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Grey mould disease caused by the fungus Botrytis cinerea Pers is widely distributed on strawberries as the dominant postharvest disease. Therefore, fruits have been treated using a pin-to-plate corona electrical field at a high voltage electric field (HVEF) intensity of 3.61, 4.56, and 5.13 kV.cm^-1 for 60 minutes. The result revealed that the corona discharge demolished the B. cinerea growth using 20 kV.cm^-1 for 10 min in the Petri dishes. In addition, the treated strawberries at 4.56 kV.cm^-1 had an average infection rate of 23.33% compared with non-treated samples rate of 45.33%. The HVEF-treated samples showed significantly lower mass losses. The analysis of variance showed that the HVEF did not significantly affect the total soluble solids content, pH, titratable acidity, and softness; however, the lower acidity affected the Botrytis cinerea growth. No significant differences were observed among the mean values in the colour change parameters and colour difference for 4.56 kV.cm^-1 compared with the control, while the lightness was significantly higher. The result show that the corona electrical field was able to demolish the B. cinerea growth, and an electric field intensity at 4.56 kV.cm^-1 was found to extend the strawberries' cold storage and to lead to a lower mass loss.

This contribution presents a calculation method of indicators in agricultural transport. The tractor Zetor Forterra 8641 with a silage trailer was used. Calculations were performed with various weights of transported material: 2.5, 3.6, 5.8, 7.4 and 9.0 tons. The model was created concerning significant parameters of the transport set, engine characteristics and route. It considered splitting of the route into elementary sections, in which important route parameters were regarded as constant. Indicators were defined in every section (fuel consumption, emissions, etc.) and overall values were calculated as a sum. The set with 7.4 t of load reached the lowest unit costs 20.62 CZK.tkm^-1, transport output 79.51 tkm.h^-1 and unit consumption 0.14 L.tkm^-1. The set with the maximum load 9.0 t reached output 86.05 tkm.h^-1 but unit costs were 20.68 CZK.tkm^-1. Using the maximum capacity was not the most effective option. When the weight of a load increased (from 2.5 to 9.0 t), driving time extended from 0.28 to 0.46 h and hourly transportation output increased from 38.60 to 86.05 tkm.h^-1, unit consumption decreased from 0.24 to 0.13 L.tkm^-1. Total emissions significantly increased, but unit emissions decreased in average two times for each pollutant.

Performance of a tractor mounted solar-biomass hybrid dryer which utilise combined energy of solar and biomass was investigated. Drying behaviour of maize grains in the dryer was also investigated using 10 thin-layer mathematical models. The models were compared based on coefficient of determination (R²) and root mean square error (RMSE) values between experimental and predicted moisture ratios. Moisture content (MC) of grains in the dryer reduced from 19 ± 0.86% to 13 ± 0.4% (w.b.) in 5 h, compared to grains dried in open-sun which reached same MC in 15 hours. This resulted in average drying rate of 1.2 %.h^-1 compared to 0.4 %.h^-1 for grains dried in the open-sun leading to net savings in drying time of 67%. Overall mean temperature, 41.93 ± 2.7 °C in the dryer was 15.3 °C higher than the ambient temperature. Midilli Kucuk model was best to describe the thin-layer drying kinetics of maize in the dryer. It showed a good fit between the predicted and experimental data. The effective moisture diffusivity of grains dried in the dryer ranged between 1.45 × 10^-11 m².s^-1 - 3.10 × 10^-11 m².s^-1. An activation energy of 96.83 kJ.mol^-1 was determined based on the Arrhenius-type equation.

The objectives of this study were to establish the impact order of the oil-palm kernel processing variables, namely: kernel moisture content (KMC), kernel heating temperature (KHT), kernel heating duration (KHD), and kernel particle size (KPS) on the palm kernel oil (PKO) yield; to develop an empirical model for the PKO yield as influenced by the KMC, KHT and KHD; to investigate the effect of the KMC, KHT and KHD on the PKO quality; and to specify levels of the kernel variables for the maximum PKO yield with minimum variability. The study was undertaken using oil-palm kernels of unidentified variety from Nsukka, Nigeria. The statistical analysis of data was performed with Design-Expert 8P and Minitab 19 Software at P = 0.05. The impact order of the studied kernel variables on the PKO yield, using an expeller (MS-100), was found to be the KPS, KMC, KHD, and KHT. For the maximum PKO yield with minimum variability in the PKO yield, a KMC of 5% (wb), a KHT of 80 °C, a KHD of 10 min, and a KPS of 11 mm and above is recommended.

