scholarly journals Impacts of Wood Fuel Uses on Forest Cover: The Case of Semiarid Areas in Northern Tanzania

2021 ◽  
Vol 47 (4) ◽  
pp. 1478-1491
Author(s):  
Debora J Mahushi ◽  
Revocatus L Machunda ◽  
Talam E Kibona
Keyword(s):  
Satellite Images ◽  
Forest Cover ◽  
Energy Sources ◽  
Cow Dung ◽  
Liquefied Petroleum Gas ◽  
Landsat Images ◽  
Wood Fuel ◽  
Energy Demands ◽  
Northern Tanzania ◽  
Questionnaire Surveys

Satellite images for the years 1987, 1997, 2002 and 2017, and questionnaire surveys were used to assess energy sources and demands as well as the impacts of wood fuel use to forest cover changes in Meru and Mwanga Districts. The major energy sources identified in the study areas include cow dung cake, firewood, charcoal, biogas, and liquefied petroleum gas. The total energy demands from these sources were 1400, 6289, 724 and 21 kg per day, respectively. Analysis from Landsat images showed variations in forest cover. The areas covered with forests in Meru District were found to be 1510, 1723, 1612 and 1327 ha for 1987, 1997, 2002 and 2017, respectively. The changes observed in Mwanga District were 31705, 31988, 17939 and 30960 ha for 1987, 1997, 2002 and 2017, respectively. From the findings it was observed that, the ongoing use of wood fuel in semi-arid areas of Meru and Mwanga Districts could deplete forests completely. The study concludes that charcoal and firewood consumptions are real threats to the long-term persistence of forests in Tanzania and proposes the use of renewable energy such as biogas for alleviating forest losses. Keywords: Biogas, energy sources, Satellite images

scholarly journals State and evolution of the African rainforests between 1990 and 2010

2013 ◽  
Vol 368 (1625) ◽  
pp. 20120300 ◽  
Author(s):  
Philippe Mayaux ◽  
Jean-François Pekel ◽  
Baudouin Desclée ◽  
François Donnay ◽  
Andrea Lupi ◽  
...  
Keyword(s):  
West Africa ◽  
Forest Cover ◽  
Central Africa ◽  
Congo Basin ◽  
Landsat Images ◽  
Deforestation Rate ◽  
Rural And Urban ◽  
Moderate Resolution ◽  
Underlying Causes ◽  
Moderate Resolution Imaging Spectroradiometer

This paper presents a map of Africa's rainforests for 2005. Derived from moderate resolution imaging spectroradiometer data at a spatial resolution of 250 m and with an overall accuracy of 84%, this map provides new levels of spatial and thematic detail. The map is accompanied by measurements of deforestation between 1990, 2000 and 2010 for West Africa, Central Africa and Madagascar derived from a systematic sample of Landsat images—imagery from equivalent platforms is used to fill gaps in the Landsat record. Net deforestation is estimated at 0.28% yr −1 for the period 1990–2000 and 0.14% yr −1 for the period 2000–2010. West Africa and Madagascar exhibit a much higher deforestation rate than the Congo Basin, for example, three times higher for West Africa and nine times higher for Madagascar. Analysis of variance over the Congo Basin is then used to show that expanding agriculture and increasing fuelwood demands are key drivers of deforestation in the region, whereas well-controlled timber exploitation programmes have little or no direct influence on forest-cover reduction at present. Rural and urban population concentrations and fluxes are also identified as strong underlying causes of deforestation in this study.

scholarly journals LAND COVER DYNAMICS AND LANDSCAPE STRUCTURE IN THE AREA SURROUNDING WATER RESERVOIRS, MOUNTAINOUS REGION OF RIO DE JANEIRO

