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961.
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土地征收工作对保障建设、保护耕地、保障被征地农民的利益具有重要作用。随着经济社会发展,土地征收的制度设计出现了一些问题,该文通过探讨分析土地征收在制度层面的缺陷,提出了征地制度改革的一些对策建议。 相似文献
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Don Aldiss Helen Burke Barrie Chacksfield Richard Bingley Norman Teferle Simon Williams David Blackman Richard Burren Nigel Press 《Proceedings of the Geologists' Association. Geologists' Association》2014
Long term planning for flood risk management in coastal areas requires timely and reliable information on changes in land and sea levels. A high resolution map of current changes in land levels in the London and Thames estuary area has been generated by satellite-based persistent scatterer interferometry (PSI), aligned to absolute gravity (AG) and global positioning system (GPS) measurements. This map has been qualitatively validated by geological interpretation, which demonstrates a variety of controlling influences on the rates of land level change, ranging from near-surface to deep-seated mechanisms and from less than a decade to more than 100,000 years’ duration. 相似文献
966.
《Geoforum》2014
In Ghana, the contested concepts of “land grabbing” and “land transaction” are strategically applied by proponents of critical and win–win discourses respectively to describe outcomes of land deals. Using case study methods and discourse analysis, this paper explores four cases of biofuels investments in Ghana and the implications of the choice of concepts used to represent them. Proponents of the critical discourse use the “land grabbing” concept to invoke imageries of “illegality”, “theft” and “food insecurity” when describing land deals. Consequently, some biofuels investments have been hampered in their potential to generate profit and local employment. The biofuel investors in this study, whose projects have been labeled “land grabbing”, therefore switched to food production to downplay public scepticism. Proponents of the win–win discourse portray biofuels investments as “pro-poor” projects and use the “land transaction” concept to pre-empt possible public criticisms in the media and elsewhere. Such representations of these biofuels investments are therefore mainly intended to pre-empt criticisms or attract public praise. Some projects with potentially promising outcomes have thus been terminated, while others with problematic outcomes have continued to be promoted. In contexts characterized by weak land regulations and ambivalence towards large-scale agriculture, the trajectory and outcomes of biofuels investments are often influenced by land deal representations drawn from global discourses and how they interact with pre-existing local discourses. 相似文献
967.
《Geoforum》2014
Land degradation has been a major political issue in Java for decades. Its causes have generally been framed by narratives focussing on farmers’ unsustainable cultivation practices. This paper causally links land degradation with struggles over natural resources in Central Java. It presents a case study that was part of a research project combining remote sensing and political ecology to explore land use/cover change and its drivers in the catchment of the Segara Anakan lagoon. Historically rooted land conflicts have turned the land into a political battlefield, with soil erosion being the direct outcome of the political struggles. Starting from an analysis of environmental changes using satellite images and historical maps, the research explored a history of violent displacements in the frame of a series of brutal insurgencies and counterinsurgencies in the 1950/60s. In these struggles over national political power, entire villages were erased, and peasants’ land was appropriated by the state. This political history is ‘inscribed’ in today’s landscape. The contested land comprises some of the most erosion-prone sites in the entire catchment of the lagoon. The landscape of erosion is a landscape of conflict and a symbol of historical violence and injustice. In line with our research in other parts of the catchment, the case study presented here challenges dominant political discourses about the nature of upland degradation in Java. It provides insight into still unresolved and underexplored chapters of Indonesian history and presents a strong plea for combining land use change science and (historical) political ecology. 相似文献
968.
内蒙古东部科尔沁右翼中旗地区孟恩陶勒盖岩体由二长花岗岩、 花岗闪长岩、 英云闪长岩组成,属于高钾钙碱性岩系。岩石具有SiO2较高(平均为72.03%),富碱并相对富K2O(K2O/Na2O平均为1.08),Mg#较低(平均为0.30),铝饱和指数(A/CNK)较高(平均为1.08)的特点。在ACF图解中,岩石投影在S型花岗岩中,标准矿物中普遍出现刚玉分子,岩石中可见白云母,个别可见石榴石,应属S型花岗岩范畴。岩石稀土总量较低(∑ REE平均为120.76×10-6),轻、 重稀土分馏明显((La/Yb)N=3.2~32.5),有变化较大的负铕异常(0.2~0.8);在微量元素蜘蛛网图上,强烈富集大离子亲石元素(如Rb、 Ba),高场强元素(如Ti)强烈亏损,在微量元素与上陆壳标准化及(La/Yb)N-δEu图解中,物源属于壳源。岩体Sr的含量平均为176.57×10-6,小于300×10-6,Yb含量平均为1.3×10-6,小于2×10-6,属于喜马拉雅型花岗岩,源岩可能为含石榴石和斜长石的高压麻粒岩相,形成于加厚地壳部分熔融的结果,其形成的压力可能为0.8~1.5 GPa。在R1-R2图解、 Yb-Ta图解中,岩石均投影在同碰撞环境。因此,该岩体是中三叠世挤压背景下同碰撞壳源S型花岗岩,为华北板块与西伯利亚板块碰撞上限的约束提供了资料。 相似文献
969.
“山水林田湖草沙生命共同体”理念为沙地生态环境治理指明了新方向,但是在沙区开展什么研究却是新课题。本文基于生态建设面临的挑战,从山水林田湖草沙一体化治理的角度,探析了科尔沁沙地生态治理的研究方向及应重点关注的问题。 相似文献
970.
风是干旱、半干旱区风蚀风积地貌发育的动力基础,我们通常使用风速资料探讨区域风况,但选取不同的风速资料研究同一区域风况时结果存在差异。以毛乌素沙地为例,分别选取中国气象数据网(CMDC)的日最大风速及风向与美国国家气候数据中心(NCDC)的日8个定时观测风速及风向,对比分析起沙风特征。结果表明:(1)毛乌素沙地平均起沙风速相差较小,但起沙风频率明显在CMDC数据源中较高;(2)毛乌素沙地年起沙风向均以WNW、W和NW为主,但年起沙风次风向、不同区域夏季和秋季起沙风次风向组成均在CMDC数据源中较复杂,且起沙风主次风向频率均在CMDC数据源中较高;(3)毛乌素沙地整体均属于低风能环境,中等风向变率,锐双峰或宽单峰风况,但以最大风速计算的年输沙势约是以定时观测风速计算结果的3.3倍。基于两套数据源定量对比分析毛乌素沙地风况及输沙势,这对区域风况研究是一种新的尝试,以期提高对不同数据源提供的风速差异的认识,为今后不同区域的起沙风分析提供一定的参考。 相似文献