Filters
Quantifying the impacts of spatiotemporal land use and land cover changes on soil loss across agroecologies and slope categories using GIS and RUSLE model in Zoa watershed, southwest Ethiopia
Abstract Background Soil erosion in Ethiopian highlands is highly consistent with land use/land cover (LULC) changes that are associated with deforestation and a decline in biodiversity. However, identifying soil erosion-prone areas and quantifying soil loss in rugged terrains and various agroecologies due to LULC changes have not been dedicated to scientific studies. Therefore, we quantified the impacts of spatiotemporal LULC changes on soil loss across agroecologies and slope categories using GIS and RUSLE model from 1985 to 2021 in Zoa watershed, southwest Ethiopia. Moreover, prioritizing erosion severity risks at sub-watersheds and quantifying temporal sediment yield is essential for better conservation planning. Landsat images, rainfall, Digital Elevation Model, and soil data were obtained from field observations and secondary sources. Results Bareland and farmland have been expanding at the expense of other land use types. The annual soil loss in the watershed ranged from 0 to 113.21 t ha−1 year−1, 0 to 163.16 t ha−1 year−1, and 0 to 194.58 $$\mathrm{t}\,{\mathrm{ha}}^{-1}\,{\mathrm{year}}^{-1}$$ t ha - 1 year - 1 with a mean annual soil loss of 21.07, 29.35 and 40.93 t ha−1 year−1 in 1985, 2000, and 2021, respectively. Among LULC classes, the highest soil loss was generated from bareland (31.73 $$\mathrm{t }\,{\mathrm{ha}}^{-1}\,{\mathrm{year}}^{-1}$$ t ha - 1 year - 1 ) and farmland (27.08 t ha−1 year−1 ) in 1985 later upsurged to 35.52 $$\mathrm{t }\,{\mathrm{ha}}^{-1}\,{\mathrm{year}}^{-1}$$ t ha - 1 year - 1 and 59.91 t ha−1 year−1 in 2021, respectively, due to the maximum susceptibility of soil erosion risks from unprotected surfaces. The results also revealed that the lowland agroecology generated the highest mean soil loss of 24.05 $$\mathrm{t }\,{\mathrm{ha}}^{-1}\,{\mathrm{year}}^{-1}$$ t ha - 1 year - 1 in 1985, 39.74 t ha−1 year−1 in 2000, and increased to 57.55 $$\mathrm{t }\,{\mathrm{ha}}^{-1}\,{\mathrm{year}}^{-1}$$ t ha - 1 year - 1 in 2021. Considering the slope categories, the highest and most excruciating soil loss was engendered from steep (35.55–60.78 t ha–1 year–1) and very steep (52.48–72.69 $$\mathrm{t }\,{\mathrm{ha}}^{-1}\,{\mathrm{year}}^{-1}$$ t ha - 1 year - 1 ) slope terrains during 1985–2021. The northwestern part of the watershed is the most erosion-prone area which is now expanding to the central and western parts of the watershed. The sediment yield increased at the fastest rate at the watershed outlet, from 39.3% in 1985 to 94.26% in 2021. Conclusions The results of this study indicated that the conversion of other LULC categories into farmland was the most detrimental to a watershed in terms of soil loss, which necessitates the implementation of appropriate soil and water conservation measures with effective design by considering spatial variability to reduce soil erosion hazards.
