Agricultural Use Research Articles

Assessment of the benefits and risks of sewage sludge application as soil amendment for agriculture in Eswatini

Sewage sludge is an important soil conditioner, and source of nutrients with a potential for use in agriculture. However, such benefit needs to be weighed against the risks due to the presence of heavy metals, and other substances that may endanger human health, plants, soil and the ecosystem. This research had the objective of evaluating the agricultural potential of sewage sludge together with the risks that may be present in use. Samples of sewage sludge from seven wastewater treatment plants in Eswatini were analyzed for selected physical and chemical parameters, and heavy metal concentrations using commonly established laboratory procedures. The analysis results indicated that, sludge samples exhibited high organic matter content, cation exchange capacity, macro nutrients such as nitrogen and phosphorus and micro nutrients (trace metal elements) needed for plant growth. Anaerobically digested sludge samples showed higher carbon to nitrogen ratio because of biomass loss in the form of methane and carbon dioxide. The heavy metal concentrations are all within safe limits except the sludge from Matsapha area that had levels of chromium, and nickel above regulatory limits. With respect to their heavy metal contents, most of the sludge samples would qualify as Class A sludge ready to be used as organic fertilizer for agriculture without regular monitoring of heavy metals in the soil to which they are applied. The study results indicated the importance of sewage sludge for their agricultural potential through supplementation of both micro and macro nutrients needed for plant growth, for improving the soil properties such as water holding capacity and permeability, through the increase of organic matter content, and retention of nutrients due to the high cation exchange capacity. All these benefits are realized with sewage sludge being a lower cost alternative to commercial fertilizers. Moreover, the low concentration of heavy metals present in the sludge presents lower risk that may arise in the course of utilizing the sludge as agricultural supplement. Key words: Agriculture, fertilizer, heavy metals, nutrient, sewage, sludge, nitrogen, phosphorous

Evaluation of the quality of products from multiple industrial-scale composting treatment facilities for kitchen waste and exploration of influencing factors

The aerobic composting process is extensively utilized to manage kitchen waste. Nonetheless, the variability in the quality of compost derived from engineering practices which significantly hinders its broader industrial application. This work investigated the final products of kitchen waste compost at multiple industrial-scale treatment facilities utilizing three distinct aerobic composting processes in a bid to explore key factors affecting compost quality. The quality evaluation was based on technical parameters like seed germination index (GI), and limiting factors such as heavy metal content. The results showed that most of the compost products failed to meet the established standards, with GI being the primary limiting indicator. Furthermore, maturity assessments suggested that compost with low GI exhibited reduced humification could not be recommended for agricultural use. The investigation delved into the primary determinants of GI, focusing on risk factors such as the oil and salt of kitchen waste, and the microbial community of the humification driving forces. The results indicated that products with low GI had higher oil and salt content and a relatively simple microbial community. A thorough analysis suggested that excessive levels oil and salt were potential influencing factors on GI, as they stimulated the activity of acid-producing bacteria like Lactobacillus, suppressed the activity of humification-promoting bacteria such as Actinomarinales, and influenced the decomposition and humification processes of organic matter and total nitrogen, thereby affecting product quality. The findings provide valuable insights for improving kitchen waste compost products for agricultural applications.

Assessment of Well Location for Agricultural Water Use in Coastal Areas Using OpenGeoSys

The use of groundwater for agriculture and fisheries in South Korea accounts for 53% of the total annual usage and is on the rise. However, the amount of agricultural groundwater available near coastal boundaries is affected by seawater intrusion. Therefore, this study uses numerical simulations to estimate the available amount of agricultural groundwater near coastal boundaries, considering the location and depth of well installations. Increasing the horizontal distance of the well installation from the coastal boundary was demonstrated to reduce salinity intrusion concentration by approximately 20% more than adjusting the depth of well installation. This research is expected to serve as supplementary material that can be utilized when installing agricultural wells in coastal areas in the future.

