To identify suitable soil amendments for the understory cultivation of Polygonatum kingianum and to address issues such as soil acidification, nutrient imbalance, and exacerbated soil-borne diseases resulting from continuous cropping of preceding Panax notoginseng, this study utilized two-year-old P. kingianum seedlings as experimental material. Three soil amendments—quicklime, wood ash, and tetramycinwere applied at three different concentration levels. After one year of planting, the yield, quality, and soil physicochemical properties of P. kingianum were measured to evaluate the effects of these amendments on agronomic traits, nutrient accumulation, and soil ecological and physicochemical characteristics. The results demonstrated that all tested amendments improved seedling survival rates and reduced the incidence of root rot in P. kingianum. All treatments effectively reduced the incidence of root rot in Polygonatum kingianum, with wood ash showing the greatest reduction (60%–80%), followed by quicklime (48%–72%) and tetramycin (58%–68%). A comprehensive evaluation using the entropy-weighted TOPSIS method indicated that all amendment treatments outperformed the untreated control group (CK). Among them, the wood ash C3 treatment (1200 kg hm-²) was the most effective, increasing yield by 51.96% compared to CK.
To evaluate the effects of maize straw return rate on soil mesofaunal community composition, diversity, and vertical distribution, four treatments were established: 0, 225, 450, and 900 g m⁻². In 2024, soil mesofauna and physicochemical properties were sampled at the maize seedling, jointing-tasseling, and pre-maturity stages from four soil depths (0–5, 5–10, 10–15, and 15–20 cm). A total of 8,122 individuals belonging to 20 taxa were identified. Dominant taxa were the suborders Oribatida, Mesostigmata, and Prostigmata, along with the family Onychiuridae, collectively accounting for 89.2% of total abundance. Straw return significantly increased mesofaunal abundance, species richness and Margalef’s richness (all p< 0.05), but not Shannon-Wiener diversity (p> 0.05). Pielou’s evenness index also responded significantly (p< 0.05). The Sørensen similarity coefficient was consistently lower than the Morisita-Horn index, indicating that straw return mainly altered less abundant taxa rather than the dominance pattern of major groups. Furthermore, straw return significantly enhanced the aggregation of mesofaunal abundance in the upper soil layer (0–5 cm). Canonical Correspondence Analysis revealed that soil organic matter and total potassium were the primary environmental drivers of community structure. Specifically, Onychiuridae was positively associated with pH, whereas Isotomidae and Hypogastruridae were linked to soil organic matter. Oribatida and Mesostigmata were positively associated with total potassium. Overall, the highest straw-return treatment (900 g m⁻²) showed greater mesofaunal abundance, richness and altered vertical distribution, correlated with variations in soil organic matter and total potassium.
Manganese (Mn) sorption plays an important role in controlling its mobility, bioavailability, and environmental behavior in calcareous soils. The current study examines the kinetics of manganese sorption in six calcareous soils sampled within the vertisols (Chromic Haploxererts) order in Duhok Governorate in Kurdistan Region, Iraq. A solution of manganese (MnSO4) 300 mg L-1 with 10 pore volumes (PV) at 298o K was added to soil. The findings indicate that the lowest Mn adsorption capacity was in the Imerik soil (1230.5) while Derabun soil having the highest value (1475.4 mg kg-1)by using miscible displacement technique. Mathematical description of Mn-adsorption according to kinetics approach gave the following best fitting: Power function, First order, Zero-order, Elovich equation, Parabolic equation, Second order, respectively, based on the highest R2 value and lowest SE. Rate coefficient of Mn adsorption ranges from (0.99 to 1) and (95 to 96) x 10-4 hr-1 with an average 96 x 10-4 hr-1 according to power function and First order, respectively. The physicochemical and mineralogical characteristics are reflected in variations of Mn adsorption in the investigated soils.
