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Open Access
Wood property profile of rosewood (dalbergia latifolia roxb.) ceylon rosewood (albizia odoratissima (Linn.F) Benth.) and raintree(Samanea saman (jacq.) Merr.)
(Department of Tree Physiology and Breeding,College of forestry, Vellanikkara, 2005) Vinay Kumar, Sahu; KAU; Gopakumar, S
In the state of Kerala, heartwoods of lesser known timber species viz., Albizia odoratissima (Ceylon rosewood) and Samanea saman (rain tree) are allegedly being used as “substitutes” and “adulterants” for making furniture of Dalbergia. latifolia (Indian rosewood) mainly due to their similar wood colour. As this spurious practice has serious implication in timber trade, a study was undertaken to profile the selected wood properties of all these three species to highlight their similarities and differences. The study involved analyzing selected physical, mechanical, anatomical and biochemical properties of A. odoratissima and S. saman and comparing it with the wood properties of D. latifolia as available from relevant literatures. Variations of higher magnitude were noted between the three species for some wood properties, and with respect to few other properties, the differences were lesser. Significant variations were also observed between tissue types viz., sapwood and heartwood for some wood properties. Heartwood tissue types of S. saman and D. latifolia displayed high calorific value, where as, for A. odoratissima both tissue types (sapwood and heartwood) exhibited medium calorific value. The physical properties of the heartwood of A. odoratissima were observed to be higher than that of D. latifolia. S. saman possessed lower values for the physical properties as compared to D. latifolia. Basic specific gravity, radial and volumetric shrinkages (green to oven dry) were considerably different for all the three species. Generally, for both Ceylon rosewood and rain tree tangential shrinkage was higher than radial shrinkage for both the tissue types. Mechanical properties of A. odoratissima were superior to D. latifolia and S. saman, except modulus of elasticity in compression parallel to grain. On the other hand mechanical properties of S. saman were closer to D. latifolia. Measure of fibre stress at limit of proportionality and modulus of elasticity in static bending and modulus of elasticity in compression parallel to grain are considerably different for the three species. In A. odoratissima and S. saman, the mechanical properties of sapwoods varied non significantly with the strength properties of heartwoods. S. saman exhibited superior strength properties for heartwood over its sapwood. Vessel diameter, distribution of parenchyma and ray height can be used to differentiate the three species. In all the species, along the radial axis from pith towards periphery, the vessel diameter, ray height, ray width increased along the region of heart wood. Likewise, ray frequency, and vessel frequency decreased along radial axis in heartwood region. Average vessel diameter, ray height and ray width of sapwoods were greater than that of the heartwoods. Lignin, cellulose and holocellulose percent of A. odoratissima and S. saman were significantly greater than D. latifolia. Higher lignin, cellulose and holocellulose content are responsible for the higher strength properties of A. odoratissima. Methanol-acetone extracts of heartwood of D. latifolia exhibits specific peak wavelengths under spectrometric analysis, which are not found in the other two species. Phenolic compounds were observed to influence some of the physical properties.
Open Access
Morphological and anatomical properties of teak seedlings as influenced by nursery techniques
(Department of Tree Physiology and Breeding, College of Forestry,Vellanikkara, 2004) Girija Pushpom, R P; KAU; Anoop, E V
An experiment was carried out at College of Forestry, Kerala Agricultural University, Vellanikkara with the objective to evaluate the best nutrient levels and sowing treatments required for the production of good quality stumps based on anatomical properties of the seedlings with particular reference to wood formation due to cambial activity. The different nutrient and sowing methods were randomly allocated following completely randomized design. From the experiment, it was found that the best nutrient and sowing method combinations were N2S3 (cowdung 0.4 kg/rrr' and neem cake 0.2 kg/rn ' with spacing of 12 cm x 12 cm between seeds). In terms of biometric characters and biomass characteristics of seedlings it was also found that in quick growing seedlings, vessel diameter was large and vessel frequency was less. Collar girth was positively related with ring width and negative related with vessel frequency. Comparing the performance of nursery raised seedlings with root trainer raised seedlings it was found that the growth characteristics as well as the anatomical properties were inferior for root trainer raised seedlings. In the present study it was found that the best quality teak stumps could be produced by intensive cultural practices. Intensive management of nursery seedlings could produce VlgOurOUS seedlings and thereby it could produce good quality stumps in less time. Results of the present study showed that traditional system of production of teak stumps were efficient By imposing superior nutrient and sowing methods good quality, vigorous stumps can be produced to meet the immediate plantation requirements within a short period.