Classification of surface waters and groundwater in terms of drinking, agriculture, and industry

In this study, samples were collected from Seydoon River, The Alaa River, Galal Duparan Well, and Seyed Behzad Seepage Well near Seydoon River during the water year 2021-2022 for evaluation by the Khuzestan Water and Power Organization. Following laboratory analysis, Schuler and Wilcox diagrams were created using Aqua and Chemistry software to classify and interpret the water from The Seydoon River, The Alaa River, Duparan Well, and Seyyed Behzad Seepage Well. The objective of this study is to assess and comprehend the water quality of the rivers and wells in the region for drinking, industrial, and agricultural purposes. Overall, the groundwater in the area is deemed to be of medium to unsuitable quality for drinking. The well water is are classified as extremely hard. Furthermore, The Seydoon River and The Alaa River exhibit lower hardness levels compared to the groundwater in the region. in accordance with the Wilcox diagram, both surface and groundwater in the area are suitable in sodium absorption ratio for agricultural use, but they do face salinity issues. The water from The Seydoon River is suitable for industrial purposes, while The Seydoon River, The Alaa River, and Seyyed Behzad Seepage Well water is drinkable, and the water from Duparan Well is prone to forming deposits.

Life Cycle Assessment of Microalgal Biomass Valorization from a Wastewater Treatment Process

Abstract Purpose The life cycle assessment (LCA) performed in this work evaluates the potential environmental impacts of an activated-sludge-based wastewater treatment plant (WWTP) coupled with microalgal cultivation, including the algal biomass recovery. The system is compared with the WWTP without algal integration to evaluate the potential benefits derived by the coupling. In addition to more conventional valorization strategies for the algal biomass, a special focus is given to the production of biostimulants, that give the chance to replace some chemical fertilizers. Method Four scenarios are compared. They differ in the algal biomass valorization route: direct use in agriculture (S1), incineration with energy recovery (S2), use in cement plant as an auxiliary fuel (S3), and biostimulants production and use on crops (S4). The environmental impacts of the system are assessed including 16 categories, to comprehensively cover its potential impacts. Results S4 allows for significant impact reductions (compared to the WWTP without algal integration) only when the increase of the nutrient-uptake efficiency of crops is taken into account. Assuming a 5% reduction of fertilizers application, S4 shows an improvement in 14 out of the 16 impact categories. Conversely, when the amount of substituted fertilizers is calculated comparing just the macronutrient content of biostimulants with that of algae, S4 is comparable with S1, S2, and S3, where just four to five impact categories show lower impacts than the WWTP without algal integration. Conclusions The LCA confirms the environmental benefits of biostimulants application on crops, although the modeling approach requires further research as it strongly influences the results.

Bibliometric Studyof Global Research Trends on Agriculture 4.0: Publication Pattern,and Thematic Analysis

The present study examines the research on agriculture 4.0 during 1965 to 2022. Bibliometric approach adopted to analyze the current research trends in Agriculture 4.0. To analyze and visualize the data, MS Excel, R software (Biblioshiny) was utilized. The present study intends to analyse the publication pattern and growth rate of literature in Agriculture 4.0. During this period, 1869 documents have been published by 7,258 authors, and 1040 sources which are considered for the study. The publication pattern was analysed by different bibliometric aspect like chronological contribution of papers, year wise growth of publication, geographical distribution of papers, authorship pattern, author productivity, etc. which provide depth information about publication of pattern of agriculture 4.0. The development of Agriculture 4.0 has grown rapidly over the last decade and despite the growing interest in it, studies are still needed to develop its theory. Agriculture 4.0 is an emerging new technology that is like a revolution in the field of agriculture, by adopting the concept of which agricultural scientists can reach a proper conclusion in the literature. It is necessary to make Agriculture 4.0 more understandable and accessible to farmers. This is an exciting field that gives a new discovery and expansion to agriculture. For the successful use of Agriculture 4.0, it will be necessary to make progress at all levels of crops from specialty crops to traditional crops.

