Hydrographic Regions Research Articles

Large sampling effort is not related to richness and geographic distribution of Cladocera (Crustacea, Branchiopoda) in the Brazilian Savannah

ABSTRACT The Cerrado is home of the headwaters of some important Brazilian basins. Such biome has a high diversity of animal and plant species with a high degree of endemism. This premise is well documented for microcrustaceans of the Superorder Cladocera, although many areas still need sampling. In this context, the objective of the present investigation was to evaluate the geographic distribution and richness of Cladocera in the Cerrado biome. The analyzed data were obtained from the authors database on Brazilian Cladocera and distributed according to the hydrographic regions comprised in the biome. Species distribution models were used to determine the areas with the highest probability of occurrence of Cladocera. We analyzed 125 publications, resulting in 2829 records. In total, we obtained 161 taxa, belonging to 48 genera and seven families. Regarding the Hydrographic Regions, Paraná presented the highest richness, followed by TocantinsAraguaia and São Francisco. Our result indicates that most studies are concentrated in certain areas. Furthermore, the species distribution models indicated that transition areas between biomes have the highest probability of occurrence of genera and families. Our results indicate significant gaps in the knowledge, making it necessary to expand inventories and ecological studies in areas still unsampled.

Climate change and scarcity of water resources in Algeria

The importance of work is due to the importance of water in the continuation of human life and its great role in practicing its various activities, which concern industry, agriculture and various fields. The research methods included the increasing scarcity of water resources resulting from the decrease in the quantities available to the individual, the deterioration of the quantity and the objectives of economic and social development, thus imposing the development and definition of a water management strategy in the medium and long term. In recent years, the water scarcity crisis has increased and exacerbated due to the drought wave that the region suffers from, and it has greatly affected the region. As a result of the research, by the year 2025, a deficit of one billion cubic meters of water will be recorded. It is also possible to avoid this deficit in the hydrographic region of Constantine – Seybousse – and this is due to the dams that are in the process of being completed. In order to eliminate the shortage of water in the region, the amount of storage in dams must be increased and water desalination plants should be established in several areas in order to re-use wastewater. We can also avoid the shortage in the amount of water by building small dams and hill reservoirs, and this is to avoid siltation in large dams. Among the solutions are also increasing surface and groundwater resources, searching for new resources, dealing with losses, and improving the quality of available water.

Water balance components and climate extremes over Brazil under 1.5°C and 2.0°C of global warming scenarios.

The online version contains supplementary material available at 10.1007/s10113-023-02042-1.

Influence of fine-scale habitat characteristics on sage-grouse nest site selection and nest survival varies by mesic and xeric site conditions

AbstractResource managers and scientists across western U.S. agencies seek methodologies for identifying environmental attributes important to both wildlife conservation and broad-scale land stewardship. The Greater Sage-Grouse (Centrocercus urophasianus; hereafter, sage-grouse) exemplifies a species in need of this broad-scale approach given widespread population declines that have resulted from loss and degradation of habitat from natural and anthropogenic disturbances. These include agricultural land conversion, conifer expansion, energy development, and wildfire coupled with ecological conversion by invasive plants such as cheatgrass (Bromus tectorum). Development of habitat assessments and conservation actions for sage-grouse benefit from studies that link demographic responses to habitat selection patterns. To address this, we examined nest survival of sage-grouse in relation to fine-scale habitat patterns (i.e., field-based habitat measurements) that influenced nest site selection, using data from nests of telemetered females at 17 sites over 6 years in Nevada and northeastern California, USA. Importantly, sites spanned mesic and xeric average precipitation conditions that contributed substantially to vegetation community structure across cold desert ecosystems of the North American Great Basin. Vegetative cover immediately surrounding sage-grouse nests was important for both nest site selection and nest survival, but responses varied between mesic and xeric sites. For example, while taller perennial grasses were selected at xeric sites, we found no evidence of selection for perennial grass at mesic sites, indicating a functional response to availability of habitat features between hydrographic regions. Furthermore, perennial grass height and forb height both had positive effects on nest survival at xeric sites, but we found varying effects at mesic sites. We emphasize that precipitation conditions driving ecosystem productivity vary regionally among sagebrush communities, shaping vegetation structure and suitable habitat conditions for nesting sage-grouse.

