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排序方式: 共有314条查询结果,搜索用时 15 毫秒
91.
Pollutant loads of surface runo inWuhan City Zoo, an urban tourist area   总被引:3,自引:1,他引:2  
The pollutant loads of surface runoff in an urban tourist area have been investigated for two years in the Wuhan City Zoo, China. Eight sampling sites, including two woodlands, three animal yards, two roofs and one road, were selected for sampling and study. The results indicate that pollutants ranked in a predictable order of decreasing load (e.g. animal yard〉roof〉woodland〉road), with animal yards acting as the key pollution source in the zoo. Pollutants were transported mainly by particulate form in runoff. Particulate nitrogen and particulate phosphorous accounted on average for 61%, 78% of total pollutant, respectively, over 13 monitored rainfall events. These results indicate the treatment practices should be implemented to improve particulate nutrient removal. Analysis of the M(V) curve indicate that no first flush effect existed in the surface runoff from pervious areas (e.g. woodland, animal ground yard), whereas a first flush effect was evident in runoff from impervious surfaces (e.g. animal cement yard, roof, road).  相似文献   
92.
贺兰山中段中、上奥陶统米钵山组,在整个区域地层中占有重要地位,它是贺兰山南北向构造形成的重要标志。其地层明显区别于相邻地台区的沉积,对探讨贺兰山早古生代的构造格局及岩相古地理尤为重要。但对米钵山组沉积环境多有争论,观点各不相同。本文对该区米钵山组沉积特征、沉积层序、沉积岩相和古地理环境进行了分析研究,并划分为碎屑流、浊流和正常深水沉积三种类型,推断贺兰山南北向构造在加里东中期开始形成,并延续到白垩纪的新认识。  相似文献   
93.
合流制管网溢流(Combined Sewer Overflows,CSOs)是我国城镇地表水环境日益突出的瞬时污染源,明确其重要污染物溶解性有机质(Dissolved Organic Matter,DOM)的组分和来源对CSOs污染控制具有导向性意义.本研究以北运河上游沙河水库流域为对象,连续采集CSOs过程的样品,通过峰值法、特征参数法和平行因子法等解析CSOs中DOM的三维荧光光谱特征,发现CSOs中DOM主要有类色氨酸(S、T)、类富里酸(A)和类酪氨酸(D),代表内源输入的类色氨酸(S、T)和类酪氨酸(D)占比超过4/5.特征参数法和平行因子法的结果均表明DOM的腐殖化程度较低,生物活性较强,主要为微生物降解生成的和沉积物自身在冲刷和水力输运作用下释放的内源污染,建议CSOs污染控制主要应从内源输入的角度进行,着重控制管道沉积物中污染物的释放.  相似文献   
94.
Solomon Islands is vulnerable to negative impacts from climate change, where people’s livelihoods and their well-being are threatened, especially the viability of isolated communities. Realising the increasing risks from climate change on communities, government, in partnership with aid-donor partners, has invested millions of dollars in climate change projects, through mitigation and adaptation strategies. As a form of adaptation, the government invests in programmes aimed at increasing the adaptive capacity of the vulnerable communities through landscape and seascape projects across the rural communities. Focusing on the “transformation concept” as a long-term adaptation strategy and enlargement of climate engineering and ecological resilience concepts, the paper discusses why building resilience from transformation of rural communities, as well as from landscape and seascape projects, would benefit communities and relevant authorities. This paper describes the findings of a study on two rural villages, Keigold and Mondo, from Ranogha Islands, Western Province, in Solomon Islands, where 80% of households decided to relocate from their old village “Mondo” to their new home “Keigold” after an earthquake in 2007, as part of a self-initiative. The reallocation process can be seen as a case of pro-active community transformation that provides valuable lessons to other rural communities that may be forced to move due to impacts from natural catastrophes, including those explained by climate change risks. Lessons from this experience suggest that policy-makers and non-government organisations should consider and empower local transformation initiatives as a way to building long-term adaptation to climate change.  相似文献   
95.
食品应急储备配置比例及方法研究   总被引:1,自引:0,他引:1       下载免费PDF全文
为提升食品应急储备的科学性、合理性,在总结分析食品应急储备的种类、形式与影响因素的基础上,以我国官方发布的食物与营养发展目标为依据,确定了八大类应急储备食品的基础配置比例,并提出了食品大类配置比例的修正方法,随后综合考虑生产周期、保质期、易储性和储备成本,给出实物储备和产能储备的配置方法,最后提出了单类食品实物储备模式下单品的配置原则和方法,并以单价修正为例对单品选择性修正方法进行了说明,对不断提高突发事件应急保障工作的水平,提升应对突发事件的保障能力,实现受灾群众更科学合理的饮食结构有重要意义。  相似文献   
96.
