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Soil salinity and drought are major environmental challenges that significantly affect soil functioning and soil organic matter (SOM) decomposition. Despite their importance, the combined effects of drought and salinity on residue decomposition are not well understood. This study addresses this gap by evaluating the decomposition of maize residue under salinity and drought stresses over a 75-day incubation period at 20 °C under controlled conditions. The experiment included two moisture levels: optimum moisture at 80% water-holding capacity (WHC) and drought conditions at 30% WHC, in both normal (ECe = 1.48 dS m−1) and saline (ECe = 8 dS m−1) soils, with 5 g DM kg−1 soil maize residues mixed in. A control treatment without maize residue addition was also included. The results indicated that salinity stress reduced maize residue decomposition, as evidenced by lower soil respiration, decay constant, metabolic quotient (qCO2), and soil extracellular enzyme activities. While drought did not affect total soil respiration in the presence of maize residue, it significantly decreased soil extracellular enzyme activities and decay constant rates. Combined drought and salinity stress further diminished maize residue decomposition, marked by reduced soil respiration, decay constant, microbial biomass carbon, and soil extracellular enzyme activities, while dissolved organic carbon (DOC) and qCO2 increased significantly. Similarly, extracellular enzyme activities were significantly reduced under abiotic stresses and further diminished under combined stress conditions. In conclusion, the simultaneous occurrence of drought and salinity can have compounded detrimental effects on microbial functioning, particularly in the presence of fresh plant residues. [ABSTRACT FROM AUTHOR]

An incubation study investigated the decomposition patterns, microbial activities, soil aggregates distribution, and soil organic carbon (SOC) contents, using four crop residues; wheat (Triticum aestivum L.), rice (Oryza sativa L.), cotton (Gossypium hirsutum L.), and maize (Zea mays L.), at low and high rates (10 and 20 g kg-1). An average increase of about 35% in cumulative C-CO2 emissions and 26% in soil microbial biomass carbon (MBC) was observed at high residue rates as compared to low rates. A positiv e and strong correlation (0.96) was found between C-CO2 emissions and MBC, and the effect of residue quality on decomposition was found to be less at high rates. The relative reduction in C-CO2 emissions by adding rice residues may be due to their high silica content. Differences in extracellular enzyme activities (EEA) with different residues indicated the effect of residue quality on microbial activities. Cotton residues increased β-glucosidase and chitinase activities by 41 and 38%, respectively, at high rates than at low rates. High maize residues also markedly increased chitinase activity by 41%, implying higher N cycling and fungal prevalence. Acid phosphatase activity was found to increase by about 25 to 32% with high rice and wheat residues, respecti vely. Higher EEA at high residues input likely reflected the microbial nutritional limitations. Crop residues raised SOC content from 0.7 under control to 1.0% at low residues input but not at high input. Increased macro-aggregates fraction at high residues input may be attributed to higher microbial activities. In summary, high residues input can minimize residue biochemical quality's effect on decomposition, with no further increase in SOC content. While a positive effect on the soil MBC, but not on the SOC content, was observed at high residue input, suggesting moderation in the additions of organic amendments is key for SOC buildup. Crop residues, added at 10 g kg-1, may help maintain a positive SOC balance in the arid agroecosystems by moderating higher microbial activities and soil respiration. [ABSTRACT FROM AUTHOR]

The fate of agriculture in Pakistan is predominantly concerned with excessive water mining threats to the subsurface water resources. The current study integrates the Visual MODFLOW-2000 application to estimate the water balance of an aquifer bounded by the Chenab River in the West and the Ravi River in the East, which covers an area of about 2.98 million hectares. An assimilated method of groundwater flow is employed to characterize the flow dynamics of the Rechna Doab aquifer. The Digital Elevation Model (DEM) produced by the Shuttle Radar Topography Mission (SRTM) and a mesh of discretized cell size (2500 m) were incorporated into the model design. The conceptual model of the alluvial aquifer involves trifold vertical boundaries (an initial fold thickness set up to 150 m). The model input parameters are precipitation, seepage through irrigation, return flow, recharge, hydraulic conductivity and evapotranspiration. Empirical relations are established (at the basin scale) for the discharge input of irrigation canals. Model results confirm that groundwater flow follows the topographic configuration of the study area (i.e., northeast to southwest), and the seepage from irrigating canals and rainfall appeared to be the main source of groundwater recharge among various resources. The zone budget study under steady state simulation showed that the total direct recharge to the aquifer is calculated as 522,910 acre foot. The simulated water balance of the studied aquifer reflects more fluctuations in river leakage. The predictive optimized model reflects an adaptation of canal lining and installation of additional tube wells that will minimize canal seepage by 70% and lead to the reclamation of 37,000 acres of water-logged land for normal cropping. [ABSTRACT FROM AUTHOR]