Atmospheric and Oceanic Patterns Associated with Extreme Drought Events over the Paraná Hydrographic Region, Brazil

The Paraná Hydrographic Region (PHR) is one of the main hydrographic basins in Brazil, standing out for its energy generation and consumption, among other ecosystem services. Thus, it is important to identify hydrological drought events and the driest periods inside of these droughts to understand the anomalous atmospheric circulation patterns associated with them (a multiscale study). This study used the standardized precipitation index (SPI) for the 12-month scale to identify hydrological drought episodes in the PHR from 1979 to 2021. For these episodes, the severity, duration, intensity, and peak were obtained, and the SPI-6 was applied to the longest and most severe drought to identify periods with dry conditions during the wet season. Anomalous atmospheric and oceanic patterns associated with such episodes were also analyzed. The results reveal that the longest and most severe hydrological drought on the PHR started in 2016. The end of this episode was not identified by the end of the analyzed period. The SPI-6 revealed three rainy seasons during this drought event marked by anomalous dry conditions: 2016/2017, 2019/2020, and 2020/2021. In general, the circulation patterns identified differ in each period, for example, in 2016/2017, an El Niño event was dominant, in 2019/2020, the tropical Pacific Ocean showed neutral conditions, and in 2020/2021, a La Niña episode was registered. Despite that, in the three periods, the anomalous atmospheric patterns contributed to the weakening of the low-level jet east of the Andes and, consequently, to the decreasing of the moisture transport to the PHR, then leading to dry conditions over the basin.

Entre o passado e o presente: seguindo os passos dos naturalistas do século XIX e sua contribuição para o conhecimento da ictiofauna brasileira

Abstract Aim To evaluate the contribution of naturalists Francis de Castelnau, Jacob Heckel, Johan Baptist von Spix, Johann Natterer, Louis Agassiz, and Rudolf Kner to the knowledge of taxonomic diversity of freshwater ichthyofauna in Brazil between the years 1829 and 1859. Methods Two data matrices were constructed: one with information on freshwater fish species known in Brazil until 2021 and another based on the list of fish species in South America presented by Castelnau (1855). Both were supplemented with information on taxonomy, geographic distribution, authorship, and geographic distribution. The Taxonomic Diversity Index (Δ) was calculated from the first matrix to assess the contribution of the naturalists and determine the number of species per hydrographic region. The second matrix allowed for a detailed analysis of Francis de Castelnau's contribution. Results Between 1829 and 1859, the five naturalists considered in this study described 171 fish species in Brazil, including several endemic species. Castelnau was the naturalist with the greatest contribution (Δ=87.7), followed by Agassiz (85.5), Spix & Agassiz (85.4), Kner (80.8), and Heckel (48.7). The five naturalists described species from four hydrographic regions: the Amazon (122 species), Paraná (25), Tocantins-Araguaia (18), and São Francisco (13). The 276 fish species cataloged by Francis de Castelnau are mostly from the Neotropical region, including some endemics, originating from watercourses in the southeastern Brazilian region, encompassing species collected for the first time in the watercourses of Central Brazil and some marine species, ranging from small (5 cm) to medium (56.0 cm) in size. Conclusions The five naturalists considered in the study made a significant contribution to the early scientific knowledge (1829-1859) of the Brazilian ichthyofauna, but this contribution varies among the naturalists, with particular emphasis on Castelnau, Agassiz, and Spix & Agassiz, as well as among the hydrographic basins, notably the Amazon.

Dinâmica e manutenção do serviço ecossistêmico de manutenção da purificação da água na Região Hidrográfica do Rio Guandu, Rio de Janeiro, Brasil

ABSTRACT The present study aimed to develop a methodology for analyzing the dynamics and maintenance of the water purification ecosystem service in the water bodies of the Guandu River Hydrographic Region, responsible for water supplying the Rio de Janeiro Metropolitan Region, characterized by the presence of water transfers and low levels of effluent treatment. The dynamics of this service occurs through an ecosystem flow, influenced by the volume of water that moves from one region to another. The methodology consisted of reviewing studies of ecosystem flows, building a database, classifying impacts on water purification in hydrological planning units from a similarity dendrogram, analyzing indicators related to water demands and availability of these units, and developing an ecosystem flow diagram of water purification. The effects of transfers on the maintenance and flow of water purification were also analyzed from the comparison between the real scenario (which considers the presence of the existing hydraulic infrastructure) and the natural scenario (which disregards it). The results showed that the worst situation of maintenance of water purification is in the western part of the region, and the demands for it requires more than double the volume of withdrawn water to supply the local population and industry.

