Wetland ecosystems are one of the most important areas that provides different ecosystems services as well as habitat for plant and animal species. In spite of multipurpose, wetland ecosystems are under threats. This study attempts to analyze wetland dynamics of Abay Choman and Jimma Geneti watershed in Horo Guduru Wollega Zone, Western Ethiopia using geospatial techniques. The land use land cover (LULC), the Normalized Difference Vegetation Index (NDVI), and Normalized Difference Water Index (NDWI) were investigated using Landsat 5 TM of 1991, Landsat 7ETM+ of 2003, and OLI/TIRS of 2021. In the present study, the LULC was classified using a supervised classification method with maximum likelihood algorithm. The red and infrared bands of Landsat imagery from three different time periods were used to calculate NDVI, while the NDWI was estimated using the green and near infrared (NIR) bands of multispectral Landsat images. Results show that wetland ecosystem in the study area decreased by about 125.2 km² (8.8%) with the rate of 4.2 km²/year. In contrast, agricultural land increased by 223.4 km² with the rate of 7.4 km²/year between 1991 and 2021. About 66.7 km² wetland was converted to cultivated land whereas 29.3 and 24.7 km² of grassland and shrubs land were converted into cultivated land. As a result, the maximum NDVI and NDWI values were decreased between 1991 and 2021. To minimize the rapid loss of wetland and water bodies in the study area, proper land use planning and environmental education should be promoted.

Cadmium (Cd) and arsenic (As) are both potentially toxic heavy metals (HMs) found ubiquitously in the environment. These HMs are prevalent in soil due to natural occurrences or anthropogenic activities. Co-contamination of Cd and As in soil is a major concern for plant and human health as well as ecosystem sustainability due to their hazardous properties. Therefore, a global imperative is developing improved technologies for managing and remediating soil co-contaminated with Cd and As. One effective solution for remediating Cd/As co-contaminated soil involves the utilization of natural biopolymers and biostimulants, such as chitosan (CS). CS offers distinct advantages, including its ready availability, biodegradability, biocompatibility, environmental friendliness, and cost-effectiveness when compared to alternative adsorbents. The adsorption mechanism of CS and CS-based adsorbents for Cd and As primarily relies on electrostatic attraction, complexation, and ion exchange. This review article provides a comprehensive overview of Cd and As co-contamination in soil, elucidating their sources, distribution patterns, exposure pathways, and the prospective remediation approaches employing CS biostimulants and CS-based adsorbents. Furthermore, it summarizes recent studies investigating the adsorption of Cd/As by CS, the factors influencing the adsorption efficiency and the challenges associated with the utilization of CS and CS-based adsorbents. In conclusion, the review underscores the need for further research to concurrently remediate Cd and As co-contaminated soil, enhance the adsorption efficiency of CS and CS-based composites, and broaden their practical applicability for remediating co-contaminated soils.

GRAPHICAL ABSTRACT

Climate and land use/cover (LULC) changes are essential factors that influence hydrological regimes by altering the groundwater recharge and river flow. This study investigated the separate and combined impact of climate and LULC changes on streamflow. The Soil and Water Assessment Tool (SWAT) was used to simulate streamflow under near-term (2021–2050) and mid-term (2051–2080) period against 1985 to 2015 baseline period. The Cellular Automata (CA)-Markov chain model was used to predict the future LULC change. The three-ensemble average of regional climate models (CCLM4.8, RACMO22T, EC-EARTH) under RCP 4.5 and RCP 8.5 emission scenarios were applied for future climate projection. The LULC predictions between 2035 and 2055 showed an increase in agricultural land, grassland, settlement areas and woodlands by 44.02%, 30.35%, 69.2%, and 55.05%, respectively, while forest and scrub/bush lands showed a decrease by decrease by 21.53% and 11.08%, respectively. The annual, wet, and dry seasons rainfall projections increased by 0.13%, 0.02%, and 0.85% respectively, during the near term period under RCP 4.5 scenarios. Overall, the annual, wet, and dry season rainfall projections showed slightly increasing tendency. The temperature projection consistently indicated a warmer future with the highest mean annual projected temperature being 2.0°C under high emission scenario during the midterm period. The projected streamflow under the combined impact of climate and LULC changes will increase by up to 8.72% in wet seasons and by up to 6.62% in dry seasons during the near-term period under RCP4.5 scenarios. Similarly, the projected mean annual streamflow will increase by up to 8.13%. The annual, wet and dry season’s streamflow projections showed a consistent increase during both near and midterm periods under both climate scenarios. Understanding the future response of streamflow under climate and LULC changes is crucial to plan adaptation options for water resources management under future warming condition.