Open Access
Diversity of small mammals in the Parambikulam wildlife sanctury
(Department of Wild Life Sciences, College of Forestry, Vellanikkara, 2003) Lekshmi, R; KAU; Ambika Varma, B
A detailed study was conducted in the Parambikulam Wildlife Sanctuary during 1999-200 I to prepare an inventory and to estimate the abundance of small mammal fauna in diverse ecological habitats of the Parambikulam Wildlife Sanctuary. In this study, a total of twenty seven species of small mammals belonging to eight orders were recorded from the Parambikulam Wildlife Sanctuary. Among the eight orders Rodentia was represented maximum with eleven species followed by Carnivora with ten species, remaining orders represented only by a single species. While comparing the rodents trapped from different habitats, natural forest account for more number of species than plantation and vayal. The most common rodent species in the three habitats was Rattus rattus, whereas Golunda ellioti (Indian bush rat) was found only in the moist deciduous natural forest because of the favourable ecological conditions prevailing there. Maximum diversity was more in the natural forest than in plantation and vayal whereas species richness was more in vayal followed by plantation and natural forest. The relative dominance was also high in natural forest than plantation and vayal. Correlation between floral diversity and rodent species indicates that natural forest with more number of plant species possessed high rodent species richness. The ideal conditions prevailing in the natural forest would have helped the survival of rodent species. The lack of ideal conditions in the plantation and vayal would have been the reason for lesser number of rodent species.
Open Access
Zonation,leaf phenology and litter dynamics of mangrove forest at Puduvyppu
(Department of Tree Physiology and Breeding, College of Forestry,Vellanikkara, 2003) Ajay Dattaram, Rane; KAU; Asokan, P K
As species distribution along the sea-land interface to the land interior IS attributed to gradients in soil electro-chemical properties and tidal frequency and nutrient cycling in a system is dependent on litterfall and decay dynamics. Hence, the study for estimating zonation pattern and regeneration status of species along the ocean-land interior trans~cts, along with litter dynamics (literfall and litter decay) was carried out at Puduvyppu mangrove forest. Zonation pattern of species was revealed by carrying out phytosociological analysis along the land-ocean transect and correlating with gradients in electro-chernical properties of soil. Litterfall was studied by evaluating interzonal and monthly variations in litterfall between species for one year. Leaf fall and production was inturn correlated with weather parameters. Decay dynamics was studied by involving six predominant species of the forest namely, Avicennia officinalis, Bruguiera cylindrica, Rhizophora mucronata, Sonneratia caseolaris, Acanthus ilicifolius and Excoecaria agallocha and by estimating interzonal and monthly variations in mass loss and nutrient concentrations of decomposing leaf samples for 12 months. Results show that the area can be divided into three zones (zone I: 0-300 m, zone U: 301-800 m, zone Ill: 801-1200 m from the sea) based on species distribution pattern. Species diversity along the zones decreased from zone I to zone I I, whereas, phytosociological para~1eters of species increased. It was also observed that species like R. mucronata and S. caseolaris were restricted in zone I, whereas, A. officinalis and B. cylindrica were abundant towards the landward side, due to the tidal sorting of the species. Electrical conductivity and soil nutrient (N, K, Na) concentrations increased towards the landward side, whereas, pH decreased. Furthermore, soil P concentrations and in situ redox potential positively affected stand density and E. agallocha stand density respectively. Regeneration was profuse in the central zone of the forest (700-800 111 from the sea) and decreased towards the landward side and the seaward side, implying that monospecifity and tidal inundation affected regeneration. Among the species, A. officinalis seedlings were abundant in the lower height class «50 cm) and B. cvlindrica in upper height class (>50 cm), implying that shade tolerance of the species decided its establishment potential. Litterfall did not vary among the zones suggesting that the dominant A. officinalis determined litterfall of the forest. Leaf fall peaked during winter season (November-December), whereas, leaf production was initiated by rainfall, implying that rainfall and temperature controlled phenological cycles in species. Mass loss followed an exponential pattern in A. ilicifolius, A. officinalis. E. agallocha and S. caseolaris, whereas, it followed a linear pattern in B. cylindrica and R. mucronata. Similarly decay rates were inversely related with initial lignin and lignin: nitrogen ratio of the decomposing leaves. And also, interzonal variations in decay rates were observed, implying that site and species affected decay rates. Nutrient concentrations decreased with Nand K concentrations decreasing and P moderately increasing in the litter bags during the course of decomposition, implying that tidal frequency and mineralization-immobilization frequencies decided nutrient release patterns in these species. In general this is a low diversified, juvenile with an efficient nutrient input-out put mechanism.
