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Alfalfa (Medicago sativa L.) grassland is prone to degradation following multi-year maintenance. Yet, its mechanism regarding the stoichiometry of carbon (C) and nitrogen (N) across plant-soil system is still unclear. To address this issue, the method of space-for-time sampling was employed to investigate alfalfa grasslands with five planting years (5-, 8-, 10-, 15-, and 20-year periods) in the semiarid Loess Plateau. The results showed that the alfalfa above- and underground biomass decreased steadily decrease after the fifth to eighth years, showing a degradation tendency with the extension of planting duration. The mean weight diameter of aggregate registered an increase with planting years. However, the C and N stocks decreased with planting years in five soil aggregate fractions. Specifically, they were the highest in the fifth year and then started to gradually decrease along the 8th, 10th, 15th, and 20th year. Redundancy and correlation analysis confirmed that the C and N stocks of soil aggregates were closely positively associated with those of plant. Overall, the highest stability of soil physical structure was found during the period from the fifth to eighth year, and, afterward, the stability declined. In conclusion, alfalfa plantation improved soil structure stability but aggravated soil C and N stocks, and biomass and soil aggregate indicators accounted for alfalfa field degradation after a certain year of plantation. [ABSTRACT FROM AUTHOR]

Introduction: Long-term application of excessive nitrogen (N) not only leads to low N use efficiency (NUE) but also exacerbates the risk of environmental pollution due to N losses. Substituting partial chemical N with organic fertilizer (SP) is an environmentally friendly and sustainable fertilization practice. However, the appropriate rate of SP in rainfed maize cropping systems in semi-arid regions of China is unknown. Methods: Therefore, we conducted a field experiment between 2021 and 2022 in a semi-arid region of Northern China to investigate the effects of SP on maize growth, carbon and N metabolism (C/NM), and NUE. The following treatments were used in the experiment: no N application (CK), 100% chemical N (SP0, 210 kg N ha-1), and SP substituting 15% (SP1), 30% (SP2), 45% (SP3), and 60% (SP4) of the chemical N. The relationship between these indicators and grain yield (GY) was explored using the Mantel test and structural equation modeling (SEM). Results and discussion: The results found that the SP1 and SP2 treatments improved the assimilates production capacity of the canopy by increasing the leaf area index, total chlorophyll content, and net photosynthetic rate, improving dry matter accumulation (DMA) by 6.2%-10.6%, compared to the SP0 treatment. SP1 and SP2 treatments increased total soluble sugars, starch, free amino acids, and soluble protein contents in ear leaves via increasing the enzymatic reactions related to C/NM in ear leaves during the reproductive growth stage compared with SP0 treatment. The highest plant nitrogen uptake (PNU) and nitrogen recovery efficiency were obtained under the SP2 treatment, and the GY and nitrogen agronomic efficiency were higher than the SP0 treatment by 9.2% and 27.8%. However, SP3 and SP4 treatments reduced DMA and GY by inhibiting C/NM in ear leaves compared to SP0 treatment. Mantel test and SEM results revealed that SP treatments indirectly increased GY and PNU by directly positively regulating C/NM in maize ear leaves. Therefore, in the semi-arid regions, substituting 30% of the chemical N with SP could be considered. This fertilizer regime may avoid GY reduction and improve NUE. This study provides new insights into sustainable cultivation pathways for maize in semi-arid regions. [ABSTRACT FROM AUTHOR]

Xerophytic vegetation re-regulates and allocates water resources through canopy interception, root water uptake and transpiration, and changes the water budget among precipitation, runoff, interception and infiltration, thus having a significant impact on the processes of the hydrological cycle. In this study, we investigated the effect of xerophytic shrub-Salix on soil water redistribution and water budget through an in situ monitoring experiment combined with two-dimensional vegetation water consumption modeling. The results showed that, due to the interception effect of root water uptake, it was difficult for precipitation infiltration to recharge deep soil water and groundwater. The measured data of soil moisture content, hydraulic head and precipitation were used to verify and calibrate the performance of the soil water flow model in the vadose zone by HYDRUS-2D. The effect of roots system on soil water was simulated, and the appropriate spacing of Salix replanting was estimated. Combined with the relationship between the transverse roots system and the crown width obtained by the investigation, it was determined that the spacing between the Salix should be greater than five times the crown width, so that the balance between the water consumption of Salix and the water supply of deep soil by precipitation could be considered. The results of this study are important for estimating groundwater recharge in arid areas and provide practical vegetation replanting options for similar regions. [ABSTRACT FROM AUTHOR]

Crossbreeding is a well-established practice in livestock production aimed at improving reproductive and productive traits. This study evaluated the effects of crossbreeding on rabbits, focusing on comparisons between purebred Flemish Giant (n = 10), New Zealand White (n = 23), and their crossbred offspring (n = 27). Various parameters, including litter size, body weight, growth rate, and mortality, were assessed. The results demonstrated that crossbred rabbits presented a 15% faster growth rate than purebred rabbits, along with the lowest mortality rate and highest total meat output. This phenomenon, attributed to hybrid vigour, effectively blends the large frame of the Flemish Giant with the good litter size of the New Zealand White. Furthermore, statistical analyses, including ANOVA and Tukey‒Kramer’s honestly significant test, confirmed the significant effects of breed class on productivity, body weight, and carcass yield. Growth curves estimated using the Gompertz model highlighted the superior performance of crossbred rabbits under semiarid conditions. Notably, crossbreeding resulted in offspring with the highest dressing percentage and overall improved performance, offering potential advantages for rabbit producers worldwide. [ABSTRACT FROM AUTHOR]

