How management alternatives of fast-growing forests affect water availability in southeastern Brazil: insights from a paired catchment experiment

Changes in land use and land cover (LULC) can result in significant changes in a hydrographic ba- sin flow regime. Future projections about LULC and its interference with water availability help to identify extreme events in advance and help propose appropriate management measures. Thus, this study aimed to make the LULC projection for the year 2030 for the Alto Rio Grande (ARG) sub- basin, located in Southeastern Brazil. This region was chosen because of its intense water resources use and for having recently faced water scarcity as result of prolonged droughts and inadequate water resources management. To identify the LULC trend for the year 2030, the Land Change Modeler (LCM) was used, the map obtained was inserted in the Soil and Water Assessment Tool (SWAT) model previously calibrated and validated for the region’ environmental and climatic conditions. The ARG sub-basin was affected by heavy rains in 2011, which resulted in changes in the landscape due to landslides. This particularity of the region contributed to the projection of LULC for the year 2030 to present an increase in forest and pastures to the agricultural areas detriment. When evaluating the impacts of these changes in water availability, it was observed that the SWAT model presented, for the same rainfall conditions, a reduction in peak streamflows of up to 59% and a reduction in the average monthly flow of up to 63% in 2030 in relation to the LULC observed in 2017. Thus, this study provides an important contribution by identifying a considerable reduction in water availability. These results will help to formulate strategies for water resources management and the adoption of measures to promote water security in the region.

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Colorful invasion in permissive Neotropical ecosystems: establishment of ornamental non-native poeciliids of the genera Poecilia/Xiphophorus (Cyprinodontiformes: Poeciliidae) and management alternatives

Neotropical Ichthyology ◽

10.1590/1982-0224-20160094 ◽

2017 ◽

Vol 15 (1) ◽

Cited By ~ 9

Author(s):

André Lincoln Barroso Magalhães ◽

Claudia Maria Jacobi

Keyword(s):

Native Species ◽

Poecilia Reticulata ◽

Southeastern Brazil ◽

Negative Effects ◽

Management Actions ◽

Xiphophorus Maculatus ◽

Xiphophorus Hellerii ◽

Gravid Females ◽

Poecilia Sphenops ◽

Management Alternatives

ABSTRACT Headwater creeks are environments susceptible to invasion by non-native fishes. We evaluated the reproduction of 22 populations of the non-native livebearers guppy Poecilia reticulata, black molly Poecilia sphenops, Yucatan molly Poecilia velifera, green swordtail Xiphophorus hellerii, southern platyfish Xiphophorus maculatus, and variable platyfish Xiphophorus variatus during an annual cycle in five headwater creeks located in the largest South American ornamental aquaculture center, Paraíba do Sul River basin, southeastern Brazil. With few exceptions, females of most species were found reproducing (stages 2, 3, 4) all year round in the creeks and gravid females of all species showed small sizes indicating stunting. Juveniles were frequent in all sites. The fecundity of the six poeciliids was always low in all periods. The sex ratio was biased for females in most species, both bimonthly as for the whole period. Water temperature, water level and rainfall were not significantly correlated with reproduction in any species. Therefore, most populations appeared well established. The pertinence of different management actions, such as devices to prevent fish escape, eradication with rotenone and research about negative effects on native species, is discussed in the light of current aquaculture practices in the region.

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Land-use influence on the soil hydrology: An approach in upper Grande River basin, Southeast Brazil

Ciência e Agrotecnologia ◽

10.1590/1413-7054201943015619 ◽

2019 ◽

Vol 43 ◽

Cited By ~ 2

Author(s):

Leandro Campos Pinto ◽

Carlos Rogério de Mello ◽

Lloyd Darrell Norton ◽

Nilton Curi

Keyword(s):

