scholarly journals Mapping floristic communities in Southern Africa savannas, Mozambique

Rodriguésia ◽  
2021 ◽  
Vol 72 ◽  
Author(s):  
Aurélio de Jesus Rodrigues Pais ◽  
Natasha Sofia Ribeiro ◽  
Rubens Manoel dos Santos
Keyword(s):  
Landsat 8 ◽  
Kappa Index ◽  
Human Occupation ◽  
Floristic Survey ◽  
Colophospermum Mopane ◽  
Representative Species ◽  
Ecological Importance ◽  
Shallow Soils ◽  
Combretum Apiculatum ◽  
Land Use And Cover

Abstract The present study was carried out in Limpopo National Park (LNP) with the objective to map floristic communities that occur inside the park. Three (3) Landsat 8 satellite images were obtained by Operational Land Imager (OLI) and Thermal Infrared Sensor (TIRS) tools and were pre-processed and classified, culminating in six (6) types of land use and cover. The floristic survey consisted of stratified sampling in three (3) main LNP landscapes types, namely landscape of limestone soils, landscape of rhyolite shallow soils and landscape of deep sandy soils. The final map presents 13 floristic communities identified by the names of greatest value of ecological importance (IVI) species. The community of Terminalia sericea / Combretum apiculatum / Guibourtia conjugata / Colophospermum mopane presented a larger occurrence area. Colophospermum mopane was the most representative species among the mapped communities, mostly occurring in association with other species. The overall accuracy was 74% and the Kappa index was 68%, thus giving a good rating. The mapping also showed that human occupied areas are larger than some floristic communities areas, so we suggest that these smaller communities, should be given priority actions for their conservation, especially those without human occupation.

scholarly journals AVALIAÇÃO DA QUALIDADE DE CLASSIFICADORES DE IMAGENS LANDSAT 8 EM AMBIENTE COMPUTACIONAL SAGA GIS PARA MAPEAMENTO DE COBERTURA DA TERRA NO BIOMA CERRADO

2021 ◽  
Vol 7 (20) ◽  
pp. 202128
Author(s):  
Antonia Sueli Silva Sousa ◽  
Paulo Roberto Mendes Pereira ◽  
Audivan Ribeiro Garcês Júnior
Keyword(s):  
Image Processing ◽  
Digital Image ◽  
Landsat 8 ◽  
Kappa Index ◽  
El Sistema ◽  
Computer Environment ◽  
Processing Accuracy ◽  
Attribute Extraction ◽  
Global Accuracy ◽  
Object Of Study