FLORESTA ◽  
2020 ◽  
Vol 50 (4) ◽  
pp. 1808
Author(s):  
Lucas De Siqueira Cardinelli ◽  
José Marinaldo Gleriani ◽  
Sebastião Venâncio Martins
Keyword(s):  
Land Cover ◽  
Landscape Structure ◽  
Rio De Janeiro ◽  
Forest Cover ◽  
Water Area ◽  
Mountainous Region ◽  
Water Reservoirs ◽  
Landsat Images ◽  
Surrounding Water ◽  
Land Cover Dynamics

The aim of this study is to evaluate land cover dynamics and landscape structure in the area surrounding two water reservoirs built-in 2009 for energy production, in the mountainous region of the State of Rio de Janeiro (Serra Fluminense). The analysis was developed through the interpretation of Landsat images from 2003, 2009, and 2013, considering the following land cover classes: early successional forest, mid successional forest, pasture, pasture with shrubs and trees, geological outcrop, urban area, and water area. We used thematic maps to determine landscape metrics of size and proximity in the reservoirs catchment area and the Permanent Preservation Area (PPA). At catchment level, pasture was predominant, a consequence of the extensive livestock production carried out in the whole watershed. During the evaluated period, the forest area remained consistent, however, fragmented in many small patches of mid successional forest. The average patch area of mid successional forest is three times the size of the early successional forest patches. For neither forest land cover classes, no significant variations through time in area or isolation were identified. On the PPA, an overall reduction of the forest cover was registered before the construction of the reservoir. However, from 2009 to 2013, after the enclosure of PPA areas, the forest cover increased 35% via assisted natural regeneration, suggesting a high potential for cost-effective restoration in the region.

scholarly journals Snow Cover and Snow Persistence Changes in the Mocho-Choshuenco Volcano (Southern Chile) Derived From 35 Years of Landsat Satellite Images

2021 ◽  
Vol 9 ◽  
Author(s):  
Roberto O. Chávez ◽  
Verónica F. Briceño ◽  
José A. Lastra ◽  
Daniel Harris-Pascal ◽  
Sergio A. Estay
Keyword(s):  
Snow Cover ◽  
Satellite Images ◽  
Remote Sensing Data ◽  
Landsat Images ◽  
Microbial Composition ◽  
Mountain Areas ◽  
Pixel Resolution ◽  
Temperature Changes ◽  
Soil Microbial ◽  
Landsat Satellite

Mountain regions have experienced above-average warming in the 20th century and this trend is likely to continue. These accelerated temperature changes in alpine areas are causing reduced snowfall and changes in the timing of snowfall and melt. Snow is a critical component of alpine areas - it drives hibernation of animals, determines the length of the growing season for plants and the soil microbial composition. Thus, changes in snow patterns in mountain areas can have serious ecological consequences. Here we use 35 years of Landsat satellite images to study snow changes in the Mocho-Choshuenco Volcano in the Southern Andes of Chile. Landsat images have 30 m pixel resolution and a revisit period of 16 days. We calculated the total snow area in cloud-free Landsat scenes and the snow frequency per pixel, here called “snow persistence” for different periods and seasons. Permanent snow cover in summer was stable over a period of 30 years and decreased below 20 km2 from 2014 onward at middle elevations (1,530–2,000 m a.s.l.). This is confirmed by negative changes in snow persistence detected at the pixel level, concentrated in this altitudinal belt in summer and also in autumn. In winter and spring, negative changes in snow persistence are concentrated at lower elevations (1,200–1,530 m a.s.l.). Considering the snow persistence of the 1984–1990 period as a reference, the last period (2015–2019) is experiencing a −5.75 km2 reduction of permanent snow area (snow persistence > 95%) in summer, −8.75 km2 in autumn, −42.40 km2 in winter, and −18.23 km2 in spring. While permanent snow at the high elevational belt (>2,000 m a.s.l.) has not changed through the years, snow that used to be permanent in the middle elevational belt has become seasonal. In this study, we use a probabilistic snow persistence approach for identifying areas of snow reduction and potential changes in alpine vegetation. This approach permits a more efficient use of remote sensing data, increasing by three times the amount of usable scenes by including images with spatial gaps. Furthermore, we explore some ecological questions regarding alpine ecosystems that this method may help address in a global warming scenario.

