Homegardens are resourceful ecosystems that provide essential services to the environment and man... more Homegardens are resourceful ecosystems that provide essential services to the environment and mankind. Their contribution to secure household food requirement is among the provisional services of contemporary relevance. A study was conducted in 429 homegardens in Jaffna, Matale, Ratnapura, and Hambantota districts to assess the scope of utilizing homegarden resources on household food security. A questionnaire survey was conducted to gather information on the consumption frequency and the number of food categories that were purchased, produced, and shared. The mean food consumption score (FCS) was 60±23, where 89% of the study population had an acceptable level of FCS (FCS>35). As per the dietary diversity score (HDDS), an average household consumed at least eight food categories per day. Coconut was the most common food commodity produced in homegardens, followed by jackfruit and other fruits (mango, guava, soursop and pomegranate). Households rely on the market-available foods ...
Tree diversity in Asia's tropical and subtropical forests is central to nature-based solutions. S... more Tree diversity in Asia's tropical and subtropical forests is central to nature-based solutions. Species vulnerability to multiple threats, which affect provision of ecosystem services, is poorly understood. We conducted a region-wide, spatially explicit assessment of the
Proceedings of International Forestry and Environment Symposium
Pteridophyte flora represent an important component of natural vegetation and about 362 taxa belo... more Pteridophyte flora represent an important component of natural vegetation and about 362 taxa belongs to 30 families have been described in Sri Lanka. Even though Pteridophytes play a significant role in natural ecosystems, they are one of the least studied plant categories in Sri Lanka. Although majority of Pteridophytes (81%) have been distributed in the wet zone of the country, little is known about the diversity of them even at Sinharaja Forest which provides a natural refugee for many species. Therefore, the objective of this study was to initiate a systematic study on Pteridophytes at Sinharaja Forest with respect to species and habitat diversity. The study was conducted in the Mulawella Mountain. Nine plots of 20×20 m were established randomly along the stream. Each plot was divided to four sub plots. All Pteridophytes growing in each sub plot were identified to species level and their number was recorded. Pteridophyte species observed were categorized according to their life forms. Diameter at breast height of all tree species above 5 cm dbh was measured along with their number. Number of saplings from all tree species was also counted. Point diversity of Pteridophytes was estimated as number of species recorded in each plot of 100 m2 and Shannon-Wiener diversity index was calculated. In addition to plot assessment, all Pteridophytes along the stream and other areas were also identified to species level to prepare the checklist for the area. The study plots and assessments of stream banks and other specific areas documented 63 species belonging to 20 families. Twenty two percent of recorded Pteridophytes in Mulawella area were endemic to Sri Lanka. A check list of Pteridophytes was prepared for the study area. Two extremely rare species namely, Teratophyllum aculeatum and Lindsaea repens were also recorded from the area. A single specimen was recorded which closely resembles Prosaptia ceylanica which is presently limited to a type specimen only at the Kew Herbarium, UK. However, only 28 species (44%) which belongs to 12 families were identified from a total 0.36 ha of randomly selected sample plots. Terrestrial category was the dominant life form with 49% of species at Mulawella mountain area followed by epiphytic (34%) and lithophytic (16%). Only four species were observed in both epiphyte and lithophyte habitats. Elevation of the study area changed from 515 to 750 m amsl, however, the number of fern species and total number of ferns did not show correlation with increasing elevation. Shannon’s Wiener diversity index for individual plots varied from 0.44-1.89. Cumulative number of species showed significant asymptotic relationship with cumulative area surveyed. Based on the results, requirements for future sampling of Pteridophytes have to be developed.
Bulletin of the National Museum of Nature and Science. Series B. Botany, 2014
Dicksonia antartica Labill. is a species native to Australia. In Sri Lanka, until recently, the o... more Dicksonia antartica Labill. is a species native to Australia. In Sri Lanka, until recently, the only known record of D. antarctica was at the Fernery in Hakgala Botanic Gardens, Nuwara Eliya, where the species was planted in 1863. An eco-geographic survey on Sri Lankan tree ferns conducted from 2006–2013 identified a substantial population from Pidurutalagala Mountain Forest Reserve and adjacent Eucalyptus plantation. The detailed observation of population in natural forest and forest plantation fringe revealed natural regeneration with substantial number of immature and mature individuals. Hence, it is proposed that D. antarctica is naturalized in some areas of Pidurutalagala Mountain Forest Reserve and adjacent Eucalyptus plantation after escaping from the Fernery in the Hakgala Botanic Gardens. The substantial amount of population was observed about 30 km away from the Fernery. Further studies on population and reproductive biology are continuing.
The gherkin industry in Sri Lanka has been experiencing a problem of greater pre-mature fruit dro... more The gherkin industry in Sri Lanka has been experiencing a problem of greater pre-mature fruit drop, leading to lower crop production, hence this research was designed to investigate the influence of supplemental lighting on reducing pre-mature fruit drop and increasing fruit yield of greenhouse gherkins. The study was conducted at a commercial scale production greenhouse in the Low Country Wet Zone of Sri Lanka during Yala season (May July), 2012 (Experiment І) and early Maha season (September November), 2014 (Experiment ІІ). In Treatment 1 and Treatment 3, supplemental lighting was provided to extend day length from 5.00 a.m. to 7.00 a.m. and 5.00 p.m. to 7.00 p.m. while in treatment 2, supplemental lighting was provided only under rainy/cloudy weather condition from 7.00 a.m. to 5.00 p.m. In Experiment І, a combination of fluorescent lamps and incandescent lamps were used at the ratio of 2:1, while the same source of lights were used at the ratio of 5:1 for treatment 3 and treatme...