Estimating exploitable groundwater for agricultural use under environmental flow constraints using an integrated SWAT-MODFLOW model

Traditionally, the impact of groundwater abstraction on streamflow and aquifers has been assessed primarily in terms of water availability and depletion, often neglecting critical environmental flow (Eflow) requirements. To address this gap, our study employed an Eflow perspective to evaluate exploitable groundwater for agricultural use at a watershed scale using an integrated modeling approach. We used the SWAT-MODFLOW model, integrating the Soil and Water Assessment Tool (SWAT) and the Modular Finite-Difference Flow Model (MODFLOW), to analyze water balance segments and stream-aquifer interactions in the study region. Eflow for different management classes was determined using the flow duration curve (FDC) approach. The FDC method classifies Environmental Flow Management Classes (EMC) from “A” (natural or minor alteration) to “F” (critically modified). The relationship between the selected EMC and simulated streamflow, under the pressure of agricultural groundwater pumping, served as a constraint in evaluating exploitable groundwater alongside groundwater level fluctuations. As the traditional approach depends on average recharge for determining exploitable groundwater, this study also assessed the spatiotemporal distribution of groundwater recharge. Simulation periods were aligned with agricultural pumping schedules. Results indicated that groundwater pumping significantly impacts streamflow at the start of the irrigation period. Under moderately affected EMC and with an average groundwater level fluctuation of one meter, the exploitable groundwater during the irrigation period can reach up to 2.96 Mm3/day. With this amount of pumping, the average groundwater discharge to streams declined by around 13 %. While groundwater level fluctuations near the watershed outlet were minimal, in the upstream area, levels could decrease by as much as 2.5 m. The groundwater level fluctuation underscores the necessity of accounting for both spatial and temporal factors, particularly in highly affected regions.

Bio-physical pre-treatments in anaerobic digestion of organic fraction of municipal solid waste to optimize biogas production and digestate quality for agricultural use

This study optimized the anaerobic digestion (AD) of separated collected organic fractions of municipal solid waste (OFMSW) to produce energy and digestate as biofertilizer. Due to OFMSW’s partial recalcitrance to degradation, enzymatic (UPP2, MCPS, USC4, USE2, A. niger) and physical (mechanical blending, heating, hydrodynamic cavitation) pre-treatments were tested. Experimental and modeling approaches were used to compare AD performance regarding energy sustainability and digestate quality. Digestate was separated into solid and liquid fractions, and then chemically and physically characterized by investigating the nutrient release mechanisms. Principal Component Analysis was applied, equally weighing energy and digestate productions. Unlike previous studies focusing only on biogas, this study evaluated the effects of pre-treatments on both biogas and digestate production, viewing AD as a biorefinery process for urban waste valorization. Results showed that all pre-treatments were energetically sustainable, but enzymatic pre-treatments yielded digestates richer in nutrients (increase of 80% N, 200% P and 150% K as compared to OFMSW) and with greater organic matter degradation compared to physical pre-treatments. The liquid fraction of digestate from enzymatic pre-treatments had higher nutrient concentrations, while those from physical pre-treatments had more balanced nutrient content, making them more suitable for fertigation.

Remote sensing monitoring of irrigated area in the non-growth season and of water consumption analysis in a large-scale irrigation district

