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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
Stand density manipulation and fertilization studies on teak
(College of Forestry,Vellanikkara, 1991) Gawande, S R; Mohankumar, B
With the object of standardizing the density manipulation and fertilization strategies for teak, a study was carried out at Vellanikkara during 1990-91. The experimental variables consisted of high, medium and low site quality classes (classified on basis of tree heights), three thinning intensities (control, 30 per cent density reduction and 50 per cent density reduction) and three fertilizer levels (control, 50:25:25 kg of N, P2 O5 and K2O ha -1 yr-1, 100: 50:50 kg of N, P2 O5 and K2O ha-1 yr-1). The results indicate that mean height of trees was strongly influenced by density manipulation. The combination of high site quality with medium and heavy fertilizer doses also significantly increased the mean height of trees. However quadratic mean diameter, stand basal area, basal area increment and height increment were not substantially different among the thinning site quality and fertilization regimes. Tree biomass, foliage area and leaf weight allometry were examined for the first time in teak. The results suggest that leaf area and the biomass yield are strongly dependent on the allometry of trees. High sites consistently recorded higher values for estimates of leaf area, leaf biomass and tree biomass. Combinations of high site quality with medium and heavy thinning as well as medium and heavy fertilization recorded high tree biomass yield, foliage area and leaf area followed by medium and low site quality classes. Foliar analyses showed a general increase in leaf nitrogen during summer (May) and a gradual decline of the same during the fall season (August). High site quality with medium and heavy fertilization recorded highest nitrogen content. Thinning on higher sites significantly increased foliage phosphorus and potassium levels. In general the trend concerning nutrient contents of different tree organs followed the order leaves> stemwood> branchwood. Branch wood and stem wood N levels were relatively higher on high sites. Potassium content was, however, greatest in the low sites. Soil nutrient analysis did not indicate any substantial changes in the soil physico-chemical properties consequent to thinning and fertilization which incidentally substantiates Miller’s hypothesis on forest fertilization that fertilizers benefits only the trees and not the sites.
Open Access
Comparative performance of three exotic tree species in social forestry strip plantation in Trichur Social Forestry Division
(College of Forestry,Vellanikkara, 1990) Nandakumar, G; KAU; KrishnanNair, V R
A study was conducted in 1987-88 on the social forestry strip plantation on the premises of the Sitaram Textile mills Ltd. In the Trichur Social Forestry Division of Kerala State; to compare the performance of three exotic fast growing tree species, Casuarina equisetifolia, Acacia auriculiformis and Eucalyptus tereticornis in social forestry strip plantation. Comparisons were made on the three year old plantation in respect of growth, biomass production and impact on the soil and undergrowth. General observations were also made on the tree form, occurance of pests and diseases and wild life habitat improvement. The site of experiment was being used for dumping coal cinders and other wastes from the textile mill and was barren before planting. The experiment was laid out in RBD with five replications. The results obtained in the study have been summarised below : At the end of the third year Acacia auriculiformis had a DBH of 4.56 cm followed by Eucalyptus tereticornis with 3.82 cm and Casuarina equisetifolia with 1.62 cm. The mean annual diameter increments were 1.44 cm/year in Acacia, 1.20 cm/year in Eucalyptus and 0.51 cm/year in Casuarina. Acacia had more primary branches (27/tree) followed by Eucalyptus (23/tree) and Casuarina (17/tree). The first primary branch was 3.18 m above the ground in Eucalyptus, 2.22 m in Acacia and in 2.16 m in Casuarina. Acacia had 100% survival at the third year while Eucalyptus had 88%. But Casuarina had only 72% survival rates. In growth as well as survival, Acacia auriculiformis was found to be the best among the three. Eucalyptus tereticornis was found superior to Casusrina equisetifolia while the latter was the least impressive of the three. The total biomass yield at the third year was 98.438 mt (drymatter)/ha in Acacia auriculiformis, 48.424 mt/ha in Eucalyptus tereticornis and 12.506 mt/ha in Casuarina equisetifolia. Acacia had a mean annual biomass increment of 32.813 mt/ha. MAI of Eucalyptus was 16.141 mt/ha while that of Casuarina was