Corticolous lichens as indicators of forest management regimes in the Dotalugala area of Knuckles mountain range – Sri Lanka

G. Weerakoon1, S. Somaratne2, P.A. Wolseley3 and S.C. Wijeyaratne1
1
Department of Botany, University of Sri Jayewardenepura, Sri Lanka
2
Department of Botany, The Open University of Sri Lanka
3
Department of Botany, The Natural History Museum, United Kingdom

Lichens have been widely considered as bioindicators of forest health and ecological continuity as well as atmospheric pollution. The use of lichens as bioindicators in tropical zones has been hampered by the lack of taxonomic and ecological knowledge. The purpose of the study was to assess the variation of lichen diversity in different forest management regimes under different environmental conditions on the basis that their potential uses as bioindicators of environmental alterations in different habitats in the Knuckles mountain range. The sampling sites were chosen to include pristine forest of montane and sub-montane and six different disturb vegetation types. Lichen species, their frequency and cover values were recorded together with environmental parameters in 20 sites of 100 m2 plots. Ten trees were sampled randomly in each plot. The collected data were analyzed to assess the relationship between lichen diversity and environmental conditions in different forest management regimes using one-way analysis variance, least significant difference- LSD (mean comparison) and Regression tree analysis.

There were 192 lichen species recorded from the natural vegetations, where as 148 lichen species present in the disturbed vegetation types. The results of the study have shown that there is a considerable variation in the lichen diversity along different vegetation types and their degree of disturbance. The statistical analysis revealed a significant variation in lichen diversity between the disturbed and undisturbed vegetation in the area (F = 6.213, df = 1; p ≤ 0.05). Similarly, lichen diversity in different vegetation types also indicated a remarkable variation (F =3.21, df = 7; p ≤ 0.05). The results obtained from regression tree analysis indicated that there were three important variables that determined the lichen diversity of the study area; type of vegetation, altitude and association with other cryptogamic communities.

There are distinct lichen communities associated with tree boles in disturbed forests including weedy taxa and low diversity with few forest lichen species.  The analysis of epiphytic lichen diversity showed significant difference in the natural vegetation and disturbed vegetation.

This may be due to the heterogeneity of microclimatic conditions and specialist lichen communities associated with pristine tropical forests. Thus, there is utmost importance to identify lichen communities that can be use as indicators of reflecting forest health for the purpose of sustainable management.

Invasive alien species in Indian ornamental industry

S. Rameshkumar, K. Manivannan, C.T. Sathappan and J. Padmanaban
Annamalai University, India

Quantum jump of increase in the awareness about global warming and environmental pollution made the mind set of industries, institutions, corporate and even common man to think about finding a solution to it. Establishment of ornamental gardens and green belt development in the surroundings and waste lands is becoming the best option to curtail pollution problems and it has almost been considered as mandate in urban areas. Increased green belt development and gardening activities help the industries and corporate to manage their carbon credit and in turn helps in reducing climate change.  In these green belts and corporate landscapes and even in botanical gardens many alien species are used in larger volumes.

In a survey conducted in nursery pockets and landscape industries of south India evinced the status of alien species that more than 60 per cent of the ornamental species are foreign in origin and few species are Invasive in nature. More than 50 per cent of the landscape architects opted for foreign ornamental plants to be incorporated in their present and future projects and opined it is inevitable to avoid the invasive alien ornamentals as they have preference among the clients. Though many of these plants are well accommodative and have ornamental value, there is a chance for certain highly invasive alien species to become threat for the eradication native species in the locale and may become serious weed as evident from Lantana Sp. and water hyacinth which were introduced as ornamental plants and now being a threat as major weeds in Indian sub continent. Hence it becomes necessary to have check measures to evaluate the invasiveness of the alien species when it is introduced as an ornamental plant.