Globally, water scarcity threatens food security, especially in arid and semi-arid food-producing regions, such as the Hetao Irrigation District (HID), where the water consumption during the non-growth season (spring irrigation, autumn irrigation) accounts for more than 30 % of the total irrigation volume. Meanwhile, mapping the characteristics of spatial and temporal evolution of the area of cropland irrigated in the spring and autumn and the pattern of water consumption is crucial for strengthening the management of agricultural water use. Evaporation and infiltration of irrigation water are difficult to capture in time due to insufficient timeliness or accuracy of single remote sensing data. This study integrates seven remote sensing datasets (Landsat5, Landsat7, Landsat8, HJ-1A/B, GF-1, Sentinel-2 and MODIS) for the first time to build a high spatial-temporal resolution dataset, and combines the water index NDWI and MNDWI to extract the maximum water range formed after irrigation by manually adjusting the threshold method. In addition to the global land use/cover dataset (GLC FCS30–1985_2020), the cropland layer was superimposed to accurately identify the cropland spring irrigation and autumn irrigation range from 2000 to 2021 in the HID. In the past 20 years, spring-irrigated (SI) areas increased by 1012.60 km2 (+49.96 %), and the autumn-irrigated (AI) areas decreased by 512.63 km2 (-11.02 %). Combined with the quantity of water diversion and displacement, the characteristics of irrigation water consumption in the non-growth season were further analysed. The results showed that the water consumption of spring irrigation increased by 0.67×108 m3 (+22.26 %), and that of autumn irrigation increased by 4.34×108 m3 (+38.82 %). The decrease of autumn- irrigated area and the increase of water consumption were mainly related to the stability of autumn irrigation water, imperfect irrigation and drainage conditions and insufficient field water management. In 2020­2021, the area of non-growth “autumn irrigation - spring irrigation” repeated irrigation is about 1271.52 km2, which can be used as a key control area. This study provides a theoretical basis and direction for rational water use in non-growth seasons of irrigation districts.

How does pesticide reduction affect labour time and profitability? A crop production case study

CONTEXTNational and international agendas are focusing on reducing pesticides due to their detrimental effects on flora, fauna, and human health, which has led to the introduction of agri-environmental programmes aimed at reducing the risk of pesticides. Pesticide reduction in agriculture can have an impact on labour time requirements and profitability. OBJECTIVEWe used winter wheat, sugar beet, and potatoes as examples to analyse the changes in profitability and working time requirements, including management tasks. METHODSFor the calculations, we used five different production schemes for each crop: reference; (A) reduction of herbicides; (B) reduction of growth regulators, fungicides, and insecticides; combination of schemes (A) and (B); and organic production. The working time requirements for fieldwork and farm management work were modelled for each scheme and crop. The respective partial costs and benefits of the schemes were calculated for each crop. RESULTS AND CONCLUSIONSBased on the model assumptions, scheme (B) appears favourable in terms of working time requirements, and profitability of winter wheat and sugar beet. Scheme (A) offers synergies between the same parameters for potato production. Economic analysis shows that crop production with reduced pesticide use may even experience an increase in financial viability if the yield is not severely jeopardised, and farmers can be compensated through premiums and direct payments. SIGNIFICANCEOur results can support policy-making, since the labour time requirement and profitability of pesticide-reduced crop production can affect the success of voluntary agri-environmental programmes for the reduction of the risks from pesticide use in agriculture.

The integration of omics and cultivation-dependent methods could effectively determine the biological risks associated with the utilization of soil conditioners in agriculture

In the circular economy, reusing agricultural residues, treated biowaste, and sewage sludges—commonly referred to as soil conditioners—in agriculture is essential for converting waste into valuable resources. However, these materials can also contribute to the spread of antimicrobial-resistant pathogens in treated soils. In this study, we analyzed different soil conditioners categorized into five groups: compost from source-separated biowaste and green waste, agro-industrial digestate, digestate from anaerobic digestion of source-separated biowaste, compost from biowaste digestate, and sludges from wastewater treatment plants. Under Italian law, only the first two categories are approved for agricultural use, despite Regulation 1009/2019/EU allowing the use of digestate from anaerobic digestion of source-separated biowaste in CE-marked fertilizers. We examined the bacterial community and associated resistome of each sample using metagenomic approaches. Additionally, we detected and isolated various pathogens to provide a comprehensive understanding of the potential risks associated with sludge application in agriculture. The compost samples exhibited higher bacterial diversity and a greater abundance of potentially pathogenic bacteria compared to other samples, except for wastewater treatment plant sludges, which had the highest frequency of Salmonella isolation and resistome diversity. Our findings suggest integrating omics and cultivation-dependent methods to accurately assess the biological risks of using sludge in agriculture.