The maturation process is an important determining factor to initiate the fermentation process in olive fruit. Level of maturation classically determined by the color of the olive fruit. In this study, we aim to develop a measurable criterion based on physicochemical properties and surface roughness of two important olive varieties grown in Morocco. The hydrophobic/hydrophilic properties and the electron donor-acceptor character of the olives were calculated. The obtained results showed a very clear change in the electron donor character and the surface roughness of the two studied varieties. This change depended on the degree of maturity and the nature of the cultivar. The electron donor character decreased (two times) with an increasing degree of maturity for the Arbequina, contrary to the Picholine variety, which showed a significant increase (4 times). Surface roughness increased 10 times for the Arbequina and decreased 5 times for the Picholine as maturity progressed from the green to the black stage. These findings may be useful in the management/prediction of the process of table olive fermentation.

Based on the hypothesis that soil properties and productivity components should be affected by different tillage methods, field and laboratory experiments were conducted to study the effects of zero tillage (ZT), one pass of disc plough tillage (P), one pass of disc plough plus one pass of disc harrow tillage (PH) and one pass of disc plough plus two passes of disc harrow tillage (PHH) on the distribution of the bulk density, available water capacity, pH, organic matter, available phosphorus, iron oxide and aluminium oxide at different soil depths, and their effects on the soil productivity. The available water capacity, pH, organic matter and available phosphorus were found to increase with the degree of tillage, while the bulk density, iron oxide and aluminium oxide were found to decrease with the degree of tillage. The results show that the soil productivity index was significantly (P ≤ 0.05) affected by the tillage methods and found to increase with the degree of tillage.

This study investigated the influence of the moisture content and speed on the cutting force and energy of tannia cormels using the response surface methodology (RSM). The moisture content and cutting speed were varied over five levels each [95.79, 113.68, 136.68, 168.42, 242.11% moisture content (dry basis) and 10, 15, 20, 25, 30 mm×min^-1, respectively]. The highest and lowest cutting forces were 114.09 and 63.99 N at the corresponding moisture contents of 168.42 and 113.68% and at cutting speeds of 10 and 20 mm×min^-1, respectively. The highest and lowest cutting energies of 0.92 and 0.49 J were both obtained at a 136.68% moisture content, at the 10 and 20 mm×min^-1 cutting speeds, respectively. The regression models for predicting the cutting force and energy as a function of the cutting speed and moisture content showed that there was no linear relationship between the investigated properties and the independent variables considered which could be attributed to the non-homogeneous nature of tannia cormels. The optimum cutting force and energy were 72.89 N and 0.60 J, respectively, at a 95.79% moisture content and a 22.33 mm×min^-1 speed with a desirability of 0.80. These findings could serve as a guide for the development of chipping and cutting machines for tannia cormels.

The objective of this research was to design, construct and evaluate a variable chipping clearance cassava chipper for processors which will produce uniform and varying cassava chip geometry for multipurpose usage. It consists of a drive shaft with varying chipping clearances (6, 18, and 28 mm) to produce varied chip geometry. The average throughput capacity of the chipper was found to be 475.5 kg.h^-1 at a speed range of 460-800 rpm with a chipping clearance of 6-28 mm. The average chipping efficiency ranges from a minimum-maximum of 76.6-99.4% for the selected operational speeds and chipping clearances. The chipping capacity and the output to input ratio is dependent on the operational speeds and chipping clearances of the machine.