only 4.169 mt/ha. In biomass production too, Acacia auriculiformis was found superior to Eucalyptus tereticornis and Casuarina equisetifolia. Of the three species Casuarina equisetifolia with a light intensity on the floor of 49.5% was the least shading one, followed by Eucalyptus tereticornis with 43.6% and Acacia auriculiformis with 30.6%. Eucalyptus was found to permit luxuriant undergrowth, so also casuarina. The above ground phytomass was 1.431 kg drymatter/m2 in Eucalyptus and 1,176 kg/m2 in Casuarina. But Acacia was found to inhibit undergrowth (0.183 kg/m2 ). Even the little undergrowth that was permitted by it comprised mostly of its own seedlings. The undergrowth in Eucalyptus comprised mostly of woody species (65.5%) while that of casuarina comprised mostly of grasses (68.5%). The presence of coal cinders had caused a rise in the soil pH, organic matter content, available Nitrogen content and available phosphorus content of the soil. The lowest pH value in the top soil was found in Acacia soil 4.31. Eucalyptus soil had 4.69 and Casuarina soil had 4.94 compared to the barren laterite (5.16) and the barren laterite with coal cinders (5.32). At the depth of 30-45 cm, the pH values were 4.85 in Acasia soil, 5.17 in Casuarina soil and 5.32 in Eucalptus soil. The barren laterite had a pH of 5.24 and in the barren laterite with coal cinders it was 5.42. The pH at 60-70 cm depth was 4.88 in Acacia soil 5.24 in Casuarina soil, 5.33 in Eucalyptus soil, 5.36 in barren laterite and 5.52 in barren laterite with coal cinders. All the three species reduced the pH of the soil. But Acacia auriculiformis was found to lower the pH of the soil more than the other two. pH increased with the depth in all the treatments. The organic carbon contents in the top soils were 0.57% in Acacia, 0.41% in Eucalyptus, 0.49% in Casuarina, 0.39% in barren laterite and 0.43% in barren laterite with coal cinders. The organic matter content was found to decrease as depth increased in all the treatments. There was a general rise in the organic carbon content of the soils due to the impact of the three species with the maximum in Acacia soils and the minimum in Casuarina soils. The available Nitrogen content in the top soil was 1277 kg/ha in Acacia, 1165 kg/ha in Eucalyptus, 1098 kg/ha in Casuarina, 874 kg/ha in barren laterite and 963 kg/ha in barren laterite with coal cinders. There was a reduction in the available Nitrogen content as the soil depth increased in all the treatments. All the three species caused an increase in the available Nitrogen content of the soil, the highest being observed in Acacia auriculiformis followed by Eucalyptus tereticornis. The available Potash content of the soils did not record any change under the different species. The available phosphorus contents of the top soils were 92.7 kg/ha in Casuarina, 90 kg/ha in Eucalyptus, 81.5 kg/ha in Acacia. 79.3 kg/ha in barren lateric and 87.4 kg/ha in the barren laterite with coal cinders. There was reduction in the content of the nutrient as depth increased in all the treatments. In Acacia soils the content of the available Phosphorus had decreased. Regarding the general observations, Acacia auriculiformis showed pronounced branching habits while Eucalyptus and Casuarina had more or less clean boles. Pests and diseases were not observed excepting the pink disease (c.o. Corticium salmonicolor) in Eucalyptus. Crows and rodents were the principal representatives of wild life in the plantion. Honey bees commonly foraged the inflorescence of Acacia. Acacia auriculiformis proved itself to be a highly promising tree for energy plantations and for afforesting sites dumped with coal cinders and for sites offering little protection from anthropogenic influences and grazing. It also improved the organic matter content and available nitrogen content of the soil and was free from graziers. But at the same time there were also unwelcome effects due to Acacia such as increasing the acidity of the soil and supressing undergrowth. It also tended to be highly branching. Eucalyptus tereticornis also was found to be good in growth and biomass production and could be recommended for similar sites. The species also enriched the soil by increasing the contents of organic carbon and available Nitrogen. Though it too reduced the pH of the soil, the species was found to support luxuriant undergrowth and was spared by graziers. Casuarina equisetifolia was a less suitable species for such a site as seen from the performance of the species. It suffered heavily from browsing and showed lesser survival growth and yield. But the species increased the organic carbon content and available Nitrogen content of the soil and permitted luxuriant undergrowth especially grasses.