OBJECTIVE: To compare the quadriceps isokinetic strength parameters of athletes and non-athletes. METHODOLOGY: The cross-sectional study was conducted from July to December 2019 at the Pakistan Sports Board, Islamabad. The sample size was 81, selected through a non-probability convenience sampling technique and calculated by the Rao Soft tool. The 41 participants were in the athletes' group, and 40 were in the non-athletes' group. Individuals with a history of sprain, strain, or fracture in the lower limbs within the last six months were excluded. The self-structured questionnaire includes demographic data, waist-to-hip ratio, thigh circumference, peak torque values and agility t-test score. The isokinetic strength of the right lower limb (RLL) was measured via Biodex system Pro 3. Data was analyzed through SPSS 22, and an independent t-test was applied for analysis between groups. Pearson test was used for the correlation coefficient. RESULTS: Athletes had significantly higher quadriceps muscle strength than non-athletes (p<0.001), indicating the positive impact of regular sports participation and physical training. Quadriceps peak torque positively correlated with thigh circumference (r=0.60, p<0.001), consistent with previous studies. Surprisingly, athletes exhibited a weak to moderate negative correlation between quadriceps peak torque and agility (r=-0.35, p<0.05), suggesting a potential trade-off between muscle mass and agility performance. Increased muscle bulk may compromise speed and flexibility. CONCLUSION: Athletes demonstrated superior quadriceps muscle strength, emphasizing the positive influence of sports involvement and physical training; thigh circumference positively correlated with Quadriceps peak torque, and Agility negatively correlated with quadriceps peak torque. [ABSTRACT FROM AUTHOR]

This study proposes an adaptive image augmentation scheme using deep reinforcement learning (DRL) to improve the performance of a deep learningbased automated optical inspection system. The study addresses the challenge of inconsistency in the performance of single image augmentation methods. It introduces a DRL algorithm, DQN, to select the most suitable augmentation method for each image. The proposed approach extracts geometric and pixel indicators to form states, and uses DeepLab-v3+ model to verify the augmented images and generate rewards. Image augmentation methods are treated as actions, and the DQN algorithm selects the best methods based on the images and segmentation model. The study demonstrates that the proposed framework outperforms any single image augmentation method and achieves better segmentation performance than other semantic segmentation models. The framework has practical implications for developing more accurate and robust automated optical inspection systems, critical for ensuring product quality in various industries. Future research can explore the generalizability and scalability of the proposed framework to other domains and applications. [ABSTRACT FROM AUTHOR]

Salt stress is a major problem at the global level and it is very important to utilize salt-affected soils using appropriate techniques. Growing halophytes on saline-sodic soil is a win-win strategy for getting economic crop production and conservation of soil resources. However, it is prerequisite to identify the cultivars which can be recommended for salt-affected soils considering physiological and biochemical responses under salt-stress. Therefore, sugar beet cultivars were characterized at seedling stage based on growth, physiological and biochemical parameters under different levels of salt stress. A hydroponic experiment was conducted using eight sugar beet cultivars (AMALDI, GELLERT, VANGELIS, VEDA, WYNNYK, SERENADA, CALIFORNIA and ALBINA VEREDUANA) and two salt stress levels (60 and 120 mM NaCl) in comparison with that of an untreated control. The plants were harvested ten days after giving salt stress. Cluster dendrogram and principal component analysis were the most appropriate methods for screening the suitable cultivar. Most of the sugar beet cultivars responded as resistant against salt stress, however, VEDA cultivar performed best against it. Thus, VEDA cultivar acquired highest position at 60 mM NaCl showing 6.4% plant biomass improvement as compared to control, while 2.1% reduction was recorded at 120 mM NaCl as compared to 60 mM NaCl. Additionally, this cultivar showed highest growth attributes, antioxidant activity with higher K+/Na+ ratio, hydrogen peroxide, phenolic and malondialdehyde content, indicating strong defense mechanism against salt induced oxidative and osmotic stress mainly owing to the best K+ and Na+ balance. It is concluded from this study that VEDA is the best salt-resistant cultivar with great potential to be grown on salt-affected soils and can be proceeded for field trials at various salt-stress levels. [ABSTRACT FROM AUTHOR]

