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1.
Rubber tappers promoted extractive reserves as a sustainable alternative to forest destruction in the Brazilian Amazon. However, the significance of rubber tapping itself has declined since the creation of extractive reserves, which raises questions about the contemporary cultural content of the rubber tapper identity. This paper therefore evaluates rubber tapper identity, using the case of the Chico Mendes Extractive Reserve (CMER) in Acre, Brazil. We first draw on household survey data from the CMER to construct a statistical model of who self-identifies as a rubber tapper. The model shows that socio-economic background, household assets, institutional context, and knowledge of the CMER’s management plan are relevant to understanding rubber tapper self-identification, but not resource management practices, including rubber tapping itself. We therefore pursue qualitative analysis of key informant interviews to better apprehend contemporary understandings of the “rubber tapper” identity, particularly in light of recent shifts in livelihoods from rubber tapping toward cattle ranching. The qualitative analysis shows that there are now several different foundations for self-identifying as a “rubber tapper,” and that there are disagreements concerning the acceptability of cattle ranching among “rubber tappers.” These findings bear implications for research on the relationship of livelihood-based identities with resource management practices and environmental change, as well as public policies that seek to reconcile regional development with forest conservation. 相似文献
2.
Managing the risks of extreme events such as natural disasters to advance climate change adaptation (CCA) has been a global focus. However, a critical challenge in supporting CCA is to improve its linkage with disaster risk reduction (DRR). Based on discussions on similarities and differences between CCA and DRR concerning their spatial–temporal scales, main focuses, preferred research approaches and methodologies, etc., this paper tentatively put forward an analytical framework of “6W” for linking DRR with CCA. This framework presented preliminary answers to a series of fundamental questions, such as “What is adaptation with respect to disaster risk?” “Why adaptation is needed?” “Who adapt to what?” “How to adapt?” “What are the possible principles to assess the adaptation effect?” To bridge the research gaps between CCA and DRR, it is imperative to associate the adaptation actions with both near-term disaster risk and long-term climate change and formulate adaptation strategies at various spatial–temporal scales by embracing uncertainty in a changing climate. 相似文献
3.
There are many examples of “local” discourses aiming to delegitimize environmental issues, demands, actions and governance by arguing that they pursue international goals, defined by international actors that do not meet local needs and frequently oppose them. We focus on the narrative held by large ranchers in the Eastern Amazon, which disqualifies the so-called top-down creation of protected areas that jeopardizes the “local development” these actors have, following the narrative, encouraged and sustained for years. Through the combination of an ontological and constructivist approach of scales, our contribution challenges this scalar construction questioning the “locality” of the large ranchers and showing that their role as “local developers” is actually rooted in regional/national/international scales. We then study the most important effect of the anti-environmental grand scalar narrative: its influence on regional and national decision makers. Well-conceived and publicized scalar scenarios are efficient in this context as in many others. 相似文献
4.
L. Michael Trapasso Ph.D. 《GeoJournal》1994,33(4):449-452
During the Summer of 1992, the author traveled to three distinctive rainforest regions. Two were located in Ecuador: the west coastal rainforest and the northern Oriente, a headwater region of the Amazon Basin. The third rainforest was located in the northwestern region of Belize. As a member of a study group sponsored by Save the Rainforest, Incorporated, the author was involved with the Programme for Belize Research station at Rio Bravo. Having witnessed a variety of types of rainforest destruction in the Brazilian Amazon during the summer of 1989 and the accompaying multitude of indigenous attitudes concerning the same, the author was keenly aware of destruction/preservation activities in these other regions.The indigenous peoples encountered during these travels displayed conservation-minded attitudes and a true desire to save the rainforest. In addition, three ecotourism resorts were encountered during these visits. Though these profit-making establishments do not contribute financial support to local conservation efforts, they do represent large investment concerned with rainforest protection. In Belize the immigration of Mennonites has been considerable. Though their American counterparts may observe a quaint and simplistic lifestyle, in Belize, Mennonites are a major destructive force. 相似文献
5.
