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461.
黑水虻转化厨余垃圾过程中病原菌灭活规律的研究与综合评价 总被引:2,自引:0,他引:2
黑水虻能够有效取食厨余垃圾等有机固体废弃物,其自身转化为昆虫蛋白和脂肪等生物质,将厨余垃圾转化为虫沙有机肥,处理过程是一种有机固体废弃物的资源化新方法.为评估黑水虻处理厨余垃圾的效率与安全性,本课题研究黑水虻在厨余垃圾处理过程中,对大肠杆菌O157:H7(EC)、鼠伤寒沙门氏菌(ST)及金黄色葡萄球(SA)的灭活能力,评价黑水虻体内的抑菌因子,分析3种病原菌对黑水虻生长增重及厨余转化效率的影响.经过18 d的黑水虻处理,研究发现:①第0和第6 d两次以6.4~7.1 log10 CFU·g-1的浓度向厨余垃圾中分别接种EC、ST和SA以后,EC经4~6 d处理被全部灭活、ST经3~4 d处理被全部灭活,SA经6 d处理,浓度下降到1.9~2.6 log10 CFU·g-1,但不能被全部灭活,病原菌的灭活效率呈现EC=ST>SA的趋势(p < 0.001),且黑水虻体内无EC、ST或SA残留;②厨余垃圾降解过程中,初期和中期pH值主要呈现酸性(4.0~5.3),对抑制EC、ST和SA起到了促进作用,后期pH值呈中性至弱碱性;③黑水虻对于EC和ST能够产生自身免疫抑制因子,且抑制活性ST>EC,但对SA无明显的免疫抑制能力,SA的灭活主要依赖于黑水虻肠道菌群的竞争性抑制作用;④黑水虻的体长、体重、预蛹率、产率,以及厨余垃圾的生物转化率和减量化率未受病原菌存在的影响,18 d后EC组、ST组和SA组的预蛹率均达到在80%以上,厨余减量化率分别达到74.0%、79.1%和78.5%,生物转化率分别达到13.0%、13.2%、19.4%.综上,黑水虻能够在彻底灭活EC、ST,99%灭活SA的同时,高效降解厨余垃圾(减量化率>74%),并转化为虫体有机质(虫产率>10%),是一种高效卫生的厨余垃圾资源化方法.今后的研究中,还需要加强以金葡菌为代表的抗逆性病原菌的灭活机制的探讨. 相似文献
462.
A multinational collaborative study during the summer of 1983 addressed organizational alternatives in natural systems management. Participants were particularly interested in ways different governments attempted to resolve the disparity between the interconnected quality of nature and the compartmentalized structure of bureaucracies. Five patterns of organization have evolved to meet this challenge: mission agencies managing ecosystems; independent or interagency central environmental units: environmental units within mission agencies; environmental components within central planning units; and regional superagencies. The systems developed by five nations—the United States, Korea, Malaysia, the Philippines, and Thailand—are analyzed and compared in terms of these five patterns. 相似文献
463.
Leonard Ortolano 《Environmental Impact Assessment Review》1985,5(1):9-35
LEONARD ORTOLANO has written a textbook, Environmental Planning and Decision Making, that is ideal for introducing undergraduates to the field of environmental planning. His three chapters on environmental impact assessment (from 16 chapters overall) present a range of impact assessment methods in a helpful decision-making context. Specific techniques for considering biological factors in planning, evaluating the visual qualities of the environment, assessing noise impacts, assessing air quality impacts, and assessing impacts on water resources are also covered in five additional chapters. Professional planners and engineers should find this introduction to the approaches employed by specialists of various kinds helpful. With the permission of the publisher, John Wiley and Sons, we here reprint Chapter 15, “Estimating Air Quality Impacts,” from Ortolano's excellent book. This straightforward presentation of a six-step process for establishing the air quality impacts of proposed development projects is a model of clarity. 相似文献
464.
湿地土壤有机碳及其活性组分分布特征影响因素研究 总被引:1,自引:0,他引:1
红碱淖湖泊湿地是西北半干旱荒漠区重要的生态屏障,随着湖泊面积的减少以及土壤退化程度的加剧,逐渐形成5种典型的景观类型(盐碱沼泽、沼泽化草甸、草地、草原化沙地、沙地)。基于野外实地调查,选取红碱淖湖泊湿地流域蟒盖兔和尔林兔2个典型子流域,研究湖泊退化后不同景观类型土壤有机碳及其活性组分的分布特征及其影响因素。结果表明,5种景观类型土壤有机碳(SOC)、土壤可溶性有机碳(DOC)、土壤易氧化态有机碳(EOC)含量均较低。土壤SOC和EOC在垂直剖面上分布特征一致,土壤EOC与土壤有机质动态变化密切相关,土壤砂砾含量高是研究区土壤有机碳含量较低的主要原因。 相似文献
465.
Protected areas’ chief conservation objectives are to include species within their boundaries and protect them from negative external pressures. Many protected areas are not achieving these goals, perhaps in part due to land development inside and outside protected areas. We conducted spatial analyses to evaluate the ability of Canadian protected areas to mitigate the effects of nearby land development. We investigated correlations of national patterns of land development in and around protected areas and then examined national patterns of roads, urban area, and croplands in protected areas. We calculated the amount of developed land in protected areas and within 25–100 km of protected‐area borders, the density of roads, and extent of urban and cropland area in protected areas. We constructed logistic‐regression models to test whether development in a protected area was associated with landscape and protected‐area characteristics. Land development was far less extensive inside than outside protected areas. However, several protected areas, particularly small southern areas near small urban centers had substantial development inside their boundaries, and nearly half of protected areas had roads. The cumulative extent of development within 50 km of protected areas was the best predictor of the probability of land development in protected areas. Canadian First Nations, industries, government, and nongovernmental organizations are currently planning an unprecedented number of new protected areas. Careful management of areas beyond protected‐area boundaries may prove critical to meeting their long‐term conservation objectives. Desarrollo de Tierras Dentro y Alrededor de Áreas Protegidas en la Frontera Silvestre 相似文献
466.