The article focuses on the research of tyre rolling resistances in the soil test channel environment. The specific monitored tyre was a Mitas TS05 10.0/75-15.3 10PR diagonal tyre with an arrow tread. The measurement itself was divided into two stages. In the first stage, measurements of rolling resistance were performed on a solid concrete base of the laboratory in order to determine the internal component of rolling resistance of the tyre. In the second stage, rolling resistances were monitored on forest soil deposited in the main body of the soil channel. The mentioned measurements of rolling resistance can be considered key for further evaluation of traction and energy properties of tyres. Despite some complications which occurred during the measurement, the results obtained indicate the conclusions reached by other researchers in the field. The main conclusion of this research is to confirm the justification of using the correct or optimal level of inflation pressures of tyres of mobile energy means depending on the properties of the surfaces on which they move in order to reduce not only their energy intensity but also greater environmental acceptability.

To investigate the effects of organic matter activators combined with a pig slurry on a soil's physical properties, a field experiment was carried out in a monoculture of corn (2015-2017). Three pig slurry application variants complemented with the activators in question, i.e. with PRP SOL spread directly on the soil surface (SOL), with Z'fix added to the slurry during the pig housing (ZF) and with a combination of both PRP SOL and Z'fix (ZF_SOL), were compared with just the pig slurry (C) under an equal dose of nitrogen and a uniform growing technology. According to the results, a positive effect of the penetration resistance with the pig slurry and the activators of organic matter (Z'fix and PRP SOL) was not proven. The saturated hydraulic conductivity was demonstrably better achieved with the Z'fix activator, but PRP SOL activator also provided a certain improvement. The largest change in the unit draught was observed in the ZF_SOL application (20% increase). The results seem ambiguous; however, they give a good indication of the activators' effect in practice. Nevertheless, the findings would certainly benefit from further verification.

The aim of this study was to evaluate the response pattern of diazotrophic microbes, denitrifiers and nitrifiers to different types of land use management, such as soybean monoculture (M) during 5 and 24 years (M5 and M24) and soybean-maize rotation (R) during 4 and 15 years (R4 and R15) in two subsequent years at the time point of flowering. Soil samples from a site recently introduced into agriculture (RUA) and a pristine soil under native vegetation (NV) were used as controls. Abundances of different functional groups of microbes were assessed using the direct quantification of marker genes by quantitative real-time PCR using extracted DNA from rhizosphere samples. In addition, soil chemical and physical properties were analysed and correlated with the abundance data from the functional microbial groups under investigation. Overall, the results indicate that the abundance of nifH genes was higher under R treatments compared to M treatments. The abundance of ammonium monooxygenase genes amoA (AOA) was generally higher under rotation systems and decreased under M24. RUA evidenced a negative effect on the establishment and development of AOA communities. The influence of land use on nirS abundance was inconsistent. However, R treatments showed a high abundance of nirK genes compared to M treatments. In both growing seasons, the abundance of nosZ genes was higher under NV compared with the other treatments. Furthermore, M24 treatment was related to strongly changed chemical and physical soil properties compared with the other sites. As expected, soil samples from RUA showed the strong dynamics of measured parameters indicating the high sensitivity of soils under transition to environmental parameters. Our results also indicated that the long-term crop rotation modified the abundance of the investigated microbial groups compared to the monoculture and increased soil chemical and physical quality. Therefore, our results provide evidence for a stimulatory effect of the long-term crop rotation on the abundance of microbes involved in N transformation.

Experiments were used to determine the potassium release from the non-exchangeable K (Kne) forms that are involved in plant nutrition and which replenish the pool of available K. Long-term stationary field experiments with different fertilisation systems (organic: farmyard manure, sewage sludge, straw; mineral: NPK, N) were carried out to study the potassium balance and the K content changes in the topsoil (0-30 cm) and subsoil (30-60 cm). The trials were located at three sites with different soil-climatic conditions. The following crops were rotated within the trial: potatoes (maize) - winter wheat - spring barley. All three crops were grown each year over 21 years. Positive correlations between the contents of the available K in the topsoil and the potassium balance (K inputs - K outputs) were observed. There were no statistically significant differences among the treatments. Depending on the soil properties, the ratio of non-exchangeable K (Kne) was 12-37% of the values obtained via the aqua regia extraction. Depending on the site, the amount released from the Kne forms to the available K form was 46-69 kg K/ha/ year. The use of K from the farmyard manure varied from 7.4% up to 25%. Due to the low K content in the sewage sludge, the long-term fertilisation with sludge may only lead to the depletion of the available K in the soil, similar to the sole N mineral fertilisation.

