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971.
972.
Phil Cottle 《Mitigation and Adaptation Strategies for Global Change》2007,12(1):181-201
The author uses his own data gleaned from over 10 years of commercial forestry insurance across the world to propose that
despite a low intrinsic fire risk across most of Southeast Asia, especially Indonesia, commercial fire losses are unacceptably
high, and could be reduced substantially within the current financial legal and political framework within which forestry
companies operate.
Opening with a statement about the dearth of forest fire loss data in the commercial sector, it is observed that the consequent
inability of general insurers to estimate the rate of fire loss leads to very low insurance participation in forestry within
Indonesia. A summary is then provided of the financial and environmental benefits of insurance participation in commercial
forestry were this situation to be changed.
A short discussion on risk perceptions is introduced to make the point that without reliable commercial forest fire loss data,
risk perceptions of fire exposure in Southeast Asia by the financial sector, including insurers, is a barrier to risk transfer
and investment. While real fire risk and perceived fire risk for Indonesia seem at present to be in agreement, the paper challenges
that this should the case.
Comparisons are made with different parts of the world with the knowledge that, in commercial terms, plantations in the low
latitudes behave similarly everywhere in terms of fire causes, fire propagation factors, and characteristics of plantation
or managed mixed forest fires. A review of the fire sizes within commercial forests is a good indicator of the efficiency
of fire management strategies, and profiles from a high fire risk territory and Indonesia are compared.
Using commercial and unidentified data the author then demonstrates that commercial growers in Indonesia have a high annual
rate of forest fire loss and may also have a significant catastrophe fire exposure. This ‘cat’ exposure is far greater than
for equivalent plantations in clearly higher fire risk environments. These conclusions are and should be discussed with forestry
companies to change attitude and investment levels.
Practical points for improved plantation fire management are made along with comments about the resources required. A parallel
discussion then reviews fire risk assessment and management by the insurers to prevent their own ‘forest fire’ losses if they
are to get further involved with the provision of Indonesian commercial forest risk transfer. The explanation of how insurers
price risk within a portfolio helps identify the specific data needed for a proper risk management strategy to be developed. 相似文献
973.
Microscale Spatial Variation in Forest Litter Phytotoxicity 总被引:1,自引:0,他引:1
The spatial variation (within a 100 × 100 m plot) in the pollution of forest litter with heavy metals (Cu, Cd, Pb, and Zn), its acidity, and phytotoxicity (measured by the results of the root test using seedlings from a genetically homogeneous sample of common dandelion (Taraxacum officinale s.l.) have been estimated. Forest litter has been sampled in three zones differing in the toxic impact of long-term polymetal pollution by emissions from a copper-smelting plant emissions in the Middle Urals. The phytotoxicity variation is maximum in a moderately polluted plot, where both very high and very low pollution levels were observed, which determines a substantially nonlinear dose–effect relationship. The litter phytotoxicity is mainly accounted for by exchangeable forms of metals. Biological testing of samples from the most polluted plot has demonstrated marked antagonism between heavy metals and acidity. 相似文献
974.
对袋式除尘常用的针刺毡、基布覆膜、梯度针刺毡三类滤料进行集尘状况下压力损失冷态实验测试。结果表明:清洁滤料压力损失由大到小分别为基布覆膜滤料、梯度针刺毡、常规针刺毡;清洁滤料的压力损失与过滤速度呈正比线性变化关系,集尘后与过滤时间、粉尘负荷呈正比二次方变化关系,并通过分析给出滤料在不同集尘负荷下阻力与过滤风速、粉尘负荷间的计算关系。 相似文献
975.
A European model for waste and material flows 总被引:1,自引:1,他引:1
Frits Mller Andersen Helge Larsen Mette Skovgaard Stephan Moll Stphane Isoard 《Resources, Conservation and Recycling》2007,49(4):421-435
The use of materials and the generation of waste are linked to economic activities and in many projections these are assumed to be a constant ratio of the economic activities. This may be the case considering detailed economic activities and unchanged technology. However, the assumption of constant coefficients is questionable when linking material use and waste generation to aggregated economic activities. Therefore, in this paper, econometrics is used to test the assumption of constant waste coefficients empirically. The analyses show that an assumption of constant waste coefficients is not supported, generally, and a model allowing for trendwise changing coefficients is developed and used for projections of waste and material flows in 25 European countries. 相似文献
976.