Assessment of pressures and impacts on surface water bodies of the Mediterranean. Case study: Pamvotis Lake, Greece 总被引：1，自引：1，他引：0
The aim of the study presented in this article is to assess the ecological status of a surface water body in the Mediterranean using the methodological approach of Driver-Pressure-State-Impact-Response. Based on this approach for the case study analyzed (Pamvotis Lake, Greece), it is concluded that the main drivers, which lead to pressures in the study area are: intensive agricultural activities, alteration of hydrological regime, contamination from point sources and changes in the land-use and fish stocking. The ecological status is assessed by analysing data series of physical, chemical and biological elements that are available from early ’80s. Findings suggest elevated nutrient concentrations sufficient for maintaining eutrophic conditions while their seasonal variability is mostly driven by factors as water level fluctuation, catchment runoff and in-lake biological processes. Subsequently, concerning biotic factors, the poor biodiversity mainly represented by the dominance of the most tolerant species, confirm the previous profile. Since, reference conditions have only recently been established in Greece, the ECOFRAME scheme and the guidelines proposed by the “Intercalibration Group for Mediterranean Lakes” were applied. In terms of the above elements; the water quality status could be characterized as “High”, “High to Good” and “High to Bad”, respectively, whereas the overall ecological status tends to shift in poor conditions. Finally, the major response actions needed should be in the direction of reduced application of fertilizers and chemicals in the cultivated land of the catchment, removal of the point-contamination sources from the catchment, appropriate land-use management and biomanipulation. 相似文献
6.
Assessments of Strength Anisotropy and Deformation Behavior of Banded Amphibolite Rocks 总被引：2，自引：0，他引：2
Esamaldeen Ali Wu Guang Zhao zhiming Jiang Weixue 《Geotechnical and Geological Engineering》2014,32(2):429-438
Assessment of strength anisotropy in transversely isotropic rocks has been one of the most challenging subjects in rock engineering. However, far too little attention has been paid to banded amphibolite rocks. This study aim to evaluate strength and deformation anisotropy behavior of banded amphibolite rocks. The dynamic mechanical tests including ultrasonic pulse test, uniaxial compressive strength, Brazilian test and deformability test were performed on drilled rock samples as a function of foliation plane angle (β = 0°, 30°, 60° and 90°). The results obtained have shown that the dynamic mechanical properties of amphibolite rocks have different values concerning banding plane. Compression and shear waves taken parallel to the foliation plane show highest values than those obtained in the other directions. Under uniaxial test, the banded amphibolite has a U-shaped anisotropy with maximum strength at β = 90° and minimum strength is obtained when β = 30°. Strength anisotropic index ranges between 0.96 and 1.47. It seems that the high range value of anisotropic index is mainly due to slight undulation of foliation planes, that being not perfectly straight. The results of elastic deformation test show that there is no clear dependence on microstructures characteristics of subtype-amphibolite rocks that controlling modulus “shape-anisotropy”. However, in this study, Young modulus values of amphibolite rocks with β follow both types of shape-anisotropy, “U-shape” and “decreased order-shaped”. Thus, this study recommended that further research be undertaken regarding the role of modulus “shape-anisotropy” within the same lithotype. 相似文献
7.
《Geoforum》2015
In the Brazilian Amazon, the long-distance river trading system known as aviamento has linked commodity producers in remote areas to markets in urban centers since the colonial period. Based on a case study from the rural municipality of Lábrea, this article explores continuities and changes in river trading from the point view of riverine residents and river traders. Geographic isolation and seasonal productive needs continued people’s dependence on river traders in 2008–2009, but they had greater choices due to increased access to information, mobility, and alternate markets. Expanded citizenship rights provided access to the vote and to education and other government services, but in a “differentiated” manner that still excluded many rural Amazonians. Given that agroindustry is currently the economic focus for Amazonian development, instead of forest product extraction, these rural producers continued to be forced to rely on informal river traders to meet their needs. 相似文献
8.
George Rapp 《Geoarchaeology》1986,1(4):365-379
Archaeologists frequently ascribe “destruction” layers uncovered during excavation to the effects of earthquake-induced phenomena. Undoubtedly, ancient societies that lived in active seismic zones were as plagued by seismic destruction as we are today. However, other geological phenomena can account for many observed features. This paper reviews the geologic and archaeological background for assessing the evidence for prehistoric earthquake destruction. 相似文献
9.
