Tahsina Sharmin Hoque

This study evaluated the effects of applying fecal sludge-based co-compost (CC) integrated with chemical fertilizers on soil nutrient status, organic carbon (OC) storage, and economic returns in paddy soils. Ten integrated nutrient management (INM) treatments were tested, i.e., BRRI recommended dose of fertilizer (RDF), CC 5.0 t ha⁻¹, RDF + CC 2.0 t ha⁻¹, RDF + CC 1.5 t ha⁻¹, RDF + CC 1.0 t ha⁻¹, RDF + CC 0.5 t ha⁻¹, 75% RDF + CC 2.0 t ha⁻¹, 75% RDF + CC 1.5 t ha⁻¹, 75% RDF + CC 1.0 t ha⁻¹, and 75% RDF + CC 0.5 t ha⁻¹. Two rice varieties were cultivated over two consecutive seasons—winter rice (boro) and monsoon rice (aman)—in the experimental field. Soil samples (0–15 cm) were collected before and after the seasons and fractionated into labile particulate organic matter (>53 µm) and stable mineral-associated organic matter (−1 or 1.5 t ha⁻¹ of CC consistently showed the highest OC, total N, and soil C stock, with moderate P, K, and S levels. Sole RDF produced the lowest OC and N. Among fractions, stable OC was the highest in the 75% RDF + 2.0 t ha⁻¹ CC treatment, statistically similar to 75% RDF + 1.5 t ha⁻¹ CC, and the lowest under RDF alone. Economically, sole RDF yielded the highest profit, while full RDF + CC achieved competitive returns. Reduced RDF + CC treatments (75% RDF + 1.5 or 2.0 t ha⁻¹ CC) offered slightly lower returns but improved soil sustainability indicators. Overall, applying 75% RDF + 1.5 t ha⁻¹ CC provided the most cost-effective balance of nutrient enrichment, soil C stock, and profitability. This CC-based INM approach reduces chemical fertilizer dependency, enhances soil health, and promotes sustainable waste management, supporting environmentally resilient rice production.

Soil properties influence land management practices and differ in regions with diverse topography and ecological variations. An experiment was conducted at the Department of Soil Science, Bangladesh Agricultural University, Mymensingh, Bangladesh with 16 soil samples collected at 0-15 cm depth from various hilly locations of three districts of AEZ-29 (Northern and Eastern Hills) covering 12 series to assess their physical, chemical and fertility properties. Most of the soils were sandy loam in texture, strongly acidic to very strongly acidic (pH 4.23-5.46) and non-saline. The cation exchange capacity (CEC) was very low to medium with an average of 7.31 cmolc kg-1 and organic matter (OM) status was medium with mean of 2.62%. The soils had very low to low levels (0.07-0.16%) of total nitrogen (N) and available phosphorus (P) content (1.29-10.9 mg kg-1) but low to medium level (10.33-22.51 mg kg-1) of available sulphur (S). Besides, very low to very high levels of exchangeable potassium (K), calcium (Ca) and magnesium (Mg) with averages of 0.34, 3.10 and 1.64 cmolc kg-1, respectively, were observed. The status of available iron (Fe) and manganese (Mn) in all the soils were very high ranging from 20-108 and 24-217 mg kg-1, respectively. The soils showed medium or low to very high levels of available zinc (Zn), copper (Cu) and boron (B) with averages of 2.64, 0.74 and 0.61 mg kg-1, respectively. The variations in physico-chemical and fertility properties of these soils might be due to variation in parent material, land uses and soil erosion. Among different soil series, Sitakundu showed the maximum values of pH, CEC, OM, total N, exchangeable K, Ca and Mg and available B. Although some of the hill soils seemed to be inherently fertile, proper fertilizer management especially for macronutrients, liming and erosion control practices are crucial for agricultural crop production. SAARC J. Agric., 22(2): 81-98 (2024)

Improving crop productivity and soil fertility through the balanced application of inorganic and organic nutrient sources is a sustainable approach in modern agriculture. Char land soils, widely distributed in riverine Bangla... | Find, read and cite all the research you need on Tech Science Press

