A georeferenced baseline and GIS-based screening of natural radioactivity in coastal sediments and nearshore waters of Da Nang, Viet Nam.

Colonization of Salmonella Newport and Microbiome Analyses of Bulb Onions Grown in Artificially Contaminated Soil at Lab-Scale Under a Controlled Environment.

Fire-resistant woody species have encroached into grassland and rangeland ecosystems worldwide. Sapling and mature individuals of many of these species are fire resistant because they resprout following fire; however, seedlings may be vulnerable to fire. We quantified fire temperature and flame length of winter and summer prescribed fires in two grass fuel types (native mixed-grass or tallgrass) and their effects on honey mesquite ( Prosopis glandulosa ) seedling mortality in the Southern Great Plains (SGP), US. Mesquite seeds were planted in replicated plots in both grass fuel types in each of two consecutive years. Plots were burned in the winter when seedlings were 10 or 22 mo old, or in the summer when they were 17 mo old. Fire temperature was measured at 1-second intervals at −1 cm, 0 cm, 10 cm, 30 cm, and 1 m heights. Flame length and fire temperature duration in seconds >60°C (FTD60) at 0 cm (soil surface) were better predictors of seedling mortality than was peak fire temperature. Highest seedling mortality was achieved when FTD60 at 0 cm was >2 minutes. We suggest these results modify the “60°C for 1 minute” hypothesis when applied to a population of seedlings exposed to rapidly moving prescribed headfires. Averaged over both cohorts, seedling mortality was greatest in tallgrass/summer fires (84.0%), intermediate in tallgrass/winter (69.2%) and mixed-grass/summer (68.4%) fires, and lowest in mixed-grass/winter fires (40.8%). Results suggest that summer fires or winter fires with high fuel loads are needed to achieve high seedling mortality. Winter fire effects in mixed-grass were diminished by green tissue in C 3 Texas wintergrass ( Nassella leucotricha ). Treatments with greatest mortality likely mimic fire-season and grass fuel conditions that existed prior to European settlement of the SGP and limited woody plant expansion.

Mercury (Hg), a global pollutant of widespread concern, poses significant threats to environmental and ecological health. Upland ecosystems are critical in the global Hg cycle, serving as major long-term sinks for atmospheric Hg, largely through vegetation mediated dry deposition. Despite this importance, substantial knowledge gaps remain on the global distribution patterns of Hg, particularly its more neurotoxic organic form, methylmercury (MeHg), in upland soils and the mechanisms governing its formation and fate. This review discusses current understanding of the global spatial pattern of Hg in upland soils and examines the controlling factors of Hg transformation under upland conditions. We propose that the pronounced spatial heterogeneity in soil Hg levels in upland ecosystems is primarily governed by macroscale drivers, including climate, topography, and vegetation type. Furthermore, the net MeHg concentration accumulated in surface soils is regulated by microscale biogeochemical and microbial processes, such as organic matter quantity and composition, redox dynamics and the microbial community structure. Here, we integrate nearly 50 existing published studies to investigate the distribution pattern of total Hg (THg) in upland soils and elucidates the drivers controlling the processes of methylation and demethylation, providing novel insight into Hg biogeochemical cycling in upland ecosystems and develops a conceptual foundation for future research aimed at assessing ecological risks and mitigating the impact of global Hg pollution.

Deep sand soils are inherently fragile with surface layers that are very low in organic matter and clay. Previous studies demonstrate that strategic deep tillage such as soil inversion and deep soil mixing can increase crop production on these soils in Southern Australia. However, the majority of the organic matter and nutrients are concentrated in the top organically stained layer and deep tillage incorporates 50–60 % of the organic layer into the subsoil below 200 mm. The physical composition of the soil (percentage of sand, silt, clay and organic matter) and the chemical properties of the soil (pH, nutrient levels, cation exchange capacity) can strongly influence the soil adsorption of trifluralin. Modest levels of organic matter and clay particles in the topsoil particularly following deep tillage equate to the scant attenuation of herbicides on sandy textured soils. Soil samples (0–100 mm) were collected from three experimental sites; two Arenic Solonetz soils near Esperance and one Arenic Arenosol soil near Geraldton in Western Australia. At all three sites, three experimental treatments were sampled; control (no tillage), deep mixed with a spader to 350 mm and soil inversion with a mouldboard plough to 350 mm. Soil samples were taken on two growing seasons post tillage at Geraldton, three post tillage at Esperance TJM and twelve post tillage at Esperance E1. Tillage reduced the measured soil-liquid partition coefficient (K d ) of trifluralin (p ≤ 0.05) at all three experimental sites. A greenhouse bioassay was developed to determine if soil changes from strategic tillage at one of the Esperance sites and the Geraldton site could be directly related to herbicide bioavailability at two of the experimental sites. Intact cores were used to maintain integrity of the field soils. Cores from both field sites demonstrated that soil inversion reduced the effective dose of trifluralin (p ≤ 0.01) for the bioassay species Lens culinaris. Together these experiments illustrate that strategic deep tillage can increase the bioavailability of trifluralin. These findings offer a valuable insight into the soil behaviour of trifluralin and can help farmers estimate the risk of phytotoxicity based on measurable soil characteristics. • Field experiments applied strategic deep tillage to 350 mm on Solonetz and Arensol sandplain soils. • Soil surface composition was substantially altered by redistribution of clay and organic matter. • The altered composition reduced the measured soil-liquid partition coefficient of trifluralin. • Bioassays confirmed that Strategic deep tillage increased trifluralin bioavailability.

