Abstract
Brazil contains the largest volume of freshwater of any nation in the world; however, this essential natural resource is threatened by rapid increases in water consumption and water quality degradation, mainly as a result of anthropogenic pressures. Declining water quality has become an increasingly more significant global concern as economic activities and human populations expand and climate change markedly alters hydrological cycles. Changes in land-use/land-cover (LULC) pattern have been recognized as a major driver of water quality degradation, however different LULC types and intensities affect water quality in different ways. In addition, the relationships between LULC and water quality may differ for different spatial and temporal scales. The increase in deforestation, agricultural expansion, and urban sprawl in Brazil highlights the need for water quality protection to ensure immediate human needs and to maintain the quality of water supplies in the long-term. Thus, this manuscript provides an overview of the relationships between LULC and water quality in Brazil, aiming at understanding the effects of different LULC types on water quality, how spatial and temporal scales contribute to these effects, and how such knowledge can improve watershed management and future projections. In general, agriculture and urban areas are the main LULCs responsible for water quality degradation in Brazil. However, although representing a small percentage of the territory, mining has a high impact on water quality. Water quality variables respond differently at different spatial scales, so spatial extent is an important aspect to be considered in studies and management. LULC impacts on water quality also vary seasonally and lag effects mean they take time to occur. Forest restoration can improve water quality and multicriteria evaluation has been applied to identify priority areas for forest restoration and conservation aiming at protecting water quality, but both need further exploration. Watershed modelling has been applied to simulate future impacts of LULC change on water quality, but data availability must be improved to increase the number, locations and duration of studies. Because of the international nature of watersheds and the consistent relationships between land use and water quality in Brazil, we believe our results will also aid water management in other countries.
| Original language | English |
|---|---|
| Article number | 110879 |
| Journal | Journal of Environmental Management |
| Volume | 270 |
| DOIs | |
| Publication status | Published - 15 Sept 2020 |
| Externally published | Yes |
Bibliographical note
Funding Information:We thank the National Institute for Space Research (INPE) for promoting the Brazilian Symposium on Remote Sensing, which gave us the opportunity to conduct a symposium about LULC and water quality, and the São Paulo Research Foundation ( FAPESP ) for supporting the speakers' participation. The insightful comments and suggestions of four anonymous reviewers greatly improved the paper.
Funding Information:
KM was funded by FAPESP grants 2013/0358-6 , 2014/19093-1 and 2017/24028-2 . RHT was funded by FAPESP grant 2 017/02455-6 and the National Council for Scientific and Technological Development ( CNPq grant 407502/2018-1 ). FRP was funded by FAPESP grant 2018/12341-0 . RAV was funded by FAPESP grant 2018/21612-8 . TOR was funded by the National Institute of Food and Agriculture ( CSREES , U.S. Department of Agriculture, Massachusetts Experiment Station, Project MAS00036 ). CGL was funded by FAPESP grant 2017/25383-0 . DRM was funded by Brazilian Electricity Regulatory Agency and Electric Power Company of Minas Gerais (CEMIG-P&D- ANEEL GT599). RMH was funded by Fulbright Brasil.
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© 2020 Elsevier Ltd
