Water infiltration in the domains of the Brazilian Tropical Savanna: what do we really know?

Abstract

Water infiltration is a key process in groundwater-river recharge. However, it is poorly known in the Brazilian Tropical Savanna (biome with different natural ecosystems, such as savannas, native grasslands, and forests). Thus, we carried out a review on soil water infiltration in different natural ecosystem types within the domains of the Brazilian Tropical Savanna. We collected articles from the Web of Science, Periódicos CAPES, and Scholar Google databases. We found 15 articles (including 22 assays) with studies prevailing in the Midwest region of Brazil. The mean and median infiltration capacity of all studies was 792 and 567 mm h-1, respectively. The majority of the studies (12 articles) did not clearly define which specific type of ecosystem was studied. Furthermore, most of the studies were carried out in Oxisols. Generally, the studies had a low sample size to characterize soil properties. A better description of ecosystem type, as well as a more significant sample size, are needed to understand infiltration in natural ecosystems of the Brazilian Tropical Savanna. Given the limitations of the studies available, our review showed that it is still too early to synthesize and to make an in-depth discussion on such topic in such huge and heterogeneous biome. Infiltração de água nos domínios da Savana Tropical Brasileira: o que realmente sabemos? R E S U M OA infiltração de água é um processo chave na recarga de rios e aquíferos. Entretanto, é pouco conhecido no Cerrado brasileiro (bioma com diferentes ecossistemas naturais, tais como as formações savânicas, campestres e florestais). Assim, realizou-se uma revisão sobre a infiltração de água no solo em diferentes tipos de ecossistemas dentro dos domínios do Cerrado brasileiro. Os artigos coletados foram das bases de dados Web of Science, Periódicos CAPES e Google escolar. Foram encontrados 15 artigos (que incluem 22 ensaios) presentes em sua maioria na região Centro-oeste do Brasil. A média e a mediana da capacidade de infiltração de todos os estudos foram 792 e 567 mm h-1, respectivamente. A maioria dos estudos (12 estudos) não define claramente qual o tipo de ecossistema foi avaliado. Além disso, a maioria dos estudos foram realizados em Latossolos. Em geral, os estudos tiveram um número amostral baixo para caracterizar as propriedades do solo. Diante disso, uma melhor descrição do tipo de ecossistema avaliado, bem como um número amostral mais significativo são necessários para compreender a infiltração de água nos ecossistemas naturais do Cerrado brasileiro. Em razão das limitações dos estudos encontrados, essa revisão mostrou que ainda é cedo para sintetizar e aprofundar a discussão deste tema em um bioma tão grande e heterogêneo.Palavras-chave: fitofisionomia, solo, vegetação nativa.

Effect of Prescribed Fire on Soil Permeability in a Neotropical Savanna

“…Prescribed re cause lower and even positive changes to soil properties compared to wild res, because they are low-intensity events that tend to be faster and are usually extinguished on the same day (Neto and Soares, 1995;Ferreira et al, 2010;Blum et al, 2011). Despite demonstrating the effects of prescribed re on soil physicochemical properties, such as increased pH and increased nutrient availability (K+, Ca2+, Mg2+, PO43-, NH4+), studies about the effects of prescribed re on soil physicochemical attributes are still incipient (Figueiredo et Analyzing the impacts that prescribed re can cause on soil physical properties will allow to understand the complex relationship of re, especially prescribed re, with soil physical-hydric attributes (hydrophobicity, in ltration and resistance to penetration) that still deserve attention (Brito et al, 2021, Lima 2021). The present study aimed to evaluate the effects of prescribed re on some soil physicalhydric properties -in ltration capacity, penetration resistance and hydrophobicity.…”