Open Access
Social behaviour, dominance hierarchy and reproductive behaviour of sambar deer (cervus unicolor)
(College of Forestry,Vellanikkara, 1991) Krishnakumar, Kumar; R, KAU; Jacob Cheeran, V
A study was undertaken to investigate the social behaviour, dominance hierarchy and reproductive behaviour of sambar deer in captivity, mainly with the intention of evaluating the adaptability of the species to captive breeding. This study was conducted on the population of sambar deer in captivity at Trichur and Trivandrum zoos. Behavioural observations were made during a period spanning five months totally – from November – December 1988 to April – May 1989, on days at random. There were 21 deer in the herd at Trichur and 20 at Trivandrum. It was observed that the living conditions of the deer in these zoos are far from comparison to that of their natural habitats. Food, herd size, competition, nearest neighbour relationship etc: are strikingly different from nature. But, in spite of all adversities, the sambar deer have learned to adapt amazingly to changing conditions, and survive fairly well. The physiological processes of their lives, such as antler casting, rut, mating, gestation and delivery remain as scheduled, except for observations that births occur at any time of the year in captivity sometimes, which is in effect to the advantage of the captive -breeder ! Maintenance of ideal herd composition at any given time would help better the living conditions as well as curtail traumatic injuries and casualties. Paucity of adequate space is a serious constraint faced by these zoos. It is time that voluntary organisations and individuals came forward with earnest interest in the upkeep of zoos as in foreign countries ; rather than leaving the whole show in the sole hands of the government as the present practice. General awareness and overall change in the attitude of the public towards our vanishing wildlife is the need of the hour.
Open Access
Nutritional deficiency symptoms of ailanthus (ailanthuis triphyra (dennst.) alston)
(College of Forestry,Vellanikkara, 1993) Anoop EV; Gopikumar K
Sand culture experiments were carried out under controlled conditions inside a glasshouse attached to College of Horticulture, Kerala Agricultural University main campus, Vellanikkara, during the period 1991-93 for inducing deficiency symptoms of various nutrient elements in the seedlings of Ailanthus (Ailanthus triphysa (Dennst.) Alston). The effects of major nutrients viz., N, P, K Mg and S on the growth, chlorophyll content and nutrient concentration of seedlings in the nursery were also studied. The results were also confirmed by recovery studies by supplying the seedlings showing the symptoms of deficiency of various elements with complete nutrient solution. For the study, two months old seedlings of uniform growth were planted in containers filled with pure quartz sand and supplied with Hoagland No.2 (1948) nutrient solution. The treatment solution was prepared by eliminating the desired nutrient from the complete Hoagland nutrient solution. The characteristic deficiency symptoms produced by seedlings due to the deficiency of various nutrient elements include leaf discolouration, necrosis, scorching, defoliation and growth stunting. The seedlings showing visual deficiency symptoms were also photographed. Seedlings that received complete nutrient solution were healthy with dark green foliage. Vegetative growth of the seedlings was also found to be affected due to the nutrient stress. All the fractions of chlorophyll i.e., chlorophyll – A, chlorophyll – B and total chlorophyll of the treatment seedlings declined during the study period compared to control. Visual deficiency symptoms of the nutrient elements also coincided with a corresponding reduction in foliar levels of the concerned element. There was remarkable improvement in the growth and recovery of visual symptoms when the deficient element concerned was again supplied to the seedlings through complete nutrient solution.
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
Anatomy and utilization of two cane species of Kerala
(College of Forestry, Vellanikkara, 1988) Mohan, Varghese; KAU; Bhat, K M
Variation in certain anatomical and physical properties has been investigated and compared in two rattan species, viz. Calamus thwaitesii and C. travancoricus, the former representing the larger diameter and the latter possessing small-diameter canes of kerala. Five stems possing more or less similar number of internodes have been sampled in each of two species. There were significant differences between the two species in certain physical properties such as length and diameter of internode, stem “wood” density and initial moisture content although volumetric shrinkage did not differ appreciably. Similarly, quantitative data for anatomical properties such as corted percentage, number of vascular bundles per unit area, vascular bundle diameter, xylem and phloem percentage, metaxylem vessel element and fibre dimensions were markedly different between the two species while the fibre percentage had almost similar values. With the exceptions of internode size and fibre width, the mean physical and anatomical properties in each species showed definite patterns of longitudinal variation, which could be best explained using quadratic regression models. However, patterns of longitudinal variation were different between the species in volumetric shrinkage, number of vascular bundles per mm2, vascular bundle diameter, phloem percentage, metaxylem vessel element and fibre length. The most important useful features in distinguishing between the two species are internode length, stem diameter, epidermal cell and its lumen shape, diameter and frequency of vascular bundles as well as the diameter of wide metaxylem vessels. The most important determining factors of “wood” density are fibre percentage, fibre wall thickness and lumen width as well as the diameter of metaxylem vessels although features like the size and number of vascular bundles per unit area also influences this property. Volumetric shrinkage and moisture content are inversely related to the density of “wood”. With higher density owing to more thick walled fibres and narrower wide metaxylem vessels, basal portion of the stem is harder and heavier than top portion.