Open Access
Influence of soil moisture regimes and stage of host introduction on seedling growth of sandal provenances
(Department of Tree Physiology and Breeding, College of Forestry, Vellanikkara, 2004) Vijayakumar, J Hiremath; KAU; Ashokan, P K
The influence of soil moisture regimes and stage of host introduction on seedling growth of sandal provenances was investigated in a pot culture experiment at the College of Forestry, Kerala Agricultural University, Vellanikkara. Two provenances in the South India, Shimoga (Karnataka) and Marayoor (Kerala) were selected for this study. The results showed that the seedlings of Marayoor provenance were taller and having a higher collar diameter as compared to seedlings of Shimoga provenances. The stage of introduction of host did not have any effect on the growth of sandal seedlings. The seedlings where the host was introduced at the time of planting sandal had comparatively higher total chlorophyll in both the provenances as compared to seedlings where the host was introduced three and six months after planting sandal. Highest Nitrogen and Calcium content was observed in Marayoor provenance when the host was introduced at the time of planting sandal, whereas the P content was higher in both the provenances where the host was introduced at the time of planting sandal. The parameters like seedling height, collar diameter, number of leaves, leaf area, dry matter and chlorophyll content decreased due to water stress. The haustorial connections were found only at 300 days after planting sandal. The seedlings of Marayoor 'provenance recorded lower pre-dawn water potential as compared to seedlings of Shimoga provenance. Introducing host at the time of planting sandal or three months after planting sandal, in Marayoor provenance resulted in higher plant water potential. The leaf diffusive resistance was relatively high in Marayoor provenance when the host was introduced at the time of planting sandal. The leaf diffusive resistance was high in water stressed plants. As the haustorial connections were found only at 300 days after planting sandal, it can be concluded that the host need to be planted only six to nine months after planting sandal. This will avoid the early competition between sandal and host. Fast growing pot host during the early phase of its growth may suppress sandal by competition.
