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Multitemporal landslide inventory analysis of an intertropical mountain in west-central Mexico——Basis for hazard management 被引量:1
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作者 Alejandro Cesar VALDES CARRERA Manuel E.MENDOZA +1 位作者 Teodoro CARLÓN ALLENDE Jose Luis MACIAS 《Journal of Mountain Science》 SCIE CSCD 2022年第6期1650-1669,共20页
Landslides in intertropical mountainous areas of Mexico are a natural hazard that could potentially generate a disaster. Despite this, many areas lack landslide inventories, making it difficult to monitor and efficien... Landslides in intertropical mountainous areas of Mexico are a natural hazard that could potentially generate a disaster. Despite this, many areas lack landslide inventories, making it difficult to monitor and efficiently manage the associated risks for local populations. For this reason, the aim of this research was to undertake a multitemporal landslide inventory and analyze its conditioning factors in the Pico de Tancítaro stratovolcano, which, in recent decades, has presented several high-risk geomorphological events with disastrous consequences for nearby localities. The spatial distribution of landslides and its conditioning factors were mapped at a 1:50,000 scale for the 1995-2020 period, through visual interpretation of orthophotos and satellite images(Landsat, SPOT, and SENTINEL). The conditioning factors that link the most to landslides were Quaternary andesite and basaltic andesite rocks;volcanic cones, mountain river valleys, and very steep to steep slopes(30° to >45°), oriented to the South, North, and East;Andosols and Leptosols;and the oyamel fir and mixed forests. 505 landslide events classified into slides and flows that occurred in 1995, 2004, 2010, and 2015 were identified. New scars generated by the reactivation of landslide processes were also observed. The landslides in the study area were triggered by torrential rains caused by hurricanes and tropical storms;such as hurricanes Alex and Patricia. The inventory and analysis of conditioning factors highlighted the distribution and dynamics of slides and flows in the study area. In addition, the most important factors for studies of landslide susceptibility, hazards, and risks in the Pico de Tancítaro stratovolcano were identified, contributing to the management of geomorphological risks in intertropical mountain areas. 展开更多
关键词 GEOMORPHOLOGY Mass wasting Natural hazards Pico de Tancítaro stratovolcano Risk management
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Mid and late Holocene forest fires and deforestation in the subalpine belt of the Iberian range,northern Spain
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作者 Jose M.GARCIA-RUIZ Yasmina SANJUAN +9 位作者 Graciela GIL-ROMERA Penelope GONZALEZ-SAMPERIZ Santiago BEGUERIA Jose ARNAEZ Paz COBA-PEREZ Amelia GOMEZ-VILLAR Javier ALVAREZ-MARTINEZ Noemi LANA-RENAULT Estela PEREZ-CARDIEL Carlos LOPEZ DE CALLE 《Journal of Mountain Science》 SCIE CSCD 2016年第10期1760-1772,共13页
The conversion of subalpine forests into grasslands for pastoral use is a well-knownphenomenon, although for most mountain areas the timing of deforestation has not been determined. The presence of charcoal fragments ... The conversion of subalpine forests into grasslands for pastoral use is a well-knownphenomenon, although for most mountain areas the timing of deforestation has not been determined. The presence of charcoal fragments in soil profiles affected by shallow landsliding enabled us to date the occurrence of fires and the periods of conversion ofsubalpine forest into grasslands in the Urbión Mountains, Iberian Range, Spain. We found that the treeline in the highest parts of the northwestern massifs of the Iberian Range(the Urbión, Demanda, Neila, and Cebollera massifs) is currently between 1500 and 1600 m a.s.l., probably because of pastoral use of the subalpine belt, whereas in the past it would have reached almost the highest divides(at approximately 2100–2200 m a.s.l.). The radiocarbon dates obtained indicate that the transformation of the subalpine belt occurred during the Late Neolithic, Chalcolithic, Bronze Age, Iron Age, and Middle Ages. Forest clearing was probably moderate during fires prior to the Middle Ages, as the small size of the sheep herds and the local character of the markets only required small clearings, and therefore more limited fires. Thus, it is likely that the forest recovered burnt areas in a few decades; this suggests the management of the forest and grasslands following a slash-andburn system. During the Middle and Modern Ages deforestation and grassland expansion affected most of the subalpine belt and coincided with the increasing prevalence of transhumance, as occurred in other mountains in the Iberian Peninsula(particularly the Pyrenees). Although the occurrence of shallow landslides following deforestation between the Neolithic and the Roman Period cannot be ruled out, the most extensive shallow landsliding processes would have occurred from the Middle Ages until recent times. 展开更多