The concentration of Cu, Fe, Pb, Zn and As in the surface water intended for human consumption and other uses in the Mantaro River basin were analysed using multivariate methods. The water samples were collected from seven water bodies in the Junín region in June 2019, in the low discharge period. In each body of water, a sector with six sampling sites was established. The Cu, Fe, Pb, Zn and As contents were determined by the flame atomic absorption spectrophotometry method. The correlation analysis revealed positive and significant correlations (P < 0.05) for the Zn/Pb, Pb/Fe and Zn/Fe pairs with a good association, higher than 0.80 and for the Pb/Cu, Fe/Cu, As/Pb and As/Zn pairs a weak degree of association (P < 0.05). The analysis of the main components showed three components with their own values > 1. The hierarchical grouping analysis classified the evaluated water bodies into three groups according to the concentration of the Cu, Fe, Pb, Zn and As. The high concentrations of heavy metals and arsenic recorded in the CIMIRM and MERIS irrigation channels reveal that the Mantaro River continues to be a sink for mine wastewater discharges and runoff from mining liabilities at the headwaters of the Mantaro basin. It is, therefore, necessary to implement urgent management policies to control and reduce the levels of contamination by potentially toxic metals and metalloids in the Mantaro River.

The aim of the study was to evaluate the effect of clay as an amendment to decrease the mobility and plant availability of potentially toxic elements (PTEs). Kaolinite and vermiculite were added at a 9% application rate to a contaminated garden soil from Kutná Hora. Half of the original soil was acidified by the addition of HNO₃, to observe the effect of the pH on the adsorption of the PTEs. The samples were analysed four times over an eight-week period to evaluate the effect of the clay additions on the As, Cd, Pb and Zn plant availability and different fractions of the BCR sequential extraction. The results indicate that the PTEs were mainly bound by ion/cation exchange on the edges of the clay minerals and onto the Fe/Mn oxides and organic fractions in the soils. The significance (P < 0.05) of the pH was observed for the plant availability of the PTE, especially on the As and Cd. A comparison of the vermiculite in the form of chunks and as powder displayed the most statistically significant results, where the vermiculite powder significantly decreased the plant availability of the As, Cd and Pb, while the opposite effect was observed for the Zn.

The available water capacity (AWC) is the most commonly used parameter for quantifying the amount of soil water that is readily available to plants. Specific AWC and soil organic carbon storage (SOCS) profiles are consequences of the soil development process. Understanding the distributions of AWC and SOCS in soil profiles is crucial for modelling the coupling between carbon and water cycle processes, and for predicting the consequences of global change. In this study, we determined the variations in the AWC and SOCS from the surface to a depth of 100 cm in soils developed from dark brown soil, skeletal dark brown soil, meadow dark brown soil, white starched dark brown soil, meadow soil, and boggy soil in the Changbai Mountains area of China. The AWC and SOCS profiles were calculated for each main soil group/subgroup using only the readily available variables for the soil texture and organic matter with the soil water characteristic equations. The results showed the following. (1) The AWC and SOCS decreased initially and then increased, before decreasing again in soils developed from dark brown soil to boggy soil, where the maximum SOCS occurred in the white starched dark brown soil, and the maximum AWC in the dark brown soil. (2) The SOCS was decreased by deforestation and concomitant soil erosion, but the negative impact of this decrease in the SOCS in the Changbai Mountains area was not caused completely by reductions in AWC. (3) In the soil development process from dark brown soil to boggy soil in response to deforestation, the AWC distribution differed in the profile and even among individual layers, whereas the SOCS was mainly present in the upper layer.

