Soil maps, field knowledge, forest inventory and Ecological-Economic Zoning as a basis for agricultural suitability of lands in Minas Gerais elaborated in GIS

Abstract

Lands (broader concept than soils, including all elements of the environment: soils, geology, topography, climate, water resources, flora and fauna, and the effects of anthropogenic activities) of the state of Minas Gerais are in different soil, climate and socio-economics conditions and suitability for the production of agricultural goods is therefore distinct and mapping of agricultural suitability of the state lands is crucial for planning guided sustainability. Geoprocessing uses geographic information treatment techniques and GIS allows to evaluate geographic phenomena and their interrelationships using digital maps. To evaluate the agricultural suitability of state lands, we used soil maps, field knowledge, forest inventories and databases related to Ecological-Economic Zoning (EEZ) of Minas Gerais, to develop a map of land suitability in GIS. To do this, we have combined the maps of soil fertility, water stress, oxygen deficiency, vulnerability to erosion and impediments to mechanization. In terms of geographical expression, the main limiting factor of lands is soil fertility, followed by lack of water, impediments to mechanization and vulnerability to erosion. Regarding agricultural suitability, the group 2 (regular suitability for crops) is the most comprehensive, representing 45.13% of the state. For management levels A and B, low and moderate technological level, respectively, the most expressive suitability class is the regular, followed by the restricted class and last, the adequate class, while for the management level C (high technological level) the predominant class is the restricted. The predominant most intensive use type is for crops, whose area increases substantially with capital investment and technology (management levels B and C). Index terms:Geoprocessing, land suitable for agriculture, sustainability, multicriteria analysis. RESUMOAs terras (conceito mais abrangente do que solos, incluindo todos os elementos do ambiente: solos, geologia, relevo, clima, recursos hídricos, flora e fauna, além dos efeitos da ação antrópica) do estado de Minas Gerais estão em diferentes condições de solo, clima e sócio-economia, portanto, são distintas as vocações para produção de bens agrícolas e o mapeamento da vocação agrícola das terras do estado é fundamental para o planejamento norteado da sustentabilidade. O geoprocessamento utiliza técnicas de tratamento da informação geográfica e o SIG permite avaliar com mapas digitais os fenômenos geográficos e suas inter-relações. Objetivando avaliar a vocação agrícola das terras do estado, utilizaram-se o mapa de solos, o conhecimento de campo, o inventário florestal e o banco de dados relacionados ao Zoneamento Ecológico-Econômico (ZEE) de Minas Gerais, para elaborar em SIG o mapa de aptidão agrícola. Para tal, combinaram-se os mapas de fertilidade do solo, deficiência de água, deficiência de oxigênio, vulnerabilidade à erosão e de impedimentos à mecanização. Em termos de expressão geográfica, o principal fator limitante das terras é a fertilidade do ...

Vazões mínimas e de referência e rendimento específico para o estado de Minas Gerais

“…Já em estudo da aptidão agrícola das terras em Minas Gerais elaborada em Sistema de Informações Geográficas (SIG), Silva et al (2013) citam que as limitações por deficiência hídrica no Estado são principalmente moderadas, no entanto, no Norte do Estado as terras estão com deficiência hídrica com grau forte, relacionado com a ocorrência de regime climático do semiárido.…”

Mapping land use capability in tropical conditions adapting criteria to different levels of agricultural management

“…The water regime criterion was inferred from the vegetation phase: a) small valleys with distinctive hydrophytic vegetation, hygrophilous and hydrophilous grasslands -aquic water regime; b) perennial tropical forest -perudic water regime; c) semiperennial tropical forest and dystrophic facies cerradão (Portuguese augmentative of Cerrado) -udic water regime; d) semideciduous tropical forest, cerrado (neotropical savanna) and open cerrado -ustic water regime; e) deciduous tropical forest and grasslands -perustic water regime; f) hypo-xerophytic and hyper-xerophytic deciduous vegetation -aridic water regime. The shapefile of the soil map codified for the vegetation phase (Silva et al, 2013) was used as a reference in those soil mapping units without mention of this criterion. In some soil mapping units with simultaneous occurrence in both the north and the south of Minas Gerais, the legend indicates the existence of hypoxerophytic deciduous vegetation.…”

“…In the present study, we used: the soil map of Minas Gerais (UFV, CETEC, UFLA, FEAM, 2010) and a digital elevation model (DEM) of 90 m of spatial resolution extracted from the SRTM (Shuttle Radar Topographic Mission -NASA). They are the same that Silva et al (2013) used to map the agricultural suitability of the Minas Gerais state. First, the "slope" tool of ArcMap ® 10.3 was used to create the slope map from the DEM.…”