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1.
灾害区划研究的现状,存在问题与发展趋势   总被引:4,自引:0,他引:4  
着重分析了灾害区划的现状、存在问题和发展趋势,对灾害区划的目标、原理、方法、类型及指标体系进行了深入探讨。  相似文献   
2.
随着风力发电技术的不断发展,风力发电已成为我国重点发展的可再生能源产业。而作为用源大户的电力行业在低碳经济中占有重要地位。由于风能具有无污染,可再生,蕴量巨大等优点,发展和利用风能等可再生资源已经成为国际电力发展的大趋势,所以风能发电在未来必然会具有广阔的前景。本文就风力发电现状及未来趋势进行探索。  相似文献   
3.
Since 1972, at the University of Hohenheim in Stuttgart, Germany, airborne particulate matter (PM12 and then PM10) was continuously collected on filters and analyzed for environmentally relevant elements by X-ray fluorescence analysis. The resulting long-term time series are suitable for the investigation of trends and of seasonal variation. For the period 1972-2005, monthly and annual concentration mean values of 13 elements (Br, Ca, Cr, Cu, Fe, K, Mn, Ni, Pb, S, Ti, V, and Zn) in the air are presented. Trend curves were fitted and the mean yearly variation of the concentration for these elements was calculated and represented graphically. All trend curves show a diminution of the air pollution during this period, but to different extents. Mean trends in percent per year were calculated for each element both for the entire investigation period and for three data subsets of 10-11 years. Possible explanations are discussed in detail.  相似文献   
4.
We assessed satellite derived tropospheric NO2 distribution on a global scale and identified the major NO2 hotspot regions. Combined GOME and SCIAMACHY measurements for the period 1996-2006 have been used to compute the trends over these regions. Our analysis shows that tropospheric NO2 column amounts have increased over the newly and rapidly developing regions like China (11 ± 2.6%/year), south Asia (1.76 ± 1.1%/year), Middle East (2.3 ± 1%/year) and South Africa (2.4 ± 2.2%/year). Tropospheric NO2 column amounts show some decrease over the eastern US (−2 ± 1.5%/year) and Europe (0.9 ± 2.1%/year). We found that although tropospheric NO2 column amounts decreased over the major developed regions in the past decade, the present tropospheric NO2 column amounts over these regions are still significantly higher than those observed over newly and rapidly developing regions (except China). Tropospheric NO2 column amounts show some decrease over South America and Central Africa, which are major biomass burning regions in the Southern Hemisphere.  相似文献   
5.

Problem

Between 1992 and 2005, 1412 workers on farms died from tractor overturns. A Rollover Protective Structure (ROPS) is a proven intervention to reduce overturn deaths. However, farm characteristics that are associated with the adoption of ROPS are not well understood.

Methods

ROPS prevalence statistics were derived from National Institute for Occupational Safety and Health (NIOSH) surveys that tracked ROPS use on farms. Data were from the years 1993, 2001, and 2004.

Results

In 1993, 38% of tractors were equipped with ROPS. This increased to 51% by 2004. ROPS prevalence rates were higher on farms in the Southern region of the United States, on farms where the operator was 25-34 years old, and on farms with $100,000 or more of farm sales. Low ROPS prevalence rates were associated with farm operators 65 years old or older and with farms with less than $10,000 of farm product sales.

Summary

The increase in ROPS prevalence between 1993 and 2004 has not been sufficient to decrease the rate of tractor overturn deaths on farms. Incentive programs targeting older farm operators and low-income farm operations are suggested to increase ROPS use on tractors.