The Google Earth Engine (GEE) was used to investigate the performance of the Global Land Data Assimilation System (GLDAS) soil temperature (ST) data against observed ST from 13 synoptic stations over a semiarid region in Iran. Three‐hourly ST data were collected and analyzed in two depths (0–10 cm; 40–100 cm) and 5 years. In each depth, GLDAS‐Noah ST data were evaluated for daily minimum, maximum, and average ST (i.e., Tmin, Tmax, and Tavg). Based on the correlation coefficient, Kling–Gupta Efficiency, and Nash–Sutcliffe Efficiency the overall performance of the GLDAS‐Noah is 0.96, 0.66, and 0.79 for Tmin; 0.97, 0.84, and 0.89 for Tavg; and 0.95, 0.89, and 0.89 for Tmax, respectively in the first layer. Likewise, 0.97, 0.85, and 0.86 for Tmin; 0.97, 0.77, and 0.80 for Tavg; and 0.97, 0.69, and 0.69 for Tmax are obtained in the second layer. However, there is a significant negative bias which tends to underestimate ST in the two investigated layers, given by an average bias over all the stations analyzed of −24%, −12%, and −5% for Tmin, Tavg, and Tmax in the first layer, and average bias of −8%, −13%, and −17% for Tmin, Tavg, and Tmax in the second layer. This study reveals that GLDAS‐Noah‐derived ST can be used in arid regions where little or no observation data is available. Moreover, GEE performed as an advanced geospatial processing tool in regional scale analysis of ST in different layers. [ABSTRACT FROM AUTHOR]

ABSTRACT: The aim of this study was to determine the occurrence of infection by Ehrlichia canis, Anaplasma platys, Babesia vogeli, and Hepatozoon canis in dogs from the semiarid region of Rio Grande do Norte state. Also, we evaluated the characteristics that favor the infection by E. canis and the presence of Rhipicephalus sanguineus s.l. ticks. For that, 120 dogs were included, from which blood samples were collected for DNA extraction and molecular diagnosis of these four pathogens. Anamnesis and physical examination were performed on each patient, and all properties were characterized. Chi-square and Fisher’s exact tests were used to verify the association of the studied variables. The most prevalent pathogen in the study was E. canis (13.3%), followed by A. platys (11.7%), H. canis (6%) and B. vogeli (6%). Correspondence analysis performed between E. canis positivity and the variables studied showed the influence of factors such as tick history, non-vaccination and non-use of antiparasitic medications. The main environmental factor observed in the infection by E. canis was the presence of trees and vegetation in the residences. Recognizing these characteristics can help elaborate prevention and control strategies since environmental management activities seek to reduce the interaction between vector and host and, consequently, the exposure to diseases.

The semiarid region of Pernambuco produces 99.5% of the forage corn, considering that 93.8% of the ruminant herd is produced in this region of the Brazilian Northeast. The Agreste Meridional is located in this region, which presents seasonality in production due to water deficit. Silage is one of the adopted roughage conservation strategies, with corn being the forage that presents the best indicators when fed to animals. Agronomic aspects are often neglected, considering that the performance of cultivars may vary with the growing environment. The objective of this research was the introduction and evaluation of corn cultivars for the production for whole-plant silage in the Agreste Meridional of Pernambuco, Brazil. The experiment was carried out in a randomized block design, with seven treatments, of which five non transgenic cultivars (‘Alagoano’, ‘Nordestino’, ‘São Luís’, ‘PV2 Viçosense’ and ‘PV1 Branca’) and two transgenic hybrids (‘LG 6030 VT PRO2’ and ‘AS 1573 YG’). It was observed that all genotypes showed susceptibility to Spodoptera frugiperda and Helicoverpa zea, except for the ‘AS 1573 YG’ hybrid, due to the Bt technology. The biometric characters of the genotypes were influenced by the environment. However, with yield of 10,537 and 10,666 kg ha-1 (dry matter), the genotypes ‘Alagoano’ and ‘AS 1573 YG’, respectively, were selected for cultivation in the Agreste Meridional region for the production of silage, which can be used in intensive production systems or family farming.

The semiarid region of Pernambuco produces 99.5% of the forage corn, considering that 93.8% of the ruminant herd is produced in this region of the Brazilian Northeast. The Agreste Meridional is located in this region, which presents seasonality in production due to water deficit. Silage is one of the adopted roughage conservation strategies, with corn being the forage that presents the best indicators when fed to animals. Agronomic aspects are often neglected, considering that the performance of cultivars may vary with the growing environment. The objective of this research was the introduction and evaluation of corn cultivars for the production for whole-plant silage in the Agreste Meridional of Pernambuco, Brazil. The experiment was carried out in a randomized block design, with seven treatments, of which five non transgenic cultivars (‘Alagoano’, ‘Nordestino’, ‘São Luís’, ‘PV2 Viçosense’ and ‘PV1 Branca’) and two transgenic hybrids (‘LG 6030 VT PRO2’ and ‘AS 1573 YG’). It was observed that all genotypes showed susceptibility to Spodoptera frugiperda and Helicoverpa zea, except for the ‘AS 1573 YG’ hybrid, due to the Bt technology. The biometric characters of the genotypes were influenced by the environment. However, with yield of 10,537 and 10,666 kg ha-1 (dry matter), the genotypes ‘Alagoano’ and ‘AS 1573 YG’, respectively, were selected for cultivation in the Agreste Meridional region for the production of silage, which can be used in intensive production systems or family farming. [ABSTRACT FROM AUTHOR]

The aim of this article is to identify, based on a literature review, the most suitable water treatment technologies for the production of reuse water to be used by industries that are often present in the Brazilian semi-arid region. For this research, we selected studies on water treatment with low implementation costs and advanced development for implementation. This study identified water treatment technologies for the production of reuse water in the leather and footwear, textile, metallic and non-metallic mineral extraction and food and beverage industries. The search was carried out in the scientific databases Scopus and Web of Science, with no restrictions on the year of publication. Based on the selected articles, a summary was made of the most suitable water treatment systems for each industrial sector, providing an overview of the treatments recommended for water-scarce regions. Water reuse can be implemented in various industrial activities, including the use of boilers, cooling towers, toilet flushing, local irrigation and reintroduction into the process as a by-product. There are various methods of water treatment, although it is necessary to assess which is most suitable for each type of industry. Aspects such as the amount of effluent generated, the necessary properties of the water to be reused and the cost of the project must be carefully evaluated if the benefits are to be achieved. [ABSTRACT FROM AUTHOR]