Homegardens are resourceful ecosystems that provide essential services to the environment and man... more Homegardens are resourceful ecosystems that provide essential services to the environment and mankind. Their contribution to secure household food requirement is among the provisional services of contemporary relevance. A study was conducted in 429 homegardens in Jaffna, Matale, Ratnapura, and Hambantota districts to assess the scope of utilizing homegarden resources on household food security. A questionnaire survey was conducted to gather information on the consumption frequency and the number of food categories that were purchased, produced, and shared. The mean food consumption score (FCS) was 60±23, where 89% of the study population had an acceptable level of FCS (FCS>35). As per the dietary diversity score (HDDS), an average household consumed at least eight food categories per day. Coconut was the most common food commodity produced in homegardens, followed by jackfruit and other fruits (mango, guava, soursop and pomegranate). Households rely on the market-available foods ...
Tree diversity in Asia's tropical and subtropical forests is central to nature-based solutions. S... more Tree diversity in Asia's tropical and subtropical forests is central to nature-based solutions. Species vulnerability to multiple threats, which affect provision of ecosystem services, is poorly understood. We conducted a region-wide, spatially explicit assessment of the
Proceedings of International Forestry and Environment Symposium
Pteridophyte flora represent an important component of natural vegetation and about 362 taxa belo... more Pteridophyte flora represent an important component of natural vegetation and about 362 taxa belongs to 30 families have been described in Sri Lanka. Even though Pteridophytes play a significant role in natural ecosystems, they are one of the least studied plant categories in Sri Lanka. Although majority of Pteridophytes (81%) have been distributed in the wet zone of the country, little is known about the diversity of them even at Sinharaja Forest which provides a natural refugee for many species. Therefore, the objective of this study was to initiate a systematic study on Pteridophytes at Sinharaja Forest with respect to species and habitat diversity. The study was conducted in the Mulawella Mountain. Nine plots of 20×20 m were established randomly along the stream. Each plot was divided to four sub plots. All Pteridophytes growing in each sub plot were identified to species level and their number was recorded. Pteridophyte species observed were categorized according to their life forms. Diameter at breast height of all tree species above 5 cm dbh was measured along with their number. Number of saplings from all tree species was also counted. Point diversity of Pteridophytes was estimated as number of species recorded in each plot of 100 m2 and Shannon-Wiener diversity index was calculated. In addition to plot assessment, all Pteridophytes along the stream and other areas were also identified to species level to prepare the checklist for the area. The study plots and assessments of stream banks and other specific areas documented 63 species belonging to 20 families. Twenty two percent of recorded Pteridophytes in Mulawella area were endemic to Sri Lanka. A check list of Pteridophytes was prepared for the study area. Two extremely rare species namely, Teratophyllum aculeatum and Lindsaea repens were also recorded from the area. A single specimen was recorded which closely resembles Prosaptia ceylanica which is presently limited to a type specimen only at the Kew Herbarium, UK. However, only 28 species (44%) which belongs to 12 families were identified from a total 0.36 ha of randomly selected sample plots. Terrestrial category was the dominant life form with 49% of species at Mulawella mountain area followed by epiphytic (34%) and lithophytic (16%). Only four species were observed in both epiphyte and lithophyte habitats. Elevation of the study area changed from 515 to 750 m amsl, however, the number of fern species and total number of ferns did not show correlation with increasing elevation. Shannon’s Wiener diversity index for individual plots varied from 0.44-1.89. Cumulative number of species showed significant asymptotic relationship with cumulative area surveyed. Based on the results, requirements for future sampling of Pteridophytes have to be developed.
Bulletin of the National Museum of Nature and Science. Series B. Botany, 2014
Dicksonia antartica Labill. is a species native to Australia. In Sri Lanka, until recently, the o... more Dicksonia antartica Labill. is a species native to Australia. In Sri Lanka, until recently, the only known record of D. antarctica was at the Fernery in Hakgala Botanic Gardens, Nuwara Eliya, where the species was planted in 1863. An eco-geographic survey on Sri Lankan tree ferns conducted from 2006–2013 identified a substantial population from Pidurutalagala Mountain Forest Reserve and adjacent Eucalyptus plantation. The detailed observation of population in natural forest and forest plantation fringe revealed natural regeneration with substantial number of immature and mature individuals. Hence, it is proposed that D. antarctica is naturalized in some areas of Pidurutalagala Mountain Forest Reserve and adjacent Eucalyptus plantation after escaping from the Fernery in the Hakgala Botanic Gardens. The substantial amount of population was observed about 30 km away from the Fernery. Further studies on population and reproductive biology are continuing.
The gherkin industry in Sri Lanka has been experiencing a problem of greater pre-mature fruit dro... more The gherkin industry in Sri Lanka has been experiencing a problem of greater pre-mature fruit drop, leading to lower crop production, hence this research was designed to investigate the influence of supplemental lighting on reducing pre-mature fruit drop and increasing fruit yield of greenhouse gherkins. The study was conducted at a commercial scale production greenhouse in the Low Country Wet Zone of Sri Lanka during Yala season (May July), 2012 (Experiment І) and early Maha season (September November), 2014 (Experiment ІІ). In Treatment 1 and Treatment 3, supplemental lighting was provided to extend day length from 5.00 a.m. to 7.00 a.m. and 5.00 p.m. to 7.00 p.m. while in treatment 2, supplemental lighting was provided only under rainy/cloudy weather condition from 7.00 a.m. to 5.00 p.m. In Experiment І, a combination of fluorescent lamps and incandescent lamps were used at the ratio of 2:1, while the same source of lights were used at the ratio of 5:1 for treatment 3 and treatme...
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