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331.
It is widely recognized that our social and moral environments influence our actions and belief formations. We are never fully immune to the effects of cultural membership. What is not clear, however, is whether these influences excuse average moral agents who fail to scrutinize conventional norms. In this paper, I argue that the lack of extensive public debate about factory farming and, its corollary, extreme animal suffering, is probably due, in part, to affected ignorance. Although a complex phenomenon because of its many manifestations, affected ignorance is morally culpable because it involves a choice not to investigate whether some practice in which one participates in might be immoral. I contend further that James Montmarquet’s set of intellectual virtues can provide a positive account of what it means to act as a responsible moral agent while immersed in a meat eating culture; they also represent the moral and epistemic framework for the kind of public discourse that should be taking place.  相似文献   
332.
中国本土鱼类模式生物稀有鮈鲫研究应用的历史与现状   总被引:1,自引:0,他引:1  
稀有鮈鲫(Gobiocypris rarus)是一种中国特有的小型鲤科鱼类,从1990年开始,中国科学院水生生物研究所以培育新的实验鱼为目的,对稀有鮈鲫开展了系列的实验动物化研究,并推动其在各研究领域中的应用。随着我国化学品环境管理制度的建立,稀有鮈鲫已逐渐成为我国化学品测试中最重要的受试鱼类。本文综述了稀有鮈鲫分类地位、分布、形态特征、早期发育、生长、繁殖、遗传、对环境的适应性等方面的生物学特点,分析了稀有鮈鲫作为模式生物的优点,介绍了稀有鮈鲫实验动物标准制定进展。随着实验动物标准化工作的深入以及基因组测序工作的开展,稀有鮈鲫将更广泛地应用于相关的研究和检定,成为一种我国具有代表性的本土模式生物。  相似文献   
333.
The goal of this study was to optimize the mixture of swine manure (SM) and cattle manure (CM) used in the vermicomposting process, seeking to increase the manure biodegradation rate and enhance the biomass production of both earthworms and higher plants. To achieve this goal, physico-chemical parameters were determined to assess the final compost quality after 50 days of vermicomposting. The different manure ratios used to produce the composts (C) were as follows (SM:CM, % m/m basis): C1 100:0, C2 (75:25), C3 (50:50), C4 (25:75), and C5 (0:100). In addition, the earthworm biomass and the phytoproductivity of lettuce (Lactuca sativa L.) plants grown in mixtures (1:1) of natural soil and the most viable vermicomposts were investigated. The C1 and C2 compost compositions were associated with high earthworm mortality rates. The C3 compost provided the highest mineral concentrations and C5 showed the highest lettuce yield (wet biomass). The results verify that stabilized cattle manure is an excellent substrate for the vermicomposting process and that fresh swine manure must be mixed with pre-stabilized cattle manure to ensure an optimized vermicomposting process, which must be controlled in terms of temperature and ammonia levels. It is concluded that small livestock farmers could add value to swine manure by applying the vermicomposting process, without the need for high investments and with a minimal requirement for management of the biodegradation process. These are important technical aspects to be considered when circular economy principles are applied to small farms.  相似文献   
334.
目前我国正在修改《野生动物保护法》,其中一些热点问题引发社会讨论。建议在立法目的方面,可规定保护栖息地、规范野生动物资源利用和维护生物多样性。在保护对象方面,采用重点保护与一般保护相结合,改变"三有"的归类标准,扩大栖息地的保护范围。在驯养繁殖方面,明确"科学驯养繁殖"的方针,制定名录规范人工繁育和综合利用,保护动物福利,实行科学野化放归。在社会治理方面,明确信息公开和公众参与原则,拓宽公众参与渠道,建立基金,赋予社会组织提起公益诉讼的权利,发挥产业协会的自律作用。在法律责任方面,进一步明确消费者和监管者的责任,增加违法行为的种类,加大处罚力度,重点监管网络市场,建立野生动物致害补偿基金。  相似文献   
335.