Comparing 1-km Sentinel-1 surface soil moisture with coarser-resolution satellite data for agricultural drought monitoring in Mediterranean regions

Northern peatlands are critical carbon stores that are highly sensitive to hydrological conditions. Changes in these conditions, driven by climate change and land-use modifications, can even shift peatlands from carbon sinks to sources. Consequently, effective management of both natural and restored peatlands requires monitoring of hydrological parameters such as soil moisture. Recently launched hyperspectral satellites like EnMAP provide new capabilities for this monitoring through enhanced spectral resolution. This study presents a novel framework for estimating peatland soil moisture content by applying Continuous Wavelet Transform (CWT) with real-valued Morlet wavelet to EnMAP satellite data. We evaluated the performance of CWT-processed data against original EnMAP bands, multispectral Sentinel-2 data, and spectral moisture indices across nine peatland sites spanning hemiboreal, boreal, sub-Arctic, and Arctic zones in Finland, Sweden, and Estonia. The CWT-processed EnMAP model achieved the highest predictive accuracy (R 2 = 0.67, RMSE = 14.02%), followed by original EnMAP bands (R 2 = 0.50, RMSE = 17.23%), while Sentinel-2 bands showed substantially lower performance (R 2 = 0.32, RMSE = 20.09%) despite having finer spatial resolution. These results suggest that spectral resolution outweighs spatial resolution for peatland soil moisture estimation. Spectral moisture indices performed poorly with both satellite sensors (R 2 = 0.00–0.17), demonstrating the limitations of single band combinations compared to full spectral approaches. While spatial mismatch between ground measurements and satellite pixel size, along with limited hyperspectral data availability, constrained this study, our results demonstrate the potential of hyperspectral satellite data and CWT for peatland soil moisture monitoring. Future validation across diverse peatland types and restoration conditions would further strengthen these findings. • Ground reference data on peatland soil moisture from Finland, Sweden and Estonia • Continuous wavelet transform on hyperspectral satellite data for peatland moisture • Hyperspectral EnMAP outperforms multispectral Sentinel-2 for moisture estimation. • Spectral resolution outweighs spatial resolution for peatland moisture estimation.

Unveiling the hidden threat of chlorinated organic pollutants residual in anaerobic conditions: A regional multi-habitat perspective.

Water use plasticity and its drivers in Picea asperata forests across age classes and seasons on the southeastern Tibetan Plateau

Climatic characteristics, particularly temperature and ambient humidity, significantly affect the qualitative and quantitative indicators of flax production and fibre formation. Conventional technologies for obtaining flax fibre are based on natural dew retting, the efficiency of which depends on atmospheric moisture. The decrease in air humidity during summer periods due to climate change complicates the biological processes involved in the transformation of flax stems into retted straw. A separate harvesting technology involving low cutting of stems and their placement into windrows has been proposed to utilize productive soil moisture during retting and to accelerate seed harvesting. During field laying, windrows change their geometric parameters, become denser, and increase adhesion both between stems and with the soil surface, which requires periodic lifting and loosening. This paper presents the results of field experimental studies conducted using a developed experimental picker to determine rational structural and technological parameters based on a four-factor experimental design. Changes in windrow geometry and their interaction with the working elements of the picker were analysed. Optimal parameters of the picker for flax retting preparation were established. The study is aimed at developing a new technical solution for flax harvesting.

