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81.
大伙房水库上游禽畜业污染现状及其防治对策   总被引:1,自引:0,他引:1  
为了保护大伙房水库 ,控制水库上游禽畜养殖业污染 ,对禽畜养殖业污染现状进行了调查 ,估算了禽畜粪尿的流失量。结果表明 ,一头猪日排泄粪尿量约是人排粪尿的 5倍。水库上游禽畜养殖业污染负荷已超过水库上游生活污水的污染负荷 ,成为了水库上游地区主要的有机物污染源。对此 ,提出了控制禽畜业污染的对策和建议。  相似文献   
82.
Variations in land requirements for meat production   总被引:2,自引:0,他引:2  
Production of meat requires substantial amounts of feed grains which in turn require vast amounts of land. Future population growth and increase in consumption will raise the demand for meat and with it the land required for meat production. This paper analyses the various factors that affect land requirements for meat production. Meat production by Dutch broilers, pigs and beef cattle on their current feeds are compared and options for change are evaluated with respect to their nutritional needs. Differences in land requirements of a factor of 3 were found between different agricultural production systems and feeds as well as between types of livestock. It is shown that broilers have the lowest land requirement while beef cattle have the highest. The variation in feed crop yields between agricultural systems is discussed. It is concluded that due to the large variation within the system there is potential for reduction in the land requirements for meat production.  相似文献   
83.
Can animals, and especially cattle, be the subject ofmoral concern? Should we care about their well-being?Two competing ethical theories have addressed suchissues so far. A utilitarian theory which, inBentham's wake, extends moral consideration to everysentient being, and a theory of the rights orinterests of animals which follows Feinberg'sconceptions. This includes various positions rangingfrom the most radical (about animal liberation) tomore moderate ones (concerned with the well-being ofanimals). Notwithstanding their diversity, theseconceptions share some common flaws. First, as anextension of primarily anthropocentric theories (aboututility or rights) they still participate in the flawsof the original setting. Second, extending them tonon-human beings raises the problem of the borderwhich is to be drawn between what can be included inthe purview of moral consideration and what is leftoutside. Third, such theories are not able to distinguishbetween an ethics of wildlife and an ethics ofdomestic life, which too often leads to preposterousstatements. We would like to argue (i) that we should distinguishbetween environmental ethics (concerned withpopulations, species, biotic communities) and animalethics (where animals are taken into consideration individually);(ii) that individualist animal ethics are not relevantfor animal rearing; (iii) that animal rearing is a hierarchicalrelationship which rules are to be found in the fiction of a domesticcontract. Hence, we would like to construct a new conception ofthe ethics of the relation between men and the cattlethey breed based on the idea of a domestic contract.Our main assumption is Mary Midgleys's anthropologicalassumption, according to which human communities,since the Neolithic age, have always included variousanimals, so that relations of sociability have alwaysexisted between human beings and animals within thedomestic community (a mixed community). In order tospecify the hierarchical and non-egalitarian, butinclusive reciprocal obligations and relations insidesuch a community, we will elaborate on the notion ofa ``domestic contract'', an implicitly assumedidea traced back to Lucretius and whichwe will follow up to the physiocrats and Adam Smith.We will show that such an idea relies upon theassumption of communication between cattle farmer andanimals, of shared experience and exchanges betweenthe two parties. We will then show how modern factory,or battery animal farming, can be seen as unilaterallybreaking this domestic contract, forsaking ourduties towards domestic animals.  相似文献   
84.
85.
Introduction: Crashes involving roadway objects and animals can cause severe injuries and property damages and are a major concern for the traveling public, state transportation agencies, and the automotive industry. This project involved an in-depth investigation of such crashes based on the second Strategic Highway Research Program (SHRP 2) Naturalistic Driving Study (NDS) data including detailed information and videos about 2,689 events. Methods: The research team conducted a variety of logistic regression analyses, complemented by Support Vector Machine (SVM) analyses and detailed case studies. Results: The logistic regression results indicated that driver behavior/errors, involvement of secondary tasks, roadway characteristics, lighting condition, and pavement surface condition are among the factors that contributed significantly to the occurrence and/or increased severity outcomes of crashes involving roadway objects and animals. Among these factors, improper turning movements (odds ratio = 88), avoiding animal or other vehicle (odds ratio = 38), and reaching/moving object in vehicle (odds ratio = 29) particularly increased the odds of crash occurrence. Factors such as open country roadways, sign/signal violation, unfamiliar with roadway, fatigue/drowsiness, and speeding significantly increased the severity outcomes when such crashes occurred. The sensitivity analysis of the three SVM classifiers confirmed that driver behavior/errors, critical speed, struck object type, and reaction time were major factors affecting the occurrence and severity outcomes of events involving roadway objects and animals. Practical Applications: The study provides insights on risk factors influencing safety events involving roadway objects, including their occurrence and the severity outcomes. The findings allow researchers and traffic engineers to better understand the causes of such crashes and therefore develop more effective roadway- and vehicle- based countermeasures.  相似文献   
86.