Rainfed agriculture in Ethiopia has failed to produce enough food, to achieve the increasing demand for food. Pinpointing the appropriate site for rainwater harvesting (RWH) have a substantial contribution to increasing the available water and enhancing agricultural productivity. The current study related to the identification of the potential RWH sites was conducted at the Chacha watershed central highlands of Ethiopia which is endowed with rugged topography. The Geographic Information System with Analytical Hierarchy Process was used to generate the different maps for identifying appropriate sites for RWH. In this study, 11 factors that determine the RWH locations including slope, soil texture, runoff depth, land cover type, annual average rainfall, drainage density, lineament intensity, hydrologic soil group, antecedent moisture content, and distance to the roads were considered. The overall analyzed result shows that 10.50%, 71.10%, 17.90%, and 0.50% of the areas were found under highly, moderately, marginally suitable, and unsuitable areas for RWH, respectively. The RWH site selection was found highly dependent on a slope, soil texture, and runoff depth; moderately dependent on drainage density, annual average rainfall, and land use land cover; but less dependent on the other factors. The highly suitable areas for rainwater harvesting expansion are lands having a flat topography with a soil textural class of high-water holding capacity that can produce high runoff depth. The application of this study could be a baseline for planners and decision-makers and support any strategy adoption for appropriate RWH site selection.

Rhizodeposition, as transported from photosynthates and exudated in soils via fine roots, is the pivot linking above- and belowground carbon (C) cycling pathways. Meanwhile, rhizodeposit C serves as “currency” for plant nutrient acquisition because of its critical roles in priming soil microorganisms, maintaining plant-mycorrhizal symbionts, and elongating plant roots. Therefore, a conceptual framework integrating knowledge on the biogeochemical fate of rhizodeposit C can help understand plant nutrient economics and soil C sink function. However, it still remains a great challenge to efficiently delineate the dynamics of rhizodeposit C in soils. In the framework, we present the possible stabilization pathways of rhizodeposit C via formation of mineral-associated organic matter (MAOM) or encapsulation by microaggregates. We further propose that continuous and pulse ¹³CO₂ labeling are powerful techniques to track the fate of rhizodeposit C and to quantify how much C could eventually be sequestrated in soils as the component of MAOM or microaggregates. This framework would provide future research possibilities to better optimize plant C allocation and productivity and preserve soil C stocks.

Landslides are a geological hazard commonly induced by rainfall, earthquakes, deforestation, or human activity causing loss of human life every year specially on highlands or mountain slopes with serious impacts that threaten communities and its infrastructure. The incidence and recurrence of landslides are conditioned by several aspects related to soil properties, geological structure, climatic conditions, soil cover, and water flow. Precisely, Colombia is one of the most affected by this type of natural hazard, as well as by floods, since they are the natural phenomena that bring with them the most severe risks for communities. In this work, we articulated the statistical approach of the landslide conditioning factors, Machine Learning Algorithms (MLA), and Geographic Information System (GIS), evaluating a flexible and agile methodology to estimate the landslide susceptibility defining areas prone to the landslide occurrence. The MLA were validated in a case study in the “La Liboriana” River basin, located in the Municipality of Salgar in the Colombian mountains Andes where Landslide Susceptibility Maps (LSMs) were obtained. The obtained MLA results hold immense potential in the field of regional landslide mapping, facilitating the development of effective strategies aimed at minimizing the devastating impacts on human lives, infrastructure, and the natural environment. By leveraging these findings, proactive measures can be devised to safeguard vulnerable areas, mitigate risks, and ensure the safety and well-being of communities. Seven supervised MLA were employed, two regression algorithms (Logistic) and five decision tree algorithms (Recursive Partitioning and Regression Trees [RPART], Conditional Inference Trees [CTREE], Random Forest [RF], Ranger, and Extreme Gradient Boosting Algorithm [XGBoost]). The LSMs were produced for each MLA. Considering different performance metrics, the RF model yields the best classification accuracy with an area under receiver operating characteristic (ROC) curve of 95% and 90% of accuracy, providing the most representative results. Finally, the contribution of each landslide conditioning factor on predictions with RF model is explained using the SHAP method.