scholarly journals Snow and Ice Studies By Thematic Mapper and Multispectral Scanner Landsat Images

1987 ◽  
Vol 9 ◽  
pp. 109-118 ◽  
Author(s):  
Olav Orheim ◽  
Baerbel K. Lucchitta
Keyword(s):  
Satellite Images ◽  
Thematic Mapper ◽  
Landsat Images ◽  
Snow Properties ◽  
Spectral Bands ◽  
Dronning Maud Land ◽  
Visible Wavelengths ◽  
Transverse Strains ◽  
Thermal Band ◽  
Snow And Ice

Digitally enhanced Landsat Thematic Mapper (TM) images of Antarctica reveal snow and ice features to a detail never seen before in satellite images. The six TM reflective spectral bands have a nominal spatial resolution of 30 m, compared to 80 m for the Multispectral Scanner (MSS). TM bands 2–4 are similar to the MSS bands. TM infra-red bands 5 and 7 discriminate better between clouds and snow than MSS or the lower TM bands. They also reveal snow features related to grain-size and possibly other snow properties. These features are not observed in the visible wavelengths. Large features such as flow lines show best in the MSS and lower TM bands. Their visibility is due to photometric effects on slopes. TM thermal band 6 has a resolution of 120 m. It shows ground radiation temperatures and may serve to detect liquid water and to discriminate between features having similar reflectivities in the other bands, such as blue ice.Repeated Landsat images can be used for sophisticated glaciological studies. By comparing images from 1975 and 1985, flow rates averaging 0.72 km a−1, and mean longitudinal and transverse strains of respectively 1.3 × 10 −4 a −1 and 130 × 10−4 a−1 have been measured for Jutulstraumen, Dronning Maud Land.

scholarly journals Bi-Temporal Analysis of Spatial Changes of Boreal Forest Cover and Species in Siberia for the Years 1985 and 2015

2020 ◽  
Vol 12 (24) ◽  
pp. 4116
Author(s):  
Lei Tian ◽  
Wenxue Fu
Keyword(s):  
Boreal Forest ◽  
Forest Cover ◽  
Coniferous Forest ◽  
Temporal Analysis ◽  
Quantitative Information ◽  
Forest Change ◽  
Landsat Images ◽  
Latitude Zone ◽  
Broad Leaved Forest ◽  
Leaved Forest

Boreal forest is a sensitive indicator of the influence of climate change. It can quantify the level and spatial divergence of forest change for forest resources and carbon cycle research. This study selected a typical boreal forest affected by few human activities as a research area, in Siberia, with a latitude span of 51°N–69°N. A total of 150 Landsat images of this area acquired in 1985 and 2015 were collected. A hierarchical classification approach was first established to retrieve the information of forest cover and species. The forested and nonforested lands were discriminated by the decision tree method and, furthermore, the forested land was classified to broad-leaved and coniferous forests by a random forest algorithm. The overall accuracy was 90.37%, which indicates the validity of the approach. Finally, the quantitative information of the forest cover and species changes in each latitude zone of every 2° was analyzed. The results show that the overall boreal forest cover increased by 5.11% over the past three decades, with broad-leaved forest increasing by 3.54% and coniferous forest increasing by 1.57%. In addition, boreal forest increased in every latitude zone, and the spatial divergence of the changes of the boreal forest cover and species in different latitude zones were significant. Finally, broad-leaved forest increased more rapidly than coniferous forest, and the greatest increase, of up to 5.77%, occurred in the zone of 55°N–57°N.

scholarly journals Cocoa Production and Forest Dynamics in Ivory Coast from 1985 to 2019

Land ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 524
Author(s):  
Barima Yao Sadaiou Sabas ◽  
Konan Gislain Danmo ◽  
Kouakou Akoua Tamia Madeleine ◽  
Bogaert Jan
Keyword(s):  
Forest Dynamics ◽  
Ivory Coast ◽  
Forest Cover ◽  
Forest Area ◽  
Native People ◽  
Population Increase ◽  
Landsat Images ◽  
The West ◽  
South West ◽  
Cocoa Production