Open Access
Evaluation of provenances for seedling attributes in teak
(Department of Tree Physiology and Breeding, College of Forestry,Vellanikkara, 1996) Jayasankar, S; KAU; Luckins Babu, C
A randomized block design experiment involving the performance of selected provenances ie., Arienkavu, Konni, Malayattur, Nilambur, Parambikulam, Wynad and Thrissur (Local provenance) of Tectona grandis Linn. F. initiated during June, 1995 was used for the present investigation. The objective of the study included qualifying the seed characters, growth parameters, physiological and anatomical characters, root growth potential, field establishment and also elucidating the extent of nutrient uptake pattern, besides characterising the nutrient status dynamics. Seed characteristics like mean number of seeds per kg, 100 seed weight, purity percentage and individual seed parameters were found to vary significantly among the provenances tested. Parambikulam was found to be superior to other provenances, while local provenance recorded the least values for most of the parameters. Germination behaviour of teak provenances in the laboratory varied considerably among provenances. The overall performance was better in Konni which recorded a high germination percentage, peak value and MDG. Malayattur was showed to be inferior in these respects. Shoot, root growth, biomass allocation pattern, RGR and NAR were followed the trend that, Parambikulam, Nilambur and Malayattur consistently registered better growth rates in most of the stages of experimental period while, local provenance recorded the least values. Physiological parameters like LDR, transpiration rate, leaf water potential and RWC were influenced considerably among the provenances. Anatomical character like stomatal frequency was also varied among provenances throughout the period. Concentration of nutrient in the different plant parts and uptake pattern were found to be higher in Malayattur, Nilambur and Parambikulam especially with a high magnitude of N use efficiency. Local provenance registered a low accumulation of nutrients in different plant parts. Root growth potential studies showed significant variation among the provenances. Malayattur and Nilambur provenances had relatively higher values in RGP. While, Thrissur recorded a poor growth performance in this respect.
Open Access
Biomass production and resource partitioning in silvi-pastoral systems
(College of Forestry, Vellanikkara, 1993) Suman Jacob, George; KAU; Mohankumar, B
A randomized block design experiment involving factorial combinations of four fodder species : Pennisetum purpureum (hybrid napier), Brachiaria ruziziensis (congo signal), Panicum maximum (guinea grass) and Zea Mexicana (Teosinte) and four tree species (Leucaena leucocephala, Casuarina equisetifolia, Acacia auriculiformis and Ailanthus triphysa initiated in June 1988 was used for the present investigations. The study was pursued with the objective of quantifying the biomass production potential of selected forage species grown in association with tree components after canopy closure, comparing the productivity of different tree components grown in silvopastoral systems; characterizing the micro-site enrichment and nutrient cycling aspects of silvopastoral systems, analysis the partitioning of solar radiation among the different components of the system and elucidate influence regarding the nature of root interactions in silvopastoral systems. The tree attributes such as biomass, height, DBH and crown diameter were in the order acasia > leucaena>casuarinas>ailanthus and the fodder biomasses were in the order hybrid napier> guinea grass > congo signal>teosinte. The concentration of N,P and K in the above ground portion decreased in the order: leaves >Branches >bole. The N-fixing trees, in general, had lower nutrient – use efficiencies. Amount of photosynthetically active radiation interception by the tree canopy was a cardinal factor effecting the herbage yield a direct correspondence was lacking. All the three N-fixing species had markedly higher soil nitrogen status. Soil organic matter, K and P were also higher under the tree canopy. Recovery pattern of 32p isotope injected in the soil revealed that 65 to 85 percent of the fine roots responsible for water and nutrient absorption were concentrated in the 0-15 cms layer of the soil profile. However, 32P recovery from the tree monocultures was generally low suggesting stimulatory effect of nutrient absorption by trees in presence of an associated field crop. The rate of litterfall amount of detritus produced ranged from 1.92 Mg ha-1 yr-1 (ailanthus) to 6.2 Mg ha-1 yr-1 (acacia). Relatively lower contents of nitrogen and phosphorus in the litter recorded during the dry period (March-April). Regarding the inter – specific variations with regards to litter decomposition rates, casuarina and leucaena litter decomposed at a faster rate than acacia and leucaena. The nitrogen and phosphorous contents of the decomposing litter increased during the one – year decay period for all the species. Although widely accepted and yield initial N, lignin or initial lignin/nitrogen could not be directly related to decay rate coefficients in the present study.

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