Diversity and distribution of mangrove flora in the Attaragoda wetland, Galle with some notes on avifauna

B. Jayasekara1, I.R. Wedage2 and P. N. Dayawansa2

Attaragoda is a mangrove wetland situated in the Southern Coast (Latitude: 6° 1′ 60N, Longitude: 80°
15′ 0E), 3km outside Galle. This luxuriant patch of mangrove forest faces immense pressure due to human activities. Diversity and distribution of mangrove species in relation to salinity levels and species
richness of avifauna were studied from January to June 2009The area was subdivided into three zones based on salinity levels. Zone 1 with recurrent tidal effect had a salinity range of 33-40ppt. Salinity of Zone 2 with moderate influence of tides ranged between 26- 32ppt. Salinity of Zone 3 with least influence of tides ranged between 20-28ppt.

Diversity and distribution of mangrove flora was carried out using quadrat (20x20m) sampling technique. Species richness of birds were determined by carrying out line transects and opportunistic observations. Shannon-Weiner Diversity Index (DI) was calculated to describe floral diversity. Twelve species of true mangroves and six mangrove associates were recorded. Out of eighteen species six were known to be introduced to the wetland. Species richness of Zone 1, 2 and 3 were seven (No. of plots sampled; n=7), six (n=3) and five (n=4) respectively. Increased species richness of Zone 1 is due to introduced species of true mangroves: Rhizophora mucronata, Ceriops tagal and Aegiceras corniculatum

Highest diversity and evenness were recorded from Zone 3 (DI=0.42, J=0.78) and lowest diversity was
recorded in Zone 1 (DI=0.23, J=0.46). Dominant species in Zone 1 were Rhizophora apiculata, Excoecarica agallocha and Clerodendrone inerme. Zone 2 (DI=0.33, J=0.46) was dominated by Rhizophora apiculata and Acanthus illicifolius. True mangrove species Sonneratia caseolaris, Avicennia
officinalis, Heritiera littoralis, Luminitzera racemosa and mangrove associate Cerbera manghas
were
recorded opportunistically in Zone 2. Acanthus illicifolius was exclusive to Zone 2.

Avifauna consisted of 35 species, of which, 20 were wetland species. There were nine species of migratory birds including one scarce winter visitor- Malayan Night Heron, indicating that Attaragoda wetland is an important destination for migratory birds. Immediate steps should be taken to assure degradation of this wetland habitat by human interventions.

B. Jayasekara1, I.R. Wedage2 and P. N. Dayawansa2
1Department of Forestry and Environmental Sciences, University of Sri Jayewardenepura,
Sri Lanka 2Department of Zoology, University of Colombo, Sri Lanka

Diversity of medicinal plants in the Mihinthale sanctuary

A. Herath1, C. Karunanayake1 and S. Wijesundara2

Sri Lanka contains an enormous biodiversity of medicinal plants. Flora of Sri Lanka reports that there
are 3368 angiosperms in Sri Lanka, out of which 20% are medicinal. There is a growing demand for medicinal plants in primary health care. However, the local supply of medicinal plants can not meet the
demand. About 80% of the locally supplied medicinal plants are collected from the wild. This has lead
to unscrupulous collection and destructive harvesting. Therefore, the present study focused on identifying and documenting the diversity of medicinal plants in the Mihintale sanctuary.

Since medicinal plants may be trees, shrubs, or herbs complimentary sampling techniques were used in
sampling. Quadrate sizes for each plant category was chosen according to the method described by Sutherland. Therefore 20x20m, 5x5m and 2x2m quadrates were located randomly for trees shrubs and
herbs respectively. Data on floristic composition, plant density, basal area and dominance were collected
according to the method described by Crutis and McIntosh. The DBH values of the entire data set were
used for cluster analysis (SAS 6.12). Floristic diversity and richness were analyzed using Biodiversity
professional 2.0 software package. The Basal area, Relative density and Importance Value Index (IVI)
were analyzed using SAS 6.12.

