Geological heritage inventory procedures and templates have been principally emerged from European countries. Each of these countries has developed its proper method of inventory based on its natural heritage, recogni...Geological heritage inventory procedures and templates have been principally emerged from European countries. Each of these countries has developed its proper method of inventory based on its natural heritage, recognized on local and/or regional scales. Natural sites were mainly identified and characterized in a particular geological context, which is usually very unique, valuable and impressive;resulting in the protection of the sites. Madagascar is known internationally as a beautifully landscaped island, but the impressive sites were not cataloged. We carried out a series of field inventory of potential geological sites within the Isalo National Park in southern Madagascar. We invented several inventory sheets in order to record the most detailed information about the sites identified within the park. This is to aid in organizing the park and to establish a sustainable base for the creation of a geopark, and also they help us to build a database for geosites and their classifications. This article suggests a prototype model for inventorying intangible geosites, paleosites and geomorphosites. Our inventory sheets help to identify and to promote geological importance of any sites, not only for academia but also for other sectors such as tourism and conservation.展开更多
Although Madagascar has long been recognized as a biodiversity hotspot for conservation, very little is yet known about its diverse endemic fossils and the original beauty of its geotopes. The richness and endemicity ...Although Madagascar has long been recognized as a biodiversity hotspot for conservation, very little is yet known about its diverse endemic fossils and the original beauty of its geotopes. The richness and endemicity of geodiversity constitute nonrenewable natural resources, which deserve to be valorized and protected. Protection of natural heritage resources, aligned with geotourism, can provide a sustainable way for the population to rise out of poverty. The main purpose of this work is the instauration of Geopark, a long-term project in Madagascar National Parks to support geotourism and sustainable development. Given its outstanding landscape and its unique bio- and geo-diversity, we adopt Isalo Park as a pilot site, and suggest that this specific area is suitable for a Geopark. Following our field investigation, inventory and geodiversity assessments within the park are now underway, which will contribute to the implementation of Isalo Geopark.展开更多
The causes and consequences of soil erosion in Madagascar have been the focus of recent environmental debates. The Betsiboka, Madagascar＇s largest river stretching 600 km from the high central plateau to the northwes...The causes and consequences of soil erosion in Madagascar have been the focus of recent environmental debates. The Betsiboka, Madagascar＇s largest river stretching 600 km from the high central plateau to the northwest coast on the Mozambique Channel, is a major conduit for transporting lateritic soils and sediments derived from the highlands of Central Madagascar to the sea. These en- trained lateritic sediments color the river a blood-red hue, as if the life of the island is being drained away. In this study, Landsat visible and near infrared spectral bands are used to map the underwater sediments especially under the sea and in the interface between seawater and freshwater. Band color composites, single bands and band ratios are used to improve the detection of underwater sediments including sand bars and delta lobes. We show the evolution of the bay, coastline, delta, and change detection results derived from Landsat satellite images recorded in 1973, 1989, 1999, 2000 and 2003, respectively. Results indicate that sedimentary transport and suspension in Bombetoka Bay has significantly changed during the past 30 years, with a dramatic increase in the amount of sediment moved by the river, and deposited in the estuary and in offshore delta lobes. These changes have adversely affected agriculture, fisheries, and transportation for one of Madagascar＇s largest ports. The changes are attributed to increased erosion following large-scale deforestation, bush fires, and overgrazing in the river basin.展开更多
文摘Geological heritage inventory procedures and templates have been principally emerged from European countries. Each of these countries has developed its proper method of inventory based on its natural heritage, recognized on local and/or regional scales. Natural sites were mainly identified and characterized in a particular geological context, which is usually very unique, valuable and impressive;resulting in the protection of the sites. Madagascar is known internationally as a beautifully landscaped island, but the impressive sites were not cataloged. We carried out a series of field inventory of potential geological sites within the Isalo National Park in southern Madagascar. We invented several inventory sheets in order to record the most detailed information about the sites identified within the park. This is to aid in organizing the park and to establish a sustainable base for the creation of a geopark, and also they help us to build a database for geosites and their classifications. This article suggests a prototype model for inventorying intangible geosites, paleosites and geomorphosites. Our inventory sheets help to identify and to promote geological importance of any sites, not only for academia but also for other sectors such as tourism and conservation.
文摘Although Madagascar has long been recognized as a biodiversity hotspot for conservation, very little is yet known about its diverse endemic fossils and the original beauty of its geotopes. The richness and endemicity of geodiversity constitute nonrenewable natural resources, which deserve to be valorized and protected. Protection of natural heritage resources, aligned with geotourism, can provide a sustainable way for the population to rise out of poverty. The main purpose of this work is the instauration of Geopark, a long-term project in Madagascar National Parks to support geotourism and sustainable development. Given its outstanding landscape and its unique bio- and geo-diversity, we adopt Isalo Park as a pilot site, and suggest that this specific area is suitable for a Geopark. Following our field investigation, inventory and geodiversity assessments within the park are now underway, which will contribute to the implementation of Isalo Geopark.
基金supported by the National Natural Science Foundation of China (Nos.EAR 02-21567,EAR 02-07997,40821061)the Fund from Ministry of Education of China (No.B07039)
文摘The causes and consequences of soil erosion in Madagascar have been the focus of recent environmental debates. The Betsiboka, Madagascar＇s largest river stretching 600 km from the high central plateau to the northwest coast on the Mozambique Channel, is a major conduit for transporting lateritic soils and sediments derived from the highlands of Central Madagascar to the sea. These en- trained lateritic sediments color the river a blood-red hue, as if the life of the island is being drained away. In this study, Landsat visible and near infrared spectral bands are used to map the underwater sediments especially under the sea and in the interface between seawater and freshwater. Band color composites, single bands and band ratios are used to improve the detection of underwater sediments including sand bars and delta lobes. We show the evolution of the bay, coastline, delta, and change detection results derived from Landsat satellite images recorded in 1973, 1989, 1999, 2000 and 2003, respectively. Results indicate that sedimentary transport and suspension in Bombetoka Bay has significantly changed during the past 30 years, with a dramatic increase in the amount of sediment moved by the river, and deposited in the estuary and in offshore delta lobes. These changes have adversely affected agriculture, fisheries, and transportation for one of Madagascar＇s largest ports. The changes are attributed to increased erosion following large-scale deforestation, bush fires, and overgrazing in the river basin.