关键词 福雷斯特开火 HOLOCENE 亚高山带的草地 浅山崩 美化变化 伊比利亚人范围
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Community Monitoring of Forest Carbon Stocks and Safeguards Tracking in Kenya: Design and Implementation Considerations
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作者 Julius G. Muchemi Michael K. McCall +4 位作者 Francis N. Wegulo James M. Kinyanjui Alfred N. Gichu Elias K. Ucakuwun Gilbert M. Nduru 《Open Journal of Forestry》 2015年第4期457-470,共14页
This paper investigates modalities required to design and implement community monitoring of forest carbon stock changes and safeguards implementation in Kenya. General principles and elements were drawn from the UNFCC... This paper investigates modalities required to design and implement community monitoring of forest carbon stock changes and safeguards implementation in Kenya. General principles and elements were drawn from the UNFCCC REDD+ policy frameworks for developing modalities and procedures for designing community forest monitoring system. The paper utilised policy analysis approach used to derive monitoring goals and objectives by assessing the compatibility of Kenya’s policy and legislative framework with monitoring elements provided in the UNFCCC REDD+ policy mechanism. The elements included monitoring goals, objectives, questions, indicators, and methods and tools. Two goals were identified which included, reduction of forest carbon emissions (ER) and monitoring of multiple social and environmental safeguards (SG). Five ER related objectives were identified to include: forest reference emission levels or forest reference levels, drivers of deforestation and forest degradation, Land use activities, eligible ER actions and estimation of forest emissions. Six objectives guiding SG were identified to include: policy, governance, human rights, socio-economic, biodiversity and environmental concerns. Corresponding questions to the goals and objectives were systematically designed. In turns, indicators, depicting quantitative and qualitative measurements, which best provided answers to questions were identified. The various methods and tools used by communities around the world in providing data and information required to satisfy the indictors were identified through literature review. The review identified four methods and tools that included: Remote Sensing and GIS, GPS survey, smartphone survey and Ground trothing. Smartphone and cloud-based server technology were found to be the recent emergent tools in aiding community monitoring of REDD+ projects. The paper argues that local communities and indigenous peoples have the capability and capacity to monitor and undertake forest carbon monitoring and tracking of implementation of safeguards if supported with relevant training;compensated for the time, labour and knowledge they contribute to the process;provided with feedback and involved decision making process. 展开更多
关键词 REDD+ Policy Mechanism COMMUNITY MONITORING FOREST Carbon STOCK SAFEGUARDS Incentivizing COMMUNITIES
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荒漠地下水的大气降水补给及其环境意义——以阿拉善高原晚全新世记录为例 被引量:2
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作者 朱秉启 于静洁 +7 位作者 Patrick Rioual Yan Gao 王平 张一驰 闵雷雷 杜朝阳 王训明 熊黑钢 《第四纪研究》 CAS CSCD 北大核心 2014年第5期994-1012,共19页
在荒漠地区选择何种方法开展地下水的补给及其环境响应研究,是目前干旱区水文学的一个难点和热点问题.本文回顾了前人在相关研究中所选择的包气带示踪方法理论及问题,以我国北方阿拉善高原荒漠为例提取了区域地下水补给和演化的有效信息... 在荒漠地区选择何种方法开展地下水的补给及其环境响应研究,是目前干旱区水文学的一个难点和热点问题.本文回顾了前人在相关研究中所选择的包气带示踪方法理论及问题,以我国北方阿拉善高原荒漠为例提取了区域地下水补给和演化的有效信息,并提供了与之相关的环境变化历史的理解.基于氯质量平衡理论所估算的荒漠非饱和带补给速率与年代学序列等研究表明:阿拉善高原中部巴丹吉林沙漠及周边戈壁等地区在晚全新世距今约700~2000年历史上,经历了数次百年尺度的地下水补给波动过程,并与区域干湿气候波动密切相关;多个剖面记录可以识别出近千年来4个相对湿润(1330~1430年、1500~1620年、1700~1780年和1950~1990年)以及3个相对干旱(1430~1500年、1620~1700年和1900~1950年)的时段.这些记录与青藏高原北缘地区的其他古气候记录具有一致性,并与我国东部气候记录有一定的对应,表明阿拉善高原地下水补给广泛反映了百年尺度上我国西北地区大尺度范围内的气候干湿变化程度,并且可能受到了东亚夏季风强度变化的影响.估算的阿拉善近千年以来的平均补给速率约为1.3 ~ 2.6mm/a,为理解区域地下水补给来源问题带来新的地质证据,但目前的研究结果与其他环境记录有较大出入.需要指出,包气带剖面的环境记录具有很多不确定性,主要来自于氯质量平衡估算中的大气Cl输入量假设和均质土壤包气带剖面(活塞流)的选择.我们认为未来应当通过对比确定性的数据(如区域基准站)和大尺度随机大气Cl输入背景来广泛检验这个不确定性及其误差;并对非饱和带地层的结构均质性、水分平流传输与扩散传输机制的相对重要性以及特征时段的“氯凸剖面”等,提供沉积学、水力学和地球化学等证据的约束. 展开更多
关键词 地下水补给 非饱和带 氯质量平衡理论 古大气降水 晚全新世 阿拉善高原
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