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411.
The main goal of this paper was to explore the relationship between living in industrial areas and individual’s level of psychological health. Using a quasi-experimental design main findings suggest that, regardless of the type of industry that is operating, there was a significant association between living in industrialized areas and decreased levels of well being, optimism and use of active coping strategies. However, results on anxiety and depression were especially high in areas associated with air pollution. Moreover, there was also a significant association between more subjective meanings of place and psychological health. According to a reality-orientation criterion, evidences showed that when individuals live in industrial areas perceptions of their places as industrial are associated with lower depression, anxiety and psychiatric symptoms.  相似文献   
412.
铝对荞麦和金荞麦根际土壤微生物及酶活性的影响   总被引:1,自引:0,他引:1  
以两种耐锅性不同蓼科荞麦属植物荞麦和金荞麦为材料,通过土培盆栽试验,比较研究其根际土壤微生态对铝胁迫反应的差异.结果表明,一定质量分数的Al对荞麦和金荞麦根际土壤绌菌具有显著刺激效应,对金荞麦的影响更大,但Al质量分数过高,对细菌的刺激效应明显减弱,甚至产生抑制作用,荞麦和金荞麦根际土壤真菌数量均随着Al质量分数的升高而明显增加,荞麦根际土壤真菌增加幅度更为显著,Al胁迫下二者根际放线菌数量的变化亦表现出一定的差异;Al胁迫下,养麦和金荞麦根际土壤氨化细菌、硝化绌菌、反硝化细菌等氮素生理群微生物的变化趋势亦显示出明显差异,整体上荞麦根际土壤细菌生珲群对Al胁迫比金荞麦更敏感;Al胁迫对荞麦和金荞麦根际土壤过氧化氢酶活性均表现出较弱的抑制效应,但荞麦根际土壤始终维持较金荞麦更高的过氧化氢酶活性,这与荞麦具有更强的耐铝性有一定的关系,荞麦和金荞麦根际土壤转化酶对Al非常敏感,随着铝的加入,其活性显著下降,荞麦和金荞麦根际土壤脲酶活性的变化趋势基本一致,但整体上荞麦根际土壤脲酶活性均明显低于金荞麦,这是否与其耐铝毒特性的差异有关有待于进一步探讨.  相似文献   
413.
甲磺隆结合残留对土壤酶活性的影响   总被引:3,自引:0,他引:3  
为了研究甲磺隆结合残留对土壤酶活性的影响,将黄粉土(水稻土)经甲磺隆结合残留处理98天,检测土壤脲酶、酸性磷酸酶、过氧化氢酶和蔗糖酶活性.结果表明,甲磺隆结合残留对土壤酶活性的影响不仅与甲磺隆结合残留处理浓度和培养时间有关,同时还与土壤酶种类有关.培养前期(第14天前),甲磺隆结合残留对土壤酸性磷酸酶和过氧化氢酶具有抑制作用,而对土壤脲酶和蔗糖酶的影响则表现为低浓度时激活,高浓度时抑制;培养后期(第14天后),甲磺隆结合残留对土壤脲酶、酸性磷酸酶和过氧化氢酶具有激活作用,在一定浓度范围内(0.050~0.281mg·kg-1)对土壤蔗糖酶也具有一定激活作用;就土壤酶而言,在污染早期,土壤过氧化氢酶对甲磺隆结合残留较敏感,可以作为表征甲磺隆结合残留土壤污染的生物活性指标.  相似文献   
414.