In cereal-based farming, there is significant influence of tillage and residue incorporation as sustainable practices, although their role in crop production is still unclear. Two field trials were executed during winter seasons to evaluate the best-performing crop residue and tillage system for the nutrition and yield of rice at the Soil Science Field Laboratory of Bangladesh Agricultural University. In the first trial, residues from soybean, black gram, and rice were incorporated into the soil with 75% recommended fertilizer doses (RFD). The grain yields were 5.97, 6.21, and 6.10 t ha⁻¹, respectively in rice, soybean, and black gram residue-treated plots, which were increased by 77.15, 84.27, and 81.01%, respectively, over the control. In the second trial, the residues from black gram and rice were incorporated with 100% RFD under conventional tillage (CT) and minimum tillage (MT) for two years, where CT with black gram residue plus 100% fertilizer (CT-I₂) exhibited the highest grain yield of 6.69 and 6.88 t ha⁻¹, increasing by 7.61% and 8% over 100% RFD. Both CT and MT performed similarly, and their combination with legume residue strongly influenced crop performance and nutrient uptake. Therefore, incorporating legume residue under minimum tillage can be a sustainable approach for better rice yield and nutritional uptake.

Manganese (Mn) is an essential micronutrient for plants, which influences multiple physiological systems. Determination of the critical limit (CL) of Mn in the soil is necessary for Mn fertilizer application as this limit delineates the deficiency, optimum, and toxicity ranges of Mn. A pot experiment was performed in the winter season with 20 soils collected from three Agro-Ecological Zones (AEZs) of Bangladesh to determine the CL of Mn for soybean (Glycine max L.). Manganese was applied in soil @ 0, 1, 2, and 4 ppm, and the experiment was laid out in a factorial and completely randomized design with three replications. The CL of Mn was determined by the Cate-Nelson graphical and statistical approach and was found 3.60 and 3.55 µg g⁻¹, respectively. Applying 1 µg g⁻¹ Mn in soil significantly enhanced root and shoot weight, as well as seed yield of soybean compared to no Mn application. In field conditions, a significant positive response of soybean yield was found up to the CL of Mn. The findings of the study could help predict possible Mn deficiency in soil and soybean response to Mn fertilizer, which is important in decision-making for efficient fertilizer management practices to ensure the yield potential of soybeans.

Soil organic carbon (OC) is one of the most important soil components regulating soil quality, fertility and agronomic productivity as well as the global carbon (C) cycle. Soil acts as a sink for global C, which can be influenced by the water regime and organic matter (OM) management in field. The aim of this study is to evaluate the effect of the application of different organic amendments on C sequestration in paddy soils under contrasting irrigation regimes. A 4-month pot experiment was conducted under net house conditions and the treatments were composed of two organic amendments: rice straw (RS) and poultry manure (PM); four application rates of amendment: 0 g (control), 2.5 g, 5.0 g and 15.0 g kg⁻¹ soil; and two irrigation regimes: (i) continuous waterlogging condition (CWL) and (ii) alternate wetting and drying (AWD). After the incubation period, soil samples were collected from the pot and isolated into labile (>53 µm) and mineral-associated ( AWD: 35%). This was explained by the induced aerobic condition in between the anerobic condition in AWD and the continuous anaerobic condition in CWL which resulted in a difference in OM decomposition. The mineral-associated OM fraction (−1 soil application under CWL-irrigated paddy soil. The findings indicated the need to pay more attention to the selection of the proper type and rate of organic amendments for higher C sequestration in soil under a specific irrigation system for sustainable agriculture.