Conventional methods for treating potato starch processing wastewater (PSPW) are challenged by issues such as poor adaptability and high idle rates. Returning wastewater to the field, as a resource utilization strategy aimed at reducing pollutants and recovering nutrients, has emerged as a preferred approach for PSPW treatment. However, the unclear safe carrying capacity of soil in this process poses potential ecological risks. To scientifically evaluate the impact of repeated PSPW irrigation on soil safety performance, this study employed a soil infiltration system (SIS) to simulate the wastewater infiltration process. The results demonstrated that the SIS achieved average removal rates of 74.38%, 59.68%, 45.10%, and 77.94% for chemical oxygen demand (CODCr), total nitrogen (TN), ammonia nitrogen (NH4+-N), and total phosphorus (TP), respectively. Furthermore, multiple PSPW infiltrations led to weakly alkaline soil conditions and significant accumulation of organic matter, nitrogen, and phosphorus in the topsoil. Concurrently, the infiltration process altered the microbial community structure and reduced microbial diversity in the surface soil. The composition and function of the microbial community varied significantly with soil depth, with the community in the subsoil resembling that in the original, untreated soil. This study elucidates the patterns of pollutant removal during PSPW infiltration, the response of soil physicochemical properties, and the changes in microbial community structure at different soil depths. It provides a scientific basis for assessing the ecological impact of PSPW re-irrigation on soil and supports the potato industry in Northwest China in achieving green development goals.

Owing to rapid rainwater runoff and low surface soil moisture in karst environments, karst woody plants frequently experience drought and are highly vulnerable to climate change. However, recent studies have revealed that karst species can access reliable water sources from epikarst zones where have well-developed secondary porosity. The mechanisms by which woody plants cope with karst environments remains unclear. In this study, we established a stem and leaf hydraulic dataset for 696 karst and non-karst woody species (grown on soil substrates) from four climatic zones (tropical, subtropical, temperate, and Mediterranean), along with climate variables at each site. We aimed to address the following questions: How do karst and non-karst species differ in their hydraulic traits within the same climate? How do the hydraulic-climate relationships differ between the two plant groups? Our results showed that hydraulic efficiency, stem embolism resistance, and minimum leaf water potential were similar between karst and non-karst species in each climate zone. The stem hydraulic safety margin (HSMstem) was higher in karst species than in non-karst species in temperate and Mediterranean regions, but did not differ significantly in the other two climate zones. Leaf hydraulic safety-efficiency was significant and consistent between the two plant groups. However, at the stem level, the hydraulic trade-off was stronger in karst species than in non-karst species. Most hydraulic traits were significantly influenced by the aridity index in karst species, whereas in non-karst species leaf and stem hydraulic efficiencies were associated with the mean annual temperature and precipitation of the warmest quarter, respectively. With increasing aridity, HSMstem tended to increase in karst species but decrease in non-karst species. This comparative study enhances our understanding of the hydraulic strategies and drought risks associated with karst woody plants globally.

The ability of natural environmental sound to stimulate seeds and seedlings sufficiently to foster growth has not been previously demonstrated or quantified. To study this, rain sound is a logical starting point. Rain produces extremely high amplitude sound pressure with commensurate particle displacements in the upper soil, puddles and wetlands where many plant seeds germinate. Experiments were conducted with controlled rain drops impacting soil and shallow water puddles containing submerged seeds of rice (oryza sativa). Germination rates were measured as the peak sound pressure of drop impact was varied. The displacements of micro-meter-scale statoliths relative to the structure of specialized seed cells that sense gravitational direction were estimated as a function of the controlled rain sound forcing. The results here indicate rice and related seed types can sense the sound of rain impacting the soil or water surface above them and respond by accelerating germination at depths where impulsive rain sound is sufficiently intense to intermittently shake statoliths from contact with cell membrane receptors and trigger gravitropic growth mechanisms. The ability to perceive rain sound and respond with accelerated germination is found to be roughly limited to the relatively shallow depths that are also beneficial to seedling survival.