FRANCISMÁRIO F. SANTOS LADISLAU MARTIN-NETO FLAVIA PEREIRA SILVA AIROLDI MARIA O. O. REZENDE 《Journal of environmental science and health. Part. B》2013,48(5):721-730
This paper reports the effect of ultraviolet radiation on the degradation of pesticide ethyl parathion in the presence of humic acids. Ethyl parathion was completely degraded in 300 min using an artificial lamp of 7.41 × 10? 10 einstein/s. Humic acid from peat did not influence the photochemical rate (k = 8.92 × 10?3 min). However, in the presence of aquatic humic acid, the photochemical rate was higher (11.5 × 10?3 min). The analytical determinations show the presence of p-nitrophenol and aminophenol in the reaction medium during the photochemical experiments. The kinetic of degradation in all experiments obeyed a first-order reaction pattern. 相似文献
467.
Models to Assess the Risk of Snow and Wind Damage in Pine, Spruce, and Birch Forests in Sweden 总被引:2,自引:0,他引:2
3 are damaged annually by snow and wind, roughly corresponding to a value of US$150 million, and in Europe, the damage amounts
to hundreds of millions of US dollars each year. To help to reduce these losses, tools for risk assessment within forest management
have been developed. Predictions were developed of the risk of damage from snow and wind to Scots pine (Pinus sylvestris L.), Norway spruce [Picea abies (L.) Karst.] and Birch (Betula spp. L.) plots using tree, stand, and site characteristics. The data were obtained from 6756 permanent sample plots within
the Swedish National Forest Inventory, which were inventoried twice at five-year intervals between 1983 and 1992. Input data
for model development used measurements from the first inventory of tree characteristics for the largest sample tree, stand,
and site data, and records of snow and wind damage from the second inventory. Models were developed for three different regions
for pine- and spruce-dominated sites, while models for the whole country were developed for birch sites. In general the estimated
proportion of damaged plots was highly overestimated (31.7%–56.2%), compared with the observed proportion of 3.4%–11.9%. The
models for Norway spruce comprising tree, stand, and site data show the best predictability of damaged plots, with 60.6%–67.6%
of plots correctly classified. It is concluded that the models developed can be used to detect sites with a high probability
of damage from snow and wind, and thus be used as tools to reduce future damage and costs in practical forestry. 相似文献
468.
469.
Lessons from Białowieża Forest on the history of protection and the world's first reintroduction of a large carnivore
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Tomasz Samojlik Nuria Selva Piotr Daszkiewicz Anastasia Fedotova Adam Wajrak Dries Pieter Jan Kuijper 《Conservation biology》2018,32(4):808-816
Understanding how the relationships between large carnivores and humans have evolved and have been managed through centuries can provide relevant insights for wildlife conservation. The management history of many large carnivores has followed a similar pattern, from game reserved for nobility, to persecuted pests, to conservation targets. We reconstructed the history of brown bear (Ursus arctos) management in Bia?owie?a Forest (Poland and Belarus) based on a detailed survey of historical literature and Russian archives. From the end of the Middle Ages to the end of 18th century, the brown bear was considered “animalia superiora” (i.e., game exclusively reserved for nobility and protected by law). Bears, also a source of public entertainment, were not regarded as a threat. Effective measures to prevent damages to traditional forest beekeeping were already in practice. In the beginning of 19th century, new game‐management approaches allowed most forest officials to hunt bears, which became the primary target of hunters due to their valuable pelt. This, together with an effective anticarnivore policy enhanced by bounties, led to bear extirpation in 1879. Different approaches to scientific game management appeared (planned extermination of predators and hunting levels that would maintain stable populations), as did the first initiatives to protect bears from cruel treatment in captivity. Bear reintroduction in Bia?owie?a Forest began in 1937 and represented the world's first reintroduction of a large carnivore motivated by conservation goals. The outbreak of World War II spoiled what might have been a successful project; reproduction in the wild was documented for 8 years and bear presence for 13. Soft release of cubs born in captivity inside the forest but freely roaming with minimal human contact proved successful. Release of captive human‐habituated bears, feeding of these bears, and a lack of involvement of local communities were weaknesses of the project. Large carnivores are key components of ecosystem‐function restoration, and site‐specific histories provide important lessons in how to preserve them for the future. 相似文献
470.
In an analytical model of symmetric countries with mobile capital and local or transboundary pollution we investigate whether competition in emissions taxes (or emissions caps) and capital taxes leads to efficient outcomes when governments act strategically. When they have capital taxes and emissions caps at their disposal, they refrain from taxing capital and set their caps inefficiently lax [efficient] for transboundary [local] pollution. When they have the option to tax capital and emissions, capital is subsidized [untaxed] and emissions taxes are inefficiently low [efficient] for transboundary [local] pollution. In case of transboundary pollution emissions caps are Pareto-superior to emissions taxes. That holds regardless of whether the environmental policy is applied as stand-alone policy or combined with capital tax competition. 相似文献