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951.
Alex Loftus 《Geoforum》2009,40(3):326-334
This paper seeks to explore the radical democratic potential in urban artistic interventions. It does so through bringing Gramsci’s concept of nature together with his ‘cultural writings’ and broader debates around avant-garde artistic practice. Empirically, I focus on the work of City Mine(d), a Brussels-based interventionist collective, and Siraj Izhar, a London-based artist-activist. Within Gramsci’s writings, I argue, socio-natural relationships emerge through sensuous activity or work. Making a somewhat more ambitious claim, I suggest that Gramsci’s concept of nature rests on what geographers have come to understand as the production of nature. Whilst attention has only recently turned to this implicit political ecology, much greater attention has been focussed on Gramsci’s cultural insights. For Gramsci, cultural struggles are an integral part of the effort to shape a new reality. Whilst he emphasises the ‘bottom up’ nature of such struggles, the intervention of enlightened outsiders is often a necessary and frustrating complement. However, by turning attention to the manner in which hegemony relates to the production of nature, and through bringing this into dialogue with radical artistic practice, such implicit elitism might be challenged. City Mine(d) and Izhar, I argue, develop a non-vanguardist politics that sees the contestation of hegemony as a struggle integral to the day-to-day nature of cities. 相似文献
952.
Dawn Day Biehler 《Geoforum》2009,40(6):1014-1023
This paper traces changes in the political ecology of insects and chemicals in US public housing since Congress founded public housing in 1937. Drawing upon the literature of critical geographies of home, urban political ecology, and medical history, it argues that the constitution of “public” and “private” space within public housing was deeply entangled with pest control practices there. Prior to 1945, reformers treated the housing as a commons, in part compelled by the mobility of bedbugs and the pesticide used to combat them, both of which were seen as serious health threats. Managers were also motivated by social welfare ideologies, while residents eagerly assisted with communal control policies in order to achieve freedom from the health insults of bedbugs. Following 1945, however, new synthetic pesticides like DDT seemed to stay safely within one apartment unit, encouraging housing managers to abandon community-oriented pest control practices. Meanwhile, curtailed budgets, particularly after the Housing Act of 1949, left the infrastructure of public housing to decay, rendering units more physically permeable even as managers neglected the communities there. The new pesticides nearly eradicated bedbugs, but tenacious populations of German cockroaches blossomed thanks to the permeable buildings and synthetic pesticides. Residents grew increasingly resistant to pesticide use as they observed that cockroach populations went unabated. The paper serves as a case for applying political ecology frameworks to domestic spaces, and also argues that housing quality and domestic pesticide use are not merely private responsibilities but should be regarded as environmental justice issues. 相似文献
953.
Raymond A. Duraiswami Vrishali Dumale Usha Shetty 《Journal of the Geological Society of India》2009,73(5):621-638
Runoff has increased many fold in urban areas due to increase in paved areas, training of streams and construction of storm
water drains. The recharge is therefore continuously decreasing; resulting in depleting groundwater reserves beneath large
cities, especially those situated on water divides. In order to reduce surface runoff and replenish groundwater many advocate
artificial recharge through rainwater harvesting. Conventionally, detailed hydrogeological survey is needed by expert hydrogeologists
to suggest suitable sites for rooftop rainwater harvesting and storage in the subsurface aquifers. Pune, a rapidly growing
city, is under severe stress due to shortage of water in some areas. An effort has been made in this study to identify areas
suitable for rooftop rainwater harvesting by integrating traditional hydrogeological survey data with the help of Remote Sensing
and Geographic Information System. This endeavour has led to develop a program called SLUGGER-DQL which helps to identify
potential sites for rooftop rainwater harvesting and artificial recharge. The program is open ended and several other factors
controlling potential recharge can be easily added on. Based on the results of the present study, potential sites for rainwater
harvesting and artificial recharge have been identified in the Pune University-Shivajinagar-Kothrud area. The present paper
demonstrates the utility of traditional hydrogeological surveys combined with modern techniques in solving problems related
to urban hydrogeology and town planning. 相似文献
954.
CARA ROURE JOHNSON GAIL M. ASHLEY† CAROL B. DE WET‡ RACHEL DVORETSKY‡ LISA PARK§ VICTORIA C. HOVER¶ R. Bernhart Owen SALLY MCBREARTY 《Sedimentology》2009,56(4):1115-1137
Lithological and biological features of a fossiliferous tufa in the Kapthurin Formation, Baringo, Kenya, reveal the presence of a lush wetland in a semi-arid environment during the Middle Pleistocene ( ca 500 ka) in this portion of the East African Rift Valley. Four geological sections, each between 3 m and 8 m in thickness, exposed over a distance of 0·5 km, reveal a 1 to 2 m thick paludal tufa which is composed of three carbonate beds, two dark grey silty claystones and a reddish-brown silty palaeosol. High resolution stratigraphic analysis, carbonate petrography, stable isotope and elemental geochemistry, clay mineralogy and fossil remains (molluscs, ostracods, diatoms and charophytes) reveal a ground water-fed system that fluctuated in depth and periodically disappeared altogether. Oxygen isotope ratios (δ18 O) of tufa matrix range from −4·5‰ to −8·0‰ (Vienna Pee Dee Belemnite) and become more positive up section, indicating the decreasing influence of fault-related fluids and increasing residence time or freshness of wetland water, rather than evaporative enrichment. This spring was situated on a lake margin during low lake levels, thrived during periods of increased ground water input and was ultimately replaced by an alkaline lake. The wetland would appear to have existed during a cool interval within the generally warm Marine Isotope Stage 13 or perhaps during the warm second half of Marine Isotope Stage 13. The ground water source of this wetland arose through a fault system. Thus, the position of the tufa deposit is controlled structurally but the timing and duration of the wetland system may have been influenced by both climatic and tectonic factors. 相似文献
955.
