Global climate predictions and possible environmental impacts have an increasing source of concern in recent years. Analyses of the impacts of climate change scenarios on regional hydrology are ...required to design effective adaptation strategies for specific river basins. This study focuses on assessment of future climate change impacts on water resources of the Mundaú River Basin (MRB), in Brazil, using the Soil Water Assessment Tool (SWAT) and Regional Climate Models (RCMs) Eta‐MIROC5 and Eta‐HadGEM2, for three time periods under two Representative Concentration Pathways (RCPs). In general, climate models predict that the MRB will experience significant annual precipitation decreases, between 0.4% (1,087.45 mm) and 25.3% (815.59 mm), in both scenarios (RCP 4.5 and RCP 8.5) respectively, when compared to the observed period (2003–2016). Maximum and minimum temperature increases up to 2.3°C and 0.65°C under the RCP 4.5 scenario, and up to 4.3°C and 2.2°C under the RCP 8.5 scenario. SWAT simulations predict substantial surface runoff decreases with a minimum average annual value of 21.3 mm for the RCP 8.5 in medium‐term. Additionally, actual evapotranspiration (ET) is predicted to decrease from 780.77 to a minimum of 648.1 mm, although increases in potential evapotranspiration (ET0) are expected. In general, annual streamflow also is expected to decrease, more severely under RCP 8.5 conditions, reaching a drop of approximately 66.7% (15.2 m3·s−1), compared to the observed period (45.5 m3·s−1). Seasonal streamflow is predicted to decrease for both models, in both rainy and dry seasons, except for medium‐term of the Eta‐HadGEM2. Although there are still some uncertainties associated with climate models, the findings from this study can assist water resource managers in management decisions for appropriate water use, development of public policies that favour sustainability, and adoption of mitigation and prevention practices to ensure water security in the basin.
In the future, reductions in rainfall and increases in temperatures are expected for the MRB for most of three time periods analysed under both models and RCP scenarios.
The projections of the Eta‐MIROC5 indicated that the MRB will become warmer and drier, possibly causing water shortages throughout the basin.
The projections of Eta‐HadGEM2 diverged from the Eta‐MIROC5 forecasts in the medium term.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Water stress on crops can severely disrupt crop growth and reduce yields, requiring the accurate and prompt diagnosis of crop water stress, especially in semiarid regions. Infrared thermal imaging ...cameras are effective tools to monitor the spatial distribution of canopy temperature (Tc), which is the basis of the daily water stress index (DWSI) calculation. This research aimed to evaluate the variability of plant water stress under different soil cover conditions through geostatistical techniques, using detailed thermographic images of Neem canopies in the Brazilian northeastern semiarid region. Two experimental plots were established with Neem cropped under mulch and bare soil conditions. Thermal images of the leaves were taken with a portable thermographic camera and processed using Python language and the OpenCV database. The application of the geostatistical technique enabled stress indicator mapping at the leaf scale, with the spherical and exponential models providing the best fit for both soil cover conditions. The results showed that the highest levels of water stress were observed during the months with the highest air temperatures and no rainfall, especially at the apex of the leaf and close to the central veins, due to a negative water balance. Even under extreme drought conditions, mulching reduced Neem physiological water stress, leading to lower plant water stress, associated with a higher soil moisture content and a negative skewness of temperature distribution. Regarding the mapping of the stress index, the sequential Gaussian simulation method reduced the temperature uncertainty and the variation on the leaf surface. Our findings highlight that mapping the Water Stress Index offers a robust framework to precisely detect stress for agricultural management, as well as soil cover management in semiarid regions. These findings underscore the impact of meteorological and planting conditions on leaf temperature and baseline water stress, which can be valuable for regional water resource managers in diagnosing crop water status more accurately.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Hydrological studies in small basins are essential for
investigating the role of distinct processes on water resources conservation
and to assess the impact of the natural ecosystems on improving ...water
security especially in semiarid environments. In Brazil, the cooperative
hydrological Network REHISA (“REde de HIdrologia do SemiÁrido”)
comprises hydrologists from several universities of Brazil, focusing on
field measurements, monitoring and modeling activities in well instrumented
experimental rural catchments located at different regions and biomes in
Semiarid environment. Water scarcity is a common aspect among the
catchments, as well as risks of soil and water degradation. The objective of
this work is to present assessments of near surface soil moisture
spatial-temporal distribution, and to evaluate the impact of soil
conservation techniques in reducing runoff, using small-scale experimental
plots in a representative catchment of the Pernambuco State, Brazil. The
study catchment is located in Alto Ipanema River Basin (AIRB) (with an area
of 150 km2), which is located at the semiarid region of the São
Francisco River (area of 641 000 km2). Soil and water monitoring was
performed in experimental plots with different soil cover conditions (Bare
soil plots; Plots with natural cover – Caatinga Biome vegetation; Plots with
cactus Palma barriers; and Plots with mulch cover – Dry grass mulch at 4 t ha−1), where probes were installed for high resolution soil moisture
assessment. In addition, regular soil moisture monitoring campaigns were
conducted at 7 different locations, using a capacitance probe, with arboreal
and shrub Caatinga vegetation, pasture and bare soil, predominantly
Brachiaria decumbens. Mulch cover runs close to the Caatinga cover, but
still with higher runoff generation, and presenting lower soil moisture
temporal mean values. Caatinga was highly effective in terms of soil and
water conservation at the small basin scale for both the dry and the wet
season, resulting in a positive nexus between vegetation and water
availability at the region.