东北地区农业源一次颗粒物排放清单研究   总被引:3,自引:0,他引:3  
采用自下而上的清单编制方法,搜集各农业环节(秸秆燃烧、整地、收割、谷物处理、化肥施用、农机排放、风蚀)排放因子、作物面积和耕作方式等信息,编制了2010年东北地区县级尺度的农业一次颗粒物(PM10和PM2.5)排放清单,并分析了农业源颗粒物排放的时空分布特征.结果表明:1)2010年东北地区农业源一次颗粒物PM10总排放量54.6万t,PM2.5总排放量35.6万t;2)东北地区农业源一次颗粒物PM10排放量最大的农业活动环节是秸秆燃烧,占农业源总排放量的比例为60%,秸秆燃烧排放PM2.5占PM2.5农业源排放量的87%,整地环节是一次颗粒物排放的第2大农业排放源,对农业源排放PM10和PM2.5总量的贡献率分别是27%和6%; 3)PM10和PM2.5的排放强度空间分布表明,东北地区农业源颗粒物排放区域集中在黑龙江省东北部和中部地区,吉林省中部和辽宁省中部地区; 4)PM10和PM2.5排放的时间变化特征显示,PM10农业源排放年变化曲线中,5月份和9、10月份是农业源排放一次颗粒物PM10较多的月份,PM2.5排放集中在9、10月份;5)本研究估算的污染物排放清单的不确定性为184.3%.未来的工作将侧重于典型农业区本土排放因子测定,从而有效减小排放清单的不确定性.  相似文献   
415.
Assessment of the chemical components of Famenin groundwater,western Iran   总被引:2,自引:0,他引:2  
The Faminin area in the semi-arid Hamadan state, western Iran is facing a serious deficiency in groundwater resources due to an increasing demand associated with rapid population growth and agricultural development. The chemical composition of 78 well samples throughout the Faminin area was determined with the aim of evaluating the concentration of the background ions and identifying the major hydrogeochemical processes that control the groundwater chemistry. The similarity between rock and groundwater chemistries in the recharge area indicates a significant rock-water interaction. The hydrochemical types Na–HCO3 and Na–SO4 are the predominate forms in the groundwater, followed by water types Ca–HCO3 and Na–Cl. The high values of electrical conductivity and high concentrations of Na+, Cl, SO42− and NO3 in the groundwater appeared to be caused by the dissolution of mineral phases and would appeared to be caused by anthropogenic activities, such as intense agricultural practices (application of fertilizers, irrigation practice), urban and industrial waste discharge, among others.  相似文献   
416.
人类活动对北江流域径流系列变化的影响初探   总被引:19,自引:4,他引:15  
以北江流域45年(1956-2000年)内降雨量及主要控制性水文站石角站水文资料为基础,研究了流域内降雨径流的变化特征,发现降雨系列基本没有变化,而径流系列呈缓慢上升趋势。对径流系数系列进行分析显示,1973年前后径流系数发生了较大的改变,将1956-1972年做为基准期,利用降雨-径流关系,定量分析了人类活动对径流演变的作用,发现人类活动的间接影响是造成径流增加的原因。最后分析了流域内近20年来的水土流失和植被变化情况,进一步说明了流域内下垫面状况发生了改变。  相似文献   
417.
Brachidontes variabilis is a common fouling mussel species in cooling water systems of tropical coastal power stations. However, there are hardly any data available on the response of B. variabilis to chlorine, a commonly used antifouling biocide. Therefore, lethal and sublethal responses of this mussel to chlorine are of considerable interest to the industry. The response of mussels in terms of mortality pattern (LT50 and LT100) and physiological activities (oxygen consumption, filtration rate, foot activity and byssus thread production) in different size groups (with shell lengths of 7–24 mm) of B. variabilis was studied in the laboratory under different chlorine concentrations (0.25, 0.50, 0.75 and 1.00 mg l?1 for sublethal responses and 1, 2, 3 and 5 mg l?1 for mortality). The results showed that the exposure time for 100% mortality of mussels decreased significantly with increasing chlorine concentration. However, mussel size was not a determinant of its chlorine tolerance: all size groups tested (with shell lengths of 7–24 mm) took comparable exposure times to reach 100% mortality at a given chlorine concentration (1–5 mg l?1). All size groups of B. variabilis showed a progressive reduction in physiological activities such as oxygen consumption, filtration rate, foot activity and byssus thread production, when chlorine residuals were increased from 0 to 1 mg l?1. The data generated in the present work are compared with similar data available for other tropical fouling mussel species to see how far relative chlorine toxicity could have influenced the relative distribution of the mussels inside the seawater intake tunnel of a power station at Kalpakkam in India. It is shown that in this insufficiently chlorinated system, the relative distribution of Brachidontes striatulus, B. variabilis and Modiolus philippinarum reflects the relative tolerance of the species to chlorine.  相似文献   
418.
