results of this study affirm the value of new Federal Emergency Management Agency (FEMA) recommendations for characterizing alluvial fan flood hazards and support an argument for mandating geological studies in the regulatory process.  相似文献   
36.
Consumer products can emit chlorinated volatile organic compounds (CVOCs) that complicate vapor intrusion (VI) assessments. Assessment protocols acknowledge the need to remove these products during VI investigations, but they can be problematic to identify and locate. Predicting if the products cause detectable air concentrations is also difficult since emission rate information is limited and can vary with product use and age. In this study, the emission rates of 1,2-dichloroethane, trichloroethene, tetrachloroethene, and carbon tetrachloride from four consumer products identified as indoor sources during VI field investigations were measured under laboratory conditions using a flow through system. Emissions of PCE from an adhesive container tube ranged from 1.33 ± 1.13 μg/min (unopened) to 23.9 ± 2.93 μg/min (previously opened). The laboratory-measured emission rates were used to estimate indoor air concentrations, which were then compared to concentrations measured after the products placed were into an actual residence. The estimated and measured indoor air concentrations were generally comparable, showing that emission rate information can be used to determine the relative impact of internal CVOC sources.  相似文献   
37.
38.
Hatcheries have long been used in an attempt to mitigate for declines in wild stocks of Pacific salmon (Oncorhynchus spp.), though the conservation benefit of hatcheries is a topic of ongoing debate. Irrespective of conservation benefits, a fundamental question is whether hatcheries will be able to function as they have in the past given anticipated future climate conditions. To begin to answer this question, we developed a deterministic modeling framework to evaluate how climate change may affect hatcheries that rear Pacific salmon. The framework considers the physiological tolerances for each species, incorporates a temperature-driven growth model, and uses two metrics commonly monitored by hatchery managers to determine the impacts of changes in water temperature and availability on hatchery rearing conditions. As a case study, we applied the model to the US Fish and Wildlife Service’s Winthrop National Fish Hatchery. We projected that hatchery environmental conditions remained within the general physiological tolerances for Chinook salmon in the 2040s (assuming A1B greenhouse gas emissions scenario), but that warmer water temperatures in summer accelerated juvenile salmon growth. Increased growth during summer coincided with periods when water availability should also be lower, thus increasing the likelihood of physiological stress in juvenile salmon. The identification of these climate sensitivities led to a consideration of potential mitigation strategies such as chilling water, altering rations, or modifying rearing cycles. The framework can be refined with new information, but in its present form, it provides a consistent, repeatable method to assess the vulnerability of hatcheries to predicted climate change.  相似文献   
39.
Edwards KF  Klausmeier CA  Litchman E 《Ecology》2011,92(11):2085-2095
Trade-offs among functional traits are essential for explaining community structure and species coexistence. While two-way trade-offs have been investigated in many systems, higher-dimensional trade-offs remain largely hypothetical. Here we demonstrate a three-way trade-off between cell size and competitive abilities for nitrogen and phosphorus in marine and freshwater phytoplankton. At a given cell size, competitive abilities for N and P are negatively correlated, but as cell size increases, competitive ability decreases for both nutrients. The relative importance of the two trade-off axes appears to be environment dependent, suggesting different selective pressures: freshwater phytoplankton separate more along the N vs. P competition axis, and marine phytoplankton separate more along the nutrient competition vs. cell size axis. Our results demonstrate the multidimensional nature of key trade-offs among traits and suggest that such trade-offs may drive species interactions and structure ecological communities.  相似文献   
40.
Participatory approaches to environmental decision making and assessment continue to grow in academic and policy circles. Improving how we understand the structure of deliberative activities is especially important for addressing problems in natural resources, climate change, and food systems that have wicked dimensions, such as deep value disagreements, high degrees of uncertainty, catastrophic risks, and high costs associated with errors. Yet getting the structure right is not the only important task at hand. Indeed, participatory activities can break down and fail to achieve their specific goals when some of the deliberators lack what we will call participatory virtues. We will argue for the importance of future research on how environmental education can incorporate participatory virtues to equip future citizens with the virtues they will need to deliberate about wicked, environmental problems. What is the role of education for deliberative skills and virtues relative to other aspects of environmental education, such as facts and values education? How important is it relative to careful design of the deliberative process? What virtues really matter?  相似文献   
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