Health Risk of Heavy Metals Related to Consumption of Vegetables in Areas of Industrial Impact in the Republic of Kazakhstan—Case Study for Oskemen
Among various heavy metal sources the metallurgic industry is the most threatening because emitted metals presented are the chemical forms in which metals are found in soil are more bioavailable and thus very easily are introduced into the environment and spread in both soils and plants. In this study such a situation is presented and the potential negative effect of emitted metals on soil and vegetables is estimated. Therefore, the following indicators were used: bioconcentration factors calculated for the total amount of metals (BCF) as well as daily intake of metal (DIM) and health risk index (HRI). Analyzed soils and vegetables originated from allotment gardens located at different distances from local industrial plants. The greatest amounts of metals in investigated materials (soils and plants) were found for the industrial zone and the lowest for samples representing the suburban zone. Among the analyzed metals Zn showed the highest (223.94–2645.13 mg·kg−1 for soils and 9.14–49.28 mg·kg−1 for plants), and Cd the lowest levels (1.77–15.2 mg·kg−1 for soils and 0.05–0.46 mg·kg−1 for plants). Regardless of the metal, the lowest BCF values were calculated for plants from the industrial zone and the highest from the urban site. Generally, BCF values calculated for vegetables were low and comparable for carrots, tomatoes, and cabbage. BCF values obtained for beetroots were higher in comparison to other vegetables. Regardless of plants, DIM values for Cd and Pb were low and comparable. DIM values for Cu and Zn were higher, but simultaneously strongly differentiated depending on the analyzed vegetables. A similar tendency was found in the case of HRI. The highest values were recorded for Cu and Zn in tomatoes. Regardless of the individual metals, the calculated values for DIM and HRI indices increased in the following sequence: beetroot < cabbage < carrot < tomato. The Zn and Cu contents in the studied types of vegetables do not exceed the maximum permissible levels recommended by WHO/FAO. In contrast, Pb concentrations were higher than the imposed standards in all the analyzed vegetable samples. On the basis of obtained DIM and HRI indices, consumption of vegetables cultivated in industrial areas should be restricted due to health risks related to heavy metals contained in plants.
Impacts of land use and cover changes on ecosystem service values from 1992 to 2052 in Gena District, Southwest Ethiopia
Impacts of land use and land cover changes on carbon stocks (1992–2052) Using geospatial technologies in Gena district, Southwest Ethiopia
Determination of Polycyclic Aromatic Hydrocarbons (PAHS) in Sewage Sludge and Compost by Dispersive Solid-Phase Microextraction (SPME) and Ultra-High Performance Liquid Chromatography (UHPLC) with Diode Array Detection (DAD)
The Application of Sewage Sludge-Derived Compost or Biochar as a Nature-Based Solution (NBS) for Healthier Soil
Nanoparticles for Sustainable Agriculture: Assessment of Benefits and Risks
Nanotechnology is rapidly emerging as a transformative force in agriculture, offering innovative solutions to support sustainable crop production. This review examines the interactions between nanoparticles (NPs) and plants, elucidating the underlying mechanisms that govern NP uptake, translocation, and interactions at the cellular level. We explore how NPs influence key physiological processes and modulate plant defense responses to both biotic and abiotic stresses, highlighting their potential for enhancing stress resistance. The diverse applications of NPs in agriculture are also comprehensively surveyed, encompassing targeted delivery of nutrients, enhanced biocontrol of phytopathogens, and engineering improved tolerance to environmental extremes. We also address the broader environmental and socioeconomic implications of the widespread use of NPs in agriculture, critically evaluating their ecotoxicity, impacts on biodiversity, and the associated economic costs and benefits. Finally, we offer a perspective on future directions for research, including emerging trends in NPs synthesis and characterization, challenges to sustainable implementation, and the prospects for large-scale deployment of nanotechnology-enabled agricultural solutions. This review provides a rigorous and balanced assessment of the potential of nanotechnology to revolutionize agricultural practices while acknowledging the need for responsible innovation and risk mitigation.
Rate of Microelement Quantitative Changes during the Composting of Sewage Sludge with Various Bulking Agents
The composting of sewage sludge (SS) with structure-forming additives is a popular and inexpensive method for the management of biodegradable waste. During this process, a number of transformations of organic matter and nutrients occur. This study presents the rates and directions of quantitative changes in Cu, Zn, and Ni during the composting of various mixtures. The following substances were used for preparing compost mixtures: SS, sawdust, straw, and bark. These substances were mixed together in appropriate proportions as follows: C1: 45% SS + 50% sawdust + 5% straw; C2: 45% SS + 50% bark+ 5% straw; and C3: 45% SS + 35% bark + 15% sawdust + 5% straw. Single (DTPA solution) and sequential extraction methods (BCR protocol) were used for microelement mobility assessment. Compost valorization was performed in each individual composting phase. The chain relative increment analysis was used for such assessment. Additionally, the potential metal pollution in the composts was evaluated by applying the following indices: the pollutant accumulation index (PAI), heavy metal enrichment index (HMEI), and heavy metal pollution load index (HMPLI). During composting, generally, the amounts of Ni, Cu, and Zn increased in the various extracted combinations, which was independent of their susceptibility to decomposition. Despite of this, the tested composts should be considered as a source of slowly available microelements for plants. The most intense quantitative changes in metals occurred in the thermophilic phase, and the weakest changes occurred in the cooling phase. At the same time, the calculated indices indicated a lack of contamination of the composts with the analyzed metals, emphasizing their environmental safety and lack of negative impact. The bulking agents used for composting with SS did not significantly influence the intensity of the quantitative changes in the tested metals.
