Classificação de áreas semiáridas e subúmidas secas utilizando diferentes índices climáticos

As delimitações das áreas semiáridas do Nordeste do Brasil e norte de Minas Gerais podem apresentar grandes diferenças conforme os métodos de classificação climática e de estimativa da evapotranspiração potencial (ET0) utilizados. Para demostra esta afirmação de forma quantitativa, nesta pesquisa, delimitou-se as áreas semiáridas usando dois métodos de classificação climática (1) índice efetivo de umidade de Thornthwaite (Im) e (2) índice de aridez do Programa das Nações Unidas para o Meio Ambiente (IaUNEP), enquanto, para a estimativa da ET0 usou-se os métodos de (1) Thornthwaite e (2) Penman-Monteith-FAO (PMF), totalizando quatro diferentes configurações de delimitações de áreas semiáridas. Com a utilização de Im observou-se um aumento do grau de aridez e de áreas semiáridas quando comparado com os resultados obtidos com o uso de IaUNEP. Do mesmo modo, ao usar a estimativa de ET0 pelo método PMF verifica-se um aumento da aridez e das terras semiáridas em comparação com a ET0 calculada por Thornthwaite. Como o método PMF é geralmente reconhecido como um método padrão para estimativa da ET0. Portanto, é possível certificar que o grau de aridez e de terras semiáridas no Nordeste do Brasil são mais elevados do que aqueles mostrados nos estudos com a estimativa de ET0 por Thornthwaite. Classification of semi-árid and sub-humid sreas using different climate indexes A B S T R A C TThe delimitations of semi-arid areas in the Northeast of Brazil and northern Minas Gerais can present great differences according to the methods of climatic classification and estimation of potential evapotranspiration (ET0) used. To demonstrate this statement in a quantitative way, in this research, we used two different methods of climate classification: (1) the moisture index of Thornthwaite (Im) and (2) aridity index of the United Nations Environment Program (IaUNEP), as well as, two methods to estimate ET0: of (1) Thornthwaite and (2) Penman-Monteith-FAO (PMF), totaling four different configurations of delimitations of semi-arid areas. As the use of Im an increase in the degree of aridity and semi-arid areas was observed when compared with the results obtained as the use of IaUNEP. Similarly, when using the ET0 estimate using the PMF method, there is an increase in aridity and semi-arid land compared to the ET0 calculated by Thornthwaite. As the PMF method is generally recognized as a standard method for estimating ET0. Therefore, it is possible to affirm that the degree of aridity and semi-arid lands in Northeast Brazil are higher than those shown in studies with the estimate of ET0 by Thornthwaite. Keywords: Semiarid, climatic classification, potential evapotranspiration

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Classification of Arid & Semi-Arid Areas: A Case Study in Western Australia

ANU Undergraduate Research Journal ◽

10.22459/aurj.05.2013.07 ◽

2013 ◽

Vol 5 ◽

Cited By ~ 1

Author(s):

Guy Leech

Keyword(s):

Western Australia ◽

Arid Areas ◽

Semi Arid

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Agroclimatic zonation of Tigray region of Ethiopia based on aridity index and traditional agro-climatic zones

Journal of Agrometeorology ◽

10.54386/jam.v21i2.229 ◽

2021 ◽

Vol 21 (2) ◽

pp. 176-181

Author(s):

H. HAFTOM ◽

A. HAFTU ◽

K. GOITOM ◽

H. MESERET

Keyword(s):

Potential Evapotranspiration ◽

Aridity Index ◽

Climate Data ◽

Climate Services ◽

Climatic Zones ◽

Tigray Region ◽

Agroclimatic Zone ◽

Elevation Model ◽

Agroclimatic Zones ◽

Semi Arid

The aim of this study was to identify the agroclimatic zones of Tigray region based on aridity index and traditional agroclimatic zone using 37-year (1981-2017) spatial climate data downloaded for Tigray region from Climate Hazards Group InfraRed Precipitation with Station data (CHIRPS) for rainfall and from Enhancing National Climate Services (ENACTS) data for temperature. Arc map 10.3 was used for mapping of all climatic variables and zonation of agro-climatic zones. Potential evapotranspiration (PET) was computed based on Hargreaves formula and the aridity index was computed. Besides, the digital elevation model was downloaded from ASTER data. The aridity map of Tigray divided into three index zones (0.03-0.2, 0.2–0.5 and 0.5–0.65) and five traditional agro-climate zones (<1500,1500-2000,2000- 2500, 2500-3000, >3000 m.a.s.l.) were overlaid, which divided entire region of Tigray into fifteen agroclimatic zones. Hot semi-arid, warm semi-arid, tepid semi-arid and hot arid were the dominant zones in the region.

