DSpace Collection:

Effect of land-use systems on physico-chemical properties of the soil from Vavuniya District

2026-01-01T00:00:00Z

Title: Effect of land-use systems on physico-chemical properties of the soil from Vavuniya District Authors: Murugaspillai, A.; Dilaxsika, S.; Kajeevan, K. ; Shayanthan, A. ; Gnanavelrajah, N.; Kirushnanrajah, V. Abstract: Land degradation is the major threat which leads to decline in soil fertility and other challenges to the Sri Lanka’s dry zone agriculture. The effective land use system is one of the ways to improve and restore soil fertility. In this background, this study aimed to evaluate the effects of six land use systems: permaculture, organic, inorganic, integrated, forest and bare land; physical and chemical soil properties; to identify effective management strategies. Soil samples wre collected from six lands uses in Vavuniya District at two depths (0-15 cm and 15-30 cm) and analyzed for physical parameters (texture, bulk density, porosity, and dry aggregate stability) and chemical characteristics (pH, EC, CEC, available N, P, K, total organic carbon, and soil color). The treatments were arranged in complete randomized design with three replicates and statistical analysis was done by using ANOVA (SAS 9.4) at a 0.05 significance level. The results revealed significant variations across land-use systems and depths. Forest and permaculture soils exhibited significantly improved properties, low bulk density (1.55-1.56 g/cm 3 ), high porosity (> 50%), high CEC (>25 cmol+/kg), and greater total organic carbon (2.46%). In contrast, inorganic and bare lands showed higher compaction (1.64-1.67 g/cm 3 ), reduced porosity, and nutrient depletion. Organic and integrated systems demonstrated moderate improvements, suggesting their potential in rehabilitating degraded soils. These findings emphasize that land-use type profoundly influences physical and chemical properties of the soil. Further studies are needed to document the effect on biological indicators of the soil and the potential of carbon sequestration.

Application of Urea and Muriate of Potash Biochar-Absorbed Forms to Reduce Nutrient Losses

2026-01-01T00:00:00Z

Title: Application of Urea and Muriate of Potash Biochar-Absorbed Forms to Reduce Nutrient Losses Authors: Viyashar, T.; Murugesapillai, A.; Gnanavelrajah, N. Abstract: Though potassium (K) is a cation, it is liable to leaching loss in soils because it is a monovalent one. Considerable leaching of K from applied muriate of potash (MOP) has been reported in soils. Using biochar to absorb MOP may reduce this loss. While urea-intercalated biochar (UIBC) has been studied in Sri Lanka, research on MOP-absorbed biochar is limited. This study aimed to produce potassium-enriched biochar (PEBC) from coir dust and evaluated its potential as a slow-release fertilizer in combination with UIBC, formulated in a previous study. A preliminary research optimized PEBC production under two soaking methods (capillary and direct soaking) and three MOP concentrations (30%, 60%, and 100%) in a two- factor factorial design with three replicates. Statistical analysis (two-way ANOVA, P < 0.05) confirmed that direct soaking, 100% concentration, recorded the highest potassium content 50.87% ± 0.01. A leaching column experiment was conducted using ten treatments: T1 – Control, T2 –Department recommendation, T3-100% UIBC, T4- 75% UIBC, T5- 100% PEBC, T6- 75% PEBC, T7- 100% UIBC + 100% PEBC, T8- 100% UIBC + 75% PEBC, T9- 75% UIBC + 75% PEBC, and T10- 75% UIBC + 100% PEBC, in a completely randomized design (P & lt; 0.05) with four replicates. Over four weeks, the leachate study expressed that all UIBC and PEBC combinations or single treatments significantly reduced the losses of cumulative nitrate and K compared to the department recommendation, indicating their potential as effective slow- release fertilizers.