Cognitive Radio Network (CRN) has turn up to solve the issue of spectrum congestion occurred due to the wide spread usage of wireless applications for 6G based Internet of Things (IoT) network. The Secondary Users (SUs) are allowed to access dynamically the frequency channels owned by the Primary Users (PUs). In this paper, we focus the matter of contention of routing in multi hops setup by the SUs for a known destination in the presence of PUs. The traffic model for routing is generated on the basis of Poison Process of Markov Model. Every SU requires to reduce the end-to-end delay and packet loss of its transmission simultaneously to improve the data rate for the Quality of Service (QoS) of the Secondary Users. The issue of routing is formulated as stochastic learning process of non-cooperative games for the transformation of routing decisions of SUs. We propose a distributed non-cooperated reinforcement learning based solution for solving the issue of dynamic routing that can avert user interferences and channel interferences between the competing Sus in 6G-IoT network. The proposed solution combines and simulate the results to show the effectiveness and working of the proposed solution in decreasing the end-to-end delay, packet loss while meeting the average data rate requirement of QoS for SUs. [ABSTRACT FROM AUTHOR]

Increasing frequency of droughts and problems related to salinization in irrigated areas may directly affect soil biological functions and soil respiration. An incubation study was designed to elucidate the effects of salinity and water intercross stresses on soil respiration and microbial activities. Three different moisture levels: optimum moisture conditions (80% water holding capacity (WHC)), moderate drought (50% WHC) and severe drought stress (30% WHC) were maintained in normal (ECe=1.48 dS m-1) and saline (ECe=8 dS m-1) soils. Our results showed that drought stress resulted in significant increase (p < 0.05) in microbial biomass carbon (MBC) (601+79 mg C kg-1 soil) and cumulative C-CO2 emissions (1153+96 mg C kg-1 soil). While under drought stress, extracellular enzyme activities showed no significant difference except leucine aminopeptidase with significant increase in its activity. Similarly, under saline conditions, MBC and soil respiration were significantly higher compared with normal soil. Extracellular enzyme activities were also significantly increased under salinity stress. In contrast, when combined stresses of drought and salinity were applied, cumulative C-CO2 emissions were significantly decreased (968+91 mg C kg-1 soil) as evident by decreased β-glucosidase activity, involved in C cycling. In contrast, chitinase activity increased under combined abiotic stresses, confirming the availability of chitin from microbial dead biomass degradation. It was concluded that microbes adopted drought and salinity stresses when applied individually but combined salinity with drought stress limited microbial biomass and microbial activities in soil. [ABSTRACT FROM AUTHOR]

Root mucilage modulates soil-plant-water dynamics, but its interactions with microbial community functioning remain poorly understood. The aims of this study were to estimate (I) the impacts of mucilage and soil water content on the microbial community composition and (II) the mucilage consumption by individual microbial groups. C4 root mucilage from maize (at 40 and 200 μg C per gram dry soil, corresponding to 10 and 50% of soil microbial biomass, respectively) was added in single pulses to a C3 soil at two moisture levels: optimum (80% of water-holding capacity (WHC)) and drought (30% of WHC). After 15 days of incubation, the microbial community composition was studied by phospholipid fatty acids (PLFA) analysis and incorporation of mucilage-derived C into individual microbial groups was determined by compound-specific isotope analysis. Microbial community composition remained largely unaffected by mucilage addition but was affected by moisture. Whereas an increase in water content reduced mucilage C recovery in PLFA for the low-dose mucilage amendment from 19 to 9%, it had no effect under the high-dose amendment (11-12%). This suggests that the role of mucilage for microbial functioning is especially pronounced under drought conditions. The fungal PLFA 18:2ω6,9 was present only under drought conditions, and fungi profited in their mucilage C utilisation from the lower competitiveness of many bacterial groups under drought. In this study, Gram-negatives (G−, characterised by PLFA 18:1ω9c, 18:1ω7c, 16:1ω7c and cy17:0) showed the highest mucilage-derived C in PLFA, especially at the high-dose amendment, suggesting them to be the major decomposers of mucilage, especially when the availability of this C source is high. Gram-positives (G+) included different sub-groups with distinct responses to moisture: G+ 1 (a15:0) were only competitive for mucilage C under drought, whereas G+ 3 (i17:0) were only able to utilise mucilage-derived C under optimal moisture conditions. During the 15-day incubation, they built up more than 40% of their membranes from mucilage-derived C, suggesting that in the case of high availability, mucilage can act as an important C source for this microbial group. However, under drought, G− 1 and fungi were incorporating the most mucilage C into their membranes (approx. 20% of PLFA-C). The observation that, for some groups, the high-dose mucilage amendments under drought led to higher C incorporation into PLFA than under optimum moisture suggests that mucilage can compensate drought effects for particular microbial groups. Thus, mucilage may not only act as a C source for microorganisms but may also mitigate drought effects for specific rhizosphere microbial groups. [ABSTRACT FROM AUTHOR]

