Soil Nutrient Research Articles (Page 1)

Maize is potentially important for human nutrition and contributes to strengthening food security, parallel to the cultivation of rice. Due to the nutritional value, dietary energy source and the emerging limitations of rice farming in the reduced water supply scenario in India during winter, the growing trend of adopting maize, especially in the rabi season under judicious nutrient management practices, is in high demand. However, fewer findings are available on enhancing the rabi maize productivity with balanced nutrient management in the coastal tracts of West Bengal. Based on the above facts, a field experiment was conducted to study the effect of different doses of phosphorous in combination with Vesicular Arbuscular Mycorrhiza (VAM) and Phosphate-Solubilising Bacteria (PSB) for enhancing growth and yield of maize in rabi season of 2024-25 comprising ten treatments, conjoining biofertilizers either solely without any chemical phosphorous or with different levels of chemical phosphorous separately that can boost the productivity of rabi maize. The P2O5 application at 60 kg/ha, combined with VAM inoculation at 20 g/kg seed exhibited the highest grain yield (5.91 t/ha) and stover yield (8.31 t/ha), as well as all growth and yield parameters, indicating the most suitable synergistic impacts between the bioinoculant and inorganic phosphorus. The aforesaid treatment was closely followed by applying P2O5 @ 40 kg/ha + VAM inoculation @ 20 g/kg, with the grain yield of 5.53 t/ha, and it remained significantly inferior in enhancing the grain yield of maize. The combined impact of 60 kg phosphorus + 20 g VAM/kg seed reflected better plant growth that eventually increased the grain yield of rabi maize, which can be recommended for the coastal areas of West Bengal.

The agricultural development of saline alkali land has always been an important direction for improving land use efficiency and food production. The study aims to explore the effects of biomass organic fertilizer and reducing the use of chemical fertilizers on watermelons in saline alkali land, providing a scientific basis for the sustainable development of saline alkali agriculture. The study selects a mixed application of biomass organic fertilizer and chemical fertilizer with different proportions, and compares the growth, yield, and quality of watermelon in saline alkali soil. The research results indicated that the biomass organic fertilizer improved the growth rate and yield of watermelon in saline alkali soil. Compared with conventional fertilization treatment, the combination of biomass organic fertilizer and weight loss significantly increased soil organic matter content and promoted watermelon growth. In addition, watermelon treated with biomass organic fertilizer also performed better in terms of quality, including better fruit size, soluble solid content, and vitamin C content than conventional fertilizer treatment. The study also found that applying organic biomass fertilizer and weight loss in saline alkali land can increase the yield and quality of watermelons, and have a significant improvement effect on soil nutrients. This fertilization method could effectively increase the soil organic matter content and provide a more suitable environment for the growth of watermelons. The above results indicate that the proposed combination has significant advantages in watermelon cultivation in saline alkali land, and is significant for the sustainable development of saline alkali agriculture.

Molecular mechanisms modulating beneficial plant root-microbe interactions: What's common?

Fertilization managements mitigate microbial carbon and nitrogen limitations while preserving soil organic carbon in croplands compared to grasslands: A meta-analysis.

Abstract It is essential to reduce pesticide and tillage use in agricultural systems, but better alternatives for controlling perennial weeds are needed. The horizontal and vertical root cutters can fragment the roots and rhizomes of perennial weeds with minimal disturbance to the soil and vegetation cover. However, there is a lack of studies on how the root cutters affect multiple perennial weed species, and their effect on soil and nutrient losses. To fill this gap, three multi-year experiments in plowed systems were conducted in Norway and Sweden to study whether the roots cutters can control multiple perennial weed species as effectively as more intensive tillage methods (Experiments 1-2), without increasing soil and nutrient losses (Experiment 3). Overall, the more intensive tillage methods tested (rotary tiller, disc harrow, stubble harrow) did not provide significantly better perennial weed control than the horizontal root cutter. In Experiment 1, the horizontal root cutter reduced Sonchus arvensis and Elymus repens shoot biomass by 52% and 80%, respectively, compared to an untreated control. In Experiment 2, the horizontal root cutter reduced Cirsium arvense shoot numbers by 71% compared to the untreated control but failed to reduce E. repens . Horizontal root cutter treatment depth (7 vs. 15 cm) did not affect control efficacy. The horizontal root cutter treatment did not increase soil, water or nutrient losses compared to the untreated control, and resulted in 60% less soil and 52% less phosphorous losses than disc harrowing. Treatments with the vertical root cutter had 40% less E. repens and 22% less S. arvensis shoot biomass than treatments without the vertical root cutter. This manuscript is the first to show the true potential of the root cutters in plowed systems in northern Europe and their ability to control of multiple perennial weed species with low risk of soil and nutrient losses.