Industrial growth is being attributed with adverse environmental effects and has necessitated stricter environmental management policies. Formulating such policies is limited by the difficulty in understanding the trends of monitoring data. This study is aimed at the application of fuzzy comprehensive assessment (FCA) to integrate environmental contaminants in Agbara industrial estate, Nigeria, to measure the extent of impact of industrial activities on the host community. Samples of water, plants (Pteridium aquilinum, Sacciolepis africana, and Panicum maximum), soil, and sediments were collected within the estate. Water samples were analyzed for quality parameters using standard methods. Metals (Co, Cr, Cd, Cu, and Mn) were investigated in all the samples using an atomic absorption spectrophotometer. The data were modeled with FCA. The results showed Cr as the major contaminant (34–252?µgL?1). High phosphate contributed to large plant growth in the area. FCA results showed that water samples were in the pristine classification; sediment samples were extremely impacted. The vegetation growth and the sediment precipitation were responsible for the cleaning-up of the pollutants discharged downstream. The FCA of the plants indicated high metal bioaccumulation and not only showed the plants’ phyto-remediation potential but also that the metals may pose threats to human health through the food web. The activities in the estate are contributing contaminants to the environment with potential negative effects.  相似文献   
419.
Human activities and oceanic influences like mixing and/or upwelling define the hydrochemical and biological characteristics of coastal regions. In Sanya Bay, northern South China Sea, the balance between these two influences on spatial and temporal scales is poorly understood. The influence from human activities was due to discharge from Sanya River, whereas the most important marine influence was related to seasonal changes in hydrodynamics. Spatial differences (p<0.05) in total nitrogen (TN) and chlorophyll-a (Chl-a) were observed. Seasonal differences were observed for temperature and nutrients. Human activities are the dominant factor influemcing hydrochemistry in the inner bay. This region exhibited the maximum influence of discharge from Saya River as estimated by higher nutrient levels. Oceanic influences like upwelling and mixing caused by monsoons are the dominant factors influencing hydrochemistry in the central and outer bay. Both human activities and oceanic influences play important roles in coastal ecosystems in Sanya Bay. This study has defined these characteristics so that better management policies can be enacted.  相似文献   
420.
基于SWAT-WEAP联合模型的西辽河支流水资源脆弱性研究   总被引:2,自引:0,他引:2  
气候变化与人类活动对水循环及水资源安全的影响是近代水科学面临的主要科学问题。以西辽河支流老哈河流域为研究区,探索了一种水文模型耦合方法(SWAT-WEAP),以水短缺量为指标,同等考虑水资源供给端与需求端,对气候变化与不同人类利用情景下水资源系统脆弱性进行定量分析,结果表明:①暖干化气候情景比暖湿化气候情景明显加剧了老哈河流域水资源系统的脆弱性,降水减少10%导致的水短缺量比降水导致10%所缓解的短缺量要多31.17%;②气候变化对流域农业灌溉用水影响最大,对城乡生活用水和工业用水影响相对很小;③老哈河流域水资源系统脆弱性的主要驱动力之一源自农业不合理灌溉,发展畜牧业、 改变种植结构与高效节水灌溉是缓解水短缺、 降低水资源系统脆弱性最为有效的措施,也是应对气候变化最为有效的方式;④基于供水端的措施(如水库)在暖干化气候时由于水资源供给来源受限,其缓解作用有所减弱。  相似文献   
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