Journal of Tropical Forestry最新文献

{"title":"Geo-informatics Techniques for Assessing Physiological Status and Productivity of RRIC 121 Genotype of Hevea brasiliensis (Rubber) under Different Harvesting Systems","authors":"K. Fernando, H. Premasiri, K. Kudaligama","doi":"10.31357/JTFE.V6I2.2939","DOIUrl":"https://doi.org/10.31357/JTFE.V6I2.2939","url":null,"abstract":"Abstract Rubber (Hevea brasiliensis) one of the main plantation crops in Sri Lanka is the only plant species cultivated commercially for natural rubber harvesting. Novel systems for harvesting have been introduced but spatial distribution of photosynthetic potential determining key factor for sustainable cultivation has not been properly explored. Use of such techniques such as Satellite Remote Sensing (RS) and Geographic Information System (GIS) to analyse spatial and biological factors related to the productivity of rubber plantation with different harvesting systems is the main objective of the present study. Quikebird high resolution satellite images were used for RS analysis. Chlorophyll content of rubber leaves was measured using a SPAD-502 chlorophyll meter. Chlorophyll content and satellite images were analysed using GIS and spatial statistical methods to determine the variation in different harvesting systems. Yield data were collected from the study site and yield parameters were correlated with chlorophyll content and Normalized Difference Vegetation Index (NDVI) values. Results revealed all systems exhibited promising yield performance without significant deviation but slightly higher yield per hectare per year (YPH) and dry rubber content of latex (DRC) were recorded in quarter spiral based once in three days (S/3 d4) and weekly (S/2 d1 2d7) harvesting systems. Chlorophyll content and rubber yield showed direct correlation in all systems. NDVI vs chlorophyll showed positive correlation r2=0.65 and spatial distribution of chlorophyll and NDVI values demonstrated sound physiological status of plants across the plantation with different harvesting systems. Cost effective LIH systems showed better production trend demonstrating relatively higher yield while reducing tapping cost and labour. Satellite based remote sensing technique is an easy and efficient tool to estimate productivity of rubber plantation over a large area. Keywords: Chlorophyll, NDVI, harvesting, Remote Sensing, Rubber.","PeriodicalId":17445,"journal":{"name":"Journal of Tropical Forestry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2017-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75756326","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Forest Wealth and Global Health","authors":"R. Wijesekara","doi":"10.31357/JTFE.V6I1.2773","DOIUrl":"https://doi.org/10.31357/JTFE.V6I1.2773","url":null,"abstract":"Forest ecosystems are the arsenal that supplies food and medicines for those who are the poorest members of the global community. These are referred to as “forest dwellers”. However the extent of those who depend on the products of the forest go well beyond these humble forest dwellers. In the modern context the forest ecosystems contribute to the diets and the medicines of even urban populations. This being so the widespread destruction of tropical rainforest ecosystems and the consequent extinction of plant and animal species that is ongoing, brings forth consequences that are of mind-boggling proportions. Though tropical moist rainforets are estimated to cover just only 6% of the surface of the earth, they contain an estimated 50% of all species of plants and animal life. The abundant botanical resources of the rainforests have provided mankind, and even neanderthal man, with food and medicines over several millennia. Yet it is just only 1% of this vast resource that has been scientifically evaluated for medicinal potential. At the same time an estimated 2% of the global rain forest resources are irreparably damaged each year, a rate which seems likely to witness the destruction of a possible 20- 25% of the present species of flora and fauna, in a decade from now.. The rain forest resources are the basis on which the traditional medical systems have thrived. Medical systems such as the old Arabian-Greek systems from which modern western medicine is derived, the Traditional Chinese Medicine (TCM), the Ayurvedic, Siddi, and Unani systems, all depend substantially on plants for their therapeutic armoury. Therefore the safeguarding of the resource which is so vital to global health becomes a major reponsibility of mankind. Download Paper (pdf)","PeriodicalId":17445,"journal":{"name":"Journal of Tropical Forestry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2016-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84060104","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A study on the Phytoremediation Potential of Azolla pinnata under laboratory conditions","authors":"Upekha Mandakini Lenaduwa Lokuge","doi":"10.31357/JTFE.V6I1.2626","DOIUrl":"https://doi.org/10.31357/JTFE.V6I1.2626","url":null,"abstract":"Heavy metal contamination in aquatic environments has become one of the major environmental problems all over the world. Phytoremediation is a plant based technology that utilizes special plants known as hyperaccumulators to purify heavy metal contaminated sites. Hyperaccumulators are capable of absorbing heavy metals in greater concentrations.  