Abstract The Google Earth Engine (GEE) was used to investigate the performance of the Global Land Data Assimilation System (GLDAS) soil temperature (ST) data against observed ST from 13 synoptic stations over a semiarid region in Iran. Three‐hourly ST data were collected and analyzed in two depths (0–10 cm; 40–100 cm) and 5 years. In each depth, GLDAS‐Noah ST data were evaluated for daily minimum, maximum, and average ST (i.e., Tmin, Tmax, and Tavg). Based on the correlation coefficient, Kling–Gupta Efficiency, and Nash–Sutcliffe Efficiency the overall performance of the GLDAS‐Noah is 0.96, 0.66, and 0.79 for Tmin; 0.97, 0.84, and 0.89 for Tavg; and 0.95, 0.89, and 0.89 for Tmax, respectively in the first layer. Likewise, 0.97, 0.85, and 0.86 for Tmin; 0.97, 0.77, and 0.80 for Tavg; and 0.97, 0.69, and 0.69 for Tmax are obtained in the second layer. However, there is a significant negative bias which tends to underestimate ST in the two investigated layers, given by an average bias over all the stations analyzed of −24%, −12%, and −5% for Tmin, Tavg, and Tmax in the first layer, and average bias of −8%, −13%, and −17% for Tmin, Tavg, and Tmax in the second layer. This study reveals that GLDAS‐Noah‐derived ST can be used in arid regions where little or no observation data is available. Moreover, GEE performed as an advanced geospatial processing tool in regional scale analysis of ST in different layers.

Xerophytic vegetation re-regulates and allocates water resources through canopy interception, root water uptake and transpiration, and changes the water budget among precipitation, runoff, interception and infiltration, thus having a significant impact on the processes of the hydrological cycle. In this study, we investigated the effect of xerophytic shrub-Salix on soil water redistribution and water budget through an in situ monitoring experiment combined with two-dimensional vegetation water consumption modeling. The results showed that, due to the interception effect of root water uptake, it was difficult for precipitation infiltration to recharge deep soil water and groundwater. The measured data of soil moisture content, hydraulic head and precipitation were used to verify and calibrate the performance of the soil water flow model in the vadose zone by HYDRUS-2D. The effect of roots system on soil water was simulated, and the appropriate spacing of Salix replanting was estimated. Combined with the relationship between the transverse roots system and the crown width obtained by the investigation, it was determined that the spacing between the Salix should be greater than five times the crown width, so that the balance between the water consumption of Salix and the water supply of deep soil by precipitation could be considered. The results of this study are important for estimating groundwater recharge in arid areas and provide practical vegetation replanting options for similar regions.

Although nitrogen is the nutrient most required by maize, doses of N lower than those recommended are applied to maize grown in semiarid environments, which limits the achievement of profitable yields. The objective of this study was to evaluate changes in soil fertility, nutritional status and dry matter production of maize plants fertilized with organic and mineral fertilizers in a semiarid region. A factorial experiment was carried out in Sobral, Ceará state, Brazil, in a randomized block design. The factors were two N sources (organic compost and urea), and four N rates: 27.5, 55, 110 and 165 kg ha−1, with three replications. We assessed variables associated with soil fertility, plant nutritional status, chlorophyll content, grain yield and total dry matter production. The highest rates of organic compost resulted in the highest levels of P (17.7 mg dm−3) and K (102.2 mg dm−3) in soil when compared to the control (7.7 and 69.0 mg dm−3, respectively). However, organic compost rates below 110 kg ha−1 of N-equivalent fertilizer were not enough to supply the plants' demand for P and K. Low N rates promoted a decrease in soil inorganic N in the second year of application. Applying urea to maize plants led to greater dry matter production than organic compost in the second consecutive crop season. The use of organic compost at rates lower than 110 kg ha−1 of N-equivalent fertilizer decreases soil fertility and has no impact on maize dry matter production. [ABSTRACT FROM AUTHOR]

Carbon sequestration is the process of capturing, securing and storing carbon dioxide from the atmosphere. In this study, the carbon sequestration capacity of Hedera colchica was investigated in soil of a semiarid region in Iran. Samples were taken from plants cultivated in the semiarid area of the polluted metropolis of Tehran and the amount of sequestered carbon in the aboveground and underground parts of the plant was measured. The conversion coefficient of carbon sequestration of plant organs (stem, leaf, and root) was determined separately by the combustion method. Carbon tax policy was used to evaluate the carbon sequestration function, as the shadow price of carbon. The results showed a significant difference in the amount of carbon sequestration in different organs of the plant. Stems and roots with 29.3 and 4.3 t ha−1, respectively, showed the highest and lowest amount of carbon deposition. The results of the economic value showed that the carbon shadow price was $40567.6 ha−1 on average. In general, the results of this study showed that the organs of H. colchica can have a beneficial effect in the process of carbon sequestration. [ABSTRACT FROM AUTHOR]

Management practices might alter soil chemical properties. This study evaluated soil chemical properties in a forage cactus Opuntia stricta (Haw.) Haw. ('Orelha de Elefante Mexicana') (OEM) production system in the Brazilian semiarid region. The experiment was established in June 2011, and the design was a split-split-plot in randomized complete blocks, in which the main plots were formed by distinct levels of organic fertilizer (cattle manure) (0, 10, 20, and 30 Mg ha−1 year−1), the subplots were formed by different levels of N inorganic fertilizer applied as urea (0, 120, 240, and 360 kg N ha−1 year−1), and the sub-subplots were distinguished by the distinct OEM harvesting frequency (annual or biennial). Soil samples were collected for chemical analysis, C and N contents analysis, and stocks analysis at 0 to 10 and 10 to 20 cm depths in August 2019. Organic fertilizer contributed to a linear increase in soil pH, Ca2+, Na+, sum of bases (SB), cation exchange capacity (CEC), and base saturation (V) at both depths (p < 0.05). With the application of 30 Mg ha−1 year−1 of cattle manure, there was storage of approximately 126 Mg C ha−1 and 13 Mg N ha−1 at 0 to 20 cm depths. Managing OEM with organic fertilizer and a biennial frequency of harvesting affects the soil's chemical characteristics in cactus orchards, and it is a sustainable alternative for semiarid regions. [ABSTRACT FROM AUTHOR]