Changes in land use and land cover (LULC) are generally associated with environment pollution and the degradation of natural resources. Detecting LULC changes is essential to assess the impact on ecosystem services. The current research studies the impact of the LULC change on the soil loss and sediment export in a period of 43 years from 1972 to 2015. Landsat imageries were classified into five classes using a supervised classification method and the maximum likelihood Algorithm. Then, the sediment retention service for avoiding reservoir sedimentation was assessed using the InVEST SDR (integrated valuation of ecosystem services and trade-offs sediment delivery ratio) model. The results showed that the changes are very important in this study period (1972-2015). Forests were reduced by 18.72% and croplands were increased by approximately 54%. The InVEST SDR model simulation results reveal an increase in the sediment export and soil loss, respectively, from 1.68 to 5.57 t/ha/year and from 15.22 to 43.61 t/ha/year from the year 1972 to 2015. These results highlight the need for targeted policies on integrated land and water resource management. Then, it is important to improve the common understanding of land use and land cover dynamics to the different stakeholders. All these can help in projecting future changes in the LULC and to investigate more appropriate policy interventions for achieving better land and water management.

We quantified the soluble fractions of the soil organic carbon (SOC) concentrations and the total and water-soluble trace elements in soils contaminated by household waste and remediated via the addition of green manure over 13 years and identified the main factors controlling the vertical distribution and accumulation of the trace elements. Green manure favoured the active formation of soil organic matter. The SOC of the examined soils was characterised by the active stabilisation by mineral soil compounds, but by a low degree of humification. The soils showed increased concentrations of Cr and Ni ions. The SOC and different soil compounds enriched by Si, Ca, and Mn ions were the important determinant for the distribution of Sr, V and Cu ions, as well as for the distribution of Pb and Cr ions bound to the water-soluble components of the soils. The low degree of SOC humification may be one of the main reasons of the high concentrations of Cu and Pb ions in the composition of the water-soluble soil compounds. The nickel ions were mainly associated with compounds enriched by the Al and Fe ions. The extremely high percentage concentration of the Ni ions in the water-soluble components of the soils may be result of the absence of the Ni ions adsorption by humic substances.

Organic acids could improve the phosphorus (P) availability through enhancing the release of inorganic phosphorus (P_i) in the soil. However, the effects of organic acids on the P_i release are still poorly understood, especially from soils with different organic matter contents. Here, a biochemically produced humic acid and P fertiliser were added to the soil to modify the content of the soil organic matter (SOM) and soil P, respectively. And then the soil samples were incubated at 25 °C for 30 days. The release of P_i fractions (such as H₂O-P_i, NaHCO₃-P_i, NaOH-P_i, HCl-P_i, and Residual-P) from the soils with different organic matter contents in the presence of citric, oxalic, and malic acids was evaluated using a sequential chemical fractionation method. The results showed that the release of the NaHCO₃-P_i, NaOH-P_i, and HCl-P_i fractions also showed a decreasing trend with an increasing content of soil organic matter, and more NaOH-P_i than the other P_i fractions was generally released in the presence of organic acids. Considering the types of organic acids, oxalic acid and malic acid most effectively and least effectively released P_i, respectively. The path analysis indicated that the NaOH-P_i release had the highest direct and indirect effects on the total inorganic P (TP_i) release. NaOH-P_i was, therefore, the most effective source of P_i in the Mollisols.

A general adsorption model able to provide a good description of the multilayer adsorption of ions and molecular compounds under any circumstances is proposed in this paper. In order to reach this goal, a general form of isotherm was deduced based on the Gapon equation and classical isotherm forms. The adsorption of molecular compounds with diverse hydrophobicity and acid-base characteristics were investigated and validated with a new model for the adsorption of four pesticides on different soils. The adsorption capacity and adsorption energy estimated by the new model were found to be related to the organic matter content of the soil. Great differences were found in the isotherm parameters (A_i, K_i, and n_i) among both the soils and compounds investigated here.