Abstract Background and Aims Transferring pure forests to more resilient and productive mixtures is commonly recommended. However, how introduced species with different identities impact the soil microbiome and nutrient cycling is not well understood. Methods We investigated the changes of soil physicochemical properties and microbial community following admixing the evergreen deep-rooting camphor ( Cinnamomum camphora ) and the deciduous N 2 -fixer alder ( Alnus cremastogyne ) into a pure cypress ( Cupressus funebris ) forest. Results Admixing significantly enhanced soil water, total nitrogen (N) and total phosphorus (P) contents. Soil pH, available P levels as well as alkaline phosphatase (ALP) activity were significantly increased in the vicinity of alder, while the presence of camphor improved available N and potassium (K) contents. Compared to the cypress monoculture, the two mixtures exhibited higher soil microbial diversity and a greater abundance of the dominant phyla Proteobacteria and Acidobacteria. Which contributed to improved soil nutritional status through enhanced N fixation, inorganic P solubilization and organic matter decomposition. In addition, genes related to methanogenesis, nitrification, denitrification and methane oxidation were markedly decreased in the two mixed stands. Our study showed that introducing alder or camphor improved N cycling without causing higher N loss. Moreover, compared to the evergreen camphor, the deciduous N 2 -fixer alder favored bacterial communities stimulating organic P mineralization, nitrite and nitric oxide reduction. Conclusion Our study reveals the significant effects of admixing on the soil bacterial community and its potential effects on nutrient cycling, highlights the importance of introduced species identities, and provides instructions for designing and managing mixed-species stands.

Soil nutrient detection in wetlands is critical for rapidly and effectively managing these ecosystems. Our objective was to provide a methodological framework for identifying optimal data processing methods and machine learning model for predicting soil organic carbon (SOC) and total nitrogen (TN) content using Vis–NIR spectroscopy, under the confounding influence of varying soil moisture. Soil samples (474) were collected from the Shaanxi Yellow River Wetland Provincial Nature Reserve with five moisture levels (0, 5, 10, 20, and 30%). Using a Vis–NIR spectroscopy system (ASD FS4 spectrometer), soil organic carbon (SOC) and total nitrogen (TN) were detected within the 350–2500 nm spectral range. Machine learning models were established using the Random Forest model (RF), eXtreme Gradient Boosting (XGBoost), and Partial Least Squares Regression (PLSR). The results indicated: (1) spectral reflectance values increased as soil moisture content decreased, with the 0% moisture model being consistently more accurate; (2) models for SOC and TN on first-derivative spectra had higher accuracy; and (3) the RF exhibited higher inversion accuracy and stability (R2 = 0.30–0.69). (4) The SHAP analysis confirmed 1865 nm and 1419 nm as the most contributory bands for SOC and TN prediction respectively, validating the RF model’s spectral interpretation capability.

Soil fertility in sub-Saharan Africa is increasingly affected by climatic stressors that accelerate nutrient loss and threaten farming sustainability. In Adamawa State, Nigeria, where many people depend on agriculture, rising temperatures, inconsistent rainfall, and frequent floods make soil degradation worse. This study assesses the vulnerability of soil nutrients to climate change impacts by using soil sampling, lab analysis, and long-term weather data. Composite soil samples were taken at two depths (0–30 cm and 30–60 cm). Rainfall, temperature, and relative humidity records from 2001 to 2021 were analyzed along with rainfall erosivity data and recorded flood events. The study adopted Pearson correlation and paired t-tests for its statistical analyses, the findings revealed significant negative correlations between rainfall and phosphorus (r = –0.68), potassium (r = –0.54), and organic matter (r = –0.63), particularly in surface soils. Flood events significantly reduced phosphorus (p < 0.001), potassium (p = 0.003), and microbial biomass carbon (p = 0.004). Rainfall erosivity exhibited marked interannual variability, peaking in 2008, 2012, 2014, 2018, 2019, and 2021. The study concludes that surface soils in Adamawa are highly vulnerable to climatic stressors and recommends the adoption of climate-smart soil management and erosion control strategies to enhance resilience and sustain agricultural productivity.