One hundred and fifty nine medicinal plant species, which belong to 111 genera and 54 families, were
encountered in the study area. Of the medicinal plant species, 48 were trees, 33 were shrubs, 42 were
herbs and 32 were vines. The dendogram between cluster sums of squares showed three distinct vegetation communities: near tank vegetation, relatively undisturbed areas and disturbed areas. Munronia pinnata (Bin kohomba) an endangered species was observed only in the relatively undisturbed community while Salacia reticulata (Kothala himbutu) a threatened species and Vernonia zeylanica (Pupula) an endemic species were observed in all three communities. The species richness of medicinal plants varied from 105 to 55 species per community, the highest being in the near tank vegetation and the lowest in the relatively undisturbed community. Shannon diversity Index (H) ranged from 3.47 to 3.08, Simpsons diversity (D) from 0.073 to 0.051 and Margalef’s diversity index (Dmg) from 12.52 to 8.09. Near tank vegetation ranked first in medicinal plant diversity (H=3.47, D=0.05, Dmg=12.52) followed by, disturbed (H=3.19, D=0.073, Dmg=10.6) and relatively undisturbed (H=3.08, D=0.072, Dmg=5.20) vegetation respectively. Relative densities of medicinal plants of the three communities differ significantly (p=0.035). The total sample area contained 289 medicinal trees with stems >10cm DBH. The diameter size distribution of individuals enumerated showed that 64% of them were below 30cm diameter.

Importance value Index (IVI) of woody individuals of the identified three clusters varied from 115 to 0.69. In disturbed vegetation and relatively undisturbed vegetation one species Drypetes sepiaria showed
a significant dominance over other species. Contrastingly, in near tank vegetation nearly seven species
showed high IVI values. The disturbed site showed the highest pioneer and secondary plant species
while the highest primary species number was recorded in the relatively undisturbed communityIn
conclusion, medicinal plant diversity is very high in Mihintale sanctuary. Therefore, immediate action
should be taken for conservation. Furthermore, integration of medicinal plants into farming system is
advisable to derive economic benefits to the local community as well to minimize over exploitation.

A. Herath1, C. Karunanayake1 and S. Wijesundara2
1Department of Biologcal Science, Faculty of Applied Sciences, Rajarata University of Sri Lanka
2Department of Royal Botanic Gardens, Peradeniya, Sri Lanka.

Herpetofaunal diversity and distribution in Kalugala proposed forest reserve in Sri Lanka

W.M.S. Botejue and J. Wattewidanage

This study reports species richness, abundance and diversity of herpetofauna in the Kalugala Proposed
Forest Reserve (KPFR). KPFR is a primary lowland tropical rain forest, surrounded by secondary and disturbed vegetation due to human activities like cultivation, logging and collecting firewood. Herpetofaunal communities of these different habitats (closed forest, ecotone, home gardens and cultivations) were assessed using visual encounter surveys, transects, quadrates and pitfall traps, and
distribution patterns were compared. A total of 24 amphibian species (~63% endemic and ~33%threatened) and 53 reptile species (~38% endemic and ~30% threatened) were recorded. Herpetofaunal
Diversity of KPFR (Shannon Wiener Index, H= 1.668) is considerably high. Overall 742 individual amphibians were recorded and Fejervarya limnocharis was the most abundant while Ramanella
variegata, Philautus abundus, P. cavirostris, P. reticulatus and P. stictomerus show the least abundance.
In total 1032 individual reptiles were recorded and Hypnale hypnale showed the highest abundance while Ahaetulla pulverulenta, Balanophis ceylonensis, Geckoella triedrus, Ramphotyphlops sp., Typhlops
sp. and Rhinophis sp. showed the least. Reptilian distribution patterns are similar to the amphibian
distribution patterns, with the highest diversity being in the closed forest and the lowest diversity in
cultivations as expected. We did not observe an affect of ecotone (edge effect) in amphibian and reptile
diversity except for ecotone and cultivations for reptiles (Mann-Whitney U-test: Z = 2.01, P =0.044).
Adverse human activities especially illegal encroachment in forest for agriculture practices, logging and garbage dumps of the Kalugala Monastery which located inside the forest are major growing threat
to the local biodiversity in KPFR.

W.M.S. Botejue and J. Wattewidanage
1Taprobanica Nature Conservation Society, Sri Lanka
2Department of Zoology, Open University of Sri Lanka.