QUALITY ASSESSMENT OF LANDSAT 8 IMAGE CLASSIFIERS IN A SAGA GIS COMPUTER ENVIRONMENT FOR LAND COVERING MAPPING IN THE CERRADO BIOMEEVALUACIÓN DE LA CALIDAD DE LOS CLASIFICADORES DE IMAGEN LANDSAT 8 EN UN ENTORNO COMPUTACIONAL SAGA GIS PARA EL MAPEO DE COBERTURA DE TIERRAS EN EL BIOMA DE CERRADORESUMOUma das principais aplicações das imagens de satélites é a caracterização da cobertura terrestre, que a partir do uso de técnicas de classificação permite monitorar as transformações espaciais da superfície terrestre. O Sistema Automatizado de Análise Geociêntífica – Saga Gis apresenta um conjunto de ferramentas voltado à análise geográfica, incluindo pacotes de classificação de imagens digitais, onde se destacam os classificadores: Maxver, Mahalanobis, distância mínima, paralelepípedo. O objetivo deste artigo é avaliar o potencial dos classificadores de imagens do Saga Gis no bioma Cerrado, sendo objeto de estudo, o município de Brejo-MA. Foi utilizada uma imagem Landsat 8 de 2017, com resolução espacial de 30 metros. A metodologia consistiu na aplicação de um conjunto de técnicas de tratamento digital de imagens, segmentação, extração de atributos e classificação. A análise dos dados pautou-se na comparação visual e análise da exatidão global e de índice Kappa. O classificador Maxver apresentou os melhores resultados para o Kappa e exatidão global, já os piores valores foram associados ao classificador paralelepípedo.Palavras-chave: Geotecnologia; Processamento de Imagem; Acurácia, Mapeamento. ABSTRACTOne of the main applications of satellite images is the characterization of terrestrial coverage, which from the use of classification techniques allows to monitor the spatial transformations of the terrestrial surface. The System for Automated Geoscientific Analyzes-Saga Gis presents a set of tools aimed at geographic analysis, including digital image classification packages, in which the classifiers stand out: Maxver, Mahalanobis, minimum distance, parallelepiped. The objective of this article is to evaluate the potential of the Saga Gis image classifiers in the Cerrado biome, being the object of study, the municipality of Brejo-MA. It was to use a Landsat 8 image (2017), with a spatial resolution of 30 meters. The methodology consisted of applying a set of techniques for digital image processing, segmentation, attribute extraction and classification. Data analysis was based on visual comparison and analysis of global accuracy and Kappa index. The Maxver classifier presented the best results for Kappa and overall accuracy, whereas the worst values were associated with the parallelepiped classifier.Keywords: Geotechnology; Image Processing; Accuracy; Mapping.RESUMENUna de las principales aplicaciones de las imágenes de satélite es la caracterización de la cobertura terrestre, que, a partir del uso de técnicas de clasificación, permite el seguimiento de las transformaciones espaciales de la superficie terrestre. El Sistema de Análisis Geocientífico Automatizado (Saga Gis) presenta un conjunto de herramientas orientadas al análisis geográfico, que incluyen paquetes de clasificación de imágenes digitales, en los que destacan los clasificadores: Maxver, Mahalanobis, distancia mínima, paralelepípedo. El objetivo de este artículo es evaluar el potencial de los clasificadores de imágenes Saga Gis en el bioma del Cerrado, siendo objeto de estudio, el municipio de Brejo-MA. Se utilizó una imagen Landsat 8 de 2017 con una resolución espacial de 30 metros. La metodología consistió en aplicar un conjunto de técnicas de procesamiento, segmentación, extracción de atributos y clasificación de imágenes digitales. El análisis de los datos se basó en la comparación visual y el análisis de la precisión global y el índice Kappa. El clasificador Maxver presentó los mejores resultados para Kappa y precisión general, mientras que los peores valores se asociaron con el clasificador paralelepípedo.Palabras clave: Geotecnología; Procesamiento de imágenes; Precisión; Mapeo.

A study of wood use for fuel and building in an area of Gazankulu

Bothalia ◽  
1983 ◽  
Vol 14 (2) ◽  
pp. 245-257 ◽  
Author(s):  
C. A. Liengme
Keyword(s):  
Colophospermum Mopane ◽  
Building Timber ◽  
The Mean ◽  
And Storage ◽  
Combretum Apiculatum ◽  
Do So

The utilization of wood for fuel and building timber was studied in a 13 000 ha area of Gazankulu, near Giyani. Headloads of firewood brought in by eight of the 978 families present were monitored during six periods in a year. The two most important sources of firewood are  Colophospermum mopane and  Combretum apiculatum. Firewood consumption is estimated at an average of 14,9 kg per family per day. The annual demand for firewood in the whole study area is, therefore, approximately 5 300 tonnes. Living-huts and storage-huts in the process of being built were examined. The mean volumes of wood in living-huts and typical storage-huts are 1,30 m3 and1,09 m3, respectively. 89 living- and 80 storage-huts were built in a year. The demand for finished timber in the study area in that year was approximately 231 tonnes. Timber use has not yet outstripped production, but it will do so soon if alternative timber sources are not provided.

scholarly journals Agricultural land use and cover change in the Cerrado/Amazon ecotone: A case study of the upper Teles Pires River basin

2018 ◽  
Vol 48 (2) ◽  
pp. 168-177 ◽  
Author(s):  
Ana Paula Sousa Rodrigues ZAIATZ ◽  
Cornélio Alberto ZOLIN ◽  
Laurimar Goncalves VENDRUSCULO ◽  
Tarcio Rocha LOPES ◽  
Janaina PAULINO
Keyword(s):  
Land Use ◽  
River Basin ◽  
Large Scale ◽  
Agricultural Land ◽  
Temporal Dynamics ◽  
Direct Conversion ◽  
Landsat 8 ◽  
Error Matrix ◽  
Mato Grosso ◽  
Land Use And Cover