In areas with scarce water resources, it is so important to analyze the connection between the different elements of a river basin and the water collected by the basin’s reservoir, to determine and predict the spatial and temporal variability of water on it. In this paper, we use the basic principles of hydrological modelling to develop a model for the exploitation of rainfall in reservoir basins in the province of Malaga, Spain. The monthly water input data of the seven reservoirs in the province of Malaga, provided by the Hidrosur Network of the Automatic Hydrological Information System (SAIH), as well as the precipitation and daily temperature of the stations of the State Meteorological Agency (AEMET) associated with the basins of each of these reservoirs were used. We assume that the entrance to a reservoir in a given month must depend on the precipitation produced in its watershed (both the amount of rain and the intensity with which it fell), the precipitation collected from the previous months (and the way in which it was produced) and the evapotranspiration produced during that period. For each reservoir, we propose a model with nine parameters to simulate the arrival of rainfall to the reservoir, covering aspects from the amount and intensity of rain, past and present, to the level of evapotranspiration on a given area for a given date. These nine parameters are optimally adjusted through an artificial intelligence algorithm to maximize the correlation between real and simulated contributions. The results show how this model, adjusted for each reservoir, will let us predict how changes in the rainfall and temperature patterns, predicted, for example, by the IPCC models, will affect the future water levels at the studied reservoirs.

Sorghum has an enormous role in the economy of sorghum-growing nations. Supplying a precise amount of water to a crop based on crop needs is the main agenda in implementing water-saving agriculture. Non-weighing type lysimeters were used to determine actual crop evapotranspiration and crop coefficient of sorghum at the experimental farm of Melkassa Agricultural Research Center situated in the semi-arid area of Ethiopia. Soil-water balance approaches were applied to obtain actual crop evapotranspiration, while the Penman-Monteith technique was used to determine reference evapotranspiration. Growth stages-wise crop coefficient was computed as a ratio of actual crop evapotranspiration to reference evapotranspiration. The total seasonal sorghum actual crop evapotranspiration during the 2017 and 2018 experimental years was 358.6 and 377.54 mm, respectively. The 2 years average sorghum actual crop evapotranspiration was 368.07 mm. The mean locally developed actual crop coefficient values of 0.55, 1.15, and 0.59 were observed for the initial, mid, and end-season, respectively. The FAO-adjusted crop coefficient values for mid and end-season were 1.01 and 0.52, respectively. The developed Kc values considerably differed from the FAO-adjusted Kc values. So, the determination of actual crop evapotranspiration and crop coefficient for crop growth at local climate conditions is vital for decision-making concerning water management in the area where irrigation is practiced.