Saline-alkaline soil carbon reserve constitutes an important component of the terrestrial carbon pool; however, knowledge regarding soil organic carbon (SOC) stability in arid saline-alkaline loess remains limited. This study aimed to assess SOC stability by analyzing variations in organic carbon fractions and mineralization rates along a salinity gradient in the saline-alkaline loess of Middle Gansu Province, Northwest China; also the relationship between SOC stability and microbial diversity and community structure are discussed. The key results are as follows: (1) With increasing salinization levels, the diversity and abundance of bacterial and fungal communities significantly decreased, accompanied by marked shifts in microbial community structure. (2) Total carbon (TC) and SOC contents ranged from 12.19 to 32.00 mg g-1 and 6.58 to 14.31 mg g-1, respectively, while active organic carbon (AOC) and non-active organic carbon (NOC) contents varied between 1.44 to 5.57 mg g-1 and 3.46 to 9.12 mg g-1 —all of which showed a decreasing trend with escalating salinity. (3) After 40 days of incubation, the cumulative SOC mineralization in low, medium, and heavy saline-alkaline soils was 4833.77, 4287.74, and 3452.99 mg CO2 kg-1d-1, respectively, indicating that both the magnitude and rate of SOC mineralization declined progressively with increasing salinity. The carbon pool management index (CPMI) ranged from 0.73 to 2.17. Notably, the value of carbon pool management index (CPMI) was positively correlated with microbial community diversity and abundance (p < 0.051), indicating that SOC stability tends to be more stable with the decreasing microbial community diversity. These findings provide insights into the microbial mechanisms underlying changes in SOC stability in arid saline-alkaline loess.
Soil organic carbon (SOC) plays an important role in the global carbon cycle. However, there were few studies on SOC and its fraction of rhizosphere soil and bulk soil in the water-level fluctuation zone. Therefore, the study collected soil samples at three elevations (LP-145m, MP-155m and UP-165m) of four transects in the Pengxi River Nature Reserve. The contents of total SOC and its fractions (F1-very labile carbon; F2-inert carbon; F3-oxidizable resistant carbon) in bulk soil and rhizosphere soil were determined by using a modified Walkley-Black method. Results showed that content of total SOC, F1, F2 and F3 of rhizosphere soil at MP and UP were significantly higher than those of bulk soil, while there was no significant difference in SOC content between the two soil types at LP. The content of SOC fractions showed an upward trend with the increase of total SOC content, and the correlation coefficient with SOC was F2>F1>F3. F2 was the largest contributor to the total SOC content of rhizosphere soil in three altitudes, while in the bulk soil, the largest contributor was F2 at LP and MP and F3 at UP. In conclusion, the SOC content of rhizosphere soil was significantly higher than that of bulk soil at middle and high altitudes, and the F2 was the main contributor to the total SOC content.
To address the aggravated soil salinization and low productivity degrading farmland in Tianjin, the synergistic mechanisms of biochar and nitrogen fertilizer application for ameliorating such soils require elucidation. Based on this, the present study investigated the effects of combined biochar and nitrogen fertilizer application on nitrogen-fixing microorganisms and mineral nutrients in saline-alkali soil by establishing four treatments: Low concentrations of nitrogen fertilizer (H1), biochar plus low concentrations of nitrogen fertilizer (NH1), high concentrations of nitrogen fertilizer (H2), and biochar plus high concentrations of nitrogen fertilizer (NH2). The results showed that the combined applications of biochar and different concentrations of nitrogen fertilizer had significant effects on the nitrogen-fixing microorganisms in maize rhizosphere. Biochar application increased the abundance and Operational Taxonomic Unit（OTU）number of nitrogen-fixing microorganisms in maize rhizosphere, which was specifically shown as NH2 > H2 > NH1 > H1. The Shannon and Simpson indices indicate that the combined application of biochar and nitrogen fertilizer enhances the diversity of soil nitrogen-fixing microorganisms. Biochar application increased the content levels of available potassium and available phosphorus in maize rhizosphere soil. Increasing the application of nitrogen fertilizer significantly increased the urease, alkaline phosphatase and sucrase activity in the soil. The combined applications of biochar and nitrogen fertilizer increased the yields of the maize and the thousand-seed weight. The maize yields and thousand-seed weight of the NH2 treatment were 29% and 16% higher than that of the H1 treatment, respectively. In conclusion, this study determined that for salinized cultivated soil, combined applications of biochar and nitrogen fertilizer can improve the diversity of soil nitrogen- fixing microorganisms, improve soil micro-environment, and increase maize yield, which are conducive to the improvement and fertilization of saline soil.