Stochastic modelling of the daily precipitation occurrence in the Tocantins-Araguaia hydrographic region, Amazon, Brazil

Evaluating the temporal and spatial variation of the occurrence of dry and rainy days is essential for planning the use of water resources. This article evaluated the behaviour of daily precipitation in the Tocantins-Araguaia hydrographic region (TAHR). The 1st-order stationary Markov chain (MC) of two states was used without considering the spatial correlation between the rainfall gauge stations. The developed model was efficient in estimating the occurrences of daily precipitation for the entire TAHR, as the maximum errors found were equal to RMSE: 14.1568, RSR: 0.0149, NSE: 0.9973 and PBIAS: -1.7650. However, the areas located in the Amazon-Cerrado Biome (Ecotone) require more attention due to the greater occurrence of consecutive drought days. Therefore, it is suitable to use MCs of higher orders for greater accuracy. In addition, the transition probabilities that led to rain conditions were greater when they were closer to the Atlantic Ocean, while the transition probabilities that led to drought conditions were greater in the areas located in the Cerrado biome.

NOVO MARCO REGULATÓRIO DA AQUICULTURA NO ESTADO DO PARÁ: ESCLARECIMENTOS NECESSÁRIOS

The development of an economic activity inevitably involves a clear legislation with sustainable bases, aiming at the ability of commercial initiatives to be profitable and maintain a lasting harmonious relationship with ecosystems and local communities. The need to elucidate state legislation that has exactly the same guidelines as federal legislation in force for more than a decade and in consolidated regulatory frameworks for federal units that share the same biome and the same hydrographic regions lies mainly in the existence of interests hidden individuals, who seek to confuse society and even distort the truth regarding the new regulations. This article represents an initiative to combat misinformation, as well as an encouragement to State of Pará aquaculturists who have demanded so much legal certainty to regularize their initiatives.

The conception of GIS to evaluate the impact of anthropogenic activities on the quality of surface waters of the dams of the hydrographic region of Constantinois-Seybouse-Mellegue, Algeria

The conception of GIS to evaluate the impact of anthropogenic activities on the quality of surface waters of the dams of the hydrographic region of Constantinois-Seybouse-Mellegue, Algeria

The role of natural and anthropic factors in the variability of soil loss in the state of Goiás between 1985 and 2018

Soil loss depends on natural and anthropic factors with high spatial and temporal variability, and can be inferred by predictive models such as the Revised Universal Soil Loss Equation (RUSLE). In this sense, the objective of this work is to analyze the spatio-temporal distribution and variation of soil losses in the state of Goiás for the years 1985, 2000 and 2018, based on the application of RUSLE and using the drainage basin as a multiscale unit of analysis. The results generally show that there has beenan increase in the average loss of soils in the state between the observed years with the average in 1985 being 2.4 ton.ha-1.year-1, growing to 10.8 ton.ha-1.year-1 in 2000, and 11.56 ton.ha-1.year-1 in 2018. The hydrographic regions of Tocantins and Paraná presented the highest losses. In addition to the general control of the Cerrado conversion expansion, the state of Goiás presents two spatial soil loss patterns; one in which the control of natural factors predominates, being linked to morphogenetic aspects with a strong influence of the topographic factor; and the other being rain erosivity, spatialized in areas such as the “front” of Cuesta Caiapó, Serra Dourada and Serra dos Pireneus. When associated, these two factors define sensitive areas with the highest soil losses in the state of Goiás.

Towards a synthesis of the biodiversity of freshwater Protozoa, Rotifera, Cladocera, and Copepoda in Brazil

Although Brazil is considered a megadiverse country, its rich freshwater biodiversity is still poorly known. A general overview of to-date knowledge on Protozoa, Rotifera, Cladocera, and Copepoda species and distribution in Brazilian Hydrographic Regions is presented here, based on literature data since the 1890s. Ecological studies provided most of the occurrence records. The results show high richness for all studied biological groups and unequal distribution of the occurrence records, which are substantially influenced by research groups’ location. The data also revealed that Brazilian zooplankton biodiversity still needs to be better studied, taxonomically, although from the beginning of the last century until 1980 these kinds of studies were predominant.

A Hydro-Economic Model to Support Water Scarcity

Climate variability is reflected in water affluence that directly impacts the availability and level of water in reservoirs. Economic instruments, such as tariffs, are increasingly being used to promote the rational use of water. This study offers a floating rate model for charging raw water as a function of the reservoir level. The model was designed in the Jaguaribe–Metropolitan System, a place characterized by water-use conflicts during water scarcity. The model was developed as a function of the unit payment capacity (UPC) and drought states of the hydrographic regions. We applied the free software R and PSO optimization package to define the optimal UPC fraction and evaluated the model sensitivity using a synthetic series generated with the Markov chain method. Consequently, we observed that comfortable, alert, and critical situation levels predominated in the sensitivity analysis, and the average collections paid for administration, operation, and maintenance (AO&M) costs. In some cases, a collection surplus that can be managed through a financial fund to finance the system in periods of critical shortage is generated.