This study sought to evaluate the potential of trees planted around commercial poultry farms to trap ammonia (NH3), the gas of greatest environmental concern to the poultry industry. Four plant species (Norway spruce, Spike hybrid poplar, Streamco willow, and hybrid willow) were planted on eight commercial farms from 2003 to 2004. Because temperature (T) can be a stressor for trees, T was monitored in 2005 with data loggers among the trees in front of the exhaust fans (11.4 to 17.7 m) and at a control distance away from the fans (48 m) during all four seasons in Pennsylvania. Norway spruce (Picea abies) foliage samples were taken in August 2005 from one turkey and two layer farms for dry matter (DM) and nitrogen (N) analysis. The two layer farms had both Norway spruce and Spike hybrid poplar (Populus deltoides × Populus nigra) plantings sampled as well allowing comparisons of species and the effect of plant location near the fans versus a control distance away. Proximity to the fans had a clear effect on spruce foliar N with greater concentrations downwind of the fans than at control distances (3.03 vs. 1.88%; P ≤ 0.0005). Plant location was again a significant factor for foliar N of both poplar and spruce on the two farms with both species showing greater N adjacent to the fans compared to the controls (3.75 vs. 2.32%; P ≤ 0.0001). Pooled foliar DM of both plants was also greater among those near the fans (56.17, fan vs. 44.67%, control; P ≤ 0.005). Species differences were also significant showing the potential of poplar to retain greater foliar N than spruce (3.52 vs. 2.55%; P ≤ 0.001) with less DM (46.00 vs. 54.83%; P ≤ 0.05) in a vegetative buffer setting. The results indicated plants were not stressed by the T near exhaust fans with mean seasonal T (13.04 vs. 13.03°C, respectively) not significantly different from controls. This suggested poultry house exhaust air among the trees near the fans would not result in dormancy stressors on the plants compared to controls away from the fans.  相似文献   
336.
This study evaluated the potential of trees planted around commercial poultry farms to trap ammonia (NH3) and dust or particulate matter (PM). Norway spruce, Spike hybrid poplar, hybrid willow, and Streamco purpleosier willow were planted on five commercial farms from 2003 to 2004. Plant foliage was sampled in front of the exhaust fans and at a control distance away from the fans on one turkey, two laying hen, and two broiler chicken farms between June and July 2006. Samples were analyzed for dry matter (DM), nitrogen (N), and PM content. In addition, NH3 concentrations were measured downwind of the exhaust fans among the trees and at a control distance using NH3 passive dosi–tubes. Foliage samples were taken and analyzed separately based on plant species. The two layer farms had both spruce and poplar plantings whereas the two broiler farms had hybrid willow and Streamco willow plantings which allowed sampling and species comparisons with the effect of plant location (control vs. fan). The results showed that NH3 concentration h? 1 was reduced by distance from housing fans (P ≤ 0.0001), especially between 0 m (12.01 ppm), 11.4 m (2.59 ppm), 15 m (2.03 ppm), and 30 m (0.31 ppm). Foliar N of plants near the fans was greater than those sampled away from the fans for poplar (3.87 vs. 2.56%; P ≤ 0.0005) and hybrid willow (3.41 vs. 3.02%; P ≤ 0.05). The trends for foliar N in spruce (1.91 vs. 1.77%; P = 0.26) and Streamco willow (3.85 vs. 3.33; P = 0.07) were not significant. Pooling results of the four plant species indicated greater N concentration from foliage sampled near the fans than of that away from the fans (3.27 vs. 2.67%; P ≤ 0.0001). Foliar DM concentration was not affected by plant location, and when pooled the foliar DM of the four plant species near the fans was 51.3% in comparison with 48.5% at a control distance. There was a significant effect of plant location on foliar N and DM on the two layer farms with greater N and DM adjacent to fans than at a control distance (2.95 vs. 2.15% N and 45.4 vs. 38.2% DM, respectively). There were also significant plant species effects on foliar N and DM with poplar retaining greater N (3.22 vs. 1.88%) and DM (43.7 vs. 39.9%) than spruce. The interaction of location by species (P ≤ 0.005) indicated that poplar was more responsive in terms of foliar N, but less responsive for DM than spruce. The effect of location and species on foliar N and DM were not clear among the two willow species on the broiler farms. Plant location had no effect on plant foliar PM weight, but plant species significantly influenced the ability of the plant foliage to trap PM with spruce and hybrid willow showing greater potential than poplar and Streamco willow for PM2.5(0.0054, 0.0054, 0.0005, and 0.0016 mg cm? 2; P ≤ 0.05) and total PM (0.0309, 0.0102, 0.0038, and 0.0046 mg cm? 2, respectively; P ≤ 0.001). Spruce trapped more dust compared to the other three species (hybrid willow, poplar, and Streamco willow) for PM10 (0.0248 vs. 0.0036 mg cm? 2; P ≤ 0.0001) and PM> 10 (0.0033 vs. 0.0003 mg cm? 2; P = 0.052). This study indicates that poplar, hybrid willow, and Streamco willow are appropriate species to absorb poultry house aerial NH3–N, whereas spruce and hybrid willow are effective traps for dust and its associated odors.  相似文献   
337.