The annual mean rainfall erosivity (R) indicates the potential soil loss caused by the precipitation and runoff and is used to predict the soil loss from agricultural hillslopes. R is calculated from rainfall stations with continuously recording rainfall databases. However, many short-term real-time rainfall databases that also relate to the rainfall intensity are not readily available around Taiwan, with the hourly rainfall data being predominantly available. The annual mean rainfall erosivity calculated by the 10-min rainfall data accumulation converted to the 30-min rainfall data (R_{10_30}) can be estimated using the annual mean rainfall erosivity calculated by the 10-min rainfall data accumulation convert to the hourly rainfall data (R_{10_60}) that are calculated from the kinetic energy calculated by the 10-min rainfall data accumulation converted to the hourly rainfall data (E_60j). The maximum 60-min rainfall intensity calculated by the 10-min rainfall data accumulation converted to the hourly rainfall data (I_60j) has been established in rainfall stations throughout southern Taiwan. The 10-min rainfall data set consists of 15 221 storm events from 2002 to 2017 monitored by 51 rainfall stations located in the tropical regions in Taiwan. According to the results of this study, the average conversion factors of the kinetic energy (1.04), rainfall erosivity (1.47), and annual mean rainfall erosivity (1.30) could be estimated based on the 10-min rainfall data.

Irrigation can be responsible for salt accumulation in the root zone of grapevines when late autumn and winter precipitation is not enough to leach salts from the soil upper horizons, turning the soil unsuitable for grape production. The aim of this work is to present a novel methodology to outline areas, within a drip-irrigated vineyard, with a low soil moisture content (SMC) during, and after, an 11-month agricultural drought. Soil moisture (SM) field measurements were performed in two plots at the vineyard, followed by a geostatistical method (indicator kriging) to estimate the SM class probabilities according to a threshold value, enlarging the training set for the classification algorithms. The logistic regression (LR) and Random Forest (RF) methods used the features of the Sentinel-1 and Sentinel-2 images and terrain parameters to classify the SMC probabilities at the vineyard. Both methods classified the highest SMC probabilities above 14% that is located close to the stream at the lower altitudes. The RF method performed very well in classifying the topsoil zones with a lower SMC during the autumn-winter period. This delineation allows the prevention of the occurrence of areas affected by salinisation, indicating which areas will need irrigation management strategies to control the salinity, especially under climate change, and the expected increase in droughts.

The aim of the article was to verify the curve number (CN) values given in the National Engineering Handbook (NEH) methodology, whether they really correspond to all wide-row crops. The tested crops were maize, hops and potatoes grown using conventional and soil conservation technologies. All these crops are classified as wide-row crops, but they are very different in terms of the cultivation process. The basis for the calculation of our CN values were field measurements carried out using a rainfall simulator within the time span from 2014 to 2020 on the soil corresponding to hydrological group B in two repetitions: naturally dry soil corresponding to an ARC II curve and saturated soil corresponding to an ARC III curve. The results show that our calculated CN values for the conventional cultivation of wide-row crops are, in principle, the same as the CN values given in the NEH methodology. On the contrary, a certain difference was recorded in the soil conservation technologies with plant residues on the surface, in the case of naturally dry soil. Lower CN values are clearly seen in the technologies of no-till maize, strip-till maize and hops with catch crops, which was confirmed by the statistical tests, probably due to the interception and surface roughness.

The Nilgiri Biosphere, being one of the critical catchments, a small agricultural watershed of Udhagamandalam has been analysed to show the need to improve the agriculture by reducing the soil erosion. For this study, the land use and land cover classification was undertaken using Landsat images to highlight the changes that have occurred between 1981 and 2019. The Revised Universal Soil Loss Equation (RUSLE) method and the Geographic Information System (GIS) was used in this study to determine the soil erosion vulnerability of Sillahalla watershed in the Nilgiri Hills in Tamilnadu. This study will help to promote the economic development of the watershed with proper agricultural planning and erosion management. This study focuses on the estimation of the average annual soil loss and to classify the spatial distribution of the soil loss as a map with the RUSLE method and GIS. To estimate the average annual soil loss of the study area, GIS layers of the RUSLE factors like rainfall erosivity (R), soil erodibility (K), slope length and steepness (LS), cover management (C) and conservation practice (P) were computed in a raster data format. The total soil loss and average annual soil loss of the study area for 1981-1990,1991-2000, 2001-2010, 2011-2019 were found to be 0.2, 0.254, 0.3, 0.35 million t/year and 31.33, 37.78, 46.7, 51.89 t/ha/year, respectively. The soil erosion rate is classified into different classes as per the FAO guidelines and this severity classification map was prepared to identify the vulnerable areas.