Open Access
Biomass production and nutrient accumulation in an age series of caesalpinia sappan Linn. plantations
(Department of Forest Management and Utilisation, College of Forestry, Vellanikkara, 2006) Imrose, Elias Navas E; KAU; Vidyasagaran, K
The present study was conducted at College of Forestry, Kerala Agricultural University, Vellanikkara on biomass production and nutrient accumulation in an age series (5, 6 and 7) of Caesalpinia sappan plantations in three districts of Kerala. The study reveals that diameter, height, biomass, productivity and volume increased with increasing age. The above ground biomass and biomass components also increased with increasing ages. The above ground biomass produced was 23.81 t ha-1 at 5 year, 37.80 t ha-1 at 6 year and 44.36 t ha-1 at 7 year. The productivity at age 5 year was 4.77 t ha-1yr-1, at age 6 year 6.30 t ha-1 yr-1 and at age 7 year was 6.34 t ha-1 yr-1. The increase of the productivity between 6 and 7 years were very low (0.04 t ha-1yr-1), which indicated that no further increase in the productivity of the trees. It highlights that a levelling off the productivity beyond 6 year. This consideration suggests 6 year as the optimum harvesting period of C. sappan. The percentage contribution of various components to above ground biomass was in the order: bole > branch > twig > fruit > leaves> bark. The biomass components were also showed an increasing trend. The prediction equations were prepared for above ground biomass as well as biomass components with respect to dbh and height. Even though some equations were proved more fit with combination of dbh and height, R2 value and Furnival index were relatively similar to equations with dbh alone could not be selected, it is difficult to measure height of the standing trees with definite accuracy. Hence, equations with dbh alone were selected for predicting the biomass. With respect to the dbh alone as independent variable, the total above ground biomass, the best fit equation was W = b0 +b1 D+ b2 D2. In leaves also this model proves as best fit. The components like bole, bark, branch and fruit, the best fitted equation was ln W =b0 + b1 ln D. But in twig, it was W=b0 + b1 D2. Weight table prepared for bole (UB) and total above ground biomass based on the best fit equation using diameter at breast height The nutrient concentration was increased with increasing age except in bole and branches. Concentration in bole and branches increased from 5 to 6 year and decreased from 6 to 7 year. Leaves had the maximum concentration of the nutrients and bole the lowest. The nutrient accumulation of the above ground biomass as well as biomass components increased with the increasing age of plantation. The maximum nutrients accumulated in bole and minimum in bark. Among the nutrients, N accumulated maximum followed by K and P. Nutrient use efficiency increased with increasing ages. The maximum nutrient use efficiency observed for P followed by K and N. It was found to be maximum in bole and minimum in leaf.
Open Access
Screening of tree species for growth behaviour, biomass and wood properties
(Department of Forest Management and Utilisation, College of Forestry, Vellanikkara, 2006) Arun, Gupta; KAU; Gopikumar, K
The present study was conducted in College of Forestry, Kera1a Agricultural University, Vellanikkara to evaluate the growth performance, biomass production, physical properties of wood and leaf nutrients of selected tree species grown in the arboretum during the period 2004-2006. A total of ten species were included in the study with an objective of screening the promising species for their further multiplication in the college nursery on large scale for distribution to farmers for farm/agro forestry and general afforestation programme. The results revealed that among the species studied, species like Terminalia tomentosa, Terminalia bellerica, Acacia auriculiformis and Acacia mangium were found fast growing in terms of height and girth. Grevellia robusta, Artocarpus hirsutus etc. showed lowest increment in height and girth. Artocarpus hirsutus produced highest number of branches followed by Grevellia robusta. Number of branches did not differ significantly among other species. The total biomass production was found to be maximum for Terminalia tomentosa while the lowest total biomass was produced by Swietenia macrophylla in terms of both fresh and dry weight. The least dry weight for trunk was also recorded for Swietenia macrophylla followed by Artocarpus hirsutus. Trunk accounted for maximum biomass production followed by branches. The contribution of trunk was followed by branches in all the tree species except Grevellia robusta and Terminalia bellerica where the dry weight of twigs was more than that of branches. Acacia mangium and Acacia auriculiformis produced more heartwood compared to other species. Acacia mangium, Acacia auriculiformis and Swietenia macrophylla could be used for small timber purpose as they showed higher heartwood - sapwood percentage ratio. Swietenia macrophylla recorded maximum bark percentage closely followed by Terminalia tomentosa. Terminalia bellerica, Artocarpus hirsutus and Acacia auriculiformis, were having high calorific values and hence could be used for fuel wood purpose also. Specific gravity was found to be maximum for Swietenia macrophylla and minimum for Terminalia bellerica. Leaf tissue nitrogen content was significantly highest in Ailanthus triphysa followed by Acacia mangium and Xylia xylocarpa. The phosphorus content was found to be maximum in Ailanthus while potassium in Tectona grandis. Leaves of Xylia xylocarpa were found to record minimum content of phosphorus and potassium.
