http://dr.lib.sjp.ac.lk/handle/123456789/10448 Wed, 07 Jan 2026 03:59:34 GMT 2026-01-07T03:59:34Z http://dr.lib.sjp.ac.lk/handle/123456789/10471 Effect of Various Agroforestry Tree Species on Soil Chemical Properties of Irrigated Tree Plantation of Pakistan Muhammad, Z.A.; Javed, M.A.; Yasin, G. Pakistan is a forest deficient country and natural forests are seriously depleted due to overutilization and lack of proper conservation practices. Agroforestry is being promoted to release the pressure on the natural forests as well as to increase farmlands utility and production. Selecting tree species with the potential to increase soil fertility and offers less competition to the main crops is a fundamental problem. Two exotic species Acacia nilotica, Eucalyptus camaldulensis, and an indigenous species, Dalbergia sissoo were used to understand their role in changing the soil composition under an irrigated plantation environment. Their effect was studied both at different soil layers and under and away from the canopy. All three species significantly affected the chemical composition of the soil. Results revealed that the electrical conductivity, organic matter, N, P, K, and soil moisture were significantly higher under the canopy as compared to away from the canopy. Most of the activity and significantly high minerals were found at 15–30 cm as compared to 0–15 cm soil strata. Dalbergia sissoo is a deciduous tree and produced more leaf litter outperformed A. nilotica and E. camaldulensis. E. camaldulensis suppressed the understory growth of other plant species thus threatening local flora and fauna therefore should not be recommended for plantation on farmlands. D. sissoo a shade-intolerant shall be planted alone or mix with A. nilotica would be a preferred choice as they complement well due to sparse canopy of the latter. D. sissoo is mainly used for timber wood production whereas A. nilotica is used for fuelwood will help cope with the wood supply chain. It is therefore concluded that planting tree species improve the soil conditions positively however selection of the tree species should be done with caution. Agroforestry has the potential to reduce the gap existing in timber wood production in Pakistan. Fri, 01 Jan 2021 00:00:00 GMT http://dr.lib.sjp.ac.lk/handle/123456789/10471 2021-01-01T00:00:00Z http://dr.lib.sjp.ac.lk/handle/123456789/10467 Prediction of the Early Growth of Plantation Grown G. walla Dilrukshi, P.G.T.; Subasinghe, S.M.C.U.P.; Senevirathne, A.M.W.K. Certain tree species of Thymalaeaceae family produce highly fragrant, valuable resin called agarwood inside the stems, branches and roots due to a defence mechanism to protect internal tissue damage from invading microorganisms. Gyrinops walla is the only native tree species bearing the agarwood resin production ability which is growing in the low and mid elevations of wet climates of Sri Lanka. After some years of discovering the ability to produce agarwood resins in of G. walla, private sector investors planned to establish small and medium scale plantations using this species. However, information on G. walla growth rates under plantations conditions were not available, which are essential for the effective management. Therefore the present study aimed at constructing height and diameter prediction models for the early stages of G. walla plantations. For this purse, monthly measured height and diameter data of 40 plants of an even-aged G. walla plantation were used. Several non-linear and 2nd and 3rd order polynomial models were initially tested, keeping age as the single explanatory variable. Among them, the best performances were given by the 2nd order polynomial models for both height and diameter variables. Both models had R2 over 99.0 and root mean square error and mean absolute difference less than 0.10, proving high accuracy. Fitted line plots also did not indicate deviations of the residuals. Though the models built in this study are recommended for predicting the early plantation growth of G. walla, future research should be conducted to validate them till the maturity of the trees. Fri, 01 Jan 2021 00:00:00 GMT http://dr.lib.sjp.ac.lk/handle/123456789/10467 2021-01-01T00:00:00Z http://dr.lib.sjp.ac.lk/handle/123456789/10466 Assessment of Vegetation Index in Selected Protected Areas of Southern Western Ghats, Kerala, India Shalu, G.; Zubereya, K.; Anbazhagi, S. The Western Ghats Forest ecosystem is known for its abundance of flora and is impacted primarily by habitat degradation. The Normalized Difference Vegetation Index (NDVI) was used in this study to assess the vegetation changes over time in three protected areas of Western Ghats, including Idukki Wildlife Sanctuary, Eravikulam National Park, and Parambikulam Wildlife Sanctuary, over a 15-year interval (1988-2003 and 2003-2018) using Landsat datasets and ArcGIS 10.6. The result shows that the vegetation in these three protected areas declined dramatically during a decade (1988-2003), perhaps due to anthropogenic activities, deforestation, forest fires, forest plantations, and fragmentation. Historical records confirm that the study areas have been previously subjected to frequent fires, which have deteriorated the forest. In certain locations, clear-felling of forests for plantation was also documented. Later, between 2003 and 2018, vegetation in these areas increased marginally, possibly due to the Government's conservation efforts in protected areas. Further conservation activities in protected area networks, including afforestation with indigenous flora and adequate legal protection, are recommended in this present study. Fri, 01 Jan 2021 00:00:00 GMT http://dr.lib.sjp.ac.lk/handle/123456789/10466 2021-01-01T00:00:00Z http://dr.lib.sjp.ac.lk/handle/123456789/10463 Value Additions on Iron-Oxide Nanoparticles in Laterite Soils Available in South-West Sri Lanka: Development of Effective Filtering Techniques Dissanayake, N.U.S.; Gunathilake, B.M.; Ranasinghe, S. Environmental contamination by phosphate is on the rise with extensive and diffuse pollution. Answering these badly behaved with serious technologies is very costly. Soil has been commonly used in several wastewater treatment systems and showed to be an in effect substrate for phosphate removal and retention. Using natural sorbent such as laterite could be a way out. The removal of phosphate from aqueous solutions was investigated by using raw laterite in this study. In the adsorption process, the effect of pH, contact time, concentration, adsorbent dosage and salt concentrations were taken into consideration and experiments were carried out in the batch experiment system. Laterite proved to be an effective adsorbent and the removal efficiency remained around 90% of all cases. The optimal dosage was identified as 1g and the removal efficiency was more than 90%. Study of the adsorption as a function of contact time showed that 3 hours was sufficient time for maximum removal of phosphate. Acidic environments of pH values less than 5 facilitated the adsorption of phosphate and the removal efficiency decreased with increasing pH value of the solution. Based on the obtained results from this study, raw laterite is effective in removing phosphate from aqueous solutions and is a cost effective alternative for commercially available adsorbents that are currently used to remove contaminants from drinking water. Fri, 01 Jan 2021 00:00:00 GMT http://dr.lib.sjp.ac.lk/handle/123456789/10463 2021-01-01T00:00:00Z