Land Use ◽

River Basin ◽

Water Availability ◽

Machine Learning Algorithms ◽

Southeastern Brazil ◽

Support Vector ◽

Native Forest ◽

Soil Hydrology ◽

Large Country ◽

Study Objective

ABSTRACT Brazil is a large country that depends on the hydroelectricity generation hydropower dams. The Upper Grande River Basin (UGRB) is one of the most important Brazilian hydrological regions in terms of water availability and electric energy production. Therefore, studies of water availability are indispensable for a better and more successful decision making in water resources management in the region. This study objective to approach the land-use influence on the soil hydrology in the Upper Grande River Basin, a strategic headwater basin of southeastern Brazil. This study uses hydrological indicators (baseflow/runoff (BF/R) and overland flow/runoff (OF/R)) extracted from eight watersheds, varying the size and localization in the region, to support the results found. Soil saturated hydraulic conductivity (Ko) was determined in situ using a constant flow permeameter, totaling 224 sampled points. Five machine learning algorithms were compared in their performance to predict Ko (Random Forest, Support Vector Machine, Gradient Boosting, Linear Regression, Regularization) using terrain attributes as covariates. The tested methods for predicting Ko resulted in a relatively low coefficient of determination (R2) due to the high spatial variability of this soil hydrologic attribute. The hydrological indicator BF/R was sensitive to land-use changes in the watersheds. The greatest Ko values were associated with native forest and the least values area associated with pasture and rupestrian field.

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Lonchocarpus cultratus (Vell.) A.V.G. Azevedo & H.C. Lima (Fabaceae) growth under different shade and water availability conditions

Revista CERES ◽

10.1590/0034-737x201865060004 ◽

2018 ◽

Vol 65 (6) ◽

pp. 491-499

Author(s):

Caroline Barbeiro ◽

Mariza Barion Romagnolo ◽

Lindamir Hernandez Pastorini

Keyword(s):

Water Availability ◽

Experimental Period ◽

Growth Characteristics ◽

Mycorrhizal Colonization ◽

Southeastern Brazil ◽

Initial Growth ◽

Plant Growth And Development ◽

Randomized Design ◽

Completely Randomized Design ◽

Etiolated Plants

ABSTRACT Light and water availability are among the environmental factors that most influence plant growth and development. The ability to acclimate to shade and tolerate drought can be assessed by growth characteristics. Thus, the objective of this study was to analyze the effect of water availability and shading on the initial growth of Lonchocarpus cultratus, a tree species, common name ‘embira-de-sapo’, abundant in several areas of South and Southeastern Brazil. The experiment was arranged in a 3x2 factorial completely randomized design. The plants were kept under 0%, 50%, and 80% shading and two conditions of water availability (daily irrigation - ID and twice a week - NDI). The variables height, root length, dry biomass of leaves, stem, and root were evaluated at 30, 60 and 90 days after emergence (DAE). Total, a, and b chlorophyll, mycorrhizal colonization, and nodulation were determined. Death of young plants maintained at 0% NDI occurred at the beginning of growth. At 90 DAE, plants kept under 80% shading and ID showed the highest height and etiolated plants due to the reduction of light intensity in this treatment. Over the experimental period, 0% and 50% shaded plants irrigated daily had the highest percentage of mycorrhizal colonization, and nodulation was observed in all plants regardless of the treatment.

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Estimating the impact of climate change on water levels in a data-poor river basin in southeastern Brazil

Water Policy ◽

10.2166/wp.2021.022 ◽

2021 ◽

Author(s):

Mateus Gonçalves Michelan ◽

Mateus Nardini Menegaz ◽

Flávio Aparecido Gonçalves ◽

Paulo Henrique Bretanha Junker Menezes ◽

Rafael de Oliveira Tiezzi

Keyword(s):

Climate Change ◽

Water Availability ◽

Climate Model ◽

Global Climate Models ◽

Water Levels ◽

Southeastern Brazil ◽

Climate Change Scenarios ◽

Hydrological Data ◽

Impact Of Climate Change ◽

The Impact

Abstract In basins with multiple water uses, it is possible a conflict over water use may occur. This probability increases under a water scarcity scenario. Therefore, it is important to estimate the possible impact of climate change on water availability in this type of basin, to support the decision-making of its users. The Ribeirão do Cipó is an example of a Brazilian watershed susceptible to this situation. Besides having poor hydrological data, it is used for public water supply, electricity generation and recreation. The present work developed a methodology for estimating water availability impacted by climate change, which was particularly applied to this watershed. The methodology consisted of feeding the rainfall–runoff hydrological model called soil moisture accounting procedure with precipitation and evapotranspiration data projected by the Eta-CPTEC regional climate model and nested to three global climate models. The outputs methods were obtained in terms of average monthly flow, for 2010–2039, 2040–2069 and 2070–2099 for the representative concentration pathway (RCP) 4.5 and RCP 8.5 scenarios. Despite the small amount of hydrological data available on the basin, the results were similar to those of the methods used as reference, thus demonstrating that the methodology used can be an alternative in estimating flow for climate change scenarios.

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