A. Chandra , R. R. Kalita , N. N. Zhasa , H. Mishra , J. Singh

Abstract

A survey on demand and supply of fuel wood was conducted in the Titabor block of Jorhat District (Assam). Average family size was observed to be 5. Maximum respondent belongs to the OBC category. Agriculture is the main land use system in the region. Total extraction and consumption of fuel wood in the surveyed population is found to be 605.25 tonnes and 676.08 tonnes per year respectively. Per capita consumption was found to be 495 kg/year. Out of the total extraction , 77% comes from homestead , 14% from bamboostead and 9% from forest. About 96 percent of fuel wood is consumed in cooking. Total deficit in the area is found to be 10.47% while deficit excluding extraction bamboostead and forest is observed to be 30.99%. A total of 28 species are being exploited for fuel wood in the region. Family income , type of houses and caste are the major factors that govern the consumption of fuel wood in the area.

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R. R. Kalita , A. Chandra , H. Mishra , N. N. Zhasa

Abstract

A detailed survey on bamboo was conducted in the Majuli block of Jorhat District of Assam. Ten per cent of the total households were undertaken for the study. The average size of the family was found to be 5 and total population of the block was 1,35,378. About 68.75 % of the households had small landholding i.e. 1-2 ha. About 67.50 % of the families had kutcha types of house and remaining 32.50 % pucca types of houses. General category is the dominant caste in the area that counts 45.62 % of total population whereas SC population is least (1.88%). Mainly bamboo is used for construction and repair of house and fence, and also used as food (kharisa), firewood, etc. The total extraction and consumption of bamboo in Majuli is 84,747 and 48,736 tonnes per year. About 36,011 tonnes of bamboo is found surplus in the Majuli. The per capita extraction, consumption and surplus of bamboo is found to be 626, 360 and 266 kg per year respectively.

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P. Khanna , D. C. Karnatak , A. Chandra

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20 clones in line plantation and 10 clones in compact block plantation trials have been laid out in the farmers agricultural fields at Yamunanagar (Haryana) by planting the ETPs of poplar clones under the agroforestry extension programme of UNDP project. Early findings indicate that the clones S7C15, St-67, G-3. and G-48 are good for line plantation as well as compact block plantings where as row planting the clone S7C8 also has shown good results. Clones L-88 and L-89 also appear to h ave good potential for growth in row planting but need more care and maintenance as compared to other clones. The results also prove that timely planting and proper care of the plantation are sine qua non for successful agroforestry plantations based on poplars.

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D. C. Karnatak , A. Chandra

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No abstract

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A. Chandra , S. I. Ahmed

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The bark beetles are the serious polyphagous pests of forestry and agriculture throughout the temperate tropicil zones. The beetles and larvae of these insects tunnel into the bark, bast and other sapwood of many species of standing green trees as well as freshly felled or logs in storage. The taxonomic study of these well known pests has been handicapped by the paucity of material and scattered literature. The present paper deals with general classlfication, diagnostic characters of chief tribes and sub families of this group. Members of Scolytidea and Platypodidea are distinguished from the rest of Coleoptera in having a medlam gular suture with two pregular sutures which extend from the median posteri of tentorial pit towards the anterior articulations of mandibles. Out of a total number of over 6000 species recorded from all over the world about 400 species of these beetles have been recorded from Indian region. A large number of them is still to be discovered. A list comprising of about 160 species of Indian Scolytidae present in F.R.I. collections is appended for the benefit of readers.

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A. Chandra , S. R. D. Guha

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During outside storage the bamboos (D. strictus) were attacked by various wood destroying microorganisms. The studies showed that like other major constituents lignin also progressively decreased due to decay as the storage period increased. This type of simultaneous depletion of the major constituents in wood
bamboo is caused due to white rot type of fungal decay. The studies also showed that lignin macromolecule had chemically changed. The elemental analysis of the dioxane lignin isolated from fresh and stored (decayed) bamboo as well as the emperical formula for an average C₉ or phenylpropane unit indicates variation in the nature of two lignins. The decayed lignins were higher in oxygen,lower in hydrogen, methoxyl value and carbon contents than of the sound bamboo lignin. The alkaline nitrobenzene oxidation of the decayed bamboo lignins gave lower yields of the main product, viz vanillin, syriagaldehyde and p-hydroxy-benzalhyde. In addition the molar ratio of syringaldehyde to vanillins(S/V) also increased which suggest the preferential degradation of the guaicyl units of the lignin during decay. Ultra violet studies carried out on decayed bamboo lignins show greater absorptions at 260 nm and 300 nm indicating changes in the lignin macromolecule.

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S. R. D. Guha , A. Chandra , J. P. S. Bist

Abstract

Bamboo is generally stored in outside locations in wood based industries in our country. The storage period extends from a few weeks to about nine months. During this period the bamboo is attacked by various wood destroying organisms, it is believed that more than 20 per cent of it is destroyed during outdoor storage. Various chemical treatments have been suggested for controlling the decay in bamboo/wood during outdoor storage. The paper deals with the use of three cheap indigenous chemical preservatives for treatment of bamboo during outdoor storage for a period of twelve months. The economic feasibility of the treatment has also been discussed. The pentachlorophenate (Sodium Salt) was found to be most economical and effective.

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S. R. D. Guha , A. Chandra

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Bamboo is the main raw material used in the Pulp and Papar Industry in India. It is generally stored in onside locations for periods ranging from few weeks to a year. During storage it is estimated that about 20-25 percent of the raw material is deotroyed due to attack hy wood destroying organism in order to protect the bamboo from deterioration different preservations treatments were given to the baboo D. strietus which were stored for a peried of twelve months. Detailed chemical studies of the untreated and treated bamboos at the begianing and after storage periods of 4,8 and 12 momths were carried out. Mycological studies on the stored bamboos were also made during this period. The pulp yield and strength properties of the hand sheets prepared from stored bamboos Were also evaluated. The preservative treatment cut down the wood substance lossed by about 28-30 percent in a period of twelve months, while the pulp yietd losses were reduced by about 30 percent.

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A. Chandra , S. R. D. Guha

Abstract

Cellulose is a major constituent of wood and constitute approximately one half of the wood substance. It occurs in fibre walls both in crystalline and amorphous forms, and is always accompanied by other polysaccharides. The total polysaccharides being called holocellulose. During outside storage the bamboos were attacked by wood destroying fungi resultiag in the loss or both holocellulose and α-cellulose contents, and also a reduction in the degree of polymerization both in the preservative treated and in untrtated bamboos (controls). The loss of α-cellulose in pentachoro-phenate treated bamboo was about 24% after a 12 months storage period, while the untreated controls showed a loss of about 31% during the same period similarly the holocellulose content was also depleted more in the control bamboos than in the preservative treated bamboos. The degree of polymerization of both the α-cellulose and the holocelhlose decreased consideratory during the storage period in untreated bamboos. As the storage period increased the degree of polylnerizatinn of α-cellulose and bolocellulose decreased gradually indicating a possible random cleavage of the molecules by the cdorbohydrates secreted by the white rot and soft rot fungi which decayed the bamboo during their outside storage.

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