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Variação do índice de aridez e tendência climática à desertificação para a região semiárida do nordeste brasileiro (Variation of aridity index and climatic trend to desertification for the semi-arid region of the Brazilian Northeast)

Revista Brasileira de Geografia Física ◽

10.26848/rbgf.v10.4.p1014-1026 ◽

2017 ◽

Vol 10 (4) ◽

pp. 1014 ◽

Cited By ~ 1

Author(s):

Iug Lopes ◽

Saulo Medrado dos Santos ◽

Brauliro Gonçalves Leal ◽

Juliana Maria Medrado de Melo

Keyword(s):

Arid Region ◽

Aridity Index ◽

Northeast Brazil ◽

Climatic Trend ◽

Target Region ◽

Semi Arid Region ◽

Aridity Indices ◽

Brazilian Northeast ◽

Semi Arid

Uma das formas mais simples e aplicadas para a verificação da Tendência a Desertificação (TD) é através dos Índices de Aridez (IA). Assim, com a possibilidade de verificação da situação do IA e da TD na Região Semiárida do Nordeste, o objetivo foi a investigação da variação do IA e suas classificações, ao longo do período de 1961 a 2015 (em séries temporais de 30 anos), além TD para a região alvo do estudo. É maioria unânime que está ocorrendo a redução do IA para a região semiárida do Nordeste, sendo que cada estado apresenta uma situação peculiar e possível justificativa para o que está ocorrendo. Apesar de mudanças do IA, em muitas localidades, observou-se que não ocorreu alterações na classificação a Tendência a Desertificação, porém apresentam a maior tendência desertificação e a sua é classificação é alta. Verificou-se que também é necessário o aprofundamento deste estudo, com mais variáveis e com o uso da modelagem numérica e de tendência no que diz respeito à avaliação da desertificação para algumas regiões que foram pouco conclusivas do Semiárido do Nordeste. A B S T R A C TOne of the most useful and applied forms for verification of the Desertification Trend (TD) is through the calculation of the Aridity Indices (IA). Thus, the present work uses such methodology to verify the situation of IA and TD in the semi-arid region of Northeast Brazil. The objective was to investigate the variation of AI and its classifications over the period from 1961 to 2015, using a time series of 30 years, in addition to TD for the target region of the study. It is a consensus in the literature the occurrence of IA reduction for the semi-arid region of the Northeast, with each state presenting a peculiar situation and possible justification for the occurrence. With the results was possible to observe that in spite of changes of the IA in many localities, it was observed that there were no changes in the classification of the Tendency to Desertification. It was also verified the need to deepen these studies using climatic variables, with the use of more variables and with the use of numerical and trend modeling with regard to the evaluation of desertification for some regions that were not conclusive in this study.Keywords: Climate change, moving averages, climatology.

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Object-based vs. per-pixel classification of aster imagery for land cover mapping in semi-arid areas

10.1117/12.898317 ◽

2011 ◽

Author(s):

Mustafa M. El Abbas ◽

E. Csaplovics

Keyword(s):

Land Cover ◽

Land Cover Mapping ◽

Arid Areas ◽

Pixel Classification ◽

Object Based ◽

Semi Arid

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THE CLASSIFICATION OF LAND ACCORDING TO THE DEGREE OF RABBIT INFESTATION IN CENTRAL OTAGO

Proceedings of the New Zealand Grassland Association ◽

10.33584/jnzg.1987.48.1792 ◽

1987 ◽

pp. 65-70

Author(s):

I.G.C. Kerr ◽

J.M. Williams ◽

W.D. Ross ◽

J.M. Pollard

Keyword(s):

Carrying Capacity ◽

Mediterranean Climate ◽

Natural Habitat ◽

Public Funding ◽

Soil Survey ◽

European Rabbit ◽

Cultural Modification ◽

Classification Information ◽

Semi Arid

The European rabbit (Oryctolagus cuniculus) introduced into New Zealand in the 183Os, has consistently flourished in Central Otago, the upper Waitaki, and inland Marlborough, all areas of mediterranean climate. It has proved difficult to manage in these habitats. The 'rabbit problem' is largely confined to 105,000 ha of low producing land mostly in semi arid areas of Central Otago. No field scale modifications of the natural habitat have been successful in limiting rabbit numbers. The costs of control exceed the revenue from the land and continued public funding for control operations appears necessary. A system for classifying land according to the degree of rabbit proneness is described. Soil survey and land classification information for Central Otago is related to the distribution and density of rabbits. This intormation can be used as a basis for defining rabbit carrying capacity and consequent land use constraints and management needs. It is concluded that the natural rabbit carrying capacity of land can be defined by reference to soil survey information and cultural modification to the natural vegetation. Classification of land according to rabbit proneness is proposed as a means of identifying the need for, and allocation of, public funding tor rabbit management. Keywords: Rabbit habitat, rabbit proneness, use of rabbit prone land.

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