In the face of urban expansion, ensuring sustainable water consumption is paramount. This study aims to develop a domestic water demand forecast model that considers population heterogeneity and the urban area distribution in a city in the Brazilian Semiarid Region. The methodology comprises three main steps: (1) spatial data collection to identify explanatory variables for a future Land Use and Cover (LULC) model; (2) simulation of LULC data for 2030, 2040, and 2050 using the MOLUSCE plugin; and (3) estimation of domestic water demand based on projected urban area expansion and a linear regression model incorporating demographic indicators of household income, residents per household, total population, and gender. The results demonstrated a consistent LULC simulation, indicating an urban expansion of 4 km2 between 2030 and 2050, with reductions of 0.6 km2 in natural formations and 3.4 km2 in farming areas. Using LULC data, the study predicted a 14.21% increase in domestic water consumption in Campina Grande for 2050 compared to 2010, equivalent to an increase of 2,348,424.96 m3. Furthermore, the spatial analysis draws a spatial profile of water consumption among residents, highlighting the areas with the highest per capita consumption. Thus, this research offers a consistent approach to estimating water demand in regions with limited consumption data, providing valuable insights for decision-makers to consider in urban planning. [ABSTRACT FROM AUTHOR]

This article presents a study on the spatiotemporal dynamics of land cover and use, vegetation indices, and water content in the semiarid region of Pernambuco, Brazil. This study is based on an analysis of satellite images from the years 2016, 2018, and 2019 using the MapBiomas platform. The results show changes in the predominant land cover classes over time, with an increase in the caatinga area and a decrease in the pasture area. An analysis of the vegetation indices (NDVI and LAI) indicated low vegetation cover and biomass in the study area, with a slight increase in the NDVI in 2018. An analysis of the Modified Normalized Difference Water Index (MNDWI) showed that the water content in the study area was generally low, with no significant variations over time. An increase in the water bodies, mainly due to the construction of a reservoir, was noted. The results of this study have provided important information for natural resource management in the region, including the development of strategies for the sustainable use and management of natural resources, particularly water resources, vegetation cover, and soil conservation.

Towards a better understanding of factors controlling carbon (C) exchange between inland waters and atmosphere, we addressed the inorganic carbon cycle in semiarid lakes of Central Eurasia, subjected to the strong impact of on-going climate change. As such, we assessed the hydrochemical variability and quantified its control on the formation of authigenic carbonate minerals, occurring within the upper layer of sediments in 43 semiarid lakes located in the southwest of Western Siberia (Central Eurasia). Based on measurements of pH, total dissolved solids (TDS), cationic and anionic composition, dissolved organic and inorganic C, as well as textural and mineralogical characterization of bottom sediments using X-ray diffraction and scanning electron microscopy, we demonstrate that lake water pH and TDS are primarily controlled by both the lithological and climatic context of the lake watershed. We have not revealed any direct relationships between lake morphology and water chemistry. The most common authigenic carbonates scavenging atmospheric CO2 in the form of insoluble minerals in lake sediments were calcite, aragonite, Mg-calcite, dolomite and hydromagnesite. The calcite was the most common component, aragonite mainly appears in lakes with sediments enriched in gastropod shells or artemia cysts, while hydromagnesite was most common in lakes with high Mg/Ca molar ratios, as well as at high DIC concentrations. The relationships between mineral formation and water chemistry established in this study can be generalized to a wide suite of arid and semiarid lakes in order to characterize the current status of the inorganic C cycle and predict its possible modification under on-going climate warming such as a rise water temperature and a change in hydrological connectivity, primary productivity and nutrient regime. [ABSTRACT FROM AUTHOR]

Wing morphology has been used in taxonomic and systematic studies of insects, often enabling the identification of groups based on the variation. In this study, wing Geometric Morphometrics was used to verify if eastern and western populations of Partamona rustica, separated by the São Francisco River, are discriminated, thus confirming previous molecular data. The two groups of P. rustica exhibited significant differences in wing size and shape. Better differentiation of populations and groups was achieved with the centroid size. We generated dendrograms using Mahalanobis and Procrustes distances, which discriminated the eastern and western populations. Isolation by the distance between morphometric and geographic distances was found. The confirmation of the two population groups points out the need for further studies investigating the occurrence of barriers to gene flow and colonization history in the semiarid region by this stingless bee. [ABSTRACT FROM AUTHOR]

Copyright of Revista Caatinga is the property of Revista Caatinga and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Caatinga is the property of Revista Caatinga and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This article presents a study on the spatiotemporal dynamics of land cover and use, vegetation indices, and water content in the semiarid region of Pernambuco, Brazil. This study is based on an analysis of satellite images from the years 2016, 2018, and 2019 using the MapBiomas platform. The results show changes in the predominant land cover classes over time, with an increase in the caatinga area and a decrease in the pasture area. An analysis of the vegetation indices (NDVI and LAI) indicated low vegetation cover and biomass in the study area, with a slight increase in the NDVI in 2018. An analysis of the Modified Normalized Difference Water Index (MNDWI) showed that the water content in the study area was generally low, with no significant variations over time. An increase in the water bodies, mainly due to the construction of a reservoir, was noted. The results of this study have provided important information for natural resource management in the region, including the development of strategies for the sustainable use and management of natural resources, particularly water resources, vegetation cover, and soil conservation. [ABSTRACT FROM AUTHOR]

Abstract The aim of this study was to conduct a floristic inventory and update the geographical distribution of Talinaceae species in Ceará state, in the Northeast Region of Brazil. The study was based on a comparative analysis of morphological characters of specimens deposited in the EAC, ESA, HCDAL, HUEFS, HUVA, HVASF, MOSS and RB herbaria, specialized literature, photos of type collections, and field expeditions conducted between March 2015 and April 2022. For the state, Talinum fruticosum and T. paniculatum have been recorded, which prefer drier vegetations, such as Stepic Savanna (Caatinga and Carrasco) and Semideciduous Seasonal Forest (Mata Seca), but also grow in areas that are more humid. The species occur in eight conservation units in Ceará: Dunas da Lagoinha and Serra de Meruoca Environmental Protection Areas, Aiuaba Ecological Station, Sobral National Forest, Ubajara National Park, Pedra da Andorinha Wildlife Refuge, Serra das Almas and Fazenda Trussú Private Natural Heritage Reserves. An identification key, descriptions, photographs, and comments about the geographical distribution, taxonomic relationships, and phenology are provided for the species.