ABSTRACT The upper Teles Pires River basin is a key hydrological resource for the state of Mato Grosso, but has suffered rapid land use and cover change. The basin includes areas of Cerrado biome, as well as transitional areas between the Amazon and Cerrado vegetation types, with intensive large-scale agriculture widely-spread throughout the region. The objective of this study was to explore the spatial and temporal dynamics of land use and cover change from 1986 to 2014 in the upper Teles Pires basin using remote sensing and GIS techniques. TM (Thematic Mapper) and TIRS (Thermal Infrared Sensor) sensor images aboard the Landsat 5 and Landsat 8, respectively, were employed for supervised classification using the “Classification Workflow” in ENVI 5.0. To evaluate classification accuracy, an error matrix was generated, and the Kappa, overall accuracy, errors of omission and commission, user accuracy and producer accuracy indexes calculated. The classes showing greatest variation across the study period were “Agriculture” and “Rainforest”. Results indicated that deforested areas are often replaced by pasture and then by agriculture, while direct conversion of forest to agriculture occured less frequently. The indices with satisfactory accuracy levels included the Kappa and Global indices, which showed accuracy levels above 80% for all study years. In addition, the producer and user accuracy indices ranged from 59-100% and 68-100%, while the errors of omission and commission ranged from 0-32% and 0-40.6%, respectively.

scholarly journals The impact of the provision of water for game on the woody vegetation around a dam in the Kruger National Park

Koedoe ◽  
1991 ◽  
Vol 34 (2) ◽  
Author(s):  
I. Thrash ◽  
P.J. Nel ◽  
G.K. Theron ◽  
J. Du P. Bothma
Keyword(s):  
Relative Density ◽  
Woody Plants ◽  
National Park ◽  
Dominant Species ◽  
Canopy Cover ◽  
Kruger National Park ◽  
Woody Vegetation ◽  
Colophospermum Mopane ◽  
The Impact ◽  
Combretum Apiculatum

Quantitative inventory surveys were done on the woody vegetation in permanently marked plots at distance intervals from the Wik-en-Weeg Dam, Kruger National Park, in 1973. The surveys were repeated in 1990 so that changes in the community composition, the density and the canopy cover and the survival of the woody vegetation could be determined in relation to distance from the dam. Relationships with distance from the dam were shown for the relative density ofCombretumapiculatum in all height classes, the relative canopy cover of the second height class of woody plants, the relative canopy cover of C. apiculatum plants, the survival of all height classes of woody plants and the survival of C. apiculatum and Colophospermum mopane plants. It was concluded that the provision of water for game at the Wik-en-Weeg Dam had an impact on the woody vegetation in the vicinity. The relationships of parameters of the two dominant species, Combretum apiculatum and Colophospermum mopane, with distance from the dam were compared. Combretum apiculatum parameters were more sensitive to impact associated with the dam than those of Colophospermum mopane.

scholarly journals The tribes Acacieae and Ingeae (Leguminosae: Caesalpinioideae) in the Environmental Protection Area Serra Branca, Raso da Catarina, Jeremoabo, Bahia, Brazil

2019 ◽  
Vol 19 (4) ◽  
Author(s):  
Aline Franco Sampaio Brito ◽  
Élvia Rodrigues de Souza ◽  
Adilva de Souza Conceição
Keyword(s):  
Environmental Protection ◽  
Geographical Distribution ◽  
Clay Soils ◽  
Floristic Survey ◽  
Phenological Data ◽  
Taxonomic Treatment ◽  
Sandy Clay ◽  
Representative Species ◽  
Environmental Protection Area ◽  
Protection Area

Abstract: Leguminosae includes six subfamilies, where the traditionally recognised subfamily Mimosoideae was accepted as a distinct clade included within the recircumscribed subfamily Caesalpinioideae, called informally as Mimosoid clade. The representatives of the tribes Acacieae and Ingeae can be differentiated principally in terms of the patterns of their stamens, being free in Acacieae and monadelphous in Ingeae. The floristic survey of Acacieae and Ingeae in the Environmental Protection Area Serra Branca included analysis of specimens collected from June 2011 to September 2012. The analyses were supplemented with dried collections from the following herbaria: ALCB, HRB and HUEFS. Ten species were cataloged, distributed among four genera of Ingeae: Calliandra Benth. (1 sp.), Chloroleucon (Benth.) Britton & Rose ex Record (1 sp.), Enterolobium Mart. (1 sp.), Pithecellobium Mart. (1 sp.); and one genus of Acacieae: Senegalia Raf. (6 spp.). The most representative species were Calliandra aeschynomenoides Benth. associated with sandy and stony soils and Chloroleucon foliolosum (Benth.) G.P.Lewis and Senegalia bahiensis (Benth.) Seigler & Ebinger growing on sandy-clay soils. The taxonomic treatment includes a key for the identification, descriptions, illustrations, photos, data of the geographical distribution phenological data and comments about the species.