Crops biological protection: Phytopathogens growth inhibition by the entomopathogens

Background: The safety of agrarian preparations used for crop protection is a critical issue. In these regards, the minimization of usage of chemical pesticides containing artificial harmful substances is very important. Thus, the elaboration of innovative harmless biopesticides, based on biological enemies of pests, is very desirable. Microbe-based biopesticides can significantly increase the quality of agricultural production. Objectives: This research aims to develop ecologically safe, entomopathogenic microbe based biopesticides for use in green agriculture to improve agricultural production qualityIt includes the quality of vegetables, cereals, and fruits, as well as meat, milk, and eggs from animals that consume plant-based feed cultivated using recommended methodologies. Context and purpose of this study: This article was devoted to the consideration of bactericide effect of non-cellular extracts of entomopathogens against the various phytopathogens, as the potential prospective innovation for elaboration of plant protection safe biopesticides. Results: The majority of the studied entomopathogens can synthesize the compounds which inhibit the growth of phytopathogens. Entomopathogenic strains BT 2675, BL 200-4, and LS 2728 were found to significantly inhibit the growth of phytopathogens such as Pectobacterium, Xanthomonas, Rhodococcus, Curtobacterium, and Pseudomonas genera. According to spectroscopy the antiphytopathogenic effect is caused by an active component which is probably lipoprotein complex. Further detailed research on this is planned. Conclusions: Non-cellular extracts of entomopathogenic Bacillus are effective against the various plant pathogens. The identified antimicrobial properties of non-cellular extracts of entomopathogenic can be potentially used for the elaboration of plant protection safe biopesticides. Keywords: Bacillus thuringiensis (BT), Brevibacillus laterosporus (BL), Lysinibacillus sphaericus (LS), non-cellular extract, phytopathogen, entomopathogen, safe biopesticide

Phytochemical Study of Ethanol Extract of Gnaphalium uliginosum L. and Evaluation of Its Antimicrobial Activity.

This study evaluates the antibacterial and antifungal effects of ethanol extracts from Gnaphalium uliginosum L. derived from freshly harvested plant biomass, including stems, leaves, flowers, and roots. The extract was analyzed using gas chromatography-mass spectrometry (GC-MS) to determine its antimicrobial activity against phytopathogenic bacteria and fungi. Two methods were used in the experiments: agar well diffusion and double serial dilution. Extraction was carried out using the maceration method with different temperature regimes (25 °C, 45 °C, and 75 °C) and the ultrasonic method at various powers (63-352 W) for different durations (5 and 10 min). It was found that the 70% ethanol extract obtained through the ultrasonic experiment at 189 W power for 10 min and at 252 W power for 5 min had the highest antimicrobial activity compared to the maceration method. The most sensitive components of the extracts were the Gram-positive phytopathogenic bacteria Clavibacter michiganensis and the Gram-negative phytopathogenic bacteria Erwinia carotovora spp., with MIC values of 156 μg/mL. Among the fungi, the most sensitive were Rhizoctonia solani and Alternaria solani (MIC values in the range of 78-156 µg/mL). The evaluation of the antimicrobial activity of extracts using the diffusion method established the presence of a growth suppression zone in the case of C. michiganensis (15-17 mm for flowers, leaves, and total biomass), which corresponds to the average level of antimicrobial activity. These findings suggest that G. uliginosum has potential as a source of biologically active compounds for agricultural use, particularly for developing novel biopesticides.

Producción de beauveria bassiana para la formulación de bioplaguicidas

The harmful effects of chemicals in conventional agriculture and the growing demand for food free of toxic residues has developed environmentally sustainable strategies. An effective alternative for integrated pest management in agricultural crops are biopesticides formulated with microorganic structures or from the production of active compounds. This paper describes the production processes of Beauveria bassiana for formulating biopesticides for agricultural use. The information was collected through a systematic search in Research Gate, Google Scholar, Science Direct and PubMed, using keywords such as production, Beauveria bassiana, solid fermentation, liquid fermentation and metabolites. The results affirm that B. bassiana is one of the microorganisms with great potential to produce biopesticides, due to the entomopathogenic mechanism of action and secondary metabolites, which can be used for the biological control of phytophagous insects. Likewise, for the formulation of B. bassiana it should be considered a profitable culture medium for large-scale production, also the control of environmental variables such as temperature at 25 oC, relative humidity 65-70 %, pH of 5.4, propagation time between 4 to 8 days, and for the liquid fermentation process, a constant agitation between 200 to 400 rpm must be maintained. Biological products represent an alternative to minimize the use of synthetic pesticides, reduce environmental pollution and ensure food safety and security.