Carlos Moreira Souza Jr. Kátia Pereira Victor Lins Sanae Haiashy Daniel Souza 《Earth Science Informatics》2009,2(4):205-215
A web GIS (WGIS) system for the Brazilian Amazon, named ImazonGeo and based on open source and public domain data, is presented.
ImazonGeo was built following three principles. First, the system is based on Spatial Data Infrastructure architecture and
web interface built using free software and public domain data. Second, we went beyond visualization of maps and spatial queries
by providing information obtained with spatial analysis models. To do that, we designed a database that stores the results
of previously defined spatial analyses and developed customized reports and query tools to facilitate fast access of information
by end-users. Finally, the system is application-oriented in the areas of forest monitoring, conservation and forest law enforcement,
meaning that it aims to contribute to support the protection of Brazilian Amazon forests. We illustrate these principles by
presenting ImazonGeo’s technology, architecture, content and tools. Moreover, we present two successful cases to demonstrate
how the system is being used. We conclude the paper discussing the challenges and potential solutions to turning our WGIS-SDI
system into an internet hub of geo-information about the Brazilian Amazon. 相似文献
10.
H. Grabert 《Tectonophysics》1983,95(3-4)
In the Amazon region there is a trough-like east-west feature hidden by young sediments. In the trough itself, which is transversely split up, there are Palaeozoic strata which have survived because of the subsidence. This probably took place when the Gondwana continent broke up whereby basaltics intruded. These are attributed to the Jurassic period although they are normally found as sills in the Palaeozoic sediments of the Amazon region.In addition, the Amazon Graben exhibits dislocation by a transcurrent fault system such that the northern block (= Guayana Shield) is transposed considerably to the west when compared with the southern block (Brazilian Shield). The Amazon transcurrent fault is a left-handed shearing system.Relations between the Amazon shearing system and the West African Bénoué Graben, between the sigmoidal bulge of the western South American shore line and the West African continental margin and the proximity of the equator are discussed. 相似文献
11.
J. Stephen Hopkins Paul A. Sandifer M. Richard DeVoe A. Frederick Holland Craig L. Browdy Alvin D. Stokes 《Estuaries and Coasts》1995,18(1):25-42
Shrimp culture technology has resulted in development of a major shrimp farming industry worldwide. Without the shrimp farming industry, increasing demands for shrimp by consumers could not be met, resulting in increased pressure on wild shrimp resources. Unfortunately, there are realized and potential adverse environmental effects on estuarine ecosystems as a result of shrimp farming. The effects can be categorized as wetland destruction for construction of shrimp farms, hypernutrification of estuarine ecosystems by shrim pond effluent, “biological pollution” of native shrimp stocks through escapement of aquaculture stocks, water use and entrainment of estuarine biota, and impacts of shrimp farm chemicals on estuarine systems. While the shrimp farming industry in the United States is small, the United States is effectively addressing all the realized and potential environmental impacts through regulation and research at the federal and state levels. Areas of regulation and research include stringent prohibitions on wetland destruction, regulation of effluents and support of research to eliminate and/or reduce effluents, escapement prevention technology and development of high-health stocks, minimizing entrainment of estuarine biota through water conservation and screening technology, and regulation of chemical use in the shrimp farming industry and support of research on shrimp pathology and environmentally safe disease control. Work is still in progress and not all problems have been resolved to the complete satisfaction of shrimp farmers and estuarine conservationists. However, the situation in the United States should serve as a model of how to encourage sustainable economic development through commercial shrimp farming while abating adverse environmental impacts on estuarine systems. To further improve the situation, the development and adoption of “best management practices” for shrimp aquaculture are recommended. 相似文献
12.