Industrial wastewater generated by tire manufacturing plants contains complex mixtures of organic chemicals, heavy metals, and inorganic salts that pose serious environmental risks if discharged without adequate treatment. Despite the well-documented hazards of such effluents globally, data on their physicochemical and microbiological characteristics in Iraq remain scarce. This study aimed to characterize the physicochemical properties and heavy metal contamination of wastewater from a tire manufacturing plant in Al-Diwaniyah, Iraq, and to identify indigenous bacterial species with potential bioremediation relevance. Wastewater samples were collected monthly from May to October 2025 at three designated sampling points. Physicochemical parameters including pH, electrical conductivity (EC), salinity, total dissolved solids (TDS), nitrate, sulfate, phosphate, chloride, and chemical oxygen demand (COD) were measured using standard APHA methods. Heavy metals (Pb, Cd, Ni, Zn, Cu) were quantified by atomic absorption spectrophotometry (AAS). Indigenous bacteria were isolated and subjected to Gram staining, Vitek-2 identification, and confirmation by 16S rRNA gene sequencing with phylogenetic analysis. Statistical analysis included one-way ANOVA and Pearson correlation. Results revealed substantial temporal variability: pH ranged from 6.8 to 9.5, EC from 597 to 2792 & micro;S cm-1, TDS from 1032 to 2717 mg L-1, and COD up to 531 mg L-1. Heavy metal concentrations frequently exceeded Iraqi and WHO discharge limits, particularly for Zn (2.09-5.18 mg L-1) and Ni and B. persicus, with 97-99% 16S rRNA gene similarity to NCBI reference sequences. The identified Bacillus species exhibit known adaptations to extreme and pollutant-laden environments, suggesting their candidacy for future bioremediation strategies; however, direct experimental validation of pollutant removal capacity is required before practical applications can be claimed.
Mountain highlands in tropical regions contribute to cultivation and buffer zones, however, these areas are vulnerable to soil degradation. For this reason, soil quality evaluation is necessary to assess the area's ability to maintain its function. This study aims to analyze the distribution of soil quality index (SQI), identify the determining factor, and formulate recommendations for land management. This research was conducted in Poncol Sub-district, which is part of the Mount Lawu highland of Indonesia. Overlaying sources of variation of land use, slope, rainfall, and soil type resulted in 12 Land Map Units (LMUs), each repeated 3 times, thus resulting in 36 sampling points. Soil quality was determined using the SQI method based on Principal Component Analysis (PCA) of soil properties. The effect of sources of variation on SQI and the identification of determining factors were analyzed statistically. The results showed that the SQI across all LMU was classified as low to moderate. Land use, slope, and rainfall significantly influenced the SQI, with the highest values found in forest land use. The relatively high SQI at slopes of 25-45% were closely related to the dominance of forest land use in that slope class. The SQI was highly correlated with bulk density, porosity, soil organic carbon, base saturation, available P, and total N, which were identified as the main determinants of SQI. These findings confirm that soil quality improvement is still needed in all land use systems, including forests, to support their function, particularly as sustainable environmental buffer zones. Soil quality in agricultural land uses (plantations, crop fields, paddy fields) can be improved through management that focuses on increasing C-organic.
Soil chemical properties in tidal ecosystems are influenced by tidal dynamics, river inputs, and water management. Understanding how these properties vary with distance from the river is essential for effective soil and water management. Therefore, this study evaluated variations in soil chemical characteristics along a riverdistance gradient within a fork-type irrigation system in the tidal ecosystem of Belawang District, South Kalimantan, Indonesia. Soil samples were collected from six distances (200-12,200 m) from the Barito River at a depth of 0-25 cm and analyzed for pH, organic carbon (C), total nitrogen (N), phosphorus (P), and potassium (K), exchangeable aluminum (Al3+), and hydrogen (H+). Pearson correlation and regression analyses were used to assess relationships between soil chemical properties and distance from the river. Increasing distance from the river significantly reduced soil pH, organic C, and total N, while exchangeable Al increased markedly. Total P and K also declined with distance, although their relationships were weaker. These patterns suggest that reduced tidal influence and buffering capacity in distal areas promote soil acidification. River proximity, therefore, plays a critical role in regulating soil chemical properties in tidal swamp ecosystems, emphasizing the need for integrated water and soil management to sustain soil fertility in distal tidal lands.