Quantitative Distribution and Contamination Risk Assessment of Cu and Zn in Municipal Sewage Sludge
One of the methods of managing sewage sludge (SS) is its soil application. This possibility is promoted by the chemical composition rich in organic matter and nutrients. However, heavy metal contents in SS must meet respective permissible limits. Among the heavy metals in SS, Cu and Zn are found in the largest amount; thus, this study focuses on these elements. The main aim of the study is to investigate the quantitative distribution of metals in sequentially separated fractions of sewage sludge. Additionally, the potential risk of environmental contamination with heavy metals was assessed in the case of SS application for agricultural purposes. The relevant analyses were conducted on four different examples of municipal SS. Based on the total amounts as well as those determined in the SS fractions, the following indices were calculated: Igeo (geoaccumulation index), ICF, (individual contamination factor), and RAC (risk assessment code). The use of data from the sequential analysis as well as the calculated indices made it possible to assess the usefulness of SS in practice in terms of potential introduction of Cu and Zn into the environment with the sludge dose. It was found that total Cu (Cutot) and Zn (Zntot) did not exceed the permissible limits binding within respective Polish and international regulations. Regardless of the years of study and the analyzed SS, Cutot ranged from 260.9 to 393.5 mg·kg−1, and Zntot from 475.5 to 1153.1 mg·kg−1. The amounts of Cu and Zn were predominantly reducible (bound to iron and manganese hydroxides, Fr. II) and oxidizable complexes (bound to organic matter and sulfides, Fr. III). The average amounts of Cu in Fr. II ranged from 149.4 to 172.4 mg·kg−1, while those of Zn in Fr. II ranged from 370.9 to 754.6 mg·kg−1. Cu amounts in Fr. III were from 160.9 to 183 mg·kg−1 and Zn amounts in Fr. III were from 104.9 to 171.9 mg·kg−1. Total content of metals as well as TOC values strongly determined the quantitative level of both elements in the SS fractions. Generally, with the increase in the total amount of metals, their levels in the sludge fractions increased. In turn, the increase in TOC resulted in a decrease in the amounts of Cu and Zn in the sludge fractions. Calculated Igeo and ICF ratios showed high and very high SS contamination with Cu and Zn. Igeo values for Cu, regardless of the year of study and sludge sample, that ranged from 4.62 to 5.43 and for Zn from 3.41 to 4.86. At the same time, the ICF values for Cu ranged from 8.59–23.04, and for Zn 15.42–44.47. The RAC values indicated a low (Cu) and medium (Zn) risk of using SS in terms of the potential metal availability in the environment. The RAC values ranged from 1.46 to 4.40% for Cu and from 9.63 to 23.13% for Zn.
Mint Plants (Mentha) as a Promising Source of Biologically Active Substances to Combat Hidden Hunger
Hidden hunger, also known as micronutrient deficiency, is a form of undernutrition, which is exacerbated when food security is fragile. However, the amount of phytonutrients in the diet can be increased by using underutilized species, such as fresh mint greens (Mentha). These plants have a high biological value due to the high content of biologically active substances. Plants of the genus Mentha, however, differ significantly in their chemical composition and, thus, nutritional value. The main objective of this study was to evaluate the content of phytonutrients in different Ukrainian species of mint: peppermint (Mentha piperita), horsemint (Mentha longifolia L.), silver-leaved horsemint (Mentha longifolia S.), and spearmint (Mentha spicata L.), and to determine their stability after drying and freezing. After studying the chemical composition of fresh, dried, and frozen plants of these species, it was established that Ukrainian mint species offer a robust set of phytonutrients and can be used as ingredients of the so-called “functional foods.” The biologically active substances in mint are concentrated during drying. Moreover, such raw materials are easily stored and used as an ingredient. However, the losses of ascorbic acid due to drying mint reach 70%; of carotenoids—approximately 10–15%; of chlorophylls—21–38%; and of phenols—19–29%. Peppermint and spearmint were observed to have higher stability of biologically active compounds. As for the freezing, the best stability of the chemical composition was demonstrated by field mint and spearmint samples. Therefore, a targeted selection of mint types and varieties prior to processing will allow preserving maximal preservation of a maximum amount of biologically active substances, increasing the content of phytonutrients in finished products, and preventing the development of hidden hunger.