Although its mechanism of action, particularly under wetland condition, is not clearly understood, vermicompost, a good source of humus and plant nutrients, has been used as organic manure in many parts of the world in order to increase crop production. Here, an anaerobic incubation study and a field study were conducted to observe the nutrient release pattern from vermicompost and its influence on performance and nutrient uptake in wetland rice. Two contrasting soils, viz. highly weathered terrace soil and very young floodplain soil, were subjected to anaerobic incubation, while the field trial was conducted in the terrace soil with control (no amendments), mineral fertilizer, vermicompost (10 t ha⁻¹) + mineral fertilizer, cow dung (10 t ha⁻¹) + mineral fertilizer, vermicompost (20 t ha⁻¹) + mineral fertilizer and vermicompost (local farmer’s practice) + mineral fertilizer treatments. Results showed that there were significant increases in nitrogen (N) and phosphorous (P) release in floodplain soil but not in terrace soil, suggesting that nutrient release from vermicompost is soil-dependent. The performance of Boro rice in terms of yield and yield attributes improved significantly in the case of the integrated application of vermicompost with mineral fertilizer. Specifically, combined application of mineral nutrients and vermicompost (10 t ha⁻¹) significantly increased grain yield by 25% compared to the control treatment. We believe that this occurred due to an improvement in supply and subsequent uptake of nutrients, especially N and P. Altogether, our results suggest that vermicompost could increase crop performance under field conditions, and, although these effects may not be significant in short-term incubation studies, they may be even larger in floodplain soil.

Acid soil is an obstacle to agricultural development and a concern regarding food and environmental security. Therefore, a study was carried out for two consecutive years to see how lime and organic manure (OM) amendments affect yield and nutrient absorption in the Transplanted (T.) Aman–Mustard–Boro cropping pattern in an acidic terrace soil. With nine treatments and three replications, the experiment was set in a randomized complete block design. The treatments were applied to the first crop, T. Aman, with different dosages of lime (dololime at the rate of 1 and 2 t ha⁻¹), OM (cow dung at 5 t ha⁻¹, poultry manure at 3 t ha⁻¹) and lime–OM combination, and their residual effects were studied in the following mustard and boro rice crops. Results demonstrate that the effect of lime and manure was more pronounced in the case of the second and third crops in the first year and of all crops in the pattern in the second year. In the first year, grain and straw yield of T. Aman as well as the overall system productivity were not influenced significantly by the application of lime and manure, but significant increases were obtained in the second year. As an average of both years, the highest grain yield of 5.2 t ha⁻¹ (12% over control) was recorded for T. Aman, 1.7 t ha⁻¹ (41% over control) for mustard and 5.9 t ha⁻¹ (47% over control, 3.9 t ha⁻¹) for boro rice when dololime was applied in combination with poultry manure. In both years, N, P, K and S uptake were significantly increased compared to the control in all the crops due to the combined application of lime and cow dung or poultry manure. Combined application of lime and manure amendment significantly improved nutrient availability and soil quality. Therefore, applying lime in combination with manure can be practiced to uplift crop productivity in acidic terrace soils.

Globally, the risk of arsenic (As) contamination in soil and rice is well documented across the globe. In Bangladesh, drinking water and rice are two major exposure pathways of As to humans. Therefore, the efficiency of recent technologies to reduce rice As and associated human health risks still need to be deeply investigated. In this direction, a pot experiment was performed to investigate the impact of soil As and agronomic irrigation management on rice (cv. BRRI dhan28) growth, yield, As accumulation, and finally, health risks to humans from consuming rice. Treatment combinations were made with three levels of As (0, 20, and 40 mg kg⁻¹) having two irrigation procedures, including alternate wetting and drying (AWD) and traditional continuous flooding (CF). According to the findings, As pollution in the soil lowered the yield contributing features and rice yield, including panicle length, filled grains per panicle, sterile grains per panicle, 1000-grain weight, grain yield, and straw yield. AWD water management significantly improved the growth performance and productivity of rice. Grain yield was increased by 13% in AWD compared to CF. Rice grain and straw As concentrations were increased to 0.56 mg kg⁻¹ and 15.10 mg kg⁻¹, respectively, in soil with 40 mg kg⁻¹ As and CF water management. AWD treatment significantly reduced grain and straw As contents by 16% and 28%, respectively. Increased grain, straw, and total As uptake was noticed with higher soil As concentrations. The study also found that rising soil As raised non-carcinogenic risks (HQ > 1) and carcinogenic risks (CR > 1.010–4) while AWD lowered health risks compared to CF. Thus, rice farming using AWD irrigation could be a viable and long-term solution for reducing As contamination in rice and associated human health hazards.