Azolla pinnata is an aquatic macrophyte that has been earmarked for its hyperaccumulation ability. This green technology is often more favoured over conventional methods due to its low cost, low environmental impacts and wider public acceptance. This study was conducted under laboratory conditions to assess the ability of A. pinnata for the removal of Cr, Ni, Cd and Pb through rhizofiltration, which is one of the phytoremediation strategies under laboratory conditions. Under three main experiments, the fern’s phytoremediation ability was investigated. In the first experiment, A. pinnata was exposed to prepared solutions of Cr, Ni and Pb of 2ppm, 4ppm, 6ppm, 8ppm and 10ppm and of Cd solutions of 0.5ppm, 1.0ppm, 1.5ppm, 2.0ppm, 2.5ppm and 3.0ppm respectively. Experiments were carried out separately for Cr, Ni, Cd and Pb concentrations for 7 days. The concentrations of heavy metals used in the experiments largely agreed with the environmentally measured values, although in certain experiments, the initial concentrations exceeded the environmental pollution levels. The presence of Cr, Ni, Cd and Pb caused a maximum inhibition of A.pinnata growth by 47%, 54%, 52% and 45% respectively while the highest removal percentages of Cr- 98%, Ni- 57%, Cd- 88% and Pb- 86% were recorded in 2ppm, 2ppm, 0.5ppm and 8ppm treatments respectively. The highest Bio Concentration Factor (BCF) for Cr was 1376.67 when treated with 6ppm, 684.95 at 4ppm for Ni, 1120.06 at 0.5ppm for Cd and 1332.53 at 8ppm for Pb respectively. At the end of the experiments toxic symptoms were observed in plats exposed to Cd and Ni. The findings of this experiment revealed that A. pinnata is an excellent candidate for the removal of Pb and Cr even at higher concentrations and for Cd at lower concentrations while it is only partially efficient for Ni removal. The ability of A. pinnata to remove Cr, Ni, Cd and Pb from open dump site leachate was investigated in the experiment two. A. pinnata was exposed to a leachate dilution series of 5%, 15%, 25%, 50%, 75% and 100%. For all four metals, the highest removal percentages as well as the highest BCFs were given by the plants exposed to 5% leachate concentration. The maximum removal percentages were 70%, 52%, 50% and 72% and highest BCFs were 1248.51, 1199.19,867.33 and 1355.43 for Cr, Ni, Cd and Pb respectively. Growth of the fern was limited by around 90% when exposed to leachate treatments. The influence of interactive effects of Cr, Cd, Ni and Pb on their removal capacities of Azolla pinnata and the metal selectivities were determined bythe experiment three. Two treatments were prepared based on the findi","PeriodicalId":17445,"journal":{"name":"Journal of Tropical Forestry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2016-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90443063","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of pre-sowing treatments on seed germination and initial seedling growth performance of Canarium resiniferum: A native threatened tree of Bangladesh","authors":"G. Hasnat, M. K. Hossain, M. K. Bhuyian, M. Alam, Md. Akhter Hossain","doi":"10.31357/JTFE.V6I1.2611","DOIUrl":"https://doi.org/10.31357/JTFE.V6I1.2611","url":null,"abstract":"Canarium resiniferum is an economically and aesthetically important native threatened tree species of Bangladesh. In natural condition 78.5 - 98.7% seeds do not germinate due to seed predation. A study was conducted in the Seed Research Laboratory and nursery of Institute of Forestry and Environmental Sciences Chittagong University, Bangladesh in 2013 to find out appropriate pre-sowing treatment for maximizing germination and initial seedling growth. Eleven pre-sowing treatments were provided in both the seeds sown in polybags and seeds sown in propagator house. Results revealed that, germination started at first (after 20 days of seed sown) in seeds immersed in cold water for 24 hours and germination completed within 38 days. Significantly higher (p<0.05) germination percentage (33%), germination energy (16.7%), plant percent (33%) and germination value (0.4) was found with seeds immersed in cold water for 24 hours. Seedling height measured at three, four and five months after the seed germination in case of seeds treated by immersion in cold water for 24 hours was also greater than others. Therefore, pre-sowing treatment by immersion in cold water for 24 hours was more effective in germination and production of quality vigor seedling of Dhup ( C. resiniferum ).","PeriodicalId":17445,"journal":{"name":"Journal of Tropical Forestry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2016-11-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83891631","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Morpho-Physiological Dynamics of Weedy Rice Seeds Collected from Two Contrasting Agro-Ecological Zones in Sri Lanka","authors":"D. Ratnasekera, K. Rupasingha","doi":"10.31357/JTFE.V5I2.2662","DOIUrl":"https://doi.org/10.31357/JTFE.V5I2.2662","url":null,"abstract":"Weedy rice ( Oryza sativa L. f . spontanea ), seeds remain a longer period in soils at different depths enriching soil seed bank and that contribute to the success of weedy rice as a “weed.” Hence basic information on the level of longevity, dormancy and germination behaviour of weedy rice