The cocoa economy of Ivory Coast started in the eastern part of the country in the 1970s and spread to the central-western and then south-western regions. For nearly a decade, it has been in the West of Ivory Coast with a population increase caused by large waves of migration. This study aims to determine different factors explaining dynamics of the cocoa economy from the East to West of Ivory Coast. The method adopted consisted of processing Landsat images from 1985–2018 and an individual survey of 278 heads of households. The results obtained showed that the development of the cocoa economy led forest cover degradation with a total loss estimated at 60.80%, 46.39%, 20.76% and 51.18% of forest area in the East, Centre-West, South-West and West, respectively. The creation of new cocoa farms in the West of Ivory Coast is governed by non-native people (51.13%) settled between 2010 and 2018. About 41% of these producers come mainly from the Centre-West (25%) and the South-West (16%). In addition, 29% of producers come from the West of Ivory Coast. Despite the abiotic characteristics being considered unfavourable, the west of Ivory Coast is in the process of becoming the country’s new zone of high cocoa production.

scholarly journals The state of lemur conservation in south-eastern Madagascar: population and habitat assessments for diurnal and cathemeral lemurs using surveys, satellite imagery and GIS

Oryx ◽  
2005 ◽  
Vol 39 (2) ◽  
pp. 204-218 ◽  
Author(s):  
Mitchell T. Irwin ◽  
Steig E. Johnson ◽  
Patricia C. Wright
Keyword(s):  
Information System ◽  
Population Density ◽  
Satellite Images ◽  
Forest Cover ◽  
Geographical Information ◽  
Human Populations ◽  
Ecological Diversity ◽  
Geographic Ranges ◽  
South Eastern ◽  
Face Threats

The unique primates of south-eastern Madagascar face threats from growing human populations. The country's extant primates already represent only a subset of the taxonomic and ecological diversity existing a few thousand years ago. To prevent further losses remaining taxa must be subjected to effective monitoring programmes that directly inform conservation efforts. We offer a necessary first step: revision of geographic ranges and quantification of habitat area and population size for diurnal and cathemeral (active during both day and night) lemurs. Recent satellite images are used to develop a forest cover geographical information system, and censuses are used to establish range boundaries and develop estimates of population density and size. These assessments are used to identify regions and taxa at risk, and will be a useful baseline for future monitoring of habitat and populations. Precise estimates are impossible for patchily-distributed taxa (especially Hapalemur aureus, H. simus and Varecia variegata variegata); these taxa require more sophisticated modelling.

The effect of forest fire on mass movement in Lebanese mountainous areas

2014 ◽  
Vol 23 (6) ◽  
pp. 845
Author(s):  
Rouba Ziadé ◽  
Chadi Abdallah ◽  
Nicolas Baghdadi
Keyword(s):  
Forest Fire ◽  
Satellite Images ◽  
Mass Movement ◽  
Potential Effect ◽  
Burn Severity ◽  
Susceptibility Map ◽  
Mass Movements ◽  
Mountainous Areas ◽  
Effect Factors ◽  
Landsat Images

Mass movements are major hazards that threaten natural and human environments. In Lebanon, the occurrence of mass movements increased by almost 60% between 1956 and 2008. Forest fire has emerged as an additional hazard: it destroyed over 25% of Lebanon’s forests in a period less than 40 years. This paper investigates the potential effect of forest fire on the occurrence of mass movements in the Damour and Nahr Ibrahim watersheds of Lebanon. Mass movement and forest fire inventory maps were produced through remote sensing using aerial and satellite images. Forest fire was included as an additional factor in mass movement induction, and its effect was quantified from Landsat images through the normalised burn ratio (NBR) index. A field study was conducted to substantiate the mass movement inventory and NBR maps. Following the standardisation of the effect factors into layers using geographic information systems, the weight factor of each layer for inducing mass movements was evaluated using the modified InfoVal method, and a mass movement susceptibility map was generated. Exceeded only by changes in land cover, the NBR produced the highest weights, making forest fire burn severity the second highest factor influencing mass movement occurrence in the study areas.