Quantitative Changes in Selected Soil Health Indices as a Result of Long-Term (23-Year) Cultivation of Winter Wheat in Various Crop Rotations: Case Study for Sandy Soil
Quantitative Changes in Various Nutrient Ratios in Fodder Plants as an Effect of Compost and Fly Ash Application
Despite the popularity of concentrated feed, fodder crops are still important, especially in organic livestock farming. However, this type of feed must meet certain criteria, which are often described using correct nutrient ratios. The research investigates the influence of compost and fly ash on quantitative changes in nutrient ratios determined for lupine and oat cultivated on soil slightly contaminated with Cu. A pot experiment was conducted on medium soil. Immobilizing agents (compost and fly ash) were applied at the dose of 40 t per ha. Plant materials were subjected to chemical analyses to assess their macronutrient content and, based on these data, mutual proportions of individual nutrients were calculated as mass ratios of K:Mg, K:Na, Ca:P, Ca:Mg, K:(Ca+Mg) and (K+Na):(Ca+Mg). Changes in ratio values were visualized using statistical tools, i.e., Anova, correlation coefficients and dendrograms. It was found that immobilizing agents constituted a source of the chosen nutrients because their amounts in plants grown on the soil fertilized with either compost or fly ash compost were significantly higher than in the control plants. This phenomenon was especially visible with regard to Ca and Mg for both lupine and oat. It should be emphasized here that the effect of compost or fly ash on the content of Ca and K in plants was comparable. In general, the application of compost contributed to higher values of the analyzed nutrients in both plants. The control and fertilized fly ash plants were characterized by lower values of nutrient ratios. The expected optimal value range of 2–3:1 was determined only for Ca:Mg, which was found in both lupine and oats. The proper values of K:Mg (2–6:1) were found only in the case of fodder plants cultivated on soil amended with compost.
Assessment of lupine seed fodder quality depending on the variety and tillage system used as factors for sustainable agriculture
Current Trends in Sustainable Sewage Sludge Management—A Case Study for Poznań County, Poland
The formation of sewage sludge (SS) is directly related to the number of people served by municipal wastewater treatment plants (WWTPs), while it is also impacted by increasingly upgraded sewage treatment technologies used in such installations. The presence of SS in our environment raises a number of concerns regarding its proper and sustainable management. In practice, the choice of a specific SS disposal method is determined by a number of factors and, as this research has shown, it may vary significantly both on the national and regional scale. This study analyzed this phenomenon in relation to Poznań County, located in the Wielkopolskie province, Poland. As part of this study, the SS chemical composition was assessed based on data obtained directly from local municipal WWTPs over the course of several years (the last 7 years). The currently used SS management methods were analyzed in terms of SS chemical composition. Moreover, in view of the importance of public involvement in decision-making processes related to sustainable management of SS, an original survey was developed to assess local residents’ knowledge concerning SS management in Poznań County. Based on the obtained data, it was found that the generated SS, constituting a form of fertilizer, was primarily used for agricultural and reclamation purposes (over 41% of total SS mass in the case of Poznań County). It is facilitated by the chemical composition of this waste, characterized by high contents of organic matter (380–730.3 g·kg−1), nitrogen (13.3–78 g·kg−1), and calcium (9.5–350 g·kg−1), while the amounts of heavy metals were within the permissible ranges. A survey of the local community revealed that although respondents recognized and could accurately identify SS as a waste, their knowledge concerning harmfulness of this waste and its management was fragmentary. Regardless of the age of the respondents, 48 to 66% of them had no opinion concerning problems related to SS in their area. The youngest people (aged 18–25) showed the lowest level of knowledge on SS and its management. People with elementary education were the least knowledgeable about sewage sludge management. Regardless of the above, a majority of respondents (28–56% for different age groups and 7–18% for various educational backgrounds) were convinced of the validity of agricultural SS use. To sum up, research on sewage sludge is an indispensable element of activities aimed at sustainable development, combining aspects of environmental protection, circular economy, and social awareness and acceptance. Additionally, the study results indicated the need for social education to increase environmental awareness and co-responsibility for SS management.