Conventional random sampling methods are inappropriate for comprehensive soil characterization and for generating high-resolution datasets. Therefore, microscale assessment of soil characteristics is imperative for monitoring soil conditions and implementing site-specific practices. The objectives of this study were to predict the physicochemical attributes of soil on a 50-hectare farm area by evaluating and categorizing spatial variability using geostatistical models and digital soil maps (DSM). The study area is at University Research Farm (URF), Koont, tehsil Gujar Khan, district Rawalpindi, Pakistan. It lies within the GPS coordinates of longitude from 73°0’45” E to 73°1’15” E and latitude from 33°6’45” N to 33°7’15” N. The farmland has sandy clay loam soil texture, and belongs to the Chakwal soil series and the Aridisols order of soil taxonomy. In the first phase of this study, 800 soil samples (0-15 cm deep) were collected from a 50-hectare farm area using a 25 m × 25 m grid defined by the Global Positioning System (GPS). In the second phase, a large dataset was acquired through wet-chemical analysis of soil properties, including the pH, EC, and contents of soil organic matter (SOM), NO3-N, available-P, and extractable-K. During the third phase, spatial microvariability was assessed through descriptive statistics parameters (SD, CV, and skewness). Data showed greater differences among the soil samples for SOM, NO3-N, and available-P contents, which were in the lower range. At the final stage, spatial interpolation was performed using semivariogram modeling and kriging to create the DSM. Chemometric analysis revealed that the best-fitted models were exponential for SOM, spherical for pH and EC, rational quadratic for NO3-N, penta-spherical for P, and circular for K. Nugget-to-sill ratio (N/S) for SOM and K contents revealed strong spatial dependence; whereas, for pH, EC, NO3-N, and available-P, it was moderate. The RMSE values < 1.0 for pH, EC, SOM, and NO3-N indicate the best-fit semivariogram models. In the DSM, most of the fields appeared normal with respect to pH and EC values. The SOM and NPK contents were displayed in the very low and medium ranges, covering >50 % of the total area. These findings establish that digital mapping is appropriate for assessing the soil properties in larger areas. In conclusion, the geostatistical modeling and DSM together facilitate soil characterization and prediction of soil attributes to categorize the large farm area into distinct soil management zones.
The application of urea-based fertilizers in water-saturated soils represents a significant source of greenhouse gas (GHG) emissions, particularly nitrous oxide (N2O). This study evaluated the effects of zeolite-based slow-release urea combined with nitrification inhibitors on methane (CH4), carbon dioxide (CO2), and N2O emissions, as well as nitrogen transformation and soil microbial populations under saturated conditions. A 49-day laboratory incubation experiment was conducted using five treatments: control (no nitrogen), granulated urea (U), urea + zeolite (UZ), urea + zeolite + neem (UZN), and urea + zeolite + dicyandiamide (UZD). Methane emissions declined rapidly after 14 days and remained low across all treatments, indicating dominant methane oxidation under saturated conditions. Zeolite-amended treatments increased CO2 emissions, likely due to enhanced microbial respiration. Notably, the UZD treatment significantly reduced N2O emissions compared to other urea treatments, while maintaining higher ammonium (NH4+) and lower nitrate (NO3-) concentrations throughout the incubation period. The reduction in N2O emissions was not associated with changes in nitrite-oxidizing bacterial populations but rather with inhibition of ammonia monooxygenase (AMO), thereby suppressing nitrification and reduced substrate availability for N2O emissions. These findings indicate that process-based controls on nitrogen transformation are more critical than microbial population size in regulating N2O emissions. In contrast, neem-based treatments showed less consistent mitigation effects. Overall, the results demonstrate that combining zeolite-based slow-release urea with dicyandiamide is an effective strategy for mitigating N2O emissions under saturated soil conditions. However, fieldscale validation is required to confirm these findings under natural agricultural conditions.
Chemical fertilizers degrade the environment, while organic fertilizers limit yields, but their combined application offers a sustainable solution in terms of environmental issues and crop yields. This study evaluates the combined effects of organic and chemical fertilizers on wheat growth, yield, soil health, and economic returns, aiming for sustainable agricultural practices. A randomized complete block design examined 13 treatments, including chemical fertilizer (RDF), organic fertilizers-general compost (GC), trichoderma compost (TC), vermicompost (VC), cow dung (CD) and their combinations at varying doses, each replicated thrice. Results indicated that the combined application of 75% RDF with 2.5 t ha(-1) vermicompost (T-4) significantly enhanced plant height, chlorophyll content, and yield components, achieving the highest grain yield (47.77 g plant(-1)), straw yield (51.14 g plant(-1)), and biological yield. Post-harvest soil analyses revealed that organic and integrated treatments significantly increased soil nitrogen (up to 0.16%), phosphorus (0.15 mg kg(-1)), sulfur (8.2 mg kg(-1)), potassium (97.75 mg kg(-1)), and organic matter (up to 2.1%) compared to inorganic-only treatments. Economically, the highest net return (Tk 74,735) was recorded in T-4, with a benefit-cost ratio (BCR) of 1.67, while sole organic treatments resulted in losses. The findings suggest that integrating 75% RDF with vermicompost optimizes wheat yield, enhances soil nutrient status, and offers an environmentally sustainable alternative to sole chemical fertilization.