seeds with relation to its morphology is very important to implement efficient control measures. In this study, weedy rice seeds were collected from six infested locations in Ampara and Matara districts representing two different agro-ecological zones in Sri Lanka. Two widely grown improved varieties (At 362 and Bg 379-2) were assembled as check lines. Thirty panicles per population were randomly collected from each location to determine their morphological characteristics including awn lengths, seed shape, hull colour, pericarp colour along with physiological phenologies such as degree of dormancy, viability, longevity and rate of survival. Significant variability of seed shape, awn length, hull colour and pericarp colour was observed. Germination rate and survival rates were highly variable and closely associated with awn characteristics. Our study clearly indicated that prolong longevity (more than 24 weeks) and viability of weedy rice seeds in field conditions implying their key role as a weed by enriching soil seed bank. Awned populations are dormant and influence weedy rice population dynamics leading to the competitiveness of this weed. Therefore, management practices have essentially to take them into account and be adapted accordingly. Further, this study inferred that the morpho-physiological variation of the weedy rice seed populations was not associated with the agro-ecological conditions; for example, the dry and the wet zone suggesting rapid seed mediated gene flow throughout the country.","PeriodicalId":17445,"journal":{"name":"Journal of Tropical Forestry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2015-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80132735","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimisation of Environmental Factors on Oil Degrading Bacteria Isolated from Coastal Water and Sediments in Sri Lanka","authors":"G. Liyanage, P. Manage","doi":"10.31357/JTFE.V5I2.2655","DOIUrl":"https://doi.org/10.31357/JTFE.V5I2.2655","url":null,"abstract":"Better understanding of the mechanisms of hydrocarbon degrading microorganisms and effect of some environmental factors is critical for the optimisation of the bioremediation processes. Temperature, pH, nitrate and phosphate are the major factors that influence there mediation process of bacterium. In the present study, optimisations some selected physico-chemical parameters (temperature, pH, nitrate and phosphate) were carried out on Bacillus cereus, Enterobacter sp . and Enterobacter ludwigii which were previously isolated as potential oil degraders . The bacteria showed maximum degradation of crude oil at 33 o C where the desirable pH was 8.6 for all the isolates except E. ludwigii (pH 5.4). A significant degradation ( p < 0.05) of oil was detected by B. cereus (80% to 98%), Enterobacter sp. (73% to 90%) and E. ludwigii (70% to 83%) respectively with increasing of nitrate concentration from 0.1 to 2.5 ppm. Significant degradation of oil was not detected in the control and when bacteria were enriched with phosphate. Results of this study revealed that the bacterial remediation of oil is governed by nutritional status with special emphasis of nitrate enrichment in the environment. Thus, the results revealed that bacteria could be a useful tool to remove oil from the contaminated environment as eco-friendly, low cost application.","PeriodicalId":17445,"journal":{"name":"Journal of Tropical Forestry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2015-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78917562","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Potential of Biomass Based Electricity Generation in Sri Lanka","authors":"K. Ariyadasa","doi":"10.31357/JTFE.V5I2.2654","DOIUrl":"https://doi.org/10.31357/JTFE.V5I2.2654","url":null,"abstract":"Biomass has attracted much attention as a primary energy source for electricity generation due to its potential to supply low cost fuel source with considerable environmental and socio-economic benefits. Despite having favorable climatic conditions to grow and use biomass for electricity generation, biomass based electricity generation in Sri Lanka is lagging behind due to many reasons. Many countries rely on the agricultural or forestry by-products or residuals as the main source of biomass for electricity generation mainly due to the comparatively low cost and sustainable supply of these by-products. Sri Lanka does not have this advantage and has to rely mainly on purposely grown biomass for electricity generation. Development of short rotation energy plantations seems to be the best option available for Sri Lanka to produce biomass for commercial scale electricity generation. The highly favorable growing conditions, availability of promising tree species and a variety of plantation management options and significant environmental and socio-economic benefits associated with energy plantation development greatly favor this option. This paper examines the potential of using plantation grown biomass as a fuel source for electricity generation in Sri Lanka.","PeriodicalId":17445,"journal":{"name":"Journal of Tropical Forestry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2015-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84875990","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Greenhouse Gas Emissions from