Copyright of Revista Caatinga is the property of Revista Caatinga and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Evidence exists that the Caldenal (caldén (Prosopis caldenia) forest) of the Semiarid Pampas Region functions as a sink of aeolian sediments. These sediments accumulate on a layer of volcanic ash deposited in 1932, which allows to analyze the degree of soil evolution in a 90-year period. Therefore, some physical, chemical and morphological properties of the superficial soil horizon (Ah) of a caldén forest, which evolves from those sediments, were evaluated from windward to leeward. The results indicated that the evolution of the soil was incipient, although soil development tended to be better towards windward than at leeward. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the effect of organic selenium (SE) supplementation on blood constituents related to hematology and serum biochemistry of dairy goats in the productive phase. A total of 16 lactating Saanen × Toggenburg crossbred goats, aged between 2 and 3, lactating, nonpregnant, clinically healthy, and having a body weight (BW) of 40.75 ± 8.31 kg were selected for this study. Higher SE concentrations were observed on the 42nd day of supplementation, and on the 63rd day, the SE concentrations were similar ( P > 0.05 ) to the 21st and 42nd days. There was no interaction for plasma constituents comparing treatment effects and days of supplementation ( P > 0.05 ). SE supplementation reduced ( P = 0.04 ) plasma proteins with a gradual increase in available SE. There was no difference ( P > 0.05 ) for the blood count comparing the effects of treatment and days of supplementation. There was no interaction ( P > 0.05 ) for serum biochemical constituents between treatments and periods, except for urea ( P = 0.045 ). Animals that received SE supplementation had similar plasma urea concentrations before and after supplementation, while animals that did not receive SE in the diet had increased serum urea concentrations. The main action of selenium in metabolism occurred in the reduction of plasma proteins and urea levels, which leads us to conclude that it influenced protein metabolism. Finally, hematology, liver function, and energy metabolism are not affected by selenium supplementation in dairy goats reared in semiarid conditions. [ABSTRACT FROM AUTHOR]

In this study, the physical and chemical characteristics of groundwater quality parameters of 16 wells within the M’Sila region were used for calculations such as sodium adsorption ratio (SAR), Kelly’s ratio (KR), sodium percentage (Na %), permeability index (PI) and magnesium hazard (MH), which are used in irrigation water quality ratings. Also, the irrigation water quality index (IWQI) was calculated for all ground water sources within the study area. The correlations between the irrigation water quality parameters were determined using Pearson correlation analysis. The SAR, KR, and NA % values in the study area show that the groundwater in the study area is excellent and good as such suitable for irrigation purposes. Evaluation of the suitability of the groundwater in the study area for irrigation based on MH and WQI also suggests that 31.25 % and 37.5 % respectively of the samples are suitable and excellent or good for irrigation. The PI values show that the ground waterfalls under Class III, making the groundwater ‘unsuitable’ for irrigation. The groundwater in the study area is acceptable for irrigation except for a few instances which require a special careful application.

Plant growth-promoting bacteria (PGPB) are bacteria that can enhance protect native plants from abiotic stresses including drought. The inoculation of these PGPB into crop forage plants may increase productivity helping to suppress its growing demand in semiarid regions. The present paper aims to evaluate the Sorghum bicolor L. morphogenic characteristics and growth inoculated with native bacterial isolates from the Brazilian semiarid region under drought conditions. The endophytic bacteria isolated from root nodules of native leguminous plants named Mimosa tenuiflora (isolates – MTBV77, MTP78, MTBV12), Desmanthus pernambucanus (isolates – DPP1) and Mimosa caesalpiniifolia (isolate – MCLR34) were all presumably identified as rhizobia by performing the Polymerase Chain Reaction duplex amplification technique using primers that amplify the nifH and nodC genes. The seeds and roots of sorghum seedlings were inoculated with bacterial isolates. The plants were cultivated in pots under favorable water conditions (80% of the available water) and dry conditions (40% of the available water). The inoculation with bacterial isolates increased emission, elongation and length of the S. bicolor leaves, as well as increased its stem elongation, height, and shoot dry-matter content. However, the magnitude of the effects varied according to the imposed water regime. Thus, rhizobacteria from root nodules of Brazilian native legumes have the potential to promote plant growth. The bacterial isolates DPP1 and MTBV77 attenuate the effects of water stress and promote S. bicolor growth under drought conditions and are therefore promising for the use as an inoculant for S. bicolor sustainable cultivation to forage purposes. [ABSTRACT FROM AUTHOR]

The Ogallala Aquifer, located in the Central Plains of the United States, is essential for agricultural irrigation and public water supply. Indiscriminate pumping from the aquifer has caused several negative impacts, such as deterioration of water quality and depletion of groundwater levels, which urgently demand better management. This paper applies hierarchical cluster analysis (HCA) and artificial neural networks (ANNs) for predicting annual groundwater levels in 403 wells of the Ogallala Aquifer. First, the methodology employed HCA to cluster homogeneous wells based on the time series of groundwater levels. Then, the study calibrated an ANN model for each cluster (composed of one or more wells) using previous annual values of groundwater levels as input. The HCA results showed a particular pattern in the spatial distribution of the 30 found clusters, revealing that the Ogallala Aquifer holds higher groundwater levels in the western part, which gradually decrease, advancing to the east. The ANN models provided proper predictions even for wells outside of the calibration data set. This investigation concludes that the integration of HCA and ANN enabled single models to accurately forecast annual groundwater levels for sets of wells in the Ogallala Aquifer. [ABSTRACT FROM AUTHOR]

