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11.
Woodcutting and territorial claims in Mali 总被引：2，自引：0，他引：2
In Mali, amidst moves toward political decentralization and the transfer of authority to manage natural resources, woodcutting has become an important tool for the assertion of territorial claims by villagers. The decentralization process has itself led to a profound political shake-up between the central state seeking to maintain land ownership and the de facto management of land by customary village authorities. But it is, however, primarily the devolution of forest resource management to village-led organizations that has prompted the cross-scale legitimization and assertion of various territorial claims from 1995 onwards. Based on two in-depth case studies on the outskirts of Bamako, Mali, the authors illustrate how new practices revolving around woodcutting and charcoal-making have been instrumental in intra- and inter-village disputes. At the village level, this transfer tends to exacerbate tenure claims over land and trees with the reactivation of autochthony-related arguments and thus the risk of excluding the most vulnerable social groups which are typically involved in woodcutting. At the inter-village level, this gives villages the opportunity to claim and demarcate boundaries by cutting, painting signs on some trees, or more radically tree felling being carried out solely to demonstrate appropriation. At the municipal level, this transfer leads to political and social adjustments between customary and decentralized authorities, each struggling to build their legitimacy in natural resource management. 相似文献
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Crop area mapping in West Africa using landscape stratification of MODIS time series and comparison with existing global land products 总被引：6，自引：0，他引：6
Elodie Vintrou Annie DesbrosseAgnès Bégué Sibiry TraoréChristian Baron Danny Lo Seen 《International Journal of Applied Earth Observation and Geoinformation》2012,14(1):83-93
In Africa, food security early warning systems use satellite-derived data concerning crop conditions and agricultural production. Such systems can be improved if they are provided with a more reliable estimation of the cultivated area at national scale. This paper evaluates the potential of using time series from the MODerate resolution Imaging Spectroradiometer MOD13Q1 (16-day composite of normalized difference vegetation index at 250 m resolution) to extract cultivated areas in the fragmented rural landscapes of Mali. To this end, we first stratified Southern Mali into 13 rural landscapes based on the spatio-temporal variability of NDVI and textural indices, using an object-oriented classification scheme.The accuracy of the resulting map (MODIScrop) and how it compares with existing coarse-resolution global land products (GLC2000 Africa, GLOBCOVER, MODIS V05 and ECOCLIMAP-II), was then assessed against six crop/non-crop maps derived from SPOT 2.5 m resolution images used as references. For crop areal coverage, the MODIScrop cultivated map was successful in assessing the overall cultivated area at five out of the six validation sites (less than 6% of the absolute difference), while in terms of crop spatial distribution, the producer accuracy was between 33.1% and 80.8%. This accuracy was linearly correlated with the mean patch size index calculated on the SPOT crop maps (r2 = 0.8). Using the Pareto boundary as an accuracy assessment method at the study sites, we showed that (i) 20-40% of the classification crop error was due to the spatial resolution of the MODIS sensor (250 m), and that (ii) compared to MODIS V05, which otherwise performed better than the other existing products, MODIScrop generally minimized omission-commission errors. A spatial validation of the different products was carried out using SPOT image classifications as reference. In the corresponding error matrices, the fraction of correctly classified pixels for our product was 70%, compared to 58% for MODIS V05, while it ranged between 40% and 51% for the GLC2000, the ECOCLIMAP-II and the GLOBCOVER. 相似文献
13.
Good, bad or 'necessary evil'? Reinterpreting the colonial burning experiments in the savanna landscapes of West Africa 总被引：2，自引：0，他引：2
A simple ecological model underlies contemporary fire policy in many West African countries. The model holds that the timing (or seasonality) of annual savanna fires is a principal determinant of vegetation cover. The model's origin can be traced to the ideas held by influential colonial scientists who viewed anthropogenic fire as a prime force of regional environmental degradation. The main evidence in support of the model derives from the results of a series of long-term burning experiments carried out during last century. The experimental results have been repeatedly mapped onto fire policy often taking the form of a three-tiered model in which fire exclusion is considered the ultimate management objective, late dry-season fire is discouraged and early dry-season fire is allowed but only under specific, often state-controlled circumstances. This paper provides a critique of contemporary fire policy in the region and the fire ecology model on which it is based. Through an analysis of burn scars for the 2002–3 fire season generated from ETM+ imagery, the study documents the spatiotemporal pattern of burning for an area in southern Mali. It argues that current policy, which is informed by an a-spatial model, cannot adequately account for the critical pattern of burning that is characteristic of the region. A reinterpretation of the burning experiments is presented in light of four factors: empirical data; recent developments in patch-mosaic theory; historical evidence on the effects of fire suppression; and data on indigenous burning strategies, all of which suggest a need to reconsider current fire policy. 相似文献
14.
SahelbioclimaticzonecrossNorthAfricabe-tweenl7oNandl3"Nborders,theSaharaDeserttothenorthandtheSudansavannatothesouth,beinganimportantfragileecologicalzoneintheworld.SincethesevereSudano-Saheliandroughtof1968-l973sandydesertificationhasresultedinaverymiserableconse-quencestolocalpeople,asaSahelcountryinwestAhica,theRepublicofMaliisoneofthecountriesmostseverelyaffectedbydroughtanddesertification,AccordingtotheinvestigationsoftheexpertgroupoftheLanzhouInstituteofDesertResearch,theChineseA-… 相似文献
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Since the late 1950s, production of both cash-crop cotton and food crops has increased immensely in the Malian cotton zone. The response of farmers to external incentives or obstacles has been swift. In an opportunistic way, farmers seem to seek immediate and maximum profits. This has been particularly evident with the boom in both cotton and food crop production after the devaluation of the CFA franc in January 1994. Such reactions support the idea that it is not only African pastoral production systems which are non-equilibrial and opportunistic, but that this also characterises farming communities. Furthermore, the agricultural development in the cotton zone is regularly said to cause serious environmental degradation mainly through deforestation and soil depletion. The paper questions this view. The environmental transformation taking place is analysed, but whether this transformation represents ‘degradation’ or ‘improvement’ is largely a normative question subject to the values and environmental perceptions of the individual actors. 相似文献
17.