Plantation to the Proceeded Wood Products via State Timber Corporation Depots for Selected Tree Species using Life Cycle Assessment","authors":"D. Senadheera, D. Ranasinghe, W. Wahala, H. Amarasekera","doi":"10.31357/JTFE.V5I2.2660","DOIUrl":"https://doi.org/10.31357/JTFE.V5I2.2660","url":null,"abstract":"Life Cycle Assessment (LCA) provides a methodological framework for evaluating environmental performance over the life cycle of a product, process, or an activity. In Sri Lanka, majority of timber for wood based industries comes from homegardens and Government owned forest plantations. State Timber Corporation (STC) is the authoritative body for timber harvesting in state owned forest plantations. This LCA study was carried out to calculate Greenhouse Gas (GHG) emissions of the STC timber movements from the plantation to the finished product. The study concentrated on teak, eucalypt and mahogany species as they represented fast moving commercial timber of high significance. Assessment boundary was from the harvesting to the product. Updated emission factors were used to calculate the CO 2 eq units. When considering the emissions during the process, the highest was recorded in the sawmilling process (48% from sawing, 9% from surfacing and 9% from drying). The transportation accounted for 31.25% of emissions while harvesting contributed to 6%. Other indirect emissions accounted for 2.75%.","PeriodicalId":17445,"journal":{"name":"Journal of Tropical Forestry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2015-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77515468","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Determination of the Effectiveness of Hal Bark (Vateria copallifera) as a Natural Preservative for Food Security of Confectionery Industry","authors":"Bs Navaratne","doi":"10.31357/JTFE.V5I2.2661","DOIUrl":"https://doi.org/10.31357/JTFE.V5I2.2661","url":null,"abstract":"Hal ( Vateria copallifera ) bark can be used to control sugar fermentation process by yeast. Therefore, it was subjected to sun, mechanical, shade and cooling with dehumidified (CD) drying processes in order to identify the best drying method. 1.5 g of dried bark from four drying processes were introduced into four, 40% sugar (sucrose) solutions to identify the best drying method in terms of froth formation. In addition, 1.5 g of hal bark was introduced into 30%, 40%, 50% and 60% sugar solutions to determine at what sugar concentration that hal bark is capable to control sugar fermentation. Moreover, 0.5, 1.0, 1.5, 2.0 and 3.0 g of bark from the best drying method were introduced into 50% sucrose solutions to determine the level that Hal bark can be incorporated into sugar solutions without changing the sugar taste. Finally, optimum level of Hal bark was introduced into 50% sugar solution and levels of reducing, non-reducing and total sugars against the control were monitored. Sugar solutions were inoculated with 1.0% yeast.","PeriodicalId":17445,"journal":{"name":"Journal of Tropical Forestry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2015-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77677720","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Identification and Quantification of Tree Species in Open Mixed Forests using High Resolution QuickBird Satellite Imagery","authors":"S. Arockiaraj, Amit Kumar, Najmul Hoda, A. Jeyaseelan","doi":"10.31357/JTFE.V5I2.2658","DOIUrl":"https://doi.org/10.31357/JTFE.V5I2.2658","url":null,"abstract":"Present study deals with identification and quantification of tree species within an open mixed forest in parts of Ranchi district Jharkhand, India using high resolution QuickBird satellite data using image processing and GIS techniques. A high resolution QuickBird satellite image was used for shadow enhancement and tree crown area extraction. The First Principal Component of QuickBird satellite images was employed to enhance the shadowed area and subsequently shadow and non-shadow area were classified using ISODATA. The satellite image was used for crown area extraction with standard deviation of NDVI value and the crowns were classified into five classes using Maximum Likelihood supervised algorithm. Result shows that barring few limitation, the high resolution QuickBird image provides rapid and accurate results in terms of identification and quantification of tree species in conjugation with field verification and attained 88% of classification accuracy. It reduces the time required for obtaining inventory data in open mixed forest. Results also showed that total 5,522 trees of various species were present in the study area and dominated by Shorea robusta (80.48%) followed by Ziziphus mauritiana (16.26%), unknown tree (1.81%), Ficus religiosa (0.98%) and Mangifera indica (0.47%). The demography patterns of the locals mainly tribal (89.9%) exhibited their direct as well as indirect dependency on mixed forests resources for their subsistence and livelihood. The study necessitate towards the effective implication of policies to raise the standard of living of tribal people in the region.","PeriodicalId":17445,"journal":{"name":"Journal of Tropical Forestry","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2015-12-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86863597","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}