Thymus vulgaris L. is an aromatic plant that improves nutrient use efficiency and plant development. Research was conducted to evaluate the effect of biostimulants on photosynthetic, nutritional, phytochemical, gas exchange, antioxidant properties of thyme and different analyses of soil. Different concentrations of moringa leaf extract (MLE) variety name Moringa oleifera, brassica water extract (BWE) variety Brassica napus, and sorghum water extract (SWE) sorghum variety locally known as jawar (1%, 2%, and 3%) of each were used. These treatments were applied three times after 15 days interval and data were collected. Randomized complete block design (RCBD) was used to organize the experiment. The physiological, biochemical, antioxidant, and soil characteristics of thyme were significantly enhanced by the application of biostimulants. Chlorophyll, carotenoids, proteins, flavonoids, anthocyanin, antioxidant enzyme activities, and soil nutrient concentrations were all significantly increased by MLE at 3% concentration, which had the most noticeable impacts of all the treatments. In the same way, as compared to the control treatment, BWE and SWE at 3% concentrations enhanced plant growth characteristics, phytochemical components, antioxidant activities, and soil nutrient parameters. Overall, the results show that natural biostimulants have a good impact on soil health and plant performance, with MLE showing the greatest efficacy. It is concluded that 3% MLE, BWE, SWE significantly enhanced the photosynthetic, nutritional, phytochemical and antioxidant properties of the Thymus vulgaris plant and improved analyses of soil. Future scope recommended exploring their potential integration into sustainable agriculture practices for enhanced crop productivity and soil fertility.
The Aral Sea region has experienced severe environmental degradation due to increasing salinity, desertification, and a significant decline in water resources. These processes have led to the accumulation of toxic salts in soils, negatively affecting ecosystem stability and agricultural productivity. This study evaluates the potential of the drought-and salt-tolerant tropical plant Crotalaria juncea L. as a sustainable solution for rehabilitating saline and degraded lands. Field experiments were conducted to assess the effects of seed treatment with Geohumate stimulant and the application of liquid fertilizer (NPK 20%) at a rate of 1.5 kg ha-1 during the budding and flowering stages. Soil samples were collected from depths of 0-30 cm and 30-50 cm to determine changes in salt composition. The results showed a reduction in major salt components, including Ca(HCO3)2 (0.008-0.010%), CaSO4 (0.062-0.050%), Na2SO4 (0.125-0.083%), NaCl (0.018-0.004%), MgSO4 (0.036-0.030%), and MgCl2 (0.034-0.037%). The total salt content decreased from 0.283 to 0.226 mg kg-1, representing a significant reduction of 10.3-10.4% in toxic salts. Additionally, the establishment of Crotalaria juncea improved vegetation cover, enhanced soil moisture retention, and contributed to the stabilization of desert grassland ecosystems. These findings demonstrate that integrating salt-tolerant crops with appropriate agronomic practices can effectively reduce soil salinity and support ecological restoration in arid and saline environments. This approach offers a promising, nature-based solution for mitigating land degradation in the Aral Sea region.