Long-term fertilization affects soil nutrient levels and aggregate stability, eventually altering crop yield. However, their responses to organic fertilizer application and straw returning are still unclear, particularly as the contributions of soil nutrient levels and aggregate stability on crop yields remain poorly quantified. Therefore, topsoil samples (0–20 cm) were collected from six fertilization treatments in a long-term (13-year) Shajiang black soil field experiment with no fertilization (CK), chemical fertilization (NPK), 50% NPK plus pig manure (50%NPKP), 50% NPK plus cattle manure (50%NPKC), 70% NPK plus pig manure with straw return (70%NPKPS), and 70% NPK plus cattle manure with straw return (70%NPKCS). We examined the characteristics of crop yield, soil nutrient levels, and soil aggregate stability parameters, including under different long-term fertilization treatments. The results show that long-term fertilization significantly influenced the distribution of soil nutrients and soil aggregates in Shajiang black soil. Compared to CK, organic fertilizers and straw returning significantly increased the soil organic matter (SOM), total nitrogen (TN), and total phosphorus (TP) contents but decreased soil pH, respectively, indicating the best strategies for improving soil fertility. Compared to the CK and NPK treatments, long-term organic fertilization and straw returning significantly increased the mean weight diameter (MWD) and geometric mean diameter (GMD) values and significantly decreased the fractal dimension (Dm) and mean weight-specific surface area (MWSSA) values, with the 70%NPKCS treatment showing the most pronounced effect of improving aggregate stability. A redundancy analysis revealed that SOM and TN exert significant effects on aggregate stability. Furthermore, a stepwise regression analysis showed that SOM and TN were positive factors affecting the yields of wheat and maize, while MWD and pH were negative factors affecting wheat yield, demonstrating that high crop yields are derived from soils with limited stability and high fertility. Thus, our findings indicate that the integrated application of cattle manure with straw returning was the most effective strategy to promote soil nutrient accumulation, improve aggregate stability, and enhance crop yield, albeit with the potential risk of soil acidification, which requires management in the Shajiang black soil (Vertisol) region of Northern China.

Soil health is a fundamental pillar of sustainable agriculture, environmental resilience, and global food security. In recent decades, agronomic-engineered technologies such as conservation agriculture, precision nutrient management, organic amendments, biochar, microbial inoculants, cover cropping, digital diagnostics, and integrated soil–water management have been developed to restore fertility, enhance nutrient cycling, and improve climate resilience. Yet, successful adoption of these technologies depends not only on their availability but also on farmers’ knowledge, skills, and confidence, which are primarily fostered through educational and training programs. This review evaluates extension-based interventions, including farmer field schools, on-farm demonstrations, ICT platforms, workshops, and blended learning approaches, that serve as the interface between scientific innovations and on-farm practices. The synthesis highlights that program effectiveness hinges on contextualization, intensity, follow-up support, and inclusivity of women, youth, and marginalized groups. Outcomes extend from immediate learning gains to medium-term adoption, measurable improvements in soil organic carbon, nutrient balance, and microbial activity, and longer-term productivity, livelihood, and environmental benefits. Barriers such as institutional limitations, financial constraints, and knowledge dilution hinder scaling, while enablers include public–private partnerships, farmer cooperatives, digital platforms, and incentive schemes. Scaling strategies like hub-and-spoke models and participatory approaches are shown to enhance outreach and sustainability. The review concludes that context-sensitive, participatory, and systematically evaluated training programs are essential to transform technological potential into tangible soil health and socio-economic gains.