scholarly journals COMPARATIVE STUDY OF THE EMISSION CHARACTERIZATION OF BIOGAS AND CONVENTIONAL COOKING GAS IN NIGERIA

2021 ◽  
pp. 1-8
Author(s):  
Titus Adegboye ◽  
Iyiola Oluwaleye
Keyword(s):  
Natural Gas ◽  
Comparative Study ◽  
Cow Dung ◽  
Liquefied Petroleum Gas ◽  
Gas Analyzer ◽  
Viable Option ◽  
Compressed Natural Gas ◽  
Energy Mix

Household fuel refers to any material that is used to produce heat or power by burning. Some of the household fuel used in Nigeria includes: biomass, charcoal, kerosene, CNG (Compressed natural gas), LPG (liquefied petroleum gas), electricity. Biogas is relatively new and emerging as a viable option. In this study, biogas was produced using cow dung and the emission characterization of biogas and that of LPG was compared using a Gasboard model 5020H gas analyzer. Results of biogas emission is as follows; CO: 0.01%Vol , CO2: 0.14 %Vol, HC: 0010 ppm, NOx: 0002 ppm while LPG gives the following; CO: 0.30%Vol , CO2: 1.88 %Vol, HC: 0003 ppm, NOx: 0007 ppm. Recommendation was made for the inclusion of biogas in Nigeria energy mix because of its relatively better emission.

scholarly journals Distribution and habitat preferences of Sumatran elephant (Elephas maximus sumatranus) in Riau, Indonesia

2018 ◽  
Vol 20 (1) ◽  
pp. 226-235
Author(s):  
YOHANES WISHNU SUKMANTORO ◽  
HADI S. ALIKODRA ◽  
AGUS P. KARTONO ◽  
EFRANSJAH EFRANSJAH
Keyword(s):  
Habitat Selection ◽  
Land Cover ◽  
Oil Palm ◽  
Forest Cover ◽  
Habitat Preferences ◽  
Elephas Maximus ◽  
Plantation Forest ◽  
Color Analysis ◽  
Minimum Convex Polygon ◽  
Landsat Images

Sukmantoro YW, Alikodra HS, Kartono AP, Efransjah. 2019. Distribution and habitat preferences of Sumatran elephant (Elephas maximus sumatranus) in Riau, Indonesia. Biodiversitas 20: 226-235. The research on elephant distribution and habitat preference was carried out in two locations Balai Raja and Tesso Nilo, Riau Province, Indonesia on 2012-2016. Three GPS Collars were installed on one individual adult female at Balai Raja (Desma) and two individuals at Tesso Nilo (Angelina and Butet). For the elephants’ habitat, the forest cover identification was performed by spectral color analysis on the 8 ETM+ Landsat images and resulted in land cover detail on MCP (Minimum Convex Polygon), and 50% and 95% fix kernel density of movement of the elephant including in the morning, the day and the night. Based on MCP estimation, Desma habitat area was 328.86 km2, while Angelina and Butet were 632.57 km2 and 701.60 km2, respectively. Land cover in MCP indicated that the oil palm, mixed agriculture, and rubber were dominantly areas used by Desma, while acacia, forest and oil palm plantation were dominantly area used by Angelina and Butet. In habitat preferences, Desma preferred forests and swamp areas to day activity. However, Angelina and Butet selected acacia plantation, forest, infrastructures such as the mills and land opening as the location of movement. Water bodies and shrub were not widely used for the elephants’ activities. This study indicated that the pattern of habitat selection is a strategy for elephants to avoid conflict with the human. Although resources are limited, the habitat selection can reduce conflict incidence.

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