脊槽地貌（Spur and Groove）是现代珊瑚礁礁坪和礁前的典型地貌,其发育特征是揭示珊瑚礁形成与演化过程的重要基础,目前有关环礁各地貌带脊槽地貌形态及成因的研究仍较为薄弱。南海南沙群岛岛礁脊槽地貌发育,是进行相关研究的理想区域。本文以南沙群岛北部道明群礁东北库归沙洲的典型脊槽地貌为研究对象,基于多波束测深数据,借助小波分析和过零点分析等方法,对环礁脊槽地貌形态参数进行定量研究。结果表明：库归沙洲各地貌带脊槽发育平均起始水深为15~16 m,主要为深水脊槽,最大起始水深相差较大（达8 m）,而终止水深相似（平均为16 m左右）。脊槽高差在礁前斜坡和内礁坪为2.15 m左右,在潟湖坡为1.24 m;平均槽宽在礁前斜坡为47.30 m,在潟湖坡达54.92 m。因此,在礁前斜坡脊槽发育相对密集且高差大,潟湖坡脊槽发育相对稀疏且高差小。从礁前斜坡至潟湖坡,脊槽边坡坡度逐渐增大,由“V”型脊槽向“U”型脊槽过渡,槽谷由左倾逐渐转化为右倾。同时,在内礁坪和潟湖坡多发育次一级脊槽,“V”型和“U”型共存。与全球代表性珊瑚礁脊槽形态的对比分析表明：南海地区各环礁多发育深水脊槽,其槽宽和延伸长度的关系部分符合波浪侵蚀作用主控的“V”型脊槽的拟合直线,部分符合生物建造作用主控的“U”型脊槽的拟合直线,表明其可能受上述两个作用共同控制,不同地貌带两者相对强弱不同。同时,频繁的热带风暴的破坏作用可能也是一个要因。 相似文献
13.
《Geoforum》2015
In this article, I ethnographically examine “the biggest experiment in tropical conservation history,” an environmental management approach designed in Brazilian Amazonia. I focus on research conducted by scientists who support this approach using the results of their work at an open-air experiment. Drawing on this ethnographic study I critically revisit Bruno Latour’s deservedly influential ethnography of an open-air laboratory in Brazilian Amazonia. I also engage with his claim that open-air experiments constitute spaces in which scientists can avoid seeing the world as “Nature”—a gigantic collection of inert objects that experts sense they have to bring into order on their own. Latour shows that while working in their Amazonian open-air laboratory scientists perceived the forest as a network comprising human and non-human entities bearing creative capacities. He suggests that such experimentation enables humans to envision environmental management strategies based on human/non-human collaborations. In the open air, experts could thereby transcend the pervasive fatalism that plagues environmental policy circles and rekindle a more optimistic and enthusiastic stance toward environmental management. I argue that Latour’s is a visionary ethnography that anticipates contemporary trends in environmental management approaches. However, I also argue that his celebratory conclusions regarding open-air experimentation are misguided. I show that, while working in the open air, the scientists situated their work within capitalist experiments wherein humans and non-humans creatively collaborate in the construction of new, less inhabitable worlds. 相似文献
14.
《Geoforum》2015
This paper analyses how in the aftermath of one of the worst environmental disasters ever to occur in Spain – the Aznalcóllar Disaster – various environmentalist and conservationist groups mobilised migratory birds to bring new insights and the need for new precautions to the controversy elicited by the spill. The case study, thus, revolves around how environmentalists established a “hybrid collective action” to draw attention to unconsidered risks and impacts of the disaster and thereby make the case for open debate. Building upon this, I engage with two different, though interrelated, theoretical debates that contribute to a rethinking of environmental management (EM) as a social and materially situated practice. Drawing on the idea of “tactic” (De Certeau, 1984), I draw attention to the devices, actions and procedures that environmentalists carried out to resist attempts to minimise the spill and to undermine administrations’ assumptions of control, coherence and singularity associated the idea of management. Drawing on Tim Ingold’s latest work (2007, 2008, 2011), I analyse environmentalists’ most successful tactic: the enactment of migratory birds as “lines”. Together with other authors in this special issue, I will use this notion to make an argument against some of the assumptions of the “hybrid ontology”. In contrast to more essentialists and static notions of non-human agency and politics, the idea of line is particularly useful as a way of understanding how nature(s) can be effectuated differently and how this leads to the imagining of new regimes of cohabitation, human and non-human management and intervention. 相似文献
15.