A survey was carried out from 2008 to 2010 to determine the concentrations of 16 organochlorine pesticide residues (OPRs) from Tizayuca, Hidalgo, Mexico. Organochlorine residue determinations were made from milk fat, using chromatographic cleanup and analysis by gas chromatography with an electron capture detector. The OPR concentrations found were from below the detection limit (DL) to 0.91 ng g?1 in 2008, DL to 0.38 ng g?1 in 2009 and DL to 0.59 ng g?1 in 2010. In general concentrations of organochlorine pesticides were higher in the wet season (3.37 ng g?1 and 4.79 ng g?1) than the dry season (1.92 ng g?1 and 2.71 ng g?1) for 2009 and 2010, due to control of pests in the pasture and sheds. According to Codex Alimentarius regulations, individual pesticides did not exceed the permissible limits, which for example were 10 μg kg?1 for alpha hexachlorocyclohexane (HCH) and endosulfan I, 20 μg kg?1 for p,p’-DDT, and 6 μg kg?1 for dieldrin, endrin and heptachlor. A reduction of organochlorine pesticide concentrations in cow's milk was noted, indicating that the Mexican government has achieved reduction or elimination of some organochlorine pesticides in response to global agreements on persistent organic pollutants.  相似文献   
338.
The loss of large animals due to overhunting and habitat loss potentially affects tropical tree populations and carbon cycling. Trees reliant on large-bodied seed dispersers are thought to be particularly negatively affected by defaunation. But besides seed dispersal, defaunation can also increase or decrease seed predation. It remains unclear how these different defaunation effects on early life stages ultimately affect tree population dynamics. We reviewed the literature on how tropical animal loss affects different plant life stages, and we conducted a meta-analysis of how defaunation affects seed predation. We used this information to parameterize models that altered matrix projection models from a suite of tree species to simulate defaunation-caused changes in seed dispersal and predation. We assessed how applying these defaunation effects affected population growth rates. On average, population-level effects of defaunation were negligible, suggesting that defaunation may not cause the massive reductions in forest carbon storage that have been predicted. In contrast to previous hypotheses, we did not detect an effect of seed size on changes in seed predation rates. The change in seed predation did not differ significantly between exclosure experiments and observational studies, although the results of observational studies were far more variable. Although defaunation surely affects certain tree taxa, species that benefit or are harmed by it and net changes in forest carbon storage cannot currently be predicted based on available data. Further research on how factors such as seed predation vary across tree species and defaunation scenarios is necessary for understanding cascading changes in species composition and diversity.  相似文献   
339.
长江三角洲城郊畜禽粪便的污染负荷及其防治对策   总被引:102,自引:0,他引:102  
长江三角洲是我国经济最发达的地区之一,随着经济的高速发展,区内地表水环境迅速趋于恶化。研究发现,畜禽粪便流失污染地表水的现象已成为本区郊县(区)最大的有机污染源和最引入注目的非点源污染问题之一。以地处长江三角洲地区的上海、苏锡常、杭嘉湖和宁绍地区为例,结合当地畜禽饲养量,采用各类畜禽的粪便及其污染物的排泄系数,估算了畜禽粪便的污染负荷当量。从现行的政策法规、饲养基地的布局和利用情况等方面分析了近年来本区畜禽污染严重的原因。提出要加强畜禽粪便的综合治理力度,制订畜牧业污染防治法,完善和配套畜禽粪便的综合治理设施,实现畜禽粪便的资源化、减量化、无害化和生态化,形成布局合理、设施先进、清洁生产、达标排放的长江三角洲畜牧业生产新格局。  相似文献   
340.
The waste gas evolved from biodegradation of animal urine contains ammonia causing environmental concerns. A new and effective method for removing ammonia from such waste gas using reactive adsorption is presented. In the process, activated carbon impregnated with H2SO4(H2SO4/C) is employed. Ammonia in the waste gas reacts with H2SO4 on the adsorbent instantaneously and completely to form (NIL)2SO4. The H2SO4/C adsorbent is high in NH3 adsorption capacity and regenerable. The NH3 removal capacity of this regenerable adsorbent is more than 30 times that of the adsorbents used normally in the industry. The spent H2SO4/C is regenerated by flowing low-pressure steam through the adsorbent bed to remove the (NH4)2SO4 from the adsorbent. The regeneration by-product is concentrated (NH4)2SO4 solution, which is a perfect liquid fertilizer for local use. Re-soaking the activated carbon with H2SO4 solution rejuvenates the activity of the adsorbent. Thus the H2SOJC can be reused repeatedly. In the mechanism of this reactive adsorption process, trace of H20 in the waste gas is a required, which lends itself to treating ammonia gas saturated with moisture from biodegradation of animal urine.  相似文献   
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