Multi-sensor geodetic observations for drought characterization in the Northeast Atlantic Eastern Hydrographic Region, Brazil

The lowest water availability area in Brazil is the Northeast Atlantic Eastern Hydrographic Region (NAERH). It plays a fundamental role in the lives of 24.1 million inhabitants spread throughout 874 cities. Drought is recurrent in this semiarid climate, affecting agriculture, biodiversity, the ecosystem and other environmental spheres. Therefore, the goal of this research is to combine different drought indexes to quantify drought intensity and duration in the NAERH. Besides the traditionally used rainfall data, multi-temporal data from the Gravity Recovery and Climate Experiment (GRACE) and Global Positioning System (GPS) were also used. The indexes are the Combined Climatic Deviation Index (CCDI), Drought Severity Index (DSI) and Vertical Crustal Deformation Index (DIVCD). The Standardized Precipitation Index (SPI) was used for validation of the other indexes through the Spearman rank correlation, which retrieved ρ = 0.76 and 0.68 between the CCDI and the SPI-03/06. On the other hand, DSI correlated with the SPI-24/36 with ρ = 0.67/0.75. Despite limitations, the DIVCD accurately detected the frequencies of hydrological droughts. All indexes identified the last severe drought from 2012 to 2018, and its persistence throughout 2019 and 2020. The combined indexes approach reveals nuances of the indexes, improving the baseline to thoroughly understand drought at different temporal scales.

Geotechnologies as decision support strategies for the identification of fire-susceptible areas in Rio de Janeiro State.

Forest fires have global, regional, and local socioeconomic and environmental consequences, with negative effects on ecosystem services, air quality, population health, and other relevant aspects, emphasizing their significance in the context of the United Nations Sustainable Development Goals. The study identified areas in the Rio de Janeiro State (RJS) with varying degrees of susceptibility to fire focis using remote sensing data derived from topographic, anthropogenic, meteorological, and hydrological factors based on seasonality and integrated into geographic information systems. The analytical hierarchy process was used as a method of integration and normalized hierarchy of variables, generating susceptibility maps in the annual, summer, and winter periods in the RJS's hydrographic regions (HR), with the application of the associated chi-square test to records of fire focis from the AQUA satellite, period 2003 to 2017, without methodological variation for data acquisition, whose susceptibility was classified as very low to very high. The results show that the years with the most fire foci in the adopted time series are 2007 and 2014, with a peak in September and a fall from October onwards. According to the susceptibility map, 9% of the RJS is highly susceptible during the annual period, with HR-IX being especially vulnerable. In the summer, 0.2% of RJS is extremely vulnerable, while 32% is highly vulnerable in the winter, with 6402 km2 of HR-IX areas being extremely vulnerable. A statistical correlation was discovered between the chi-square test and susceptible areas. This work contributes as a decision-making tool in fire planning and emergency response, with the potential to assist control bodies (city halls, civil defense, environmental protection bodies, health systems) in the local and regional context in the assessment, analysis, and management of these phenomena.

VULNERABILIDADE DO SOLO À EROSÃO HÍDRICA, REGIÃO HIDROGRÁFICA DO GUAÍBA-RS

O aumento populacional nos últimos anos está desencadeando avanços no uso da terra de modo inadequado e sob a ocorrência extremos climáticos acarreta inúmeros desastres naturais, dentre eles a erosão do solo. O objetivo deste trabalho é analisar a vulnerabilidade a erosão hídrica do solo na Região Hidrográfica do Guaíba-RS. Ultilizou-se dados estimados de precipitação (Global Precipitation Climatology Center); uso da terra (Projeto MapBiomas); declividade (Instituto Nacional de Pesquisas Espaciais) e de solo (Empresa Brasileira de Pesquisas agropecuária) na álgebra de mapas para obter o produto de erosão hídrica do solo. A região hidrográfica do Guaíba apresentou estabilidade ao norte e a sudeste, porém, áreas extremamente instáveis foram detectadas principalmente no eixo central (leste-oeste) com alguns pontos ao sul. Os processos erosivos da região são motivados naturalmente pela declividade e solo, onde a precipitação não é um fator preponderante na erosão, sendo este desastre ocasionado em alguns pontos pela forçante antrópica. O controle das áreas instáveis através preservação da cobertura vegetal e diminuição do avanço agrícola é essencial para a prevenção de possíveis casos de erosão, prejuízos socioambientais e econômicos.