Salinity is a major abiotic stress limiting maize (Zea mays L.) productivity, particularly in arid and semi-arid regions. This study evaluated the efficacy of gibberellic acid (GA3) and biochar in mitigating salinity-induced growth inhibition in maize. The objective was to assess the synergistic effects of GA3 and biochar on germination, growth parameters, and photosynthetic capacity under saline conditions, and to identify practical strategies for improving crop performance in salt-affected soils. A pot experiment was conducted at the Islamia University of Bahawalpur, Pakistan, using a Completely Randomized Design (CRD) with four replications per treatment, resulting in 32 pots. The study included eight treatment combinations: control, GA3, biochar, and GA3 + biochar under two salinity levels (2.41 and 6 dS·m⁻1). Key parameters analyzed included germination rate, shoot and root length, shoot and root biomass, protein content, and chlorophyll content. Under high salinity (6 dS·m⁻1), the combined application of GA3 and biochar improved germination to 73.5% ± 0.5 compared to 66.5% ± 0.5 in the control. Shoot and root lengths increased to 16.28 ± 0.15cm and 5.90 ± 0.12cm, respectively, compared to 10.73 ± 0.45cm and 5.16 ± 0.05cm in the control. Chlorophyll content also increased, indicating improved photosynthetic performance. The findings demonstrate that GA3 and biochar together can alleviate the adverse effects of salinity stress by promoting early growth and physiological performance in maize. Incorporating these amendments into agronomic practices may provide a sustainable strategy to enhance maize productivity in saline soils. Future studies should evaluate their long-term effects on soil health, nutrient dynamics, and crop yield under field conditions.

In Eritrea, efforts are being made to tackle the widespread land degradation and promote natural resources and the agricultural sector. However, these efforts lack digital resources assessment, mapping, planning and monitoring. Thus, we developed soil organic carbon (SOC) predictor models for the Western Lowlands of the country, employing 6 machine learning models with different input variables (36, 27, 15, and 08) obtained following these variables selection strategies: (1) all proposed SOC predictor variables; (2) very high multicollinearity (≥0.900 **) reduction; (3) high multicollinearity (≥0.700 **) reduction; (4) the Boruta feature selection algorithm. The results revealed that SOC levels were generally low (mean = 0.43%). Grazing lands, rainfed croplands, and irrigated farmlands all exhibited similarly low SOC values, attributed to unsustainable land management practices that deplete soil nutrients. In contrast, natural forestlands exhibited significantly higher SOC concentrations, highlighting their potential for soil carbon sequestration. Among the tested models, the XGBoost algorithm using 27 covariates achieved the highest predictive performance (RMSE = 0.118, R2 = 0.758, RPD = 2.252), whereas the multiple linear regression (MLR) model with 8 variables yielded the lowest performance (RMSE = 0.141, R2 = 0.742, RPD = 1.883). Compared to the Boruta-based feature selection, the MLR, PLS, XGBoost, Cubist, and GB models showed performance improvements of 10.41%, 10.06%, 6.72%, 6.50%, and 3.15%, respectively. Rainfall emerged as the most influential predictor of SOC spatial variability in the study area. Other important predictors included temperature, soil taxonomy, SWIR2 and NIR bands from Landsat 8 imagery, as well as sand and clay contents. We conclude that reducing very high multicollinearity is essential for improving model performance across all tested algorithms, while reducing moderate multicollinearity is not consistently necessary. The developed SOC prediction models demonstrate robust predictive capabilities and can serve as effective tools for supporting soil fertility management, land restoration planning, and climate change mitigation strategies in the Western Lowlands of Eritrea.

The steel industry has grown rapidly, leading to the production of large quantities of steel slag, a by-product from processes like basic oxygen, electric arc, and ladle furnaces. Once seen as an industrial waste, steel slag is now valued in agriculture as a soil enhancer and nutrient source. This review aims to summarise key findings on how steel slag affects soil chemistry, nutrient dynamics, microbial interactions, and crop performance, while also addressing safety and practical considerations for its use in agriculture. This review highlights the benefits of using steel slag in sustainable farming, focusing on its nutrient content, environmental safety, and influence on crop productivity. It is rich in essential plant nutrients such as calcium, silicon, magnesium, and phosphorus, along with micronutrients like iron and manganese. Its alkaline nature helps to reduce soil acidity, improve nutrient availability, and support microbial activity in the soil. Steel slag is a by-product produced during steel manufacturing and is mainly generated from three types of furnaces: basic oxygen furnaces (BOF), electric arc furnaces (EAF), and induction furnaces (IF). Steel slag also has the ability to reduce the mobility of harmful metals like cadmium, arsenic, and lead, lowering the risk of heavy metal contamination in crops. Its application improves crop growth, enhances stress tolerance, and boosts yield. Steel slag with biochar in paddy fields raised soil pH by 14.2% and salinity by 98% compared to untreated soil. Field studies from Bangladesh, China, Japan, Indonesia, and Korea have shown that slag fertiliser can reduce methane emissions from rice fields by 0.6% to 56% depending on factors like soil type, slag composition, and application rate. Moreover, it helps to reduce methane and nitrous oxide emissions in flooded rice fields by altering soil microbial dynamics and redox conditions. When combined with materials like biochar, slag enhances carbon retention and microbial health, supporting long-term soil fertility. This review compiles recent research on various types of slag used in farming, emphasising their role in improving soil properties, limiting toxic metal uptake, and supporting sustainable crop production. It also addresses safety and regulatory considerations for practical use in agriculture. Research has shown that slag use can increase crop yields, improve plants’ resistance to stress and diseases, and make farming more sustainable. With proper management, steel slag can be a low-cost, eco-friendly option to improve soil quality and support sustainable agriculture.