scholarly journals Surface albedo in different land-use and cover types in Amazon forest region

2018 ◽  
Vol 13 (2) ◽  
pp. 1 ◽  
Author(s):  
Thiago De Oliveira Faria ◽  
Thiago Rangel Rodrigues ◽  
Leone Francisco Amorim Curado ◽  
Denilton Carlos Gaio ◽  
José De Souza Nogueira
Keyword(s):  
Land Use ◽  
Surface Albedo ◽  
Landsat Imagery ◽  
Important Variable ◽  
Google Earth ◽  
Transitional Region ◽  
Amazon Forest ◽  
Human Occupation ◽  
Forest Region ◽  
Land Use And Cover

Albedo is the portion of energy from the Sun that is reflected by the earth's surface, thus being an important variable that controls climate and energy processes on Earth. Surface albedo is directly related to the characteristics of the Earth’s surface materials, making it a useful parameter to evaluate the effects of original soil cover replacement due to human occupation. This study evaluated the changes in the surface albedo values due to the conversion of vegetation to other land uses and to analyze the applicability of the use of albedo in the spatial delimitation of land-use classes in the transitional region between the Cerrado and Amazon biomes. Surface albedo measurements were obtained from processing of Landsat Thematic Mapper data in the Geographic Information System (GIS), and land-use information were collected using Google Earth high-resolution images. The results show that human activities such as the cultivation of crops and burning have contributed substantially to variations in the surface albedo, and that albedo estimates from Landsat imagery have the potential to help in the recognition and delimitation of features of land use and cover.

scholarly journals A floristic survey of angiosperm species occurring at three landscapes of the Central Amazon várzea, Brazil

Check List ◽  
2015 ◽  
Vol 11 (6) ◽  
pp. 1789 ◽  
Author(s):  
Bruno Garcia Luize ◽  
Eduardo Martins Venticinque ◽  
Thiago Sanna Freire Silva ◽  
Evlyn Marcia Leão de Moraes Novo
Keyword(s):  
Amazon Basin ◽  
Forest Degradation ◽  
Floodplain Forests ◽  
Human Occupation ◽  
Floristic Survey ◽  
Central Amazon ◽  
Botanical Knowledge ◽  
Degradation Rates ◽  
Floods And Droughts ◽  
Angiosperm Species

The Amazonian floodplains harbor highly diverse wetland forests, with angiosperms adapted to survive extreme floods and droughts. About 14% of the Amazon Basin is covered by floodplains, which are fundamental to river productivity, biogeochemical cycling and trophic flow, and have been subject to human occupation since Pre-Colombian times. The botanical knowledge about these forests is still incomplete, and current forest degradation rates are much higher than the rate of new botanical surveys. Herein we report the results of three years of botanical surveys in floodplain forests of the Central Amazon. This checklist contains 432 tree species comprising 193 genera and 57 families. The most represented families are Fabaceae, Myrtaceae, Lauraceae, Sapotaceae, Annonaceae, and Moraceae representing 53% of the identified species. This checklist also documents the occurrence of approximately 236 species that have been rarely recorded as occurring in white-water floodplain forests.

scholarly journals Possibility for Identifying/Extracting Rock Outcrop Using Landsat 8 OLI/TIRS - Case Study of Thua Thien Hue Province

2020 ◽  
Vol 36 (3) ◽  
Author(s):  
Nguyen Quang Tuan ◽  
Do Thi Viet Huong ◽  
Doan Ngoc Nguyen Phong ◽  
Nguyen Dinh Van
Keyword(s):  
Vegetation Index ◽  
Normalized Difference Vegetation Index ◽  
Satellite Image ◽  
Object Orientation ◽  
Image Method ◽  
Landsat 8 ◽  
Landsat 8 Oli ◽  
Kappa Index ◽  
Exposed Rock ◽  
Ratio Image

This paper approaches the ratio image method to extract the exposed rock information from the Landsat 8 OLI/TIRS satellite image (2019) according to the object orientation classification. Combining automatic interpretation and interpretation through threshold of image index values according to interpretation key the object orientation classification to separate soil object containing exposed rock and no exposed rock in Thua Thien Hue province. Using the Topsoil Grain Size Index (TGSI), the Normalized Difference Vegetation Index (NDVI), the Normalized Difference Built-up Index (NDBI) and other related analytical problems have identified 40 exposed rock storage areas in the study area. The results have been verified in the field and the Kappa index is 85.10%.