Combination of recycled cellulose with nano-thick flower layered double hydroxides: Biomass water retention slow-release fertilizer for sustainable agriculture

The development of crop nutrient, water utilization and increasing the renewability of waste resources sustainable agriculture is essential for improving sustainable agriculture. In this study, a type of nanothick floral layered double hydroxides (nLDHs) for fast and effective pesticide adsorption was created using cyclodextrin (CD) induction. After that, it was composited with recycled cellulose (PCe) derived from waste biomass (pomelo peel). A novel slow-release hydrogel fertilizer (N@nLDHs/PCe-PAA) was synthesized through the graft copolymerization of acrylic acid (AA), which was then employed as a nutrient (urea) carrier in the nLDHs/PCe composite. The swelling, water retention and slow-release capabilities of slow-release fertilizer was evaluated. Additionally, crop cultivation tests were conducted on the material to ascertain its potential use in sustainable agriculture. The results shown that N@nLDHs/PCe-PAA had a swelling rate of 197.02 g/g at 600 min, the water retention rate reached 21.02 % in soil at 60 d, and a nutrient release of 68.78 % in soil at 60 d, which were in accordance with European Committee for Standardization (CEN) standards. Besides, the experiment of crop cultivation showed that N@nLDHs/ CPE-PAA had obvious promotion effect on plant growth, which could improve the root system, rhizomes, chlorophyll content, and relative water content in the leaves of the plants. Therefore, this novel slow-release hydrogel fertilizer (N@nLDHs/PCe-PAA) not only promotes resource reproducibility, but also has excellent soil water retention, slow-release nutrient properties and a function of promoting plant growth. It has great value in promoting the sustainable development of agriculture.

Dietary Exposure to Pesticide and Veterinary Drug Residues and Their Effects on Human Fertility and Embryo Development: A Global Overview.

Drug residues that contaminate food and water represent a serious concern for human health. The major concerns regard the possible irrational use of these contaminants, since this might increase the amplitude of exposure. Multiple sources contribute to the overall exposure to contaminants, including agriculture, domestic use, personal, public and veterinary healthcare, increasing the possible origin of contamination. In this review, we focus on crop pesticides and veterinary drug residues because of their extensive use in modern agriculture and farming, which ensures food production and security for the ever-growing population around the world. We discuss crop pesticides and veterinary drug residues with respect to their worldwide distribution and impacts, with special attention on their harmful effects on human reproduction and embryo development, as well as their link to epigenetic alterations, leading to intergenerational and transgenerational diseases. Among the contaminants, the most commonly implicated in causing such disorders are organophosphates, glyphosate and antibiotics, with tetracyclines being the most frequently reported. This review highlights the importance of finding new management strategies for pesticides and veterinary drugs. Moreover, due to the still limited knowledge on inter- and transgenerational effects of these contaminants, we underlie the need to strengthen research in this field, so as to better clarify the specific effects of each contaminant and their long-term impact.

Research on the relative threshold of sustainable development of the complex system in the Yellow River Basin

As a complex system, the sustainability of basins is crucial for the development and stability of human society. This study creatively combined Otsu algorithm with analytic hierarchy process to determine the relative threshold of sustainable development of the Yellow River basin system, aiming to provide a new perspective for the application of threshold theory to the study of sustainable development. The results showed that among the 24 sustainable development evaluation indicators, the Per Capita Cultivated Area (F24) had the greatest impact, while the Ecological Water use (F2) and Agricultural Water use (F19) indicators had the greatest impact range. For different subsystems, the sustainable development indices of the eco-environment subsystem in the upstream of the Yellow River exhibited more significant changes, while that of the socio-economic subsystem exhibited more prominent changes in the midstream. However, the sustainable development indices of the water-sand subsystems in the upstream, midstream, and downstream fluctuated greatly, with a maximum value occurring downstream. The sustainable development threshold was further determined to be 0.408 for the complex system in the Yellow River Basin. The sustainable development thresholds differed in upstream, midstream, and downstream, which ranged from 0.4201 to 0.4524. Based on the sustainable development threshold, the sustainable development status of the Yellow River Basin had continued to improve since 2017, and a high level of sustainability had been maintained. However, the sustainable status is a dynamic process of change, and changes in natural conditions or policies may affect the state of sustainable development.