Elephant grass is native to tropical Africa and the sub-Saharan region and has been introduced as a valuable and popular forage crop in many tropical and subtropical countries. Poultry manure is a valuable source of organic matter and nutrients that enhance soil fertility and promote the growth of crops. This study investigated the effects of varying rates of poultry manure on the morphological characteristics of elephant grass (Pennisetum purpureum) at the Department of Crop Science Teaching and Research Farm, University of Nigeria, Nsukka. The experiment employed a Completely Randomised Design (CRD) with five treatments: 0 (control), 5, 10, 15, and 20 tons of poultry manure per hectare, replicated five times. Morphological parameters, including stem height, stem girth, leaf length, and number of shoots, were measured weekly for eight weeks after planting. The data obtained were analysed using analysis of variance (ANOVA). Results demonstrated that poultry manure significantly (P<0.05) influenced elephant grass growth from weeks 2 to 8, while only stem height was significant in week 1. Although the application rates of 10 and 15 t/ha did not differ significantly (P>0.05), the 15 tons/ha application rate consistently produced the highest mean values across all morphological parameters, closely followed by the 10 tons/ha rate. Notably, the control treatment (0 tons/ha) exhibited the lowest growth responses, highlighting the critical role of organic amendments in soil fertility and plant development. The 20 tons/ha rate underperformed compared to moderate rates, suggesting potential nutrient toxicity or soil structure complications at higher application levels. The study concluded that moderate poultry manure application rates (10-15 tons/ha) optimise elephant grass establishment by providing an ideal balance of nutrients, improving soil moisture retention, and enhancing microbial activity. Ultimately, the research recommends a 10 tons/ha application rate for farmers, balancing cost-effectiveness, environmental considerations, and forage production efficiency.

Soil erosion and deposition are critical processes affecting soil quality and crop productivity, particularly in hilly agricultural regions. Topsoil removal reduces soil fertility and degrades root development, threatening sustainable crop production. This study aimed to evaluate how different degrees of topsoil erosion and deposition, combined with different fertilization strategies,influence soil quality and peanut (Arachis hypogaea L.) root morphology. We sought to determine effective fertilization measures for restoring soil functionality and improving root growth under erosion stress. A controlled pot experiment simulated five topsoil redistribution scenarios: moderate (10 cm) and severe (20 cm) erosion and deposition, and a no-change control. Each scenario was combined with four fertilization treatments: no fertilizer, inorganic fertilizer, organic fertilizer, and combined organic-inorganic fertilizer. Soil chemical properties, soil quality index (SQI), and peanut root morphology were assessed. Topsoil erosion reduced soil organic matter, nitrogen, and phosphorus contents, with 20 cm erosion decreasing root diameter at flowering by 21.8% under inorganic fertilization and 19.3% under combined fertilization compared with the control. Erosion consistently resulted in reduced plant height, root diameter, root length, root surface area, and root volume. In contrast, deposition improved soil nutrient availability, enhancing root growth. Root length increased by 75.5% and root surface area by up to 116.7% under 20 cm deposition with combined fertilization, relative to the control. Fertilization mitigated erosion effects, with the combined organic–inorganic treatment achieving the highest SQI and best root performance. The maximum SQI value (0.417) was observed under 20 cm deposition, and combined fertilization consistently outperformed inorganic or organic fertilization alone. Organic fertilizer alone maintained more stable root morphology under erosion conditions. Topsoil redistribution profoundly alters soil quality and root morphology in peanut production. Appropriate fertilization, particularly combined organic–inorganic application, is essential for restoring soil functionality and sustaining crop productivity in erosion-affected areas.