Surface water contamination by pesticides is intertwined to surface runoff and soil erosion from agricultural farms. This study determined the presence and levels of pesticide residue in water from Themi River which is a source of irrigation water at Fire vegetable farm located in Arusha, Tanzania. Using grabbing water sampling technique, three (3) composite samples of water were collected from three strategic locations along the Themi River. Applying liquid phase extraction method, the residual of three pesticides namely trichlorfon, dimethoate, and vamidothion were detected and quantified using Gas Chromatography Mass Spectrophotometer (GC-MS) Agilent 7890A with 2-20 ppm detection limit. Results shows that the concentration of trichlorfon in the water was averaged at 0.71±0.1 µg/l, dimethoate was at 1.64±0.31 µg/l while vamidothion was at 0.78±0.38 µg/l all exceeding the 0.1 µg/l International Union of Pure and Applied Chemistry (IUPAC) recommended limits for individual pesticides residual in irrigation water. Unsustainable application of pesticide in vegetable farms not only contaminates the river but also threatens environment, life below water and human health through trophic chain.

Phosphatic rock weathering and agricultural activities may pollute soils with potentially toxic elements (PTEs) in phosphate-rich regions. However, the behavior of PTEs during rock weathering and their subsequent fate under agricultural influence remain poorly understood. Therefore, the natural weathering profile and farmland soil in a typical phosphatic zone were selected as the subjects for investigating the behavior characteristics of PTE during weathering, as well as PTE bioavailability and sources in surface soil under the influence of agricultural activities. The investigation into natural weathered profiles demonstrated that the weathering of phosphatic rock could generate a significant geological background of cadmium (Cd), lead (Pb) and mercury (Hg) due to their geochemical fractions in minerals. The agricultural activities were associated with elevated levels and increased bioavailability of PTE, particularly lead (Pb), copper (Cu) and zinc (Zn). In farmland topsoil, mean Cd and Pb concentrations reached 0.86 and 151 mg/kg, respectively, with 87% and 70% of samples classified as seriously polluted. The correlation analysis indicated that iron oxide was the predominant controlling factor for the bioavailability of PTE in farmland soil. The results of sources based on Pb isotope and positive matrix factorization (PMF) model suggested that the presence of Cd and Pb in farmland soil was mainly caused by the pesticide use and fertilization, respectively, with PMF attributing approximately 81% and 74% of their totals to these anthropogenic sources. Our study reveals that severe PTE pollution in the phosphatic zone stems from the synergistic effects of natural rock weathering and agricultural activities. This research served as a valuable reference for the prevention and control of PTE in the phosphatic zone.

Impact of wildfire on the distribution and migration of plutonium and cesium isotopes in forest soils, Lu mountain, Sichuan.

Informal repair of used lead-acid batteries (ULABs) represent a significant yet poorly regulated source of heavy metal contamination in urban Indian. This study examined surface soils (0-5cm; n = 39) from ULAB repair sites across three cities in central India (Bhopal, Mandideep, and Chhindwara), with semi-urban controls (n = 5), quantifying 21 elements and evaluating human health risks using the USEPA framework. ULAB-affected soils showed extreme enrichment of Pb (median: 539.8mg/kg; IQR: 211.9-2421.3mg/kg; ~ 48-foldenrichment) and Sb (median:17.3mg/kg;IQR:5.5-39 mg/kg; ~ 29-foldenrichment), with moderate enrichment of Ag, Se, Zn, Cd, Cu, and As (~ 2.5-12-fold)relative to semi-urban control soils. Lithogenic elements showed minimal enrichment. Non-carcinogenic risk assessment indicated greater riskin children (hazard index, HI = 0.98),approaching the acceptable threshold, compared to adults (HI = 0.10), with Sb as the major contributor. Ingestion was the dominant exposure pathway, accounting for 88.6% of total exposure in children and 80.1% in adults. Although Pb lacks a reference dose, margin of exposure (MOE) analysis indicated very high risk in children (MOE = 0.08) and moderate risk in adults (MOE = 1.41). Lifetime carcinogenic risks from As, Cd, and Cr yielded total risks of 2.49 × 10⁻4 for children (exceeding the commonly accepted threshold of 1 × 10⁻4) and 2.67 × 10⁻5 for adults (within the acceptable range). Chromium dominated cancer risk despite low enrichment, reflecting its high toxic potency. Overall, informal ULAB repair activities generate distinct Pb and Sb co-contamination hotspots posing significant health risks, particularly for children, underscoring the need for targeted regulation and exposure mitigation.

