Assessment of water availability vulnerability in the Cerrado

Daniel Althoff,Demetrius David Da Silva,Lineu Neiva Rodrigues

doi:10.1007/s13201-021-01521-2

Daniel Althoff, Demetrius David Da Silva + Show 1 more

Open Access

https://doi.org/10.1007/s13201-021-01521-2

Copy DOI

Abstract

Many basins in the Cerrado biome already face increases in water disputes caused by agricultural expansion without long-term planning and monitoring of natural resources. The amount and timing of water availability are crucial for the socioeconomic development of agricultural activities and climate change resilience enhancement in the Cerrado. This study relied on a dataset developed for the Cerrado to characterize its climate and current water availability status. Different climate indices and hydrological signatures were adopted to describe the energy and water budget, climate seasonality, flow magnitude, flow dynamics, and average duration of low-flow events. Risk analysis was carried out to classify the monthly risk severity and identify periods and regions under a higher pressure regarding water availability in the Cerrado. Overall, the water availability is higher in the western and southern regions and lower in the eastern and northern regions, which experience a transition to a humid and semiarid climate, respectively. The water resources in the Cerrado occur under the highest pressure in September and October. We also identified regions with the potential to increase sustainable water use. These regions exhibit a low ratio between the flow equal to or exceeded 95% of the time and the mean flow (Q95/Q), which indicates that sustainable water use may be improved with techniques related to flow regularization and rainwater/runoff harvesting.

Highlights

The importance of the Cerrado biome has been recognized both as a biodiversity hotspot, with the richest flora among all of the savannas worldwide (Lambers et al 2020), and for its notable presence in the national economy (Lemes et al 2020)
The water availability is examined in terms of the water available from surface sources and largely characterized by hydrological signatures related to the flow distribution
Certain definitions of risk and water security have been applied to describe the potential to impose harmful states for humans or the environment (Hall and Borgomeo 2013), this study considered the risk as the susceptibility to low-flow conditions, which occurred because information concerning the water demand is scarce, and the hydrological signature (Q95) used as a reference to grant water permits is based on the flow distribution

Summary

Introduction

The importance of the Cerrado biome (the Brazilian tropical woodland savanna) has been recognized both as a biodiversity hotspot, with the richest flora among all of the savannas worldwide (Lambers et al 2020), and for its notable presence in the national economy (Lemes et al 2020). The agricultural success of this biome mainly stems from improvements in management practices and high technological and fertilization inputs (Hosono et al 2016; Lambers et al 2020). Another key factor responsible for the achieved agricultural success in the Cerrado is its climate. The Cerrado climate is mainly classified as a tropical savanna climate with dry winters (Alvares et al 2013) This climate is characterized by warm seasons with plentiful rainfall and sunlight to permit abundant plant growth. It is common for regions to benefit from a long wet season and the implementation of double cropping to increase profitability (Spangler et al 2017)

Objectives

Methods

Findings

Conclusion