This study is devoted to heavy metal soil migration to coltsfoot in urban pollution of Tyumen city. Soil and plant samples were collected in the summer of 2017 to 2020 at the control site, highway, engine-building, oil refinery, battery manufacturing, and metallurgical plants. Heavy metals (Cu, Zn, Fe, Mn, Pb, Cd, Ni, Co, and Cr) mobile and acid-soluble forms in soils, and metals concentration in plants were analyzed by atomic absorption and atomic emission spectroscopy. Metals concentration in soils of urban area exceeded the control by 1.1 to 20 times. Relative accumulation of metals decreased in the order: Pb > Cu > Zn > Ni > Cr > Fe > Co > Mn > Cd. Heavy metals mobility in soils decreased in the order: Cd > Mn > Pb > Zn > Ni = Cu > Co > Cr > Fe. Coltsfoot metal accumulation changed in the order: Fe > Zn = Mn > Pb > Cu > Cr > Co > Ni > Cd. The highest contamination for most of the metals was at the metallurgical plant, while Ni and Co concentrations were maximum at the oil refinery. Content of Cu, Zn, Fe, Cd, Ni, and Co in coltsfoot correlated with a concentration in soils. Bioconcentration factor showed the following metal bioavailability: Cu > Zn > Cd > Pb > Ni > Mn > Cr > Co > Fe. Heavy metal accumulation in coltsfoot should be taken into account during sanitary control of herb drugs based on this plant.

Cover crops are a valuable tool for improving resources use, soil health, and productivity. However, the effects of intercropping cover crops as live mulches with cash crops can vary depending on the species, management practices, and environmental conditions. This study reviewed the literature on cover crop intercropping and identified key factors to consider for improved plant productivity and resources use when managing these cropping systems. Science Direct, Scopus, and Google Scholar were used to search for literature on managing cover crop intercropping as live mulches. Research has shown that annual cover crops are typically used in annual field crop systems, while perennial cover crops are typically used in orchards and vineyards. The effects of intercropping annual or perennial cover crops in vineyards, orchards, and field crop systems can vary from positive to negative, depending on the climate, soil, management, and production system. Therefore, there is no one-size-fits-all management strategy. However, there are some key factors that should be considered when managing cover crops, such as: compatibility, intercropping time, planting density, and termination time. The benefits of appropriate cover crop management include: extended growing season, increased soil fertility, resource use optimization, and increased biomass productivity. Cover crop intercropping can be a successful way to improve resource use, soil health and productivity, but it is important to carefully consider the specific crop and management practices to ensure success. Therefore, future research should optimize cover crop intercropping time and planting density in maize-based rainwater harvesting systems on productivity and resource use.

Even when the influence of climate on the geomorphological dynamics of mountain areas is well known, the ground and near-rock surface air thermal regimes of the highest altitude Cantabrian massifs still being poorly understood. This study, based on the examination of the thermal data obtained through the use of air and soil temperature dataloggers, aims to characterize the thermal regime of one of the most representative high mountain massifs of the Cantabrian Mountains: the Western Massif of the Picos de Europa. Results show the severe climatic conditions that prevail in the highest areas, where the snow cover lasts for 8 months on average, exerting an important insulating role of the soil. Thus, except on the uncovered rocky walls, the number of freeze-thaw cycles per year is low (0–16), with these cycles having a short duration and a low thermal amplitude. Significantly differences on annual thermal regimes have been confirmed; with two main phases (continued thaw phase and isothermal phase) and two minor transition phases at the ground, and only two main phases in near-rock surfaces (continued thaw phase and phase with a high number of FTCs).

The emergence of polycyclic aromatic hydrocarbons (PAHs) from a variety of natural and anthropogenic sources, such as coal gasification and liquefaction plants, coke and aluminum production, catalytic cracking towers, and motor vehicle exhaust, among others, results in significant soil pollution, and a threat to human health, igniting a surge of interest in advanced research. Even though the cleanup of PAHs-contaminated areas received a great consideration. In the last decade, nanotechnology has exploded in popularity as a result of several unique properties of nanomaterials, and remediation is no exception. Thus, nano-enhanced bioremediation reported to act as a viable and effective strategy for PAHs remediation. Further, the integration of nano-enabled materials with microorganisms emerged as a promising biodegradation approach for PAHs remediation. As a result, the focus of this mini review is on depicting the possible roles of various nanomaterials in decontaminating PAHs as a green strategy by boosting the efficacy of microbial functionality, and mechanism of nanoparticles-microbes interaction in PAHs degradation. The future perspective of nano-enhanced microbial remediation of PAHs in realistic environments are also discussed.