scholarly journals Impacts of Land Use and Cover Changes on Transhumant Pastoralism in Sudanian Zones of Burkina Faso, West Africa

2018 ◽  
Vol 5 (4) ◽  
pp. 90
Author(s):  
Charles L. Sanou ◽  
Nouhoun Zampaligré ◽  
Daniel N. Tsado ◽  
André Kiema ◽  
Yssouf Sieza
Keyword(s):  
Land Use ◽  
Burkina Faso ◽  
Average Rate ◽  
Accuracy Assessment ◽  
Animal Husbandry ◽  
Thematic Mapper ◽  
Landsat 8 ◽  
Land Uses ◽  
Landsat Images ◽  
Land Use And Cover

This research aimed to investigate how the rapid land use and cover changes is affecting pastoral resources and practices within Kompienga province in Sudanian zone of Burkina Faso. To achieve this aim, Landsat images data of years 1989, 2001, 2013 and 2015 were retrieved and analysed. Images were acquired following the path 193 and row 52, from Landsat-5 Thematic Mapper (TM), Landsat-7 Enhanced Thematic Mapper Plus (ETM+) and Landsat-8 Operational Land Imager (OLI). Images processing were done using 350 training sample for both; the purpose of supervised classification and accuracy assessment. Random Forest Algorithm (RFA) procedures in R-Software (version 3.3.2) were used for images classification. Furthermore, survey data were collected through group discussions and individual interviews with a 271 head of household respondents (pastoralists and agro-pastoralists) to investigate respondents’ perceptions on land uses and covers changes and its impacts on their pastoral and agro pastoral resources and animal husbandry practices. Results showed that Land use dynamics was characterized by an increase in croplands at an average rate of 46.7 % per year, between 1989 and 2015. On the contrary a decline of pasture lands was observed since 2001 at an average rate of 6.0 % per year. Similar trends in land uses changes were observed by interviewed respondents who depicted an increase in cropping lands (98.5 % of respondents) to the detriment of pasture lands (97.8 % of respondents). To overcome these land use/land cover changes and it subsequent consequences, respondent pastoralists and agro pastoralists have developed local adaptations strategies. Thus, some measures are still needed at government level to sustain local pastoralist and agro-pastoralist efforts and strengthen their adaptive capacity.

scholarly journals REMOTE SENSING IMAGE TIME SERIES METRICS FOR DISTINCTION BETWEEN PASTURE AND CROPLANDS USING THE RANDOM FOREST CLASSIFIER

2020 ◽  
Vol XLII-3/W12-2020 ◽  
pp. 557-562
Author(s):  
M. A. A. Rodrigues ◽  
H. N. Bendini ◽  
A. R. Soares ◽  
T. S. Körting ◽  
L. M. G. Fonseca
Keyword(s):  
Remote Sensing ◽  
Time Series ◽  
Random Forest ◽  
Landsat 8 ◽  
Kappa Index ◽  
Object Based ◽  
One Year ◽  
Global Accuracy ◽  
Rural Production ◽  
Potential Use

Abstract. Pasture and croplands play an important role in Brazil’s economic and political scenarios, once its PIB (Raw Internal Product) is mainly based on what is exported from the rural production, such as meat and soybean, and government, with its regulations, is part-responsible for the establishment and maintaining of the conditions so that the trades can go well. In addition, these two types of land use correspond together to aprox. one third of the country extension. Moreover, frequently lands occupation is subject of discussion concerning its potential use for the reason of conflicts including Brazilian traditional communities, landless people and big farmers. Considering it, mapping pasture and croplands accurately is crucial for the country administration, in both economic and political spheres. Certainly, remote sensing is the very manner to tackle this issue, although this may not be an easy task due to the spectral similarity between these patterns. This work, hence, aims to distinct pasture from croplands in an experimental subset area of Brazilian Cerrado biome, using remote sensing metric images derived from one-year time series of the Landsat 8 products. In order to achieve this goal, we utilized six bands of the OLI sensor and calculated seven metrics, attaining a compiled dataset with 42 layers. We performed an object-based supervised classification with the Random Forest algorithm, considering both spectral and geometrical attributes. Results showed global accuracy of 80%, with Kappa index of 0.6, and the potential time series have in separating targets spectrally similar.

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