Straw return is considered an effective way to improve the soil organic carbon (SOC) content of farmland. Most studies have suggested that a straw application increases the SOC content; however, some suggest that a straw application reduces the SOC content when used in combination with mineral fertilisation. Therefore, a meta-analysis of the effect of a straw application on the SOC change is needed. This study comprises a meta-analysis of 115 observations from 65 research articles worldwide. Straw applications can significantly increase the proportion of the SOC in the soil. Straw applications caused a significant microbial biomass carbon (MBC) increase in tropical and warm climatic zones. The MBC increase was higher than the SOC increase. For agriculture, the most important soil functions are the maintenance of the crop productivity, the nutrient and water transformation, the biological flora and activity, and the maintenance of the microbial abundance and activity. These functions should be prioritised in order to maintain the SOC function and services. Straw applications should not be excessive, especially when combined with mineral fertilisation, in order to avoid the loss of carbon from the straw in the form of greenhouse gases. A large amount of unused fertiliser also leads to a series of environmental problems.

The Mun River in NE Thailand is one of the significant tributaries of the Lower Mekong River. Its poor river quality has been reported and agricultural activities were claimed to be major causes. This study aims to assess the best management measures appropriately responsive to the nutrient pollution in the Mun River Basin's agricultural ecosystems. The data used for the analysis were acquired from field measurements during the 2018 wet season via satellite retrieval and secondary data collection. Linkages between land-soil datasets and hydro-water quality datasets were assessed through a canonical correlation analysis. The results suggest possible conservation measures with crop yield improvement and fertiliser cost reduction in the western basin. For the southern basin, which exhibits high sediment loading, integrated conservation measures for soil loss reduction with in-stream flow deceleration should be chosen. In the eastern basin, woody buffer strips and check dams should be prioritised. Both nutrient and sediment pollution were experienced in the middle part of the Mun River Basin and applications of low-P manure with mineral NK are recommended. Nonetheless, other soil-water conservation measures can be optionally applied to enhance the effectiveness in the watershed management.

Thallium (Tl) is a toxic trace element with a highly negative effect on the environment. For phytoextraction purposes, it is important to know the limitations of plant growth. In this study, we conducted experiments with a model Tl-hyperaccumulating plant (Sinapis alba L., white mustard) to better understand the plant tolerance and/or associated detoxification mechanisms under extreme Tl doses (accumulative 0.7/1.4 mg Tl, in total). Both the hydroponic/semi-hydroponic (artificial soil) cultivation variants were studied in detail. The Tl bioaccumulation potential for the tested plant reached up to 1% of the total supplied Tl amount. Furthermore, it was revealed that the plants grown in the soil-like system did not tolerate Tl concentrations in nutrient solutions higher than ~1 mg/L, i.e., wilting symptoms were evident. Surprisingly, for the plants grown in hydroponic solutions, the tolerable Tl concentration was by contrast at least 2-times higher (≥ 2 mg Tl/L), presumably mimicking the K biochemistry. The obtained hydroponic/semi-hydroponic phytoextraction data can serve, in combination, as a model for plant-assisted remediation of soils or mining/processing wastes enriched in Tl, or possibly for environmental cycling of Tl in general.