Zero-Emissions, Off-grid, Autonomous Houseboat – a Case Study of Selected Locations in Europe

Abstract The aim of this study was to assess the feasibility of creating a prototype of a self-sufficient houseboat that is capable of prolonged independence from power grids and freshwater sources. In this design, electricity demand is met by a photovoltaic installation, and the energy is stored in batteries. Fresh water for living needs may be obtained from many sources, depending on the environmental conditions, such as through purifying outboard water, desalinating seawater, and collecting and storing rainwater. No waste production of the vessel can be achieved in two ways: waste can be treated and discharged into a body of water, or processed into fertiliser for later use in agriculture. Four possible locations were analysed: Rome, Lisbon, Gdańsk and Stockholm. The findings reveal that the length of time for which the unit is autonomous and emission-free depends on the geographical location of the facility. In periods when there is overproduction of energy, the system can produce hydrogen, donate energy to the grid, use it for the needs of its own movement, or perform other useful work, e.g. cleaning or aerating the water body on which it is floating.

Identification of key anthropogenic and land use factors and ecological risk assessment of dissolved polycyclic aromatic hydrocarbons (PAHs) and organochlorine pesticides (OCPs) in an urbanized estuary in China

This study investigated dissolved PAHs and OCPs in Quanzhou Bay estuaries, assessed their ecological risk, and examined anthropogenic impacts on contaminant distribution. Results showed that dissolved ∑24PAH concentrations ranged from 117 to 709 ng/L (mean: 358 ng/L), with dominance of 2-ring PAHs (Naphthalene, 1-Methylnaphthalene, and 2-Methylnaphthalene). Dissolved DDT levels ranged from 0.06 to 0.49 ng/L (mean: 0.28 ng/L), while HCBz concentrations varied from 0.02 to 0.44 ng/L (mean: 0.20 ng/L). PAHs were higher in the north due to urbanization and transport, while OCPs showed higher levels in the south due to historical agricultural use. Rural areas, water bodies, and wetlands significantly influenced the behavior of PAHs according to Spearman correlation and lasso regression analyses. Quanzhou Bay was categorized as a low to medium risk area based on dispersion simulation and ecological risk assessment, highlighting implications for future sustainable development and policy planning. CapsuleThe coupled relationship between human activities and the distribution of dissolved PAHs and OCPs in urbanized estuaries was explored using statistical methods and GIS technology, providing valuable insights into environmental processes and pollutant control policies.

Classification of agricultural priority and reserved areas in Brandenburg under consideration of bio-economic climate simulations

Ensuring a crisis-proof food supply has become a key political issue. In Germany, official spatial planning allows the use of priority and reserved areas to secure land for agricultural use and regional food supply. The focus should be particularly on climate-resilient areas that also have a stable yield potential in the future. This paper supplements widely used, static approaches for determining priority and reserved areas with a dynamic bio-economic analysis that takes future climate scenarios into account. The results for the German federal state of Brandenburg show a high area equivalence between the static and dynamic approaches. In the case of data gaps, for example, static approaches such as soil quality indices can serve as an adequate proxy for future yield potentials. However, not all climate-robust areas can be classified as potential reserved or priority areas. Furthermore, areas that show low yield potential under future conditions are not released for other land uses. Feedback from stakeholders involved in the study showed that the use of the dynamic approach and a target value using the results of a foodshed model lead to broad acceptance. The method developed here can make a valuable contribution to climate change adaptation in spatial planning instruments.