Prof. Dr.-Ing. Albert Maucher 《International Journal of Earth Sciences》1974,63(1):263-275
Proceeding from the observation that in the Early Paleozoic there is a time-bound, world-wide distributed ore deposit type with scheelite in volcanic-sedimentary series, the question concerning a systematic development of ore deposits connected with an evolution of the earth's crust and mantle is discussed. A schematic model of this development is constructed, which, beginning with a still thin, primeval crust, by way of time-bound stages as for instance greenstone belts and mobile zones, receiving abundant material introduction from juvenile volcanism accompanied with corresponding time-bound ores, leads to the “Assynthic” revolution, giving rise to a crust which is essentially dependent on selfsupport by sedimentary reworking and palingenic magmatism. During the initial “juvenile” period as well as during the palingenic there is significant participation of sedimentary processes, in dependence upon time-bound evolution of the atmosphere and biosphere, for material transport, redeposition and renewed concentration. During the “palingenic” stage the crust is only episodically supplied with mantle material along world-wide volcanic, tectonic lineaments, whereby new ore types, for example the scheelite ores of the Early Paleozoic or the copper-molybdenum ores at the Mesozoic-Cenozoic transition, experience their time-bound formation. 相似文献
16.
An approach for particle breakage simulation based on the framework of discrete element method was proposed in the current study. Convex polyhedron blocks were adopted as elementary particles for the complex particle shapes, and the variability of particle breakage strength is modeled using the invertible function method. Additionally, the traditional modified “Brazilian” criterion was adopted as the breakage criterion. Under the assumption that the eventual fractures within a particle can be determined according to the contact points and the centroid of the particle, once a target particle fulfilled the breakage criterion, it was cut into several fragments by a series of virtual cutting faces, which are consistent with the eventual fractures. With this, the production of local stress and the non-conservation of mass and volume can be avoided. A pre-defined fragmentation mode was also unnecessary for this approach. A series of numerical triaxial tests adopting this new presented approach was then conducted according to the configurations reported in the literature and comparisons made with experimental results. It revealed that while the presented approach is capable of reproducing the macroscopic shear responses and particle breakage characteristics of breakable particle assemblies, some fragmentation modes of particles such as surface grinding and corner abrasion cannot be captured using this approach, presenting an area for future investigation.
相似文献17.
YAO Jianxin BO Jingfang HOU Hongfei WANG Zejiu MA Xiulan LIU Fengshan HU Guangxiao JI Zhansheng WU Guichun WU Zhenjie LI Suping GUO Caiqing LI Ya 《《地质学报》英文版》2016,90(4):1069-1081
Scientific research and productive practice for earth history are inseparable from the accurate stratigraphic framework and time framework. Establishing the globally unified, precise and reliable chronostratigraphic series and geological time series is the major goal of the International Commission on Stratigraphy(ICS). Under the leadership of the ICS, the countries around the world have carried out research on the Global Standard Stratotype-section and Points(GSSPs) for the boundaries of chronostratigraphic systems. In the current International Chronostratigraphic Chart(ICC), 65 GSSPs have been erected in the Phanerozoic Eonothem, and one has yet been erected in the Precambrian Eonothem. Based on the progress of research on stratigraphy especially that from its subcommissions, the ICS is constantly revising the ICC, and will publish a new International Stratigraphic Guide in 2020. After continual efforts and broad international cooperation of Chinese stratigraphers, 10 GSSPs within the Phanerozoic Eonothem have been approved and ratified to erect in China by the ICS and IUGS. To establish the standards for stratigraphic division and correlation of China, with the support from the Ministry of Science and Technology, the National Natural Science Foundation of China and the China Geological Survey, Chinese stratigraphers have carried out research on the establishment of Stages in China. A total of 102 stages have been defined in the "Regional Chronostratigraphic Chart of China(geologic time)", in which 59 stages were studied in depth. In 2014, the "Stratigraphic Chart of China" was compiled, with the essential contents as follows: the correlation between international chronostratigraphy and regional chronostratigraphy of China(geologic time), the distributive status of lithostratigraphy, the characteristics of geological ages, the biostratigraphic sequence, the magnetostratigraphy, the geological events and eustatic sea-level change during every geological stage. The "Stratigraphical Guide of China and its Explanation(2014)" was also published. Chinese stratigraphers have paid much attention to stratigraphic research in south China, northeast China, north China and northwest China and they have made great achievements in special research on stratigraphy, based on the 1:1000000, 1:250000, 1:200000 and 1:50000 regional geological survey projects. Manifold new stratigraphic units were discovered and established by the regional geological surveys, which are helpful to improve the regional chronostratigraphic series of China. On the strength of the investigation in coastal and offshore areas, the status of marine strata in China has been expounded. According to the developing situation of international stratigraphy and the characteristics of Chinese stratigraphic work, the contrast relation between regional stratigraphic units of China and GSSPs will be established in the future, which will improve the application value of GSSPs and the standard of regional stratigraphic division and correlation. In addition, the study of stratigraphy of the Precambrian, terrestrial basins and orogenic belts will be strengthened, the Stratigraphic Chart of China will be improved, the typical stratigraphic sections in China will be protected and the applied study of stratigraphy in the fields of oil and gas, solid minerals, etc. will be promoted. On the ground of these actions, stratigraphic research will continue to play a great role in the social and economic development of China. 相似文献
18.