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•Remotely sensed data are integrated with a GIS water balance approach.•The spatial-temporal distribution of groundwater recharge is estimated in semi-arid regions.•The WTF method is ...used to evaluate groundwater estimations from remotely sensed data.•The remote sensing data provide good estimates of groundwater recharge.
Data limitations on groundwater (GW) recharge over large areas are still a challenge for efficient water resource management, especially in semi-arid regions. Thus, this study seeks to integrate hydrological cycle variables from satellite imagery to estimate the spatial distribution of GW recharge in the Ipanema river basin (IRB), which is located in the State of Pernambuco in Northeast Brazil. Remote sensing data, including monthly maps (2011–2012) of rainfall, runoff and evapotranspiration, are used as input for the water balance method within Geographic Information Systems (GIS). Rainfall data are derived from the TRMM Multi-satellite Precipitation Analysis (TMPA) Version 7 (3B43V7) product and present the same monthly average temporal distributions from 15 rain gauges that are distributed over the study area (r=0.93 and MAE=12.7mm), with annual average estimates of 894.3 (2011) and 300.7mm (2012). The runoff from the Natural Resources Conservation Service (NRCS) method, which is based on regional soil information and Thematic Mapper (TM) sensor image, represents 29% of the TMPA rainfall that was observed across two years of study. Actual evapotranspiration data, which were provided by the SEBAL application of MODIS images, present annual averages of 1213 (2011) and 1067 (2012)mm. The water balance results reveal a large inter-annual difference in the IRB GW recharge, which is characterized by different rainfall regimes, with averages of 30.4 (2011) and 4.7 (2012)mmyear−1. These recharges were mainly observed between January and July in regions with alluvial sediments and highly permeable soils. The GW recharge approach with remote sensing is compared to the WTF (Water Table Fluctuation) method, which is used in an area of alluvium in the IRB. The estimates from these two methods exhibit reliable annual agreement, with average values of 154.6 (WTF) and 124.6 (water balance) mm in 2011. These values correspond to 14.89 and 13.53% of the rainfall that was recorded at the rain gauges and the TMPA, respectively. Only the WTF method indicates a very low recharge of 15.9mm for the second year. The values in this paper provide reliable insight regarding the use of remotely sensed data to evaluate the rates of alluvial GW recharge in regions where the potential runoff cannot be disregarded from WB equation and must be calculated spatially.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Type 1 diabetes mellitus (DM1) is one of the most common chronic diseases observed during childhood. The incidence of DM1 is increasing worldwide, and there is currently no way to prevent or delay ...the onset or to cure the disease. Most diseases, including diabetes, stem from abnormalities in the functioning of proteins, and some studies have reported the expression of protein variation to be involved in the development of DM1. Thus, the aim of this study was to investigate the differential expression of serum proteins in patients with DM1.
Serum of patients with DM1 (n=30) and healthy controls (n=30) was collected. A proteomic approach was used with depletion of albumin and immunoglobulin G chromatography on serum samples followed by data-independent, label-free mass spectrometric analysis.
A total of eight serum proteins were identified as being differentially expressed and involved in the immune system, lipid metabolism, and pathways of coagulation. DM1 was associated with the upregulation of six proteins: alpha-2-macroglobulin, apolipoprotein A-II, β2 glycoprotein I, Ig alpha-2 chain C region, alpha-1-microglobulin, and prothrombin. A total of two proteins were downregulated, including pregnancy zone protein and complement C4.
To the best of our knowledge, these findings show differential expression of proteins revealing new proteins that may be involved in the development and progression of diabetes.