Management practices might alter soil chemical properties. This study evaluated soil chemical properties in a forage cactus Opuntia stricta (Haw.) Haw. (‘Orelha de Elefante Mexicana’) (OEM) production system in the Brazilian semiarid region. The experiment was established in June 2011, and the design was a split-split-plot in randomized complete blocks, in which the main plots were formed by distinct levels of organic fertilizer (cattle manure) (0, 10, 20, and 30 Mg ha−1 year−1), the subplots were formed by different levels of N inorganic fertilizer applied as urea (0, 120, 240, and 360 kg N ha−1 year−1), and the sub-subplots were distinguished by the distinct OEM harvesting frequency (annual or biennial). Soil samples were collected for chemical analysis, C and N contents analysis, and stocks analysis at 0 to 10 and 10 to 20 cm depths in August 2019. Organic fertilizer contributed to a linear increase in soil pH, Ca2+, Na+, sum of bases (SB), cation exchange capacity (CEC), and base saturation (V) at both depths (p < 0.05). With the application of 30 Mg ha−1 year−1 of cattle manure, there was storage of approximately 126 Mg C ha−1 and 13 Mg N ha−1 at 0 to 20 cm depths. Managing OEM with organic fertilizer and a biennial frequency of harvesting affects the soil’s chemical characteristics in cactus orchards, and it is a sustainable alternative for semiarid regions.

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective of this work was to evaluate the effect of different sources of phosphorus and its interaction with nitrogen, on the yield, quality, and nutrient extraction of the wheat crop. The field experiment was carried out on an entic Haplustol, in which 8 fertilization treatments (T) were established. T 1 corresponds to the control (without adding P), in T 2, 3, 4, and 5, 18,3 kg.ha-1 of P was applied. T 6, 7, and 8 correspond to fertilizer additions at recommended rates of 30 kg.ha-1 which implies the application of 5,25 kg of P.ha-1. Two nitrogen management procedures were established in divided plots: with and without fertilization. In all the treatments with phosphorus, the addition of N presented statistically significant differences in yield. The WUE was higher in those treatments whose fertilizers have a balanced formulation of nutrients. No significant differences in protein concentration were found. T 2, 3, 4, and 5 presented a positive balance between the P applied with fertilizer and extracted in the grain, T 6, 7, and 8 had a negative balance, while T 1 (control) was the worst situation. [ABSTRACT FROM AUTHOR]

The aim of this study was to conduct a floristic inventory and update the geographical distribution of Talinaceae species in Ceará state, in the Northeast Region of Brazil. The study was based on a comparative analysis of morphological characters of specimens deposited in the EAC, ESA, HCDAL, HUEFS, HUVA, HVASF, MOSS and RB herbaria, specialized literature, photos of type collections, and field expeditions conducted between March 2015 and April 2022. For the state, Talinum fruticosum and T. paniculatum have been recorded, which prefer drier vegetations, such as Stepic Savanna (Caatinga and Carrasco) and Semideciduous Seasonal Forest (Mata Seca), but also grow in areas that are more humid. The species occur in eight conservation units in Ceará: Dunas da Lagoinha and Serra de Meruoca Environmental Protection Areas, Aiuaba Ecological Station, Sobral National Forest, Ubajara National Park, Pedra da Andorinha Wildlife Refuge, Serra das Almas and Fazenda Trussú Private Natural Heritage Reserves. An identification key, descriptions, photographs, and comments about the geographical distribution, taxonomic relationships, and phenology are provided for the species. [ABSTRACT FROM AUTHOR]

Rural and isolated communities traditionally lack adequate water treatment and distribution systems, and water quality assessment often does not include radioactivity measurement. Here we present, for the first time, the results of Rn measurements and the evaluation of the associated dose in groundwaters of rural communities in a semiarid area in Paraiba State, Brazil. Water samples were analysed using a low-level liquid scintillation spectrometer (LSS). Radon concentrations were higher than EPA and WHO recommended levels in water for most of the wells (range of 5.5–1107.0 Bq/L, average 252.8 Bq/L). Higher Rn concentration was measured in deeper wells and located in area rich in granite and diorite rocks. The annual effective doses varied between 0.021 and 4.317 mSv/y for infants, 0.016–3.182 mSv/y for children, and 0.015–3.022 mSv/y for adults, exceeding, in some cases, the 1 mSv/y reference level recommended by the WHO and UNSCEAR for the public. Thus, water consumption from half of the wells should be avoided unless adequate treatment is provided. Results highlight the need to perform actions to supply water with appropriate quality to the local population. [ABSTRACT FROM AUTHOR]

Nonsessile animals could partition the use of resources in different axes, reducing the effects of competition and allowing coexistence. Here, we investigated the spatial and trophic niche dimensions in four lizard assemblages in the Neotropical semiarid Caatinga to investigate the determinants of resource use and the extent to which lizards partition their niches. We sampled each lizard assemblage once, for 10 days, in the dry season of 2017 and 2018. In two lizard assemblages, we detected nonrandom niche overlap patterns that were higher or lower than expected by chance. The high niche overlap patterns suggest that either there is intense current competition for available microhabitats or an abundance of microhabitats. The lower niche overlap may be influenced by the presence of species adapted to sandy habitats (psammophilous), suggesting that spatial partitioning detected has historical basis, which is supported by the pPCA results and by the lack of patterns in the realized niche distribution of species across niche space. We detected trophic niche partitioning in three lizard assemblages. In one assemblage, we discovered random spatial and trophic niche overlap patterns, revealing that competition is not a determining factor in the structure of that assemblage. In fact, phylogenetic effects were predominantly the main determinants of resource use in the four studied lizard assemblages. Arid and semiarid habitats cover about one third of land surface of the world. Comparisons between our findings and those from other regions of the world may aid identify general trends in the lizard ecology of dry environments. [ABSTRACT FROM AUTHOR]