Symbols, not data: rare trees and vegetation history in Mali 总被引：1，自引：0，他引：1
Chris S Duvall 《The Geographical journal》2003,169(4):295-312
Historical analysis of botanical literature concerning the trees Gilletiodendron glandulosum and Guibourtia copallifera in Mali's Manding Plateau reveals that the dominant representation of these plants has helped to perpetuate colonial-era theories of vegetation history, African land management, and natural resource politics in West Africa. The French botanist Aubréville described these plants as proof of the theory of vegetation history that blamed poor land management by rural Africans for a steady and continuing destruction of vegetation from its presumed original forest climax. Although Aubréville's representation of these trees was justified within the 1930s scientific context he worked, subsequent researchers uncritically maintained his conclusions even though the changed scientific context in which they worked did not justify such representation. Subsequent ecological research also failed to substantiate Aubréville's representation of these trees, yet several influential modern botanical works have uncritically accepted colonial-era botanical literature founded on his ideas. Thus, modern botanical works have perpetuated a simplistic and inaccurate narrative of resource use under an appearance of objectivity. As a result, policy recommendations based on the modern botanical sources remain almost identical to colonial-era policies. Based on the similarity of colonial-era and modern portrayals of these trees, this paper argues that a regional discursive formation recently described by other authors may be expanded to include southern Mali, which carries negative implications for decentralization reform in Mali. 相似文献
18.
藏北比如中侏罗世马里组遗迹化石的发现及其意义 总被引：1，自引：0，他引：1
描述了藏北比如地区中侏罗统马里组的遗迹化石8属8种（其中包括1个新遗迹属和2个新遗迹种）：表面光滑无饰、具有较薄管壁和密集新月形回填构造的不分枝水平潜穴Beaconites biruensis ichnosp.nov.,沿层面分布的哑铃形潜穴Bifungites cf. hanyangesis Yang,圆柱状厚管壁的分枝并构成假网状的潜穴Biruichnus maliensis ichnogen. et ichnosp. nov.,窄长的、内肢抓痕的二叶形遗迹Cruziana ichnosp.,以垂直于层面的圆管为中央放射出排列不规则且粗细变化较大细管的多分枝潜穴系统Micatuba cf. verso Chamberlain,平行或微斜交于层面的圆柱状微弯曲或弯曲的潜穴Palaeophycus ichnosp.,栖管段有规律地交替向两侧分叉呈Z字形或锯形的三维潜穴系统Treptichnus cf. bifurcus Miller,平行层面的、具有蹼状构造的简单U形潜穴Rhizocorallium ichnosp.。西藏比如地区中侏罗统马里组有大量的波状层理、透镜状层理和脉状层理等潮汐层理,发育侵蚀构造,上部紫红色含砾粗砂岩、长石砂岩发育,为滨岸相沉积。马里组的遗迹化石以浅层内生迹的爬行觅食潜穴和居住滤食性潜穴占有优势,也见有节肢动物的爬行迹和系统觅食潜穴,且产遗迹化石的层位见小型干涉波痕,为近海浅水中至低能的沉积环境。 相似文献
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This study aims to explain a farmer–herder conflict in the inland Niger delta of Mali. We focus on the interests and motivations of the actors involved in the conflict and the rent seeking of the local administration in handling the conflict. Since independence, the customary pastoral leaders (the jowros ) have gradually lost power and wealth to the benefit of previously underprivileged farmers (the rimaybé ). We argue that this process is mainly the result of national policies and laws giving priority to agricultural development at the expense of pastoralism. The result has been large-scale conversions of dry season pastures to rice fields. This pastoral marginalisation also results in increased land use conflicts between herders and farmers. In addition, rent seeking by local officials is perpetuating land use conflicts in the area. Hence, officials are benefiting from conflicts, while especially pastoralists, but also farmers, are losing out. The droughts of the 1970s and 1980s, leading to a more rapid encroachment of rice fields on pastures, as well as the power vacuum that emerged in the early days of the decentralisation process, further aggravated land disputes. Finally, we use this case study to call for an inclusion of issues of rent seeking and corruption more centrally in political ecology. 相似文献
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马里地处西非克拉通腹地,境内大量出露前寒武纪结晶基底,发育大规模的比里姆（Birimian）绿岩带。带内受到后期不连续造山事件的改造,内生金属矿产资源禀赋极好,是西非地区重要的产金岩系。国内关于马里矿产地质特征和矿业开发前景的相关研究较少。为了补充该研究领域,本文系统总结了马里的矿产资源禀赋和开发现状,对其矿业投资环境进行了重点分析研究。研究结果表明,马里区域位置和成矿地质条件优越。目前马里已探明的固体矿产资源种类10余种,其中金矿资源储量2898 t,居非洲地区前列。此外还拥有丰富的锂矿、铀矿、磷酸盐矿、铁矿等矿产资源,多数未进行系统勘查,资源潜力极大。马里的矿产资源除金矿外,其他矿产资源开发程度较低。马里的矿业投资活动活跃,主要投资矿种为金矿、锂矿、铀矿等。马里矿业投资环境整体上较好,矿业相关法律健全,政策支持力度较大,鼓励外资进入矿业领域。中资矿业企业可以重点关注马里的金、锂、铀等优势矿种,选择合适时机开展相关勘查投入,以适合自身的模式进行矿业开发合作。 相似文献