Impact on Industry

The study provides farm characteristics associated with low ROPS prevalence rates. The results can be used to target farms for future ROPS promotion activities.  相似文献   
6.
If global warming is accelerating, then one might expect temperatures for most stations to be accelerating and perhaps variability to be increasing. In this study, we examine 57 New Zealand temperature time series for evidence of non-linearity and changing variability. These correspond to time series for annual minima, annual means and annual maxima for 19 stations. Estimation is by an extended least-squares method. We find a surprising diversity of behaviour of these series – presumably reflecting their different geographic factors as well as series length. We give evidence of regions where temperatures are decreasing. For series where a linear trend is significant, it is downwards in about one third of the cases. This proportion was higher in the South Island, especially for series of minima. Where a non-linear trend is significant, temperatures are decelerating in about one half of the cases. The ratio of downward to upward trends is highest among annual maxima and South Island minima and smallest in annual means. Where a linear trend in the variability is significant, it is decreasing in 13 cases and increasing in 5 cases, although possibly this is partly due to poorer quality data last century. Where a non-linear trend in the variability is significant, variability is decelerating in about two thirds of the cases. The results are used to project upper and lower return levels of minima, means and maxima for each of the series to the year 2010.  相似文献   
7.
环境监测能力建设与仪器支撑   总被引:6,自引:5,他引:1  
在总结我国环境监测技术和仪器发展的基础上,从"十二五"环境监测工作发展的需要,阐明了我国环境监测技术和监测仪器存在的问题以及未来的发展趋势。  相似文献   
8.
There is limited knowledge of the mechanisms that can inspire people's concern and engagement in the protection of unpopular and unappealing species. We analyzed Polish people's interest in themed internet memes featuring the proboscis monkey (Nasalis larvatus) and the consequences of this interest for conservation marketing. We examined Google Trends data, used Google Search, and searched popular media materials to estimate interest in the proboscis monkey in Poland. Photos of the proboscis monkey when presented with humor in internet memes attracted as much interest as usually more popular species (e.g., koala, panda, and orangutan) used in marketing by nongovernmental organizations. Amusing internet memes spread by social media positively correlated with increasing interest in the unappealing species, such as proboscis monkey. Interest in amusing internet memes positively correlated with individuals’ decisions to donate to 6 crowdfunding actions. Thus, conservation marketing that includes amusing memes and social media may provide a worthwhile complement to traditional campaigns and are likely to influence individuals who are unaffected by the usual means.  相似文献   
9.
Our world is largely dependent upon the forestry productions. Through the exploitation of forest reserves, we manufacture various industrial products, furniture, and obtain fuel and energy. Forestry productions should be conducted without large-scale deforestation and environmental degradation. In present study we perform a review and forecast analysis on forestry productions worldwide, with the objectives of providing an insight into the trend for several types of forestry productions in the future, and providing referential data for sustainable forestry productions and environmental management. Polynomial functions are used to fit trajectories of forestry productions since 1961 and forecasts during the coming 20 years are given in detail. If the past pattern continues, world fibreboard production would dramatically grow and reach 224,300,000 ± 44,400,000 m3 by the year 2020, an increase up to 240.7 to 408.9% as compared to the present level. Roundwood production of the world would change by −55.5 to 70.4% and reach 3,526,600,000 ± 2,066,800,000 m3 by 2020. In 2020 world production of sawlogs and veneer logs would change by −100 to 164.6% and reach 1,212,900,000 ± 1,242,600,000 m3. Global wood fuel production would change by −68.9 to 1.4% and reach 1,130,900,000 ± 600,800,000 m3 by 2020. Forestry productions in developed countries would largely surpass productions in developing countries in the near future. World forestry production grew since 1961 excluding wood fuel. Roundwood and wood fuel account for the critical proportions in the forestry productions. Wood fuel production has being declined and rapid growing of roundwood production has slowed in recent years. Widespread use of regenerative wood substitutes and worldwide afforestation against deforestation will be among the most effective ways to reduce deforestation and environment degradation associated with forestry productions.  相似文献   
10.
We analyze trends of some nitrogen compounds using long-term measurements and results from the EMEP (co-operative programme for monitoring and evaluation of the long-range transmissions of air pollutants in Europe) chemical transport model at EMEP sites. We find statistically significant declines at the majority of sites for NH(x) (sum of ammonia and ammonium) in air and for nitrate and ammonium in precipitation, but only at a few sites for xNO3 (sum of nitrate and nitric acid) in air. Model calculations and measurements give similar results. We demonstrate that the lack of trends for xNO3 in air at least partly can be attributed to a shift in the equilibrium between nitric acid and ammonium nitrate towards particulate phase, caused by reductions in the sulfur dioxide emissions.  相似文献   
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