2005年7-8月国内环境事件数据   总被引:10,自引:8,他引:2  
简要统计了2005年7-8月国内发生的各种环境事件140起,包括沙尘天气1起,污染事件28起,地震7起,虫害3起,旱灾6起,山体滑坡和泥石流25起,以及其他自然灾害90起.最后对统计结果进行了讨论.  相似文献   
97.
为研究沙尘天气大气可吸入颗粒物(PM10)与心血管系统疾病每日门诊人数的联系,采用半参数广义相加泊松回归模型(GAM),在排除了混杂因素如季节趋势、日历效应、气象因素和时间长期趋势等作用的前提下,分析2004年3月1日~5月31日沙尘暴频发区——甘肃省武威市大气PM10与多种心血管疾病每日门诊相对危险度(RR)的关系.结果表明,PM10与男、女总心血管系统疾病门诊RR均在滞后第2d(lag2)的联系有统计学意义.PM10分别在lag3和lag4对男、女性风湿性心脏病门诊RR的影响有统计学意义; PM10(lag2)与男性高血压门诊RR的联系有统计学意义.PM10在lag2对男性缺血性心血管疾病门诊RR的影响有统计学意义;PM10对男、女性心律失常以及充血性心力衰竭门诊RR的影响均无统计学意义.在调整了SO2和/或NO2后,PM10对男、女性心血管系统疾病门诊RR的作用有所下降,但在统计学上仍有意义.然而在分别调整了其他污染物后,SO2和NO2变得无统计学意义.沙尘天气PM10浓度分类模型分析表明,从正常清洁天、轻度污染天到扬沙天气、沙尘暴天气,随着PM10浓度水平的增大,心血管系统疾病(缺血性心血管疾病、充血性心力衰竭、心律失常、高血压、风湿性心脏病)门诊RR也随之增高,呈现一定的剂量效应关系.沙尘天气可吸入颗粒物可引起暴露居民多种心血管系统疾病(缺血性心血管疾病、充血性心力衰竭、心律失常、高血压、风湿性心脏病)门诊人数增多,且均呈现滞后效应. PM10浓度与心血管系统疾病门诊RR表现为一定的剂量效应关系.PM10浓度与沙尘天气强度有密切关系, 随着PM10浓度与沙尘天气强度的增大,暴露居民心血管系统多种疾病日门诊RR也增大,具体为:正常清洁天<轻度污染天<扬沙天<沙尘暴天.  相似文献   
98.
There is an increasing number of “mass events” in mainland China. My study extends the current studies to the context of China and tries to examine the potential impacts of climate changes on human conflicts in China. The results suggest a strong linkage between the deviation of monthly mean temperature from the historical mean and the number of mass events in a province. If the current trend of warming persists, in the next 6–8 decades, the number of mass events in China will increase by over 8.8%.  相似文献   
99.
How do disasters shape local government legitimacy in relation to managing climate‐ and disaster‐related risks? This paper looks at how local authorities in Central Vietnam perceive their social contract for risk reduction, including the partial merging of responsibilities for disaster risk management with new plans for and investments in climate change adaptation and broader socioeconomic development. The findings indicate that extreme floods and storms constitute critical junctures that stimulate genuine institutional change. Local officials are proud of their strengthened role in disaster response and they are eager to boost investment in infrastructure. They have struggled to reinforce their legitimacy among their constituents, but given the shifting roles of the state, private sector, and civil society, and the undiminished emphasis on high‐risk development models, their responsibilities for responding to emerging climate change scenarios are increasingly nebulous. The past basis for legitimacy is no longer valid, but tomorrow's social contract is not yet defined.  相似文献   
100.
The vertical profiles of nonylphenol (NP) and nonylphenol ethoxylates (NPEOs) were investigated in a sediment core from the Beipaiming Channel, North China using high sensitive LC-MS and GC-MS metthods In this core, relatively high concentrations of NP and NPEOs occurred in the surface sediment (≤40 cm), with the maximum value of NP and NPEOs reaching 3539 and 12735 mg/g, respectively, whereas, no NP or NPEOs were detected in deeper sediments (〉40 cm). The high concentrations of NP and NPEOs in the surface layers suggested recent inputs in this area. NPEOs with short ethoxy chains (NPnEO, n=0-3) were dominant in the NPEO mixture with percentages from 54% to 78%, which were similar to the distribution of homolog NPEO in effluents from nearby sewage treatment plants (STPs), indicating that the channel received the effluents from these STPs. The sewage treatment ratio was quite similar to that found in North America before the 1980s. Finally, the concentrations of NP and NPEOs were related to the total organic carbon (TOC) (p〈0.001), suggesting that TOC was an important factor for vertical distribution of NPEOs and NP from the Beipaiming Channel.  相似文献   
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