Use of Game Theory as a tool for identifying and mitigating conflicts over water use in the area covered by the Estreito HPP – MA- Brazil

Game Theory (JT) is a mathematical theory that assesses in the strategy games the understanding and interaction of the actors, being an important tool in the identification and analysis of conflicts. Therefore, the objective was to analyze conflicts over water use and propose mitigating measures in the Hydrographic Region of the Middle Tocantins, applying after the identification of possible conflict-generating agents, the JT. This made it possible to identify the conflict scenarios and the degree of intensity in which they occur, varying at high, medium and low levels. The "players" reported that many environmental impacts and conflicts could be avoided if communication were better, emphasizing the need to create a basin committee, which will allow greater interaction between users. Therefore, the JT when used as a tool to identify conflict scenarios due to the use of water, proves to be quite effective, enabling the modeling of scenarios to minimize conflicts.

Trend Detection in Annual Streamflow Extremes in Brazil

Changes in streamflow extremes can affect the economy and are likely to impact the most vulnerable in society. Estimating these changes is crucial to develop rational adaptation strategies and to protect society. Streamflow data from 1106 gauges were used to provide a comprehensive analysis of change in eight different extreme indices. The modified trend-free prewhitening and the false discovery rate were used to account for serial correlation and multiplicity in regional analysis, issues shown here to distort the results if not properly addressed. The estimated proportion of gauges with significant trends in low and high flows was about 23% and 15%, respectively. Half of these significant gauges had more than 60 years of data and were associated with changes greater than 5% per decade. A clear spatial pattern was identified, where most increasing trends in both low and high flows were observed in Southern Brazil, and decreasing trends in the remaining regions, except for the Amazon, where a pattern is not clear, and the proportion of significant gauges is low. Results based only on gauges unaffected by reservoirs suggest that reservoirs alone do not explain the increasing trends of low flows in the southern regions nor the decreasing trends in high flows in the remaining hydrographic regions.

Water reuse in industries: analysis of opportunities in the Paraíba do Sul river basin, a case study in Presidente Vargas Plant, Brazil.

In recent years, the demand for clean water has been growing all over the world despite the different threats posed, including increasing pollution, increasing deforestation and climate change. Industrial activity is the second largest consumer of water, so highly industrialized regions are more susceptible to water stress. In this sense, reuse strategies have been progressively discussed and used around the world; however, in Brazil there is still place for many advances, whether due to lack of incentives, cultural issues in society, or poor regulation of the subject. The objective of this work was to carry out a diagnosis of raw water uptake by industries in one Hydrographic Region of the state of Rio de Janeiro and to propose a discussion on the adoption of water reuse practices for non-potable purposes from the use of treated effluents. A survey of the theoretical framework on the subject was carried out, as well as an analysis of sustainability indicators and reports of the companies, including the current licensing processes of large undertakings consuming water resources. With this study, it was possible to obtain the average cost of implementing a water reuse unit for an industry in the state of Rio de Janeiro-Brazil, which, despite still being expensive, has a strong tendency to use due to world water shortages. Finally, it was concluded that the state of Rio de Janeiro has a threat of water scarcity that could be aggravated in the coming years, if measures and investments in supply alternatives are not adopted (water reuse), and improvement in all stages of water management water resources.

Modeling Streamflow at the Iberian Peninsula Scale Using MOHID-Land: Challenges from a Coarse Scale Approach

Hydrological modeling is nowadays critical for evaluating the status, past trends, and future perspectives of water availability at the global, regional, and local scales. The Iberian Peninsula is registering more frequent and severe droughts and water scarcity caused not only by extreme meteorological events, but also by increased demand for water for urban, industrial, and agricultural supplies. Better simulation models are thus needed for accurately quantifying the availability of local water resources. In this study, the natural flow regime in different watersheds of the Iberian Peninsula was simulated using the process-based, fully distributed, MOHID-Land model from 1979 to 2013. Streamflow results were compared with measurements at 73 hydrometric stations not influenced by reservoirs, and with the data available in the management plans of each hydrographic region. The results showed a high dispersion of the goodness-of-fit indicators, with the coefficient of determination (R2) ranging between 0 and 0.91, and the modeling efficiency (NSE) being higher than 0.35 at only 22 (calibration) and 28 (validation) hydrometric stations. Considering the scale of application, results were acceptable but evidenced the difficulties in simulating streamflow in watersheds using a coarse resolution. As such, this paper further deals with the difficulties and challenges of the adopted modeling approach. Nevertheless, this study constitutes a further step towards the more accurate assessment of water resources availability at the Iberian Peninsula scale using process-based modeling.