Through its commercial forestryplantations, Langeni Forest contributes to the economy of the Eastern Cape province, South Africa. However, forestry production has the potential to change the chemical characteristics of the soil. As a result, this study investigated the impact of indigenous forest, Eucalyptus and pine plantations on concentrations and composition of soil properties. Additionally, we compared the concentrations of soil properties between the surface and deeper layers of each forest type. Fifteen sampling stations were selected, five in each forest type. At each station, sampling occurred at 0-15 cm (surface layer) and 16-30 cm (deeper layer). Our study showed that the calcium, magnesium and phosphorus in Eucalyptus forest, magnesium in pine forest, and potassium in indigenous forest were concentrated in the surface than in the deeper layers. However, in indigenous forest calcium concentration was higher in the deeper than the surface layers. Furthermore, we showed that the effect of forest type on soil properties is pronounced in the deeper layer than in the surface soil layer. Results from the surface layer showed that forest type affected concentrations of calcium and magnesium, while in the deeper layer, forest type affected concentrations of calcium, magnesium, potassium, and zinc. These results can be explained by the vertical distribution of nutrients, and characteristics of the leaf litter in each forest type, with broadleaved indigenous and Eucalyptus forests decomposing faster than pine needles. Thus, for most nutrients, greater concentrations of nutrients were recorded in Eucalyptus and indigenous forest than in pine forest.
One of the major pathways for human intake of potentially toxic elements (PTEs) in developing countries is through food. In Pakistan, untreated municipal effluent is a primary source of PTEs contamination in sewage-irrigated crops. This study was designed to assess the adverse effects of PTEs, particularly cadmium (Cd) and lead (Pb) through contaminated crops. Cadmium (Cd) and lead (Pb) concentrations were analyzed across the soil-water-crop continuum at three sites in Chiniot District: canal water irrigated (site 1), sewage irrigated (site 2), and historically sewage irrigated (site 3). The daily intake of metals (DIM) and health risk index (HRI) were calculated based on crop consumption. In leafy vegetables such as spinach, Cd and Pb levels at site 2 increased by 164.7% and 110.1%, respectively, relative to site 1. The highest Cd concentration was recorded in spinach at site 2 (0.45 mg & centerdot;kg(-1)), while the lowest was found in zucchini at site 1 (0.036 mg & centerdot;kg(-1)). Pb levels peaked in spinach at site 2 (1.2 mg & centerdot;kg(-1)) and were lowest in corn at site 1 (0.11 mg & centerdot;kg(-1)). Average DIM (mg kg(-1) day(-1)) values across all sites ranged from: Cd (adult): 2.56 & times;10(-5) to 8.47 & times;10(-5), Cd (child): 3.76 & times;10(-5) to 1.25 & times;10(-4), Pb (adult): 7.66 & times;10(-5) to 1.96 & times;10(-4), Pb (child): 1.12 & times;10(-4) to 1.96 & times; 10(-4). Corresponding HRI values were: Cd (adult): 2.55 & times;10(-2) to 8.47 & times;10(-2), Cd (child): 3.76 & times;10(-2) to 1.24 & times;10(-1), Pb (adult): 1.91 & times;10(-2) to 4.91 & times;10(-2), Pb (child): 2.82 & times;10(-2) to 7.32 & times;10(-2). As all HRI values remained safe below 1, indicating no immediate health risk but it is imperative to address the elevated levels of Cd and Pb in crops.
Soil contamination by dyes, pharmaceuticals, and hydrocarbons poses a significant environmental challenge, requiring sustainable remediation strategies. In this study, four indigenous fungal strains-Psilocybe sp. (FK01), Schizophyllum sp. (FK02), Trichoderma sp. (FK03), and Aspergillus sp. (FK04) were isolated from diverse ecological niches for potential use in soil mycoremediation. Isolation was carried out using serial dilution and direct plating methods and the strains were subsequently cultured on Potato Dextrose Agar (PDA) medium supplemented with antibiotics. Pure cultures were obtained through repeated subculturing and monospore isolation. Fungal identification was based on macro-morphological characteristics, including colony morphology, pigmentation, growth patterns, and microscopic structures (hyphae, conidiophores, and phialides). Observations were performed using optical microscopy (400x-1000x) after lactophenol cotton blue staining. Enzymatic activities (catalase, protease, amylase, and manganese peroxidase) were evaluated on solid media with corresponding substrates, while laccase activity was measured spectrophotometrically using ABTS at 420 nm. Biodegradation efficiency was assessed under controlled conditions by monitoring pollutant absorbance over 20-60 min. Schizophyllum sp. (FK02) achieved the highest degradation (similar to 47% at 40 min), followed by Trichoderma sp. (similar to 36-45%), Psilocybe sp. (similar to 10-25%), and Aspergillus sp. showing variable activity. Precolonized cereal-grain substrates improved fungal survival and activity compared to sawdust, maintaining viability for up to three weeks in soil. These results demonstrate, through multivariate analysis, that the selection of specific fungal strains and the optimization of inoculum delivery systems significantly enhance the effectiveness of in situ bioremediation of contaminated soils.