The vertical variation of P forms in sediments of urban shallow lakes in China, Xuanwu Lake, Daming Lake and Mochou Lake,
were sequentially extracted and measured with the method of SEDEX. The results indicated the TP content in the sediment profiles
ranged from 371.94 to 777.25 mg kg−1 for Xuanwu Lake, 1,308.14 to 4,632.63 mg kg−1 for Daming Lake, and 995.49 to 1,860.71 mg kg−1 for Mochou Lake. The results of sequential extraction showed that Ca-P and Fe-P were the main fractions. Meanwhile, the proportions
of Bio-P to TP were 35.24% for Xuanwu Lake, 29.57% Daming lake, and 25.26%, for Mochou Lake, indicating a high potential of
P releasing. The content of Bio-P was significantly and positively correlated with TP (r = 0.978, P < 0.01). Lake hydrations conditions played an important role in the distribution and contents of Bio-P and TP. In the region
with macrophytes, the contents of TP and Bio-P were relatively low. Physicochemical properties of sediments were significantly
related to the fraction distribution and P contents, and might play an important role in controlling P activity and mobility.
Moreover, Fe showed an evident influence on P fraction and the ratio Fe/P might be good indicator to the contents and composition
of active P in sediments. 相似文献
956.
青藏三江源区蒸发量遥感估算及对湖泊湿地的响应 总被引:4,自引:0,他引:4
青藏三江源区湖泊湿地变化一直以来备受关注,气候因素被认为是湖泊湿地变化的主要影响因素.与温度和降水资料相比,气象站获取蒸发量数据比较困难,而遥感技术却为估算区域地表蒸发量提供了一条新的途径.基于地表能量平衡原理,结合MODIS卫星数据和研究区气象资料,建立三江源区蒸发量估算模型,分析研究区内蒸发分布规律,并探讨温度、降水量、风速和蒸发量之间的相关关系,最后分析蒸发量对源区湖泊湿地变化的响应.研究结果表明:三江源蒸发量呈增加趋势,区域蒸发量随水热、植被覆盖和海拔高度差异而变化;研究区蒸发量受温度和降水量影响较大;蒸发量增大是三江源区湖泊萎缩和湿地退化的主要影响因素. 相似文献
957.
958.
基于2000 年、2008 年和2015 年landsat5 TM影像和Landsat8 OLI影像,以单窗算法反演地表温度,研究包头市区近15 a 的城市热岛时空分布及演变特征,并对下垫面土地利用/覆盖类型、 NDVI 与城市热岛的关系进行了定量分析。研究结论表明:包头城市热岛15 a 来呈逐步扩展趋势,且主要集中于裸地区、工矿区、商业和人口密集区三类区域,空间演变趋势与城市扩张格局呈现出高度的一致性;城市热岛效应强度增强,但2008-2015 年以来,市中心区高温区面积比重大大降低;下垫面土地利用/覆盖类型是影响城市热岛空间分布的重要因子,地表温度呈现出裸地>工矿用地>建设用地>城市绿地>农用地>水体的规律;地表温度与 NDVI 呈现显著的负相关关系,即植被指数越高,城市的地表温度越低。 相似文献
959.
Size does matter: City scale and the asymmetries of climate change adaptation in three coastal towns
《Geoforum》2017
Globally, it is smaller urban settlements that are growing most rapidly, are most constrained in terms of adaptive capacity but increasingly looked to for delivering local urban resilience. Data from three smaller coastal cities and their wider regional governance systems in Florida, US; West Sussex, UK and São Paulo, Brazil are used to compare the influence of scale and sector on city adaptive capacity. These tensions are described through the lens of the Adaptive Capacity Index (ACI) approach. The ACI is built from structuration theory and presents an alternative to social-ecological systems framing of analysis on adaptation. Structuration articulates the interaction of agency and structure and the intervening role played by institutions on information flow, in shaping adaptive capacity and outcomes. The ACI approach reveals inequalities in adaptive capacity to be greater across scale than across government, private and civil society sector capacity in each study area. This has implications for adaptation research both by reinforcing the importance of scale and demonstrating the utility of structuration theory as a framework for understanding the social dynamics underpinning adaptive capacity; and policy relevance, in particular considering the redistribution of decision-making power across scale and/or compensatory mechanisms, especially for lower scale actors, who increasingly carry the costs for enacting resilience planning in cities. 相似文献
960.
2000年以来长江流域未见到很典型的梅雨暴雨,尽管如此,所谓"不典型"的区域性致洪暴雨仍时有发生,甚至造成严重洪涝。利用NCEP资料、常规和SCHeREX计划期间的6h一次的高空探测资料和大量的地面自动站资料、多普勒雷达、FY-2C卫星黑体温度资料及NOAA的CMORPH资料,分析了2009年6月29日00:00(协调世界时,下同)至30日00:00引发武汉严重洪涝的强降水。结果表明,尽管中高纬环流和槽脊系统有"错位"现象,但东亚地区鞍形场的存在有利于高原东侧中尺度低压(扰动)的发生发展。随着高原槽东移和西太平洋副热带高压突然西伸,在四川—重庆地区诱生出中尺度涡旋及明显的低空急流,同时上层冷干、下层暖湿空气叠置而形成较强的位势不稳定层结,在低层辐合场的触发下,使致洪暴雨得以发生。该年有较好的水汽输送条件,主要源地在南中国海。因此,即使在大尺度环流不是非常"典型"的情况下,一旦武汉地区存在有利的天气尺度和中尺度系统,且有足够的水汽供应,暴雨仍有可能发生。 相似文献