Integrating water, energy, and food (WEF) systems can generate synergies and help Eastern Mediterranean countries solve climate change-related concerns. The WEF nexus strategy provides a comprehensive and integrated approach to solving the issues faced by climate change and a roadmap toward sustainable water, energy, and food systems. The significance of understanding the WEF nexus in the context of climate change cannot be emphasized, and further study and implementation are required to reach its full potential. In this study, we investigated the available options for decision-makers to combat climate change; for example, renewable energy is seen as a critical component for assisting the water, energy, and food sectors in addressing the issues faced by climate change. Renewable energy may supply clean, dependable, and sustainable electricity for water treatment and distribution systems, agricultural and food processing enterprises, and energy-intensive businesses. In addition, for the region’s sustainable development, cooperation between Eastern Mediterranean countries in addressing the issues of climate change and the WEF nexus is crucial. Promoting cross-border commerce and establishing regional frameworks and initiatives can play a vital role in tackling these difficulties and assuring the region’s sustainable future.

Several Arab countries face numerous environmental problems in addition to climate change, desertification, and water crisis. Multiple issues related to water and energy need to be resolved. In this paper, we examine the most important topics to be studied, and the research conducted to elucidate the importance of the water problem in the Arab region, including the gap between increased demand and a lack of resources. Water problems include leakage, pollution, and depletion of water resources. We also focus on climate change and the role of young people, software, educational institutions, and training centers in achieving water security and sustainable development objectives. The paper also investigates the idea of water harvesting, the relationship between water, food security, and energy, the role of stakeholders, and good governance in solving the water crisis by understanding the problems and framing research within a multi-year work program with financial, legislative, and scientific support. Providing incentives and the necessary research structure to coordinate all sectors and organizations concerned with water is also essential.

The impact of increasing air pollution on human health and the environment is a major concern worldwide. Exposure to air pollution is one of the leading risk factors and substantially contributes to morbidity and premature mortality. This review paper aims to examine the exposure of major air pollutants (i.e., particulate matter, sulfur dioxide, oxides of nitrogen, carbon monoxide) and its association with respiratory, cardiovascular, reproductive, and genotoxic adverse health outcomes that can cause DNA damage leading to genetic mutations. The study emphasized how a better understanding of source-receptor relationships and exposure assessment methodologies can support effective air quality management planning. Hence, there is a need to augment various exposure indicators (spatial modeling, personal/area monitoring, emphasizing central/rural site measurements, etc.) to generate reliable surrogates for informed decision-making. The critical drivers of anthropogenic interference for air pollution remain urbanization, growing vehicle use, and industrialization. This requires innovative approaches, such as energy-efficient and technologically sustainable solutions to gradually replace conventional fossil fuel from primary energy mix with renewable energy. It holds the key to meet future energy challenges and minimizing air pollution emissions. Further, there is an urgent need to frame effective public policy with graded mitigation actions to reduce the adverse impact of air pollution on human health and the environment.

Restinga forests and open scrubby formations establish on sandy well-drained soils alongside the Brazilian coastline. Restinga plants are exposed to extreme conditions and vegetation types are mainly structured by species access to groundwater. But to date, no systematic evaluations have been done in order to characterize soil microclimatic conditions and understand how they are associated with variations in climatic drivers. We evaluated hourly soil moisture and temperature along 84 days at Restinga Seasonal Dry Forest (SDF), sparse (Open Clusia Scrubs—OCS), and dense (Open Ericacea Scrubs—OES) tickets at Restinga de Jurubatiba National Park, at Rio de Janeiro state (Brazil). Due to distinctions on physical structure and access to groundwater between plant formations, we expected higher daily soil moisture and lower daily moisture and temperature variations on forests than on open vegetated areas. Daily soil moisture was higher, respectively, on SDF, OES, and OCS, whereas soil moisture and temperature variability presented the opposite trend (SDF < OES < OCS), supporting our hypotheses. Daily soil temperature dynamics are quite well predicted by solar radiation incidence patterns, whereas daily soil moisture is mainly regulated by precipitation at OCS, an interaction of precipitation and temperature at OES and delayed effects of precipitation at SDF. Our results corroborate our expectations that forests are more effective in buffering both air temperature and precipitation effects on soil conditions than open vegetated areas. They also indicate that soil moisture and temperature conditions are important aspects differentiating Restinga vegetation types.