Abstract. High-throughput phenotyping monitoring has become increasingly important in modern agriculture, as it can collect plant images to extract and analyse phenotype data related to growth and yield, thereby reducing crop monitoring costs. Aboveground biomass (AGB) is a key indicator for evaluating plant health, growth, and productivity, and reflects the impact of environmental factors (such as water, soil nutrients, and temperature) on plants. However, traditional methods for measuring AGB are often labor-intensive, costly, and limited in spatial coverage. Unmanned aerial vehicles (UAVs)-based remote sensing offer new solutions, enabling large-scale, high-resolution data collection in agricultural fields. Therefore, this study evaluates the use of Vegetation indices (VIs) and Texture features (TFs), as well as their combinations, derived from UAV multispectral imagery to estimate peanut AGB across different growth stages. Specifically, nine VIs and eight TFs with different parameter settings were first derived from RGB and four single-band UAV images. Based on random forest (RF) regression, the study explored the impact of different parameter combinations on the performance of AGB models and analysed the potential of combining VIs and TFs to improve AGB estimation. The results show that TFs effectively complement VIs, significantly enhancing peanut AGB estimation performance. The optimal window size was 7×7, with a direction of 90° and a grey level of 16. The combined VIs and TFs yield a regression with R² and RMSE of 0.929 and 0.032, respectively. These findings suggest that the strategy of extracting image textures and combining features significantly improves the accuracy of AGB estimation, providing a more precise method for monitoring AGB.

Most traits of assimilative branches (ABs) present large spatial and interspecific differences; however, it is still unclear how small-scale soil heterogeneity influences nutrient traits in ABs under the same climatic conditions. The AB samples of Ephedra przewalskii (EP; small-sized), Calligonum mongolicum (CM; medium-sized), and Haloxylon persicum (HP; large-sized), as well as soil samples, were collected at three sites (north, middle, and south; within 65 km) in the southeastern Gurbantunggut Desert, China. The interspecific and inter-site differences in C:N:P:K stoichiometry and the relationships with soil properties were discussed. From north to south, soil nutrients and biocrust development improved, whereas coarse sand proportion decreased. Species and site markedly influenced ABs’ stoichiometry, with a significant interaction. At the species level, each stoichiometric trait differed among species. CM exhibited the lowest C:P and N:P, whereas HP had the highest N:P. At the site level, N:P and C:P of EP and CM increased from north to south, whereas HP changed unclearly. CM and HP had higher N–P scaling exponents, EP and CM exhibited a higher K allocation rate, resulting in the co-limitation of N and P for all species. The overall stoichiometric homeostasis ranked as follows: HP > CM > EP. The three shrubs were dispersed among each other in an ordination diagram based on nutrient metrics, with different distribution patterns. The nutrient traits in the ABs of EP and CM, rather than HP, were markedly correlated with most soil factors. Local-scale soil variation indeed influenced the nutrient strategies of desert shrubs; plant size might be another important factor.