Water scarcity and changing rainfall distribution have caused uncertainties in relation to agricultural production in semiarid areas. In this context, water reuse for irrigation is a promising ...alternative, although requiring irrigation and agricultural management. Production of forage plants is strategic for semiarid areas due to their high tolerance to stresses and use as animal fodder. The objective of this work was to evaluate the combined performance of treated wastewater irrigation and mulching on forage sorghum and on soil attributes in Northeast Brazil. Sorghum was cropped in November 2018, three months before the beginning of the hydrologic year, and cultivated over three cycles until April 2019. The experiment was designed with five irrigation depths (60%, 80%, 100%, 120%, and 140% of crop evapotranspiration), and with four soil cover conditions (0% (witness), soil covered with native vegetation, with coconut coir, and with macerated moringa seeds), adopting four replications. Irrigation with treated wastewater promoted linear increases in forage sorghum yield at irrigation depths of up to 140% of crop evapotranspiration. Mulch promoted a 24% increase in productivity in relation to the area where conservation was not practiced, being able to control salinity while also contributing to the higher incorporation of organic matter. Irrigation with treated wastewater had no negative agronomic impacts on soil, once natural rainfall events typical of the Brazilian semiarid region allowed effective salt leaching from shallow sandy soils.
This paper presents a two-dimensional (2D) numerical model of soil erosion and sediment transport resulting from rainfall induced overland flow. It is a spatial and temporal dynamic model combining ...physical and empirical laws and comprises: i) An overland flow module that solves the two-dimensional unsteady water flow equations on an infiltrating surface; ii) A soil infiltration module that uses a combined Horton-SCS scheme; and iii) A soil erosion and sediment transport module that solves the two-dimensional sediment transport equation, distinguishing between rill erosion, interrill erosion and sediment deposition.
The performance of the model was evaluated by comparing its results with observed data from laboratory rainfall-runoff experiments on a two-directional 2.00 × 2.00 m
soil flume set at 1% and 10% slopes in the x- and y-directions, respectively. The x-direction produced remarkably lower runoff and transported sediments than the y-direction. The numerical model significantly underestimated x-direction lower values of runoff and transported sediments. However, in the y-direction the model presented very good performance. Overall, in total terms (x- plus y-direction), the numerically simulated graphs of runoff and sediment transport were in very good agreement with corresponding experimental measurements, demonstrating the laboratory proof-of-concept of the model.
Understanding small-scale hydrologic processes and the impact of soil conservation techniques are crucial in reducing runoff and sediment losses in semi-arid regions. This study was conducted in the ...Alto Ipanema River Basin, in Pernambuco State (Brazil). Soil and water dynamics were intensely monitored in twelve experimental plots with different coverage conditions (plot with bare soil—Bare; plot with natural vegetation—Natur; plot with mulch—Mulch; plot with Cactus Palma—Palma). By far, bare soil conditions produced higher runoff and soil losses. Mulch cover was close to natural vegetation cover, but still presented higher runoff and sediment losses. Palma, which is a very popular spineless cactus for animal feed in the Brazilian semi-arid region, presented an intermediate hydrologic impact in controlling runoff, enhancing soil moisture, and also reducing soil losses. Experiments were conducted in one hydrologic year (2016/2017) at three different sites. They were intensely monitored and had the same number of plots. This enabled us to carry out a robust performance assessment of the two soil conservation practices adopted (Mulch and Palma), compared to natural vegetation cover and bare soil conditions. Such low-cost alternatives could be easily adopted by local farms in the region, and, hence, improve soil reclamation and regional resiliency in a water-scarce environment.
Macropores and water flow in soils and substrates are complex and are related to topics like preferential flow, nonequilibrium flow, and dual-continuum. Hence, the quantification of the number of ...macropores and the determination of their geometry are expected to provide a better understanding on the effects of pores on the soil’s physical and hydraulic properties. This exploratory study aimed at evaluating the potential of using infrared thermography for mapping macroporosity at the soil surface and estimating the number and size of such macropores. The presented technique was applied to a small scale study (laboratory soil flume).
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
ABSTRACT The application of chemical substances to the soil together with little attention given to the possible environmental impacts, transformed the environment into a recipient of waste. The aim ...of this study was to simulate the movement of water and solutes (sodium and potassium together) using the STANMOD and HYDRUS-2D models in a typical Haplic Planosol under the application of wastewater via surface irrigation under different flow rates. The experiment was conducted in the laboratory by miscible displacement tests, first using columns with deformed soil under saturation and steady water flow conditions, at a rate of 11.7 cm3 min-1, to obtain transport parameters of sodium and potassium ions, and in the applied residual water, the values of 475 and 76.6 mg dm-3, respectively. The transport parameters were estimated from the numerical adjustment of effluent distribution curves, using the STANMOD model. In a second step, the HYDRUS-2D model was applied to simulate the volumetric soil moisture distribution profiles, as well as the ion concentrations in the wet bulb. Considering the results obtained, we can see that there was considerable interaction between the solutes and the soil. The value of the delay parameter was higher for the sodium when compared to the potassium, reflecting its greater adsorption and the processes of exchange between the solute and the soil. The results suggested the need for adequate soil management in order to avoid future soil sodification and, in view of the application of HYDRUS-2D, it was verified that the model presented a satisfactory performance in the simulation of the displacement of the ions, after 1, 5 and 10 hours of wastewater application.
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