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271.
Science guides search and rescue after the 2006 Philippine landslide   总被引:1,自引:0,他引:1  
A rockslide-debris avalanche destroyed the remote village of Guinsaugon in Southern Leyte, Philippines, on 17 February 2006. Although search and rescue procedures were implemented immediately, the scale of the landslide and a lack of information about its nature resulted in unfocused and imprecise efforts in the early days of the operation. Technical support was only introduced five days after the event, provided by a team of volunteer geologists, geophysicists, and meteorologists. By the time search and rescue operations were transferred to specific target sites, however, the chances of finding survivors trapped under the rubble had diminished. In such critical situations, speed, accuracy, and the maximum appropriation of resources are crucial. We emphasise here the need for a systematic and technically informed approach to search and rescue missions in large-scale landslide disaster contexts, and the formulation of better disaster management policies in general. Standard procedures must be developed and enforced to improve how civil authorities respond to natural calamities.  相似文献   
272.
Slurry-phase biodegradation of weathered oily sludge waste   总被引:3,自引:0,他引:3  
We assessed the biodegradation of a typical oily sludge waste (PB401) in Mexico using several regimes of indigenous microbial consortium and relevant bioremediation strategies in slurry-phase system. Abiotic loss of total petroleum hydrocarbons (TPH) in the PB401 was insignificant, and degradation rates under the various treatment conditions ranged between 666.9 and 2168.7 mg kg(-1) day(-1) over a 15 days reaction period, while viable cell count peaked at between log(10)5.7 and log(10)7.4 cfu g(-1). Biostimulation with a commercial fertilizer resulted in 24% biodegradation of the TPH in the oily waste and a corresponding peak cell density of log(10)7.4 cfu g(-1). Addition of non-indigenous adapted consortium did not appear to enhance the removal of TPH from the oily waste. It would appear that the complexities of the components of the alkylaromatic fraction of the waste limited biodegradation rate even in a slurry system.  相似文献   
273.
The concentrations of arsenic, cadmium, chromium, copper, mercury, nickel, lead and zinc in surface sediments collected from the east coast of peninsular Malaysia, along the South China Sea, were measured by two methods instrumental neutron activation analysis and inductively coupled plasma mass spectroscopy. The obtained results were use to determine the areal distribution of the metals of in the east coast of peninsular Malaysia and potential sources of these metals to this environment. The geochemical data propose that most of the metals found in the east coast of peninsular Malaysia constitute a redistribution of territorial materials within the ecosystem. Then, the metal concentrations can be considered to be present at natural background levels in surface sediments.  相似文献   
274.
275.
The behaviour of six phthalate esters in the presence of particulate material suspended in fresh and saline water has been examined. The adsorption of all phthalates by the particulates is enhanced by the presence of salt. The adsorption process is fairly rapid ( <2-3 h) and the degree of adsorption depends on the characteristics of the particulates. Di-ethylhexyl phthalate is adsorbed most actively by material of a small particle size. The adsorption of other phthalates is more strongly influenced by the chemical composition of the particulates and is most closely correlated with their lipid content.  相似文献   
276.
The orb-weaving spider Nephila edulis incorporates into its web a band of decaying animal and plant matter. While earlier studies demonstrate that larger spiders utilise these debris bands as caches of food, the presence of plant matter suggests additional functions. When organic and plastic items were placed in the webs of N. edulis, some of the former but none of the latter were incorporated into the debris band. Using an Y-maze olfactometer, we show that sheep blowflies Lucilia cuprina are attracted to recently collected debris bands, but that this attraction does not persist over time. These data reveal an entirely novel foraging strategy, in which a sit-and-wait predator attracts insect prey by utilising the odours of decaying organic material. The spiders habit of replenishing the debris band may be necessary to maintain its efficacy for attracting prey.  相似文献   
277.
本文运用系统生态学的系统分析方法,从能量流动、物质循环方面,以黑龙江省庆安县六合村为典型,对我国东北松嫩平原漫川漫岗农业系统生态农业建设前后进行分析比较研究。分析结果表明,六合村的生态农业建设为松嫩平原农业生态系统的改善,经济水平较低地区的农业发展提供了有益的经验。通过合理调整系统内的能量流及物质环循,在提高系统生产力的同时,保护农业生态环境。  相似文献   
278.
Ozone stress has become an increasingly significant factor in cases of forest decline reported throughout the world. Current metrics to estimate ozone exposure for forest trees are derived from atmospheric concentrations and assume that the forest is physiologically active at all times of the growing season. This may be inaccurate in regions with a Mediterranean climate, such as California and the Pacific Northwest, where peak physiological activity occurs early in the season to take advantage of high soil moisture and does not correspond to peak ozone concentrations. It may also misrepresent ecosystems experiencing non-average climate conditions such as drought years. We compared direct measurements of ozone flux into a ponderosa pine canopy with a suite of the most common ozone exposure metrics to determine which best correlated with actual ozone uptake by the forest. Of the metrics we assessed, SUM0 (the sum of all daytime ozone concentrations > 0) best corresponded to ozone uptake by ponderosa pine, however the correlation was only strong at times when the stomata were unconstrained by site moisture conditions. In the early growing season (May and June). SUM0 was an adequate metric for forest ozone exposure. Later in the season, when stomatal conductance was limited by drought. SUM0 overestimated ozone uptake. A better metric for seasonally drought-stressed forests would be one that incorporates forest physiological activity, either through mechanistic modeling, by weighting ozone concentrations by stomatal conductance, or by weighting concentrations by site moisture conditions.  相似文献   
279.
This paper reviews the regulatory history for nitrogen oxides (NOx) pollutant emissions from stationary sources, primarily in coal-fired power plants. Nitrogen dioxide (NO2) is one of the six criteria pollutants regulated by the 1970 Clean Air Act where National Ambient Air Quality Standards were established to protect public health and welfare. We use patent data to show that in the cases of Japan, Germany, and the United States, innovations in NOx control technologies did not occur until stringent government regulations were in place, thus "forcing" innovation. We also demonstrate that reductions in the capital and operation and maintenance (O&M) costs of new generations of high-efficiency NOx control technologies, selective catalytic reduction (SCR), are consistently associated with the increasing adoption of the control technology: the so-called learning-by-doing phenomena. The results show that as cumulative world coal-fired SCR capacity doubles, capital costs decline to approximately 86% and O&M costs to 58% of their original values. The observed changes in SCR technology reflect the impact of technological advance as well as other factors, such as market competition and economies of scale.  相似文献   
280.
Nine samples of butter from producers in various states of Australia were analysed for polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). Detectable concentrations of 2,3,7,8-chlorine substituted PCDD/Fs were found in all samples. The mean PCDD/F concentration expressed as 2,3,7,8-TCDD equivalents (TEQs) was 0.19 pg TEQ g-1 fat. The highest concentration (0.46 pg TEQ g-1 fat) was observable in a sample from Victoria which is the most densely populated state. Overall the results indicate that PCDD/F concentrations in dairy products from Australia are low in comparison to the levels in dairy products of industrialized countries on the Northern Hemisphere. As expected, this study provides evidence that the environmental and consequently the human body burden of PCDD/Fs to be relatively low in Australia.  相似文献   
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