Aims Plant ecological stoichiometry focuses on the elemental content (such as carbon (C), nitrogen (N), and phosphorus (P)) in plant organs and its relationship with environmental factors and ecosystem functions. Alien invasive species ensure their rapid and efficient propagation by regulating their nutrient distribution, and they also influence soil physical and chemical properties by modifying the nutrient cycle and releasing allelochemicals, thus forming an environment conducive to their growth, reproduction, and diffusion. However, evidence on the ecological stoichiometry characteristics of the invasive plant Solanum rostratum and its invaded soils across different habitats in China, particularly the species’ nutrient utilization strategies in varying environments, is lacking. Methods This study investigated S. rostratum in Xinjiang Province of China and analyzed the organ allocation of C, N, and P and stoichiometric characteristics across four distinct habitats (irrigation ditches, riparian zones, desert steppes, farmlands) through field surveys and controlled laboratory experiments. In addition, a conceptual framework elucidating S. rostratum ’s invasion mechanisms, nutrient-use adaptations, and plant-soil feedback was established. Results The results demonstrated that S. rostratum exhibits significant stoichiometric adaptation strategies in different habitats, thus providing a scientific foundation for understanding its invasion mechanisms and formulating effective control measures. The results indicated that significant differences in C, N, and P content occurred among the organs of S. rostratum , with a peak in reproductive tissues (flowers, fruits). Conclusion This priority allocation to reproduction underscores an evolved strategy for optimizing fitness. Moreover, with changes in the invasion degree of S. rostratum , the soil nutrient cycle changed, with obvious differences in the responses of different habitats. This indicates that S. rostratum invasion not only affects its own growth but also affects the nutrient cycle of the whole ecosystem by changing the soil nutrient status. In addition, habitat type had a significant impact on the element accumulation of S. rostratum , and the quantitative relationship between plant and soil elements showed obvious habitat specificity. This phenomenon reflects the driving roles of environmental stress and resource availability on plant growth. S. rostratum adjusts its element absorption and distribution strategies under the environmental and resource conditions of different habitats as an adaptation to environmental changes. Therefore, S. rostratum adapts to heterogeneous environment or heterogeneous condition. Accordingly, differentiated control strategies tailored to its invasion characteristics in distinct habitats should be formulated to enhance its control efficiency.

To explore the feasibility of substituting sawdust with tobacco stalks for cultivating Stropharia rugosoannulata and its impact on soil properties, this study designed cultivation formulas with varying tobacco stalk ratios (0-50%) and analyzed mycelial growth rates, fruiting body agronomic traits, and changes in soil nutrients and enzyme activities. Results showed that the mycelial growth rate first increased and then decreased with a higher tobacco stalk ratio when tobacco stalk ratio was below 50%. T4 (30% tobacco stalks) was optimal with the highest rate (1.69 cm/d), as its tobacco stalk particle size improved mycelium-substrate contact and aeration. D3 (10% tobacco stalks + 90% corn stalks) had the best stipe/cap diameter, individual weight and available K (543.29 mg/kg), while D4 (20% tobacco stalks + 80% corn stalks) showed the highest alkali-hydrolyzed N (118.77 mg/kg) and balanced performance. D6 (100% corn stalks) had the highest available phosphorus content (6.38 mg/kg). Soil enzyme activity analysis indicated that invertase activity peaked in D6 (153.12 mg/g d⁻¹), whereas urease activity was highest in D5 (1.75 μg/g d⁻¹). Correlation analysis showed that the tobacco stalk ratio was extremely positively correlated with the mushroom shape index (r = 0.729**), and urease activity was significantly negatively correlated with fruiting body agronomic traits. In conclusion, T4 promoted mycelial growth, while D3 and D4 aligned soil nutrient improvement with the growth requirements of fruiting bodies, and D4 emerged as the most well-rounded treatment due to its balanced carbon-nitrogen release and favorable fruiting body phenotypic traits. Bangladesh J. Bot. 54(3): 831-840, 2025 (September) Special

Declining soil fertility and ongoing land degradation from traditional shifting cultivation pose significant challenges to sustainable agriculture in the upland regions of Northeast India. This study provides a comparative analysis of soil nutrient dynamics and crop productivity under Jhum cultivation and integrated farming systems in three villages of Mamit District, Mizoram. Soil samples were collected during pre-monsoon and post-monsoon periods and analyzed for pH, organic carbon, nitrogen, phosphorus, and potassium. Statistical analyses, including analysis of variance and principal component analysis, were employed to assess differences in soil quality. A Soil Quality Index was also developed to enable comprehensive system comparisons. Results indicate that integrated farming system (IFS)-soil quality managed plots consistently maintained higher values compared to Jhum plots, as well as significantly higher Soil Quality Index scores, especially in the post-monsoon period. In contrast, Jhum fields exhibited pronounced nutrient depletion and reduced soil quality after cropping cycles. Principal component analysis further distinguished the two systems, linking the IFS to greater soil fertility stability. Crop yield data reinforced these findings, with notably higher yields of paddy, chili, and pumpkin under IFS. This study highlights the ecological and agricultural advantages of adopting integrated farming over traditional Jhum practices. It recommends expanding IFS adoption through targeted capacity building, infrastructural support, and participatory extension services. These insights provide an essential foundation for formulating sustainable land management policies aimed at improving food security and environmental resilience in fragile hill ecosystems.