Synergistic reinforcement of starch matrices: Investing the combined effect of natural fiber (Banana Peel) and antioxidant (Polyphenol) on bioplastic performance

2026-01-01T00:00:00Z

Title: Synergistic reinforcement of starch matrices: Investing the combined effect of natural fiber (Banana Peel) and antioxidant (Polyphenol) on bioplastic performance Authors: Rudhra Premdharshan, M.; Vasantharuba, S. Abstract: The demand for sustainable materials has driven the use of agricultural residues to develop starch-based bioplastics as alternatives to conventional plastics. This study investigates the combined effect of polyphenol (PP) and banana peel (BP) on starch-based bioplastic properties. Four starch-based formulations were developed: P2B30 (2% PP, 30% BP), P2B60 (2% PP, 60% BP), P4B30 (4% PP, 30% BP), and P4B60 (4% PP, 60% BP), and characterized. Moisture content was highest for P4B60 (36.41±0.16%) and lowest for P2B30 (28.30±0.12%), whereas P2B60 and P4B30 showed intermediate values with significant difference (p<0.05). Thickness was highest for P4B60 (0.97±0.01 mm) and lowest for P2B30 (0.76±0.01 mm), whereas P2B60 (0.85±0.01 mm) and P4B30 (0.91±0.01 mm) were intermediate (p<0.05). Density was 1.12±0.02 (P2B30), 1.15±0.02 (P2B60), 1.17±0.02 (P4B30), and 1.19±0.02 g/cm³ (P4B60) with no significant difference between formulations (p>0.05). Tensile strength was highest for P4B30 (9.30±0.14 MPa) and lowest for P2B60 (5.32±0.13 MPa), whereas P2B30 (7.28±0.11 MPa) and P4B60 (8.45±0.12 MPa) (p<0.05). Elongation was highest for P2B60 (15.55±0.08%) and lowest for P4B30 (6.63±0.09%), whereas P2B30 (12.42±0.10%) and P4B60 (9.18±0.09%) (p<0.05). Total phenolic content (TPC) was highest for P4B60 (1.19 mg GAE/g) and lowest for P2B30 (0.94 mg GAE/g), whereas P2B60 (1.05 mg GAE/g) and P4B30 (1.12 mg GAE/g) (p<0.05). Antioxidant activity (AA) was highest for P4B60 (85.95±0.68%) and lowest for P2B30 (40.79±0.26%), whereas P2B60 (62.34±0.45%) and P4B30 (74.18±0.52%) (p<0.05). Biodegradability was highest for P4B60 (49.2%) and lowest for P2B30 (36.01%), whereas P2B60 (42.15%) and P4B30 (45.83%) (p<0.05). Results demonstrate synergy between natural fibres and antioxidants, supporting renewable bio-components as sustainable plastic alternatives.

Response of rice to silicon application with special reference to phytolith formation, nutrient uptake, growth and yield

2026-01-01T00:00:00Z

Title: Response of rice to silicon application with special reference to phytolith formation, nutrient uptake, growth and yield Authors: Akeela, A.; Gnanavelrajah, N.; Renuka, R. Abstract: Rice (Oryza sativa L.) is a staple food for more than half of the world’s population; however, its productivity is often limited by climatic, biotic, and abiotic stresses. Silicon (Si), a beneficial element for Graminaceous crops, enhances plant resilience, nutrient use efficiency, and overall productivity. One important role of Si is the formation of phytoliths microscopic silica deposits in plant tissues which improve mechanical strength, reduce lodging, increase stress tolerance, and contribute to long-term carbon sequestration through phytolith-occluded carbon (PhytOC). Despite these advantages, comparative studies on soil and foliar Si application are limited. Therefore, a pot experiment was conducted using a completely randomized design (CRD) with seven treatments, including a control, Department of Agriculture (DOA) recommendation, and combinations of soil and foliar Si applications at different rates. The study aimed to evaluate the effects of Si sources and application methods on rice growth, yield attributes, nutrient uptake, phytolith accumulation, PhytOC, and soil nutrient status. Results indicated a non-significant increasing tread in grain yield among Si treatments. However, significant increase (p < 0.0001) was observed in nutrient uptake (NPK), Phytolith and PhytOC in Si treatments especially in DOA+ soil applied silica at 250 kg ha⁻¹. Soil application was more efficient than foliar and 250 kg ha⁻¹ soil applied Si was identified as optimum. Future studies should focus on field experiments under varying agro-climatic conditions and extended crop duration to better capture yield responses. Evaluating Si under induced stress conditions is also suggested for future studies.