Open Access
Performance of multipurpose trees in coconut based agroforestry systems and their influence on soil physico-chemical and biological properties
(Department of Tree Physiology and Breeding,College of Forestry, Vellanikkara, 2006) Srinivasan, K; KAU; Ashokan, P K
An experiment was conducted to study the effects of intercropping of three fast growing MPTs viz. Casuarina equisetifolia, Ailanthus triphysa and Leucaena leucocephala in coconut plantations, on soil physico-chemical and biological properties; the field experiment was laid out at the Instructional farm, Kerala Agricultural University, Vellanikkara. The influence of three water harvesting structures viz. simple pits, contour trench and ring trench, which were established in the seedling phase were also compared. The experiment was laid out during 1993 in one year old coconut plantation spaced at 7 x 7m .The MPTs were planted between rows of coconut at a spacing of 2.33 m. The experiment was laid out in Randomised Block Design (RBD), with three replications. The result showed that casuarina recorded maximum height (28.02 m) and girth (GBH of 71.76 cm) and biomass accumulation among different MPTs studied. Ailanthus intercropped systems intercepted about 93 percent available sunlight and control plots (coconut alone) intercepted the least with around 57 percent due to their stand leaf area index of 3.21 and 1.52 respectively. It was observed that MPTs had an adverse effect on the productivity of coconut during later stages of the cropping system. MPTs had tremendously increased the water holding capacity and infiltration rate of the soil. Ailanthus interplanted plots showed better water holding capacity and improved the infiltration capacity of the soil. Resorting to agroforestry practices considerably increased the organic carbon content of the soil. Casuarina interplanted plots showed higher available N, P and K and the surface layer had more concentration of available nutrients. As the soil depth increases the available nutrient concentration was found to decrease. Microbial population viz., bacteria, fungi and actinomycetes were also found to increase due to the influence of MPTs intercropped in coconut plantations. The microbial population viz. bacteria, fungi and actinomycetes was found more in coconut intercropped with casuarina plots. Fungi and bacterial population were found more in the 30-45 cm soil layer but actinomycetes was found more in the surface layers. The percentage of VAM infection on the roots was also seen more in casuarina intercropped in coconut garden.
Open Access
Ecology of the birds of the high altitude grassland-shola forests
(College of Forestry, Vellanikkara, 2001) Radhakrishnan, P; KAU; Nameer, P O
The shola forests are unique montane vegetation occupying temperate habitats in tropical latitudes and are regarded as relict communities. These forests are high altitude gallery forests restricted to valleys, depressions and especially along folds of hills and watercourses. The shola-grassland ecosystem is unique vegetation type found in Western Ghats. Unfortunately very few studies have been conducted on the fauna and flora of this unique ecosystem, particularly avifauna. A study was conducted to give some insight into the birds of the shola-grassland ecosystem and their association with the vegetation of the high altitude area. The study was conducted at the Mannavan Shola of the Marayur range, Munnar division Kerala (10° 10' to 10° 12' N latitudes and 77° 09' to 77° 12' E longitudes), which is the largest shola forest area of the Kerala State. Two study sites were identified in the study area, such as "Shola upper" and "Shola lower". The distance sampling method was used in equidistant points identified at each study sites in a 1000 m transect and the points were periodically monitored. Apart from the birds the vegetation structure of the study location was also studied to understand whether there is any relationship occur between the birds and the vegetation. Total of 41 species in 8 orders and 17 families have been reported from the Mannavan Shola. This includes 26 species of resident birds, out of which 8 are endemic to Western Ghats, and 7 species that are long distance migrants. The different measures like the richness, the and the diversity indices, difference. evenness locations shown any significant the two study The similarity indices worked out were also shown that the both sites are much similar. It was also found that the most abundant bird species were the denser species also. The correlation study shown that, bird species richness, bird diversity and bird density correlated negatively with different structural parameters of the vegetation. Another notable observation was that the high altitude grassland dependant species were totally absent from the study sites. This could be owing to the conversion of the grasslands in the study site to wattle plantation.

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