Seasonal and diurnal variations in soil temperature play a critical role in baby corn production by influencing nutrient uptake and crop development. This study evaluated the effects of sowing windows, crop geometry and mulching on soil temperature dynamics and yield of baby corn. A field experiment was conducted at Tamil Nadu Agricultural University, Coimbatore, during the winter (January–April) and kharif (June–September) seasons of 2022 using a split-plot design with 3 replications. Results revealed that sowing windows, crop geometry and mulching significantly affected soil temperature at both the surface and sub-surface (15 cm depth) during both seasons. Late sowing (D₃) consistently recorded the highest surface soil temperatures (27.5–29.1 °C at 7:22 hr and 40.1–41.2 °C at 14:22 hr) during winter and kharif, followed by mid (D₂) and early sowing (D₁). Wider spacing (60 × 30 cm) without mulching resulted in higher surface and sub-surface soil temperatures compared to closer spacing and mulched treatments. Sub-surface soil temperature at 15 cm depth was also highest under late sowing and wider spacing without mulching across both seasons. Correlation analysis indicated a significant negative relationship between soil temperature and baby corn yield, with correlation coefficients ranging from -0.57* to -0.98** in winter and -0.60* to -0.94** in kharif 2022. The study demonstrates that appropriate adjustment of sowing time, crop geometry and mulching practices can effectively regulate soil temperature and enhance baby corn productivity under varying seasonal conditions.

The Changbai Mountain–Liaodong region is a crucial component of the global black soil belt in Northeast China and a significant national grain production base. However, like many high-latitude agricultural regions worldwide, it faces persistent challenges during the spring sowing period, including low soil temperatures and excessive moisture. Therefore, developing region-specific, effective methods of reducing soil moisture and increasing temperature while improving soil fertility is essential for improving agricultural productivity. To this aim, a field experiment was conducted with two factors: a main plot subjected to ridge tillage (RT) and flat tillage (FT) and subplots with biochar (BC) and straw (ST) amendments. A subplot with no amendment (CK) was used as a control. During maize growth, the daily soil temperature and moisture were monitored, and the soil water evaporation rates and physical structure, as well as the maize yield performance, were evaluated. The results showed that biochar and straw application significantly decreased the soil monthly water content by 1.69–2.22% (p < 0.05) in the surface soil layer (0–15 cm) from May to June, with a more pronounced effect under RT. In contrast, biochar application increased soil moisture and water storage from July to September, indicating that the influence of biochar on soil moisture depends on time and field aging processes. Biochar amendment raised the soil maximum temperature by 0.32–0.79 °C in the top 0–15 cm layer, while straw incorporation decreased the minimum soil temperature by 0.11–0.52 °C. The increase in soil temperature was primarily due to the biochar’s darker color, which facilitated solar radiation absorption, while the decrease in soil temperature was caused by the “Wind Leakage Effect” induced by the large particle size of the straw. Biochar and straw incorporation effectively enhanced maize dry matter accumulation by an average of 15.8% and 8.2%, respectively, and grain yield by 13.0% and 7.8%, respectively. Correlation analysis indicates that these increments are primarily due to enhanced soil moisture and available N content during the middle to late stages of maize growth. Therefore, the integration of straw and biochar with high-ridge cultivation is an effective strategy for excessive moisture reduction and warming in spring soil and it also contributes positively to maize yield.

A field experiment was conducted during the summer of 2019 and 2020 at the AICRP Water Management field, Tamil Nadu Agricultural University, Madurai. Tamil Nadu, India. To study the effect of coir pith application on soil moisture distribution with different irrigation regimes viz., I1 - Trickle irrigation of 120 % Pan Evaporation (PE), 100 % PE, and 80 % PE. Separately, maintained the surface irrigation of IW/CPE 1.20. The making of soil moisture slope is basic to investigate the gainful impacts through the use of coir substance and it very well may be conceivable to water holding capacity and spreading area of water distribution from the emitter of trickle irrigation system. Accordingly, formed raised beds manually with 90 cm top bed width and 30 cm furrow width. The well-composed coir pith @ 375 kg/ha was spread over the raised beds and leveled well with surface soil. The lateral was laid out in the center of each bed and paddy seeds (var CO-51) were dibbled manually at 20 × 10 cm spacing. Soil samples were collected in vertical and horizontal directions and determining soil moisture by gravimetric method. Soil moisture appropriation was plotted graphically as contour maps used by the surfer. Revealed, trickle irrigation at 120 % PE with coir pith application improved the growth and yield attributes of aerobic rice compared to surface irrigation (IW/CPE 1.20) due to coir pith has favorable hydrological and physical properties to hold and spread the water in the raised bed area of aerobic rice cultivation under trickle irrigation system.