Drought is a very complex natural phenomenon that affects the water supply and consequently impacts agricultural and socioeconomic activities, causing social and political crises. The objective of this study is to spatiotemporally analyze meteorological and agricultural droughts based on multiple indices in the Upper Paraíba River basin for the 2001–2017 period. The agricultural droughts were analyzed using four drought indices (NDVI, LST, VSWI, and VHI) based on data from the MODIS sensor on the TERRA and AQUA satellites, while the meteorological droughts were characterized using the standardized precipitation index (SPI) at three different time scales based on TRMM rainfall data. The values of LST, NDVI, VHI, VSWI, and SPI revealed how much vegetation is influenced by rainfall variability in this semiarid region of Brazil. The estimated results of VSWI and VHI show the years with extremely wet and dry conditions from spatial and temporal perspectives. The relationship between estimated drought indices and observed relative humidity showed that VSWI (R² = 0.78) was best fitted when compared to VHI (R² = 0.46). Thus, it can be concluded that the VSWI index is better adapted because it presented more consistent results for the behavior of agricultural droughts when compared to the VHI. The results of the SPI analysis were used for the identification of the main drought events that affected the study basin. This combined technique of different drought indices easily produced an alternative method for comprehensive drought assessment. [ABSTRACT FROM AUTHOR]

Projected climate changes integrated into future land-use changes are extremely complex and hard to estimate, especially for basins located in semiarid environments. This work aims to estimate streamflow and the future water yield using climate prediction and land-use changes in the Salgado River basin for the 2030 - 2060 period. In this study, the applicability of the Soil and Water Assessment Tool (SWAT) and Land Change Modeler models was verified to estimate flows and land use and cover for the studied basin. Calibration and validation of the SWAT model are used on a monthly basis for 1986- 2017, with a calibration period from 1986 to 2006 and a validation period from 2007 - 2017. Land use and cover analysis is performed for the 1985 - 2000 period, and future land use and cover is predicted using the land change model for 2050. In addition, future hydrological modeling of the geographical distribution of the water yield is performed for each subbasin of the Salgado River basin from the 2030 to 2060 period. The results of land use and cover changes show that the pasture class was the one that showed the most significant increase in the basin due to recent changes in land use and cover. The results showed that the HadGEM2-ES model presented a minor difference in the representative concentration pathways (RCP) 2.6, which indicates that this model is the most suitable for rainfall-runoff simulations in the region. [ABSTRACT FROM AUTHOR]

Seed germination is a key stage in the life history of plants, which has a crucial effect on plant community structure. Climate change has substantially altered the surface soil temperature and light availability, which can affect seed germination. However, whether the seed germination of different functional groups is affected by the interactions of light and temperature remains unclear. Under laboratory conditions, we examined the effects of low temperature and darkness, as well as their interaction, on the seed germination of 16 species belonging to three plant functional groups (annual and biennials, perennial grasses, and perennial forbs) in a typical steppe, Northern China. We found that low temperature had a significant negative effect on seed germination of all species. Low temperature significantly decreased the final germination percentage and germinative force of the three plant functional groups, and the germination duration of perennial grasses. Darkness significantly decreased the germinative force of perennial forbs and total seeds, and the germination duration of perennial grasses. The interactive effects of light and temperature on the seed final germination percentage and germinative force of perennial grass indicated that darkness strengthened the inhibitory effect of low temperature on the seed germination of the grass functional group. Our study indicate that the seed germination of different plant functional groups varied greatly in response to changing environmental conditions. Our results suggest that future climate change could alter the regeneration and species composition of plant communities through changing seed germination. [ABSTRACT FROM AUTHOR]

Eutrophication intensifies Harmful Macroalgae Blooms (HMBs) in coastal environments, reducing habitat suitability for organisms and creating significant challenges for small-scale artisanal fishers. Leveraging fishers' memories, we analyzed over 20 years of data on Ulva lactuca blooms and their effects on fishing activities and fish resources in a tropical semi-arid region of Brazil. We estimated the timing, seasonality, and impacts of these bloom episodes on fish catches, fishing gears, and fishery revenues. Since 2010, blooms have become more frequent, particularly during dry seasons in shallow estuaries, likely exacerbated by nutrient enrichment, extended water residence time, and inadequate wastewater treatment. Net-based gear is particularly affected, with fish catches decreasing by up to sevenfold during bloom seasons, leading to income losses of approximately 50 %. Addressing eutrophication through active public policies on effluent treatment is crucial to mitigating economic impacts on vulnerable communities and managing future blooms, which are expected to worsen with climate change. • Increasing Harmful Macroalgal Blooms threaten marine biodiversity and disrupt ecosystems. • Local Ecological Knowledge from fishers offers key insights into Ulva lactuca blooms in tropical semi-arid regions. • Fishers report U. lactuca blooms have increased since 2008, cutting incomes by up to 50 %. • Increased U. lactuca biomass reduces fish catches, impacting fishing productivity. • U. lactuca blooms require improved management for ecosystem health. [ABSTRACT FROM AUTHOR]

The use of algae-based biostimulants as biopromoters for the growth, flowering, and fruiting phases has been intensified in recent years, despite a lack of information about the ideal quantity for maximum efficiency by the plant. This study aimed to select the concentration and application timing of Ascophyllum nodosum-derived biostimulant capable of modulating the physiology and increasing the yield of soybean plants from a semiarid region. The trials were carried out in a greenhouse by applying leaf spraying of biostimulant at 0, 0.5, 1.0 and 1.5 L ha−1, as a single or double application, in different developmental stages (V4, V4 + R1, R1, R1 + R4) of Extrema soybean cultivar. Growth, water content, pollen viability, gas exchange and grain yield were investigated. The biostimulant promoted a better physiological conditioning and productive responses, depending on the dose and application timing. Ascophyllum nodosum-based biostimulant at 1.5 L ha−1, applied 0.75 L ha−1 at V4 + 0.75 L ha−1 at R1 (T12), was the most significant treatment, improving the net photosynthesis, water status and plant growth, which resulted in a 12% increase in grain yield. In conclusion, the dosage and timing of application play pivotal roles in eliciting physiological and productive responses through biostimulants. Seaweed-based biostimulants emerge as essential components to optimizing the cultivation and yield of soybean plants, serving as efficient and sustainable biological regulators. [ABSTRACT FROM AUTHOR]