How do Sri Lankan shrub frogs Philautus popularis spend their night time: Field observations from Bolgoda wetland complex

H.G.S.K. Dayananda and D.D. Wickramasinghe

Sri Lanka is an amphibian hot spot providing home for 109 species. Nevertheless, studies on ecology and biology of amphibians of Sri Lanka are scarce and behaviour of frogs has drawn even less attention. Philautus popularis (Ranidae, Rhacophorinae; Manamendra-Arachchi & Pethiyagoda, 2005) is an endemic shrub frog which occurs in the low country wet zone. This study attempts to report behaiourl
spectrum of P. popularis in an undisturbed wetland in an urban area. Study site comprised of two locations in Bolgoda south lake wetland complex (790 52’ – 790 59’ north longitude and 060 42’ – 060
51’ east latitude). 

This study was carried out for one months starting from mid June 2009 from 1800 hrs onwards. On each study date, a random path was chosen to walk till a frog was found. The observations were made according to focal animal sampling method, by the naked eye. When an animal was found the total behavioural pattern was studied carefully from a point 1 m away from the frog. Times spent on different
behavioural activities were noted. A total of 64617 seconds (nearly 18 hours) were spent on different
behavioural activities. 

Twenty nine individuals (26 males and 3 females) were studied and seven behavioural events were encountered: acoustic, locomotion, resting (No movements), foraging, agonistic, cleaning and sexual behaviour. Time taken for each behaviour was compiled taking both sexes into consideration. The most
abundant behaviour event was resting without any movement (45% of the total time) but sometimes
they showed feeding in between. When activities are considered, they were found spending more time
for calling (27.1%, males only) and sexual behavior including amplexus (25%). Interestingly, agonistic
behaviour was shown by males and time taken was 2.1% of total. Walking, cleaning, jumping and climbing took a negligible proportion of the total time and were less than 0.2 percent. Calling was observed from 1800-2300 and they were silent from 0130-0530 and then started acoustic signals again.
Perch height of males varied from 40-160 cm from the ground and the highest point was reached around
midnight. Females were always near the ground (5-15cm). Males are territorial and it is likely that their
home range is within a 5m radius.

This shrub frog used minimum time to climbing locomotion pattern and then jumping. The most abundant locomotion pattern was walking, spent 59.6% from the total time for locomotion to the walking. 3 Different perched postures were recorded and climbing position was recorded. Perched height and time has significant relationship respect to both study sites. There is no any preferred plant species for Philautus popularis. They spent 1380 seconds on agonistic behaviour, 2% of the total behavioural observation time. They spent time of 16,200 seconds in amplexing. They hide under leaf litter during
day time.

H.G.S.K. Dayananda and D.D. Wickramasinghe
Department of Zoology, University of Colombo, Sri Lanka.

Distribution and population parameters of selected tree species in Gilimale and Kithulgala Forest Reserve

S. S. Ranathunga and B.M.P Singhakumara

Field surveys have not been carried out in Sri Lanka to gather the population data on critically endangered tree species in their habitats. The population data on the critically endangered tree species are important to understand the present status of the population. In this study, the population data of seven critically endangered tree species were gathered.

Habitat distribution and some population parameters such as stand tables, plant community composition and structure were studied for seven Critically Endangered (CR) tree species found in the Kitulgala and Gilimale Forest Reserves, tropical lowland rainforests in the southwest part of the country. The selected species are Stemonoporus gracilis, S. petiolaris, and Balanocarpus kithulgallensis in Kitulgala and Stemonoporus gilimalensis, S. lancifolius, S. scalarinervis, and Memecylon macrocapum in Gilimale. Balanocarpus and Stemonoporus an endemic genus belong to the family Dipterocarpaceae and
Memecylon macrocapum belongs to the Melastomataceae.

Sampling of vegetation has been carried out in specific habitats for each selected Critically Endangered species. Suitable plots were identified by a reconnaissance survey and 100×5 m plots were demarcated. All the plants below 1 m of height were counted as seedlings; all the plants less than 2 cm of dbh and over 1 m of height were counted as saplings. DBH and heights of trees over 2 cm dbh were measured.

Survey data of the selected tree species are used to calculate the Important Value Index (IVI). Profile
diagrams were prepared for each tree species to show the vertical distribution in their habitats. Distribution maps of these species were prepared using digital data. Sample plots are located in 1: 10,000 digitized maps prepared by the Survey Department, Sri Lanka.