Cotton is a cash crop of arid to semiarid regions, and the present study investigates the integration of biofertilizers with organic amendments and balanced NPK for improving cotton growth, yields, nutritional quality, antioxidant status and soil health. Two local cotton varieties (SS32 and CK9) were evaluated in a completely randomized design (CRD) with three replications in pots. Treatments include control, recommended NPK, compost, poultry manure, biofertilizer +NPK, biofertilizer +compost +NPK and biofertilizer +poultry manure +NPK. The results revealed a significant improvement in cotton growth, nutritional and yield attributes viz., shoot length by 26 and 29%, root length by 28 and 29%, seed cotton yield by 28 and 34%, lint yield by 32 and 38%, shoot nitrogen by 26 and 32%, phosphorus by 31 and 33%, K by 26 and 29%, Zn by 33 and 34% and Fe by 27 and 34% under CK9 and SS32, respectively, by biofertilizer +compost +NPK treatment compared to control. Same treatment also improved microbial biomass carbon (MBC) by 45% and 43%, and CFU by 36% and 28%, under the CK9 and SS32 varieties, respectively. It can be concluded that integrating different nutrient sources offers sustainable cotton production while improving soil quality.
Subsurface drip irrigation (SDI) is an efficient irrigation method widely used in arid and semi-arid regions; however, its effectiveness largely depends on soil physical properties and the resulting soil water distribution. This study investigated soil wetting pattern dynamics under SDI and developed empirical models to predict wetted soil geometry as influenced by emitter discharge, installation depth, irrigation time, soil texture, and bulk density. Laboratory experiments were conducted using two representative soils from the Kurdistan Region of Iraq (Semel- silty clay and Zakho-clay loam). Emitters with discharge rates of 2 and 4 L h-1 were installed at depths of 12.5, 25, and 37.5 cm, and equal water volumes (8 L) were applied to monitor the advancement of the wetting front. Nonlinear regression models were developed to estimate maximum horizontal wetted diameter (H) and average vertical wetted depth (V) as functions of emitter discharge (q), irrigation time (t), clay content (c), and bulk density (rho b). The models showed strong predictive performance, with coefficients of determination (R2) ranging from 0.87 to 0.98. Model validation indicated acceptable accuracy, with root mean square error (RMSE) values of 1.676-5.033 cm, mean absolute error (MAE) of 4.531-10.745 cm, and mean absolute percentage error (MAPE) of 5.468-10.613%. The index of agreement (d) ranged from 0.968 to 0.995, while mean bias error (MBE) values were close to zero, indicating minimal systematic error. The results demonstrated that wetting front expansion was primarily governed by irrigation time, whereas emitter discharge had a comparatively smaller influence, particularly at shallow depths. Increased clay content reduced both horizontal and vertical wetting dimensions, while the effect of bulk density varied with emitter depth. Lower discharge applied over longer durations enhanced lateral water movement, whereas higher discharge promoted vertical flow and deep percolation. The developed models provide practical tools for predicting soil water distribution and can support the optimization of emitter spacing, irrigation scheduling, and water-use efficiency in SDI systems under semi-arid conditions.
Mountainous terrain imposes major constraints on agricultural land use by increasing erosion risk and limiting cultivation potential. This study assessed agricultural land capability and suitability in Kamenica Municipality, eastern Kosovo, using an integrated framework combining soil survey, World Reference Base suitability evaluation, and multivariate statistical analysis. A total of 135 representative soil profiles were described and analyzed, with particular emphasis on slope gradient and effective soil depth as the principal limiting factors. Luvisols, Cambisols, and Umbrisols together cover 83.1% of the municipality. However, agricultural potential is strongly constrained by terrain morphology: Classes VI-VII account for 46.9% of the area, whereas high-capability land (Classes I-II) occupies only 4.5%. Suitability analysis further shows that 58.6% of the land is not suitable for rainfed crops and 84.7% is not suitable for irrigated crops, while grazing displays the broadest suitability, with 51.8% of the area classified as moderately suitable. These findings indicate that agricultural planning in mountainous regions should prioritize land uses compatible with terrain and soil limitations, particularly extensive grazing and conservation-oriented management.