In the face of urban expansion, ensuring sustainable water consumption is paramount. This study aims to develop a domestic water demand forecast model that considers population heterogeneity and the urban area distribution in a city in the Brazilian Semiarid Region. The methodology comprises three main steps: (1) spatial data collection to identify explanatory variables for a future Land Use and Cover (LULC) model; (2) simulation of LULC data for 2030, 2040, and 2050 using the MOLUSCE plugin; and (3) estimation of domestic water demand based on projected urban area expansion and a linear regression model incorporating demographic indicators of household income, residents per household, total population, and gender. The results demonstrated a consistent LULC simulation, indicating an urban expansion of 4 km2 between 2030 and 2050, with reductions of 0.6 km2 in natural formations and 3.4 km2 in farming areas. Using LULC data, the study predicted a 14.21% increase in domestic water consumption in Campina Grande for 2050 compared to 2010, equivalent to an increase of 2,348,424.96 m3. Furthermore, the spatial analysis draws a spatial profile of water consumption among residents, highlighting the areas with the highest per capita consumption. Thus, this research offers a consistent approach to estimating water demand in regions with limited consumption data, providing valuable insights for decision-makers to consider in urban planning.

Towards a better understanding of factors controlling carbon (C) exchange between inland waters and atmosphere, we addressed the inorganic carbon cycle in semiarid lakes of Central Eurasia, subjected to the strong impact of on-going climate change. As such, we assessed the hydrochemical variability and quantified its control on the formation of authigenic carbonate minerals, occurring within the upper layer of sediments in 43 semiarid lakes located in the southwest of Western Siberia (Central Eurasia). Based on measurements of pH, total dissolved solids (TDS), cationic and anionic composition, dissolved organic and inorganic C, as well as textural and mineralogical characterization of bottom sediments using X-ray diffraction and scanning electron microscopy, we demonstrate that lake water pH and TDS are primarily controlled by both the lithological and climatic context of the lake watershed. We have not revealed any direct relationships between lake morphology and water chemistry. The most common authigenic carbonates scavenging atmospheric CO2 in the form of insoluble minerals in lake sediments were calcite, aragonite, Mg-calcite, dolomite and hydromagnesite. The calcite was the most common component, aragonite mainly appears in lakes with sediments enriched in gastropod shells or artemia cysts, while hydromagnesite was most common in lakes with high Mg/Ca molar ratios, as well as at high DIC concentrations. The relationships between mineral formation and water chemistry established in this study can be generalized to a wide suite of arid and semiarid lakes in order to characterize the current status of the inorganic C cycle and predict its possible modification under on-going climate warming such as a rise water temperature and a change in hydrological connectivity, primary productivity and nutrient regime.

The sunflower is an oilseed species, rustic, cultivated in different agroecosystems. The responses of cultivars to nitrogen fertilization vary according to the cultivar and environment. Therefore, this research aimed to evaluate the response of biometric characters of sunflower cv. Embrapa 122-V2000 under N doses. The experiment was carried out in a randomized block design with five treatments (0, 40, 80, 120 and 160 kg N ha-1) and four blocks. All characters were influenced (p

Afforestation is an effective approach to rehabilitate degraded ecosystems, but often depletes deep soil moisture. Presently, it is not known how an afforestation‐induced decrease in moisture affects soil microbial community and functionality, hindering our ability to understand the sustainability of the rehabilitated ecosystems. To address this issue, we examined the impacts of 20 years of afforestation on soil bacterial community, co‐occurrence pattern, and functionalities along vertical profile (0–500 cm depth) in a semiarid region of China's Loess Plateau. We showed that the effects of afforestation with a deep‐rooted legume tree on cropland were greater in deep than that of in top layers, resulting in decreased bacterial beta diversity, more responsive bacterial taxa and functional groups, increased homogeneous selection, and decreased network robustness in deep soils (120–500 cm). Organic carbon and nitrogen decomposition rates and multifunctionality also significantly decreased by afforestation, and microbial carbon limitation significantly increased in deep soils. Moreover, changes in microbial community and functionality in deep layer was largely related to changes in soil moisture. Such negative impacts on deep soils should be fully considered for assessing afforestation's eco‐environment effects and for the sustainability of ecosystems because deep soils have important influence on forest ecosystems in semiarid and arid climates. [ABSTRACT FROM AUTHOR]

The sunflower is an oilseed species, rustic, cultivated in different agroecosystems. The responses of cultivars to nitrogen fertilization vary according to the cultivar and environment. Therefore, this research aimed to evaluate the response of biometric characters of sunflower cv. Embrapa 122-V2000 under N doses. The experiment was carried out in a randomized block design with five treatments (0, 40, 80, 120 and 160 kg N ha-1) and four blocks. All characters were influenced (p<0.05) by N doses, fitting to the quadratic model. The maximum values of plant height (1.68 m), stem diameter (22.71 mm), leaf area (423.41 cm2), capitulum diameter (15.22 cm), dry biomass yield (6,075.13 kg DM ha-1) and grains (2,982.89 kg ha-1), N use efficiency from biomass (80.3 kg kg-1) and grains (43.27 kg kg-1) close to 90 kg N ha-1, this dose being recommended for the edaphoclimatic conditions of the Agreste Meridional Region of Pernambuco, Brazil. [ABSTRACT FROM AUTHOR]

Copyright of Sustainability in Debate / Sustentabilidade em Debate is the property of University of Brasilia, Center for Sustainable Development and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)