Understanding how watersheds respond to ecological changes and how LULC alteration affects watershed hydrology is crucial for water and soil resource management. LULC changes in the Ajora-Woybo watershed, Ethiopia, have momentously affected the water and soil resources. The researchers aimed to see how LULC changes affect hydrological components (HCs) and sediment yield (SED) in the watershed, both historically and in the future. The Soil and Water Assessment Tool (SWAT2012) and Partial Least Squares Regression (PLSR) models were used to investigate the contribution of each of the LULC classes to achieve the goal. The findings revealed a continual growth of cultivated land, built-up areas, and bare land, and a retreat of shrub land and forest land during the 2000 to 2020 periods, which is expected to continue in the 2035 and 2050 periods. Changes in LULC that happened over the historical era increased yearly surface runoff (23.5%), water yield (5.7%), and sediment yield (23.5%). On the other hand, the observed modifications have reduced lateral flow (12.8%) and groundwater flow (10.9%). Except for the 2020 LULC period, evapotranspiration decreased during the studied years. The future impacts of LULC states are predicted to increase in line with the historical trend. The PLSR results showed that cultivated land and built-up areas had a positive association with surface runoff and sediment yield, but shrub land and forest land had a negative correlation. This highlights the importance of controlling the LULC change as soon as possible to maintain long-term watershed stability.

Hydropower is currently one of the leading renewable energy sources in developing countries. Despite the benefits that it can provide, it also triggers significant environmental impacts, such as changes in the reservoirs’ water quality. In quantifying those changes, dissolved oxygen (DO) is used as one of the water quality indicators and is the most used variable to quantify water quality and analyze water pollution. This paper aims to establish a relationship between water quality and hydrometeorological variables in tropical reservoirs to better estimate dissolved oxygen. Univariate and multivariate techniques were used to analyze temporal and spatial changes in watersheds to better select vital variables for the forecast model, such as Vector Autoregression (VAR). The results show that, for all monitoring stations, the water quality variables associated with the DO process are COD, BOD, and PO₄. Likewise, precipitation and flow discharge were the hydrometeorological parameters that had the most significant impact on DO. Also, the principal component analysis (PCA) allowed us to identify that the strength of the relationships between water quality and hydrometeorology changes depending on the location of the monitoring site. Finally, the implementation of a VAR model showed good performance metrics for dissolved oxygen predictions based on all analyses.

ABSTRACT:Air pollutants generated as a result of operations of landfill sites pose a threat not only the environment but also to human life. This work focuses on comprehensive review of atmospheric air pollutants around landfill sites with a view of identifying areas where future studies can be conducted. Environmental and health effects of air pollutants within the vicinity of landfill sites and the ways of minimizing the level of the air pollutants were presented. Previous works carried out by scholars for the past two decades were critically examined. Mathematical models for prediction of gaseous pollutants for landfill sites and assessment of human health risk due of inhalation of poisonous gases from landfill sites were discussed. Amongst conclusions made were: (1) Further studies on health impacts of particulate matters (PMs) within the vicinity of landfill sites should focus on low-income countries (LIC) especially in Nigeria which has been perceived as the capital poverty of the world. (2) Developing countries have not been practicing Circular Municipal Solid Waste Management System (CMSW) due to some militating factors hence further works should look into how the militating factors can be surmounted and provide way forward for the implementation of CMSW in developing countries. (3) More works still need to be conducted especially in temperate region to mechanistically explain the positive correlation between PMs and Coronavirus disease. (4) Future works should dive into the cost and economic implications of assessing atmospheric air pollutants within the vicinity of landfill sites for policy making decisions.

At the request of SAGE Publishing, the following article has been retracted:

At the request of Sage Publishing, the following article is retracted: