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Naturally-occurring highly-complexed and polymerised organics such as humic acids (HA), due to their large negative charge, play a crucial role in biogeochemistry of trace metals (TM). Toxic (Cd) as well as essential (Zn, Cu, Mn) TM bind strongly to HA, but how these organo-metalic forms influence metal uptake by plants is poorly understood. A solution culture study was conducted to characterize the effects of different concentrations of HA (0–225 mg/L) on the growth and element uptake/distribution in roots, shoots and hypocotyls of radish ( Raphanus sativus L.) exposed to Cd (0.5 mg/L) contamination. After 10-d-exposure to applied treatments, Cd induced phytotoxicity; in contrast, different concentrations of HA had no influence on biomass, but decreased concentration of most TM in examined tissues (Cu by 4.2-fold, Zn by 2.2-fold, Cd by 1.6-fold and Mn by 34%) and their total plant accumulation (Cu by 73%, Cd by 39%, Zn by 29% and Mn by 22%). HA influenced the transport/distribution of TM, decreasing accumulation in roots and increasing their translocation/deposition in shoots, with no effect on TM content in edible hypocotyls. Chemical speciation modelling of the rooting medium confirmed predominance of free metallic forms in the control (no HA) and the pronounced organo-metal complexation in the HA treatments. The results provide evidence of strong capacity of HA to decrease phytoavailability and uptake of Cd, Zn, Cu and Mn while being non-toxic even at relatively high concentration (225 mg/L). Thus, HA, as naturally present soil components, control mobility and phyto-extraction of most TM as well as their phyto-accumulation. [ABSTRACT FROM AUTHOR]

BACKGROUND: In agricultural systems, heavy metals pose severe risks to the health of soil-plant-animal-human continuum. Drainage channels, as integral components of agricultural landscapes, contain sediment material that can be both a source and a sink of metals and other toxic/persistent elements due to its highly reactive interfaces and strong binding affinity. The drainage channel network in a case study area of Vojvodina (Serbia) is not appropriately protected from contamination, nor is it maintained regularly (e.g. by desilting), thus endangering and potentially decreasing the ecological value of surrounding water and agricultural land resources, i.e. exposing food production to potential contaminants. In this study (2004-2012), Cd and Zn concentrations were analysed in 100 samples from 46 drainage channels sediments spread along the areas of themost intensive agricultural land use in Vojvodina. RESULTS: Among the samples measured, 5% had Cd and 14% had Zn concentrations above the maximally permitted levels, indicating that some drainage channel sections have been exposed to different point and non-point source pollutants. The maximum detected concentrations of the analysed elements were >50% (Zn) and were as much as 11-fold (Cd) higher than their remediation values. CONCLUSION: There is a strong need for the establishment of qualitative monitoring of channel sediment media in agroecosystems closely linked with complex pollution sources (intensive agriculture, industry, urban zones). [ABSTRACT FROM AUTHOR]

The Asian rice gall midge (Orseolia oryzae (Wood-Mason)) is a major insect pest in rice cultivation. Therefore, development of a reliable system for the timely prediction of this insect would be a valuable tool in pest management. In this study, occurring between the period from 2013–2018: (i) gall midge populations were recorded using a light trap with an incandescent bulb, and (ii) climatological parameters (air temperature, air relative humidity, rainfall and insulations) were measured at four intensive rice cropping agroecosystems that are endemic for gall midge incidence in India. In addition, weekly cumulative trapped gall midge populations and weekly averages of climatological data were subjected to count time series (Integer-valued Generalized Autoregressive Conditional Heteroscedastic—INGARCH) and machine learning (Artificial Neural Network—ANN, and Support Vector Regression—SVR) models. The empirical results revealed that the ANN with exogenous variable (ANNX) model outperformed INGRACH with exogenous variable (INGRCHX) and SVR with exogenous variable (SVRX) models in the prediction of gall midge populations in both training and testing data sets. Moreover, the Diebold–Mariano (DM) test confirmed the significant superiority of the ANNX model over INGARCHX and SVRX models in modeling and predicting rice gall midge populations. Utilizing the presented efficient early warning system based on a robust statistical model to predict the build-up of gall midge population could greatly contribute to the design and implementation of both proactive and more sustainable site-specific pest management strategies to avoid significant rice yield losses. [ABSTRACT FROM AUTHOR]

Biochar is a carbon-rich material prepared from the pyrolysis of biomass under various conditions. Recently, biochar drew great attention due to its promising potential in climate change mitigation, soil amendment, and environmental control. Obviously, biochar can be a beneficial soil amendment in several ways including preventing nutrients loss due to leaching, increasing N and P mineralization, and enabling the microbial mediation of N2O and CO2 emissions. However, there are also conflicting reports on biochar effects, such as water logging and weathering induced change of surface properties that ultimately affects microbial growth and soil fertility. Despite the voluminous reports on soil and biochar properties, few studies have systematically addressed the effects of biochar on the sequestration of carbon, nitrogen, and phosphorus in soils. Information on microbially-mediated transformation of carbon (C), nitrogen (N), and phosphorus (P) species in the soil environment remains relatively uncertain. A systematic documentation of how biochar influences the fate and transport of carbon, phosphorus, and nitrogen in soil is crucial to promoting biochar applications toward environmental sustainability. This report first provides an overview on the adsorption of carbon, phosphorus, and nitrogen species on biochar, particularly in soil systems. Then, the biochar-mediated transformation of organic species, and the transport of carbon, nitrogen, and phosphorus in soil systems are discussed. This review also reports on the weathering process of biochar and implications in the soil environment. Lastly, the current knowledge gaps and priority research directions for the biochar-amended systems in the future are assessed. This review focuses on literatures published in the past decade (2009–2021) on the adsorption, degradation, transport, weathering, and transformation of C, N, and P species in soil systems with respect to biochar applications. [ABSTRACT FROM AUTHOR]