All species show patchy distribution and these patches are found in different parts of the forest topography. Stemonoporus gracilis, S. petiolaris, S. gilimalensis, S. lancifolius and S. scalarinervis show positive stand tables with reverse “J” distribution curves. This indicates that these populations in their habitats are healthy. Balanocarpus kithulgallensis and Memecylon macrocapum are not showing this type of curves, and more sampling has to be carried out to investigate the population structure of these two species.

All these species could be conserved by protecting their natural habitats (in-situ conservation) and only a two species (Balanocarpus kithulgallensis and Memecylon macrocapum) might need both in-situ and ex-situ conservation strategies.

S. S. Ranathunga and B.M.P Singhakumara
Department of Forestry and Environmental Science, University of Sri Jayewardenepura, Sri Lanka.

Baseline Survey on Biodiversity in up country tea estates in Sri Lanka

G.G.T. Chandrathilake1
Conventional tea plantation was assessed in terms of biodiversity in up country tea estates in Sri Lanka. A rapid survey was carried out to document the both faunal and floral diversity associated in selected nine (9) tea estate in Nuwara Eliya district an areas that have not been properly surveyed for biodiversity. Based on vegetation types, physical conditions and edaphic factors, a total of five (5) major habitat types were identified as well managed tea fields, home gardens, forest/fuel wood plantations, abandoned land surface water bodies. All of the land cover is of anthropogenic origin while riparian vegetation (secondary) diminutive beside the numerous streams which originating from summits and flowing along steep valleys. Study started from August to October 2007 and direct observations, indirect observations and reliable information from local people were used to study birds, butterflies and mammals nested within the tea estate ecosystem while direct observation was used to record flora (except ornamental plants and vegetables) in representative habitats.

A total of 73 faunal species were recorded from study areas out of them 41 species of birds, 11 species of mammals, 16 species of butterflies 2 species of fresh water crabs and 3 species of fresh water fish. The birds identified includes seven endemic species (Sri Lanka yellow fronted barbet, dull blue flycatcher, Sri Lanka wood pigeon, Sri Lanka Jungle fowl, crimson-backed flame back, brown capped babbler and Ceylon white eye). Ceylon white eye can be seen in considerable abundance. Among the mammals presented Sri Lanka toque monkey was the endemic species while other nine species native to the Sri Lanka. All the butterflies recorded from the study area are under common and very common categories. The flora recorded from the survey area includes 108 species belonging to 45 families. Most of the trees are introduced planted species while most of herbaceous species encountered are considered as weeds (46). These include 42 species of trees and remaining 62 species of woody shrubs, herbs, grass and 4 species of ferns.

Conventional agricultural practices like application of pesticide, weedicieds and inorganic fertilizer, land degradation due to soil erosion and spread of invasive alien plants were observed as common threats to existing taxa. Introduction of organic tea farming, Agroforestry systems and establishment of riparian vegetation along the surface water bodies will be important factors to the existing and to enhance the faunal diversity within the tea estate ecosystem.

G.G.T. Chandrathilake
1Department of Forestry and Environmental Science, University of Sri Jayewardenepura, Sri Lanka.

Effects of carbofuran on survival and growth of Duttaphrynus melanostictus tadpoles

M.R. Wijesinghe, B.A.D.M.C. Jayatillake and W.D. Ratnasooriya

This study investigated the impact of a commonly used carbamate pesticide, carbofuran, on survival, growth, development and activity of larvae of the Asian Common Toad, Duttaphrynus melanostictus Schneider 1999. Continuous exposure trials of 15 days were conducted using tadpoles of Gosner stages 24-25 with a commercial grade carbofuran (Curaterr 3G). Four concentrations 50, 150, 250 and 500 μgl-1 were tested and treatments and controls (without pesticides) were maintained in triplicate (n=56 per treatment or control). Results revealed that there were marked elevations in mortality in larvae exposed to all tested concentrations as compared to those in the controls. Mortality was, however, not dose-dependent, but depicted a hermetic response, where mortality at 500 μgl-1 (35 %) was much lower than that recorded at 250 μgl-1 (62 %). The 15day LC50 value of D. melanostictus larvae was 190 μgl– 1. In contrast to mortality, the effects on growth, development and activity although pronounced, were  transient. For instance growth impairments were noted until day 7, but the body size of surviving tadpoles were comparable to those in the controls by the end of the trial. Exposure to carbofuran to concentrations of 150 μgl-1 and above also caused several notable morphological aberrations such as swollen heads and thin tails. In particular, the fact that carbofuran induced high levels of mortality at the tested concentrations, which are below the field application levels, suggest that this pesticide may be detrimental to the survival of amphibians inhabiting agricultural landscapes in Sri Lanka.