Mevlut Uyan 《Environmental Earth Sciences》2014,71(4):1629-1639
Landfill site selection is a critical issue in the urban planning process because of its enormous impact on the economy, ecology, and the environmental health of the region. Landfill site selection process aims to locate the areas that will minimize hazards to the environment and public health. Multi-criteria evaluation methods are often used for different site selection studies. The purpose of this study was to determine suitable landfill site selection by using the geographical information system and the analytic hierarchy process in the study area. The final index model was grouped into four categories as “low suitable”, “moderate”, “suitable” and “best suitable” with an equal interval classification method. As a result, 12.69 % of the study area was low suitable, 7.27 % was moderately suitable, 13.79 % was suitable, and 15.52 % was the best suitable for landfilling; 50.72 % of the study area is not suitable for a landfilling. 相似文献
19.
根据造山带地层学地层划分原则,“龙泉关群”可划分为两个性质截然不同的地层单元:其一是“龙泉关构造岩层”,为构造地层单元;其二是“跑泉厂变沉积岩组”,属经典地层单元。前者经历了至少两期变形、变质作用,保留着走向近SN和近EW两组矿物拉伸线理以及角闪岩相和角闪岩相→绿片岩相退变质特征;后者仅发育有一组走向近SN矿物拉伸线理和一期绿片岩相变质作用。这表明:(1)“龙泉关群”实际上包含着两个世代不同的地层单元,应予解体。其中,“龙泉关构造岩层”形成于晚太古代末期,属于“阜平古陆块”刚性基底一部分;“跑泉厂变沉积岩组”的地层层位相当于“五台群”,是“阜平古陆块”西北陆缘带沉积,时代归属早元古代早、中期。(2)“龙泉关群”不是由一个统一的应力场同时形成的一套构造岩,因而不应将其作为一个大型韧性剪切带。(3)“龙泉关群”构成五台碰撞造山带前陆地区的活化基底和活化盖层两个大地构造相。“龙泉关群”的解体及其地层时代的重新厘定支持“板峪口组应归属滹沱群一部分”和“铁堡运动即为五台运动”的看法。 相似文献
20.
Precipitation forecasting using classification and regression trees (CART) model: a comparative study of different approaches 总被引：2，自引：0，他引：2
Bahram Choubin Gholamreza Zehtabian Ali Azareh Elham Rafiei-Sardooi Farzaneh Sajedi-Hosseini Özgür Kişi 《Environmental Earth Sciences》2018,77(8):314
Interest in semiarid climate forecasting has prominently grown due to risks associated with above average levels of precipitation amount. Longer-lead forecasts in semiarid watersheds are difficult to make due to short-term extremes and data scarcity. The current research is a new application of classification and regression trees (CART) model, which is rule-based algorithm, for prediction of the precipitation over a highly complex semiarid climate system using climate signals. We also aimed to compare the accuracy of the CART model with two most commonly applied models including time series modeling (ARIMA), and adaptive neuro-fuzzy inference system (ANFIS) for prediction of the precipitation. Various combinations of large-scale climate signals were considered as inputs. The results indicated that the CART model had a better results (with Nash–Sutcliffe efficiency, NSE?>?0.75) compared to the ANFIS and ARIMA in forecasting precipitation. Also, the results demonstrated that the ANFIS method can predict the precipitation values more accurately than the time series model based on various performance criteria. Further, fall forecasts ranked “very good” for the CART method, while the ANFIS and the time series model approximately indicated “satisfactory” and “unsatisfactory” performances for all stations, respectively. The forecasts from the CART approach can be helpful and critical for decision makers when precipitation forecast heralds a prolonged drought or flash flood. 相似文献