Durability and suitability of concrete aggregates are influenced by mineralogical composition. This paper therefore discuses the mineralogical composition of Jhelum river aggregates and identifies the deleterious components responsible of ASR expansion, when used in normal weight concrete. Accelerated Mortar Bar Test (ASTM C-1260) and petrographic analysis were performed to determine the durability aspects of river aggregate. Aggregate Suitability was assessed by aggregate quality tests i.e. specific gravity & absorption, Loss Angeles abrasion, sulfate soundness, shape test, fineness modulus and sand equivalent. On obtaining satisfactory results of coarse aggregate tests, concrete mix designs for class-A, class-B, class-C and class-D were devised by absolute volume method (ACI- 211.1). Projected UCS (Unconfined Compressive Strength) considered 4000Psi for A-type, 3000Psi for B-type, 2000Psi for C-type and 1500Psi for D- type concrete at the at 28days. Results of 24 casted cylinders show that achieved average UCS at the age of 28 days is, 4921 Psi, 3773 Psi, 2780 Psi and 2432Psi for A, B, C and D-type concrete respectively. Jhelum River Aggregate is found mechanically fit and suitable for normal weight concrete. There are about 40% samples which deviate from the suitability standard of Accelerated Mortar Bar Test. Mineralogical studies of Jhelum river aggregate revealed that most of the aggregate components (Sandstone, Quartz Arenite) are suitable for construction but some of these are highly susceptible to alkali silica reaction due to the presence of highly strained quartz. The studied river aggregate is economical while used with slag cement and additives. [ABSTRACT FROM AUTHOR]

Despite the presence of a huge amount of potassium (K+) in the soil, most of the soils are deficient in plant available K+. A large amount of the K+ is fixed by clay minerals present in such soils and cannot be taken up by plants to achieve optimum plant growth. In such type of soils, large amount of K+ fertilizers are required for optimum plant growth, as plants do not respond enough to a normally recommended K+ fertilization. Vermiculite clay minerals can fix an enormous amount of applied K+, which becomes slowly available to the plants. The K+ dynamics in such soils are valuable to recommend K+ fertilizer requirements for sustainable nutrient management. We analyzed the K+ dynamics of three alluvial soils, i.e Kleinlinden, Giessen and Trebur, collected from Germany and found that the soils with vermiculite and smectite clay minerals have more K+- fixing ability than soils dominated by illite clay minerals. However, as the K+ concentration decreased in the soil solution, smectite-dominant soils may easily release fixed K+ due to lower particle-charge, whereas vermiculite and illite dominant soils may not release fixed K+ easily. Moreover, ammonium exchangeable K+, non-exchangeable K+, total K+ and K+-fixing capacity of these soils are directly proportional to the soil clay contents. While recommending K+ fertilizers clay contents and the type of clay minerals is not considered and recommended K+ fertilizers sometimes do not response plant growth enhancement. Therefore potassium fertilizer should be recommended by taking into consideration the type and amount of clay minerals present in the soil. [ABSTRACT FROM AUTHOR]

Background: Sequestering carbon dioxide (CO 2 ) in agricultural soils promises climate change mitigation as well as sustainable ecosystem services. In order to stabilize crop residues as soil carbon (C), addition of mineral nutrients in excess to crop needs is suggested as an inevitable practice. However, the effect of two macronutrients i.e ., nitrogen (N) & phosphorus (P), on C cycling has been found contradictory. Mineral N usually decreases whereas mineral P increases the soil organic C (SOC) mineralization and microbial biomass. How the addition of these macronutrients in inorganic form to an organic-matter poor soil affect C cycling remains to be investigated., Methods: To reconcile this contradiction, we tested the effect of mineral N (120 kg N ha -1 ) and/or P (60 kg N ha -1 ) in presence or absence of maize litter (1 g C kg -1 soil) on C cycling in an organic-matter poor soil (0.87% SOC) in a laboratory incubation. Soil respiration was measured periodically during the incubation whereas various soil variables were measured at the end of the incubation., Results: Contrary to literature, P addition stimulated soil C mineralization very briefly at start of incubation period and released similar total cumulative CO 2 -C as in control soil. We attributed this to low organic C content of the soil as P addition could desorb very low amounts of labile C for microbial use. Adding N with litter built up the largest microbial biomass (144% higher) without inducing any further increase in CO 2 -C release compared to litter only addition. However, adding P with litter did not induce any increase in microbial biomass. Co-application of inorganic N and P significantly increased C mineralization in presence (19% with respect to only litter amended) as well as absence (41% with respect to control soil) of litter. Overall, our study indicates that the combined application of inorganic N and P stabilizes added organic matter while depletes the already unamended soil., Competing Interests: Tanvir Shahzad and Sabir Hussain are Academic Editors for PeerJ., (© 2024 Anwar et al.)