M.R. Wijesinghe, B.A.D.M.C. Jayatillake and W.D. Ratnasooriya

Department of Zoology, University of Colombo, Sri Lanka.

Diversity and microhabitats of termites in a natural and a secondary forest in Hantane hills, Kandy District

I.I. Hemachandra, 1,2, J.P. Edirisinghe 1, W.A.I.P. Karunaratne 1, C.V.S. Gunatilleke3

Termites (Isoptera) are the most important decomposers in tropical rain forests and are vital in maintaining nitrogen and carbon cycles. They are sensitive to disturbances, especially to forest canopy losses and hence are one of the important bioindicator taxa. The documented termite fauna of Sri Lanka is represented by 58 species in 28 genera. Research studies on termites of forests are few in Sri Lanka. Objective of this study was to determine the species composition, diversity and microhabitats of termites in a selected natural and a secondary forest in the Hantane hills.

The Hantane range is a series of hills, about 432 ha with an elevation between 518-1110 m. During the British period Hantane land was opened up for coffee, tea and rubber plantations. The selected study sites included patches of natural forest at > 1000 m elevation and a secondary forest, comprising mixed species, at elevations between 700-1000 m. A belt transect (2×100 m) was laid in each site for sampling termites. Each transect was divided into 20 (2x5m) sections and each section was sampled by 2 persons for 30 min. The number of encounters with termites (hits) of a given species within a transect was taken as the relative abundance of that species within that transect. An encounter is the presence of a species in one transect section (5×2 m). Termite diversity was compared using Shannon Diversity Index. Termites were also collected randomly from several areas within the two forest types for species determination.

A total of 11 termite species were collected from the two forest types using both methods. They are: from the natural forest Ceylonitermellus hantanae (Holmgren) (soil-wood interface feeder), Dicuspiditermes incola (Wasmann) (soil feeder); and from the secondary forest Odontotermes ceylonicus (Wasmann), O. globicola (Wasmann), O. horni (Wasmann) (all fungus growers and feeders), Nasutitermes fletcheri (Holmgren & Holmgern) (soil-wood interface feeder) and 5 unidentified species of Odontotermes Holmgren ( fungus growers and feeders) . A lower species Diversity Index was obtained for natural forest (H’= 0.683) compared to secondary forest (H’=1.630). The composition of termites species showed a marked contrast with none of the species in the natural forest being represented in the secondary forest and vice versa. The most common species in the natural forest was the endemic C. hantanae and in the secondary forest, the unidentified Odontotermes sp. 2.

A significant observation in both forests was the absence of termite mounds as well as long runways along live trees that lead to arboreal nests. The two termite species recorded from natural forest are subterranean nest builders that inhabit soil. The termites of the secondary forest inhabit soil, leaf-litter and wooden material like, tree stumps, logs, fallen branches and twigs. Termites of the fungus growing genus Odontotermes was confined to the lower altitudes.

A distinct difference in termite species composition, diversity and microhabitats was recorded from the two forest types, suggesting that altitude and temperature, among other factors may be influential environmental variables for termites.

I.I. Hemachandra, 1,2, J.P. Edirisinghe 1, W.A.I.P. Karunaratne 1, C.V.S. Gunatilleke3

1Department of Zoology, Faculty of Science, University of Peradeniya, Sri Lanka2Postgraduate Institute of Science, University of Peradeniya, Sri Lanka3 Department of Botany, Faculty of Science, University of Peradeniya, Sri Lanka.