The intensive urbanisation of terrestrial environments and industrial activity have an effect on the accumulation of risky metals in the soil and increase the toxicological risk to the terrestrial ecosystems and human health. Ninety-six topsoil samples from of St. Petersburg Russia as the source of the content of seven key risky metals (As, Cd, Pb, Zn, Ni, Cu, Hg) and polycyclic aromatic hydrocarbons (PAHs) have been investigated. To identify the spatial distribution of the risky metals and PAHs, GIS technologies have been used. Based on the data obtained, interactive maps of urban soil pollution were made. The spatial distribution of seven metals and their metalloids greatly varied from the local anthropic inputs. The results indicate that the highest concentrations of copper, mercury and lead were found in the urban environment. The most polluted areas were located in the city centre and the areas adjacent to industrial zones. The topsoil in this area represents an environmental pollution risk with regards to the elements Cu > Pb > As > Zn > Ni > Hg > Cd. The contents of the risk-type elements in the industrial area were higher than those in other land-use types in the north of city, indicating a considerable risk of metal migration and accumulation to the Neva River, the Gulf of Finland and the groundwater.

Zn is an essential micronutrient involved in a wide variety of physiological processes. Soils are tested for zinc in many countries with several extractants. Each country has its validated methods, best-suited for its soils. The current study was designed to compare different zinc content measuring methods with seventy-one samples from Hungary. The data were first compared for the whole dataset and then in certain categories such as CaCO₃-content, pH, texture and clay content. The zinc content was determined by the water extraction, KCl-EDTA (ethylenediaminetetraacetic acid), Mehlich 3, CoHex (cobalt hexamine trichloride), and XRF (X-ray fluorescence) methods. Based on the analyses of all the data, we can conclude that all the methods are different. However, further analyses during the comparison of the methods based on the influencing factors, such as the pH, lime content, texture class, and clay content proved that, in some of the cases, there are similarities among the methods and, this way, we can get more knowledge on the measurements and the results provided. Farmers can gain extra knowledge from the comparison of the influencing factors to know where intervention is needed to use extra Zn for the proper fertilisation of their plants.

Water scarcity is a major constraint facing vegetable production sustainability in open field farming of arid regions like the Kingdom of Saudi Arabia. This study was carried out in an open field of the Research and Training Station of King Faisal University in the eastern region of the Kingdom. The objective was to assess the influences of the polymer addition (PA), deficit irrigation regime (DIR), and their combination on the production and water use efficiency (WUE) of muskmelons. PA treatments of 0.0, 0.2 and 0.4% and the irrigation treatments of 100, 75 and 50% of reference evapotranspiration (ET_o), were imposed throughout the growth stages of muskmelons under surface drip irrigation (DI) and subsurface drip irrigation (SDI). The polymer addition of 0.4% enhanced the field water holding capacity of the medium sandy soil within the locality of the emitters by 43.6%. The soil water content of the surface layer within the vicinity of the polymer amended soil layer increased in a range of 72.4 to 99.4% to the combined influences of the 0.4% PA with the DI and SDI, but were marked more under the SDI. The combination of the 100% ET_o DIR with polymer additions significantly (P < 0.05) enhanced the muskmelon fruit yield (MFY) under the SDI compared to DI. The PA of 0.4% improved WUE and MFY by 67.7, 70.4% under the SDI, and 58.6, 24.2% under the DI, respectively. Without the polymer addition (0.0% PA), the MFY significantly (P < 0.05) decreased with the increase of the DIRs under both DI and SDI.

Forest soils respond dramatically to management changes compared to other soils influenced by different land-use forms. This work aimed to compare the soil conditions in four different zones in a temperate forest in a biosphere reserve in Mexico, using a minimum data set (MDS) based on volcanic soils properties to develop a soil quality index (SQI). For this purpose, two different MDSs were used, one obtained from an expert opinion and the other through a multivariate principal component analysis (PCA). The soil quality assessment was conducted in a biosphere reserve in Mexico, where volcanic soils predominate. Four different areas were studied. Overall, six different types of SQI were calculated for each area, for which linear and nonlinear functions were used and the additive and weighted method. The six SQI showed a significant difference between the four areas of study. The zone with the highest SQI values was the zone with a preserved pine forest, followed by the zone with a pine forest managed by the population, and the zones with a pine forest and grassland in recovery showed the lowest SQI. The linear score indices obtained by the PCA indicated the better ability to differentiate the calculated SQI values, which would provide information to contribute to the stakeholder management and decision making in the protection, conservation and management of the ecosystems present in the biosphere reserve.