The coronavirus pandemic is having an economic impact, previously non-existent, on the world economy. The objective of this study is to analyze the impact of COVID-19 on agri-food companies in the region of Extremadura (Spain). A multiple-case study based on in-depth interviews was carried out in the period February 2020–January 2021. The results reveal the existence of negative and positive impacts, both financial (decrease in turnover; decrease/displacement in the demand for products; budget reduction in R&D projects; increase in certain product sales) and operational (difficulty in marketing activities, lack of staff, stoppage in company activity, and supply problems), depending, principally, on the nature of the products, the changes generated in consumer behavior, and mobility problems. Likewise, changes were observed in processes (search of clients in other markets, increased use of technology in communication and marketing activities, and development of new products) and procedures (reorganization of personnel activities, implementation of new health protocols) in companies to overcome the obstacles imposed by the new situation. In conclusion, the change in surrounding conditions, and the characteristics of the spread of the pandemic, have impacted on the strategies, behavior, processes, dynamics and results of organizations regardless of their size and the nature of their work product or service. [ABSTRACT FROM AUTHOR]

Extensive geographic areas of the world show a long-term atmospheric moisture deficit. Desertification of Rajasthan is concurrent with the strengthened weather extremality and mean annual air temperature (MAAT) rise over the western part of the Indian subcontinent. The present landscape aridification due to the precipitation decrease and reinforced windiness generates surface-cover dryness, aeolian erosion with a mass sediment transfer, salinity of excessively irrigated lands and groundwater depletion; altogether these pose major geo-environmental threats and settlement risks of the expanding Thar Desert. Livestock-overgrazing of sparse-vegetation contributes to ecological pressure to the fragile wasteland ecosystems with approximately three-quarters of the countryside affected to a certain extent by degradation and >50% exposed to wind erosion. Sand dune stabilisation by the drought-adapted tree plantation, the regional hydrology network regulation and the arid-land farming based on new xerophytic cultigens are the key land-use and mitigation strategies. Specific geomorphic palaeosettings predetermined patterned adaptive forms of the ancient desert inhabitation. Geo- and eco-tourism contributes to the arid-zone socioeconomic sustainability with regard to the rich natural and cultural heritage of the area. This study outlines the main effects of the current climate variations on the pristine and occupied lands of western Rajasthan, and the past and present relief transformations, and reviews the modern anthropogenic responses to desertification. [ABSTRACT FROM AUTHOR]

The COVID-19 pandemic has impacted worldwide food security including in Thailand. This review aims to understand people's behaviors with regard to promoting food security during the COVID-19 pandemic by covering three main cases at a community level: the food bank, the food exchange, and the food pantry. A systematic review of news content analysis and in-depth interviews were employed for data collection. Based on integrated behavioral models of motivation–opportunity–ability (MOA), the theory of planned behavior (TPB), and value–belief–norm (VBN), key results indicated that altruistic values including beliefs in opinion leaders and the benefits from food security behaviors were influences on people's practices. The attitude toward food as a crucial factor for living, the influence of family members and neighborhoods, and the perception of what constituted enough food led people's behavioral intentions with regard to food security. The intrapersonal communication of opinion leaders was an important initial step linking to people's understanding of others. The most frequent qualities of opinion leaders were: having a determination to help, thinking of the benefits of local people, and believing in community capacity. Self-reliance and procedural knowledge of how to behave were key messages, while personal media, local broadcasting towers, and social media were mainly employed to distribute these messages. Two-way and networking communication should be strengthened to promote sustainable food security during the crisis. [ABSTRACT FROM AUTHOR]

Waters are among to the most vulnerable environmental resources exposed to the impact of various point and non-point pollutants from rural/urban activities. Systematic and long-term monitoring of hydro-resources is therefore of crucial importance for sustainable water management, although such practice is lacking across many (agro-)hydro-ecosystems. In the presented study, for the first time, the spatial distribution (covering almost 9000 ha) and temporal variation (2006–2013) in certain quality parameters was characterized in drainage watercourses Tatarnica and Subic, whose catchment is rural and suburban areas close to the city of Novi Sad, Republic of Serbia. Based on majority of observed parameters, both watercourses belonged to I and II water quality classes, with occasional presence of certain parameters (e.g., suspended solids, total phosphorus; ammonium) at extreme values exacerbating both watercourses to classes IV and V. The value of the synthetic pollution index (i.e., a combined effect of all considered parameters) showed a higher degree of water pollution in watercourse Subic (on average 2.00) than Tatarnica (on average 0.72). Also, cluster analysis for watercourse Tatarnica detected two groups of parameters (mostly related to nutrients and organic matter), indicating more complex impacts on water quality during the observed period, in which elucidation thus established water quality monitoring program would be of great importance. [ABSTRACT FROM AUTHOR]