阐述了营造生物防火林带是阻隔林火蔓延、实现"绿色防火"的主要措施,对保障森林资源安全、减少森林灾害的损失将发挥积极作用. 相似文献
977.
Reduced emissions of acidifying pollutants have changed the acidification process, and as a result, forest soils and surface
waters are slowly recovering in Sweden. However, model calculations show that some areas may never recover completely unless
further measures, such as liming, are undertaken. Liming of surface waters (lakes, rivers and wetlands) has been successfully
practised in Sweden since the 1970s, but repeated treatments are necessary. A full recovery of acidified lakes and streams
without frequent liming is however not possible until soil acidification is reversed in the most strongly affected areas.
In this study, the recovery of acidified streams was examined using ‘the total catchment approach’ i.e. treatment of both
recharge and discharge areas. The aim was to compare the quantitative effect of different treatments on run off chemistry
and the recovery of brown trout. Catchments in southwest Sweden were treated with a combination of 2 tons of wood ash and
4, 6 or 12 tons of crushed limestone per hectare in 1998/1999. Treatment of both recharge and discharge areas resulted in
fast and significant changes in stream water quality, e.g. increased concentrations of calcium, higher pH and ANC and a decreased
concentration of inorganic aluminium. The initial changes were dependent on the distribution of the applied lime between discharge
and recharge areas rather than the average dose on the total catchment. Treatment of recharge areas only, resulted in smaller
but still significant effects on calcium, pH and ANC in stream water. Furthermore, there was an initial leaching of nitrate
but it was only minor compared with the elevated leaching that occurs after a clear-cut. As a result of the treatments, brown
trout is now successfully reproducing.
Olle Westling (deceased). 相似文献
978.
979.
/ The Itapiranga Sustainable Logging Plan provides an example of how Brazil's licensing system functions for logging companies in the state of Amazonas. Two questions need to be dealt with: "How sustainable can logging in the Amazon be?" and "What and how effective are existing legal mechanisms to deal with logging projects?" The environmental impact assessment (EIA) and environmental impact statement (EIS, known as the RIMA in Brazil), present relatively detailed accounts of biodiversity and the need to adopt conservation strategies to protect it. However, social and health impacts are only superficially addressed. The economic sustainability of the operation over multiple cycles is not demonstrated. The multidisciplinary teams responsible for the EIA and EIS (RIMA) reports are hired by the project proponent, an arrangement inherently carrying the risk of biasing the result. Logging reduces biodiversity, releases greenhouse gases and inflicts social and health costs. These impacts reduce the ability of Amazonian forests to provide environmental services and to supply food and livelihood security to local populations. The reports inflate positive effects such as employment: the estimated number of jobs was cut by more than half in a revision made after the EIA and EIS (RIMA) had been approved. Not only do the reports need to be more realistic in assessing both positive and negative consequences of proposed projects, but better means are needed to ensure that promised mitigatory measures are enforced in practice. Many of the lessons that can be drawn from the Itapiranga Plan are not unique to logging projects and apply to licensing of development activites generally in Brazil and elsewhere. 相似文献
980.
I. P. Belousova K. A. Smirnov V. D. Kaz’min I. V. Kudrjavtsev 《Russian Journal of Ecology》2005,36(2):115-119
The forest ecosystem of the Orlovskoe Polese National Park has been studied in reference to the reintroduction of a rare species: the European bison (Bison bonasus L.). Preliminary data characterizing the state of forest resources and the populations of ungulates living in the forests, as well as the genetic problems associated with maintaining a viable population of the European bison, are considered.Translated from Ekologiya, No. 2, 2005, pp. 132–137.Original Russian Text Copyright © 2005 by Belousova, Smirnov, Kazmin, Kudrjavtsev. 相似文献