Food has been documented as one of major routes for human exposure to environmental estrogens(EEs), but information on the occurrence of EEs in animal foodstuffs is still scarce.This study analyzed estrogenic activity in 16 types of animal foodstuffs(n = 142) collected from four cities(Wuhan, Guangzhou, Wenzhou and Yantai) of China by combined yeast estrogen screen(YES) bioassay and chemical analysis. By bioassay, all samples' extracts were found to induce estrogenic activities and the bioassay-derived 17β-estradiol equivalent(EEQbio) ranged from 8.29 to 118.32 ng/g. In addition, the samples were analyzed by liquid chromatography coupled to tandem mass spectrometry for further chemical analysis. 17β-Estradiol was found in all samples in this survey at levels of 0.44 to 15.04 ng/g.All samples had 33.1% detection rate of 17α-ethinylestradiol(EE2), and the maximum concentration was 2.80 ng/g. Bisphenol A and 4-nonylphenols were detected in 83.8% and83.1% of samples, with concentrations up to 12.56 ng/g and 35.76 ng/g, respectively.However, the concentrations of estrone, diethylstilbestrol and 4-t-octylphenol were found to be below the limit of detection. A comparison of EEQbiomeasured from the YES assay and EEQchemcalculated from chemical analysis showed good correlation(R2= 0.84). Based on the results, the YES assay can be used as a rapid pre-screening method for monitoring the levels of estrogenic activity in large numbers of animal foodstuffs, and chemical analysis used in combination can be used for the identification of specific EEs.  相似文献   
87.
黄浦江上游汇水区禽畜业污染及其防治对策   总被引:22,自引:0,他引:22  
为定量了解黄浦江上游汇水区禽畜业污染对黄浦江水网地区水环境的影响程度,对汇水区的禽畜业现状进行了调查,提出了各类禽畜的粪尿及其污染物的排泄系统,估算了禽畜粪尿总产生量及流失量。结果表明,汇水区禽畜粪尿流失量达91.3万t/a,由此产生的污染物COD_(Cr)为5.32万t/a,NH_3-N为0.58万t/a,分别是汇水区污染总负荷的38.3%和47.8%,成为黄浦江上游汇水区的主要污染源。对此,提出了防治禽畜业污染的几点对策与建议。  相似文献   
88.
红外分光光度法测定水中油类物质吸附方法的比较   总被引:1,自引:0,他引:1  
吸附处理是红外法测定石油类的一个重要环节.通过实验对吸附柱法和振荡吸附法进行对较,结果表明动植物油质量浓度为0.560 mg/L~145 mg/L的水样,振荡吸附法吸附效率高于吸附柱法.振荡吸附法还具有操作时间短、硅酸镁耗量低、对操作人员危害性小、样品可批量分析的优点.  相似文献   
89.
I am wronged. It is a shameful thing that you should mind these folks that are out of their wits.* *Statement of Martha Carrier (excerpt), hanged as a witch on 19 August, 1692 in Salem, Massachusetts. In all, 20 innocent persons were executed in 1692 as a result of the hysteria attending the Salem witch trials. After the executions, the court was prohibited from "reliance on spectral and intangible evidence". No prosecutions were successful thereafter. See generally, The Salem Witch Trials 1692: A Chronology of Events , at www.salemweb.com/memorial This article provides background information regarding the emerging controversies involving methyl tert -butyl ether (MTBE) and litigation involving leaking underground storage tanks (USTs) in general. It examines (1) the administrative, legislative and litigation history of MTBE in the context of the Clear Air Act and state environmental statues; (2) the importance of applicable RCRA (Resource Conservation and Recovery Act) deadlines regarding UST compliance in these cases; (3) the question of MTBE toxicity for personal injury claims; and (4) the scope of damages available in cases filed by plaintiffs who are not physically impacted by contamination. The authors conclude that the MTBE controversy does not appear to be a legitimate public health or environmental crisis, but rather is yet another speculative product of the American legal industry.  相似文献   
90.
Dune hummocks (small aeolian dunes formed by sand deposition in and around pioneer plants) are the smallest vegetated dune unit; they occur along the entire South African coastline but are poorly studied. Structural properties and distribution of the two main hummock-forming plants:Arctotheca populifolia (a pioneer species with fast growth rate and rapid turnover) andGazania rigens (a later colonizer with slower growth) were investigated. A marked vegetation succession exists across the floor of the slack as a result of the migration of transverse dune ridges across the slack.Arctotheca hummocks were initiated on the newly exposed eastern margin of the slack, and were replaced about midway across the width of the slack byGazania hummocks. Hummocks increased in size with distance from the eastern side of the slack.Gazania hummocks attain a greater vegetation height, support a greater vegetation complexity and mass, and attain a larger maximum size thanArctotheca hummocks. Succession, defined as both the replacement of plant species as well as site modification within the plants over time, was evident. Since the growth form and dynamics determine (1) the ability of plants to trap wind-borne soil and detritus, (2) the shape of the hummocks, and (3) the habitat complexity available to spiders and insects, the ecology of the hummocks is probably determined largely by the vegetation characteristics of the hummock-forming plants.  相似文献   
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