Out of the total land area of India, measuring 3,29 million ha. (mha), 150 m ha. is uncultivated and 90 mha. is categorized as wasteland. The broad subdivision of the wasteland 1S categorized as saline and alkaline, wind and water eroded land forming considerable part of wasteland.



1.2 The process of regeneration of vegetation in degraded and denuded land, representing virtual sand dunes providing an insight into regeneration pattern and biodiversity of the region.

1.3 Complete vegetation pattern of Rajasthan has been studied (1, 2, 3, 4) and succession using hydrocarbon yielding plants has been established at energy plantation demonstration project centre (EPDPC) (5).

1.4 Present investigations were undertaken with an object to study colonizing wasteland under protected and natural condition.



The annual photosynthetic production of biomass is about eight times the worlds total energy use. Indian arid zone covers an area of about 0.3 million sq.km. The state of Rajasthan has total land area of about 3,42,274 Km2 out of which about 96,100 km2 is arid and rest semi arid. 90 million ha of area in India is wasteland around 60 percent of it lies in semi arid region. National remote sensing agency (NRSA) has revealed that during the period 1972-1975 and 1980-82 there has been a loss of 9 million ha of tree cover i.e. an average of 1.3 million ha per year. Out of total forest cover of 64.2 million ha only 36.14 million ha is adequately covered. Thus the effective forest cover is limited to 10.88 percent of geographical area of the country (3,27 million ha). According to National Firewood study committee (1982) the total requirement of fuel wood is around 133 millino tonnes where as annual availability is only about 49 million tonnes per year. Plantation in 15-20 million ha is required to meet this shortage. Total non forest land in India is about 93.69 million ha most of it is uncultivable. Raising energy plantations in the wastelands can provide non-exhaustible non polluting and renewable source of Bio-energy. Biomass energy crops for wastelands were screened and improved. A model system has been developed for the semi arid and arid regions which can be used globally specially in developing countries.



Detailed investigations were carried out on the process of wasteland colonization utilizing the

i) hydrocarbon yielding plants, ii) high molecular weight hydrocarbon yielding plants, iii) non edible oil yielding plants, iv) short rotation fast growing energy plants.

(I) Hydrocarbon yielding plants included :

1. Euphorbia lathyris Linn.

2. Euphorbia tirucalli Linn.

3. Euphorbia antisyphilitica Zucc.

4. Euphorbia caducifolia Haines.

5. Euphorbia neeriifolia Linn

6. Pedilanthus tithymaloides Linn/

7. Calotropis procera (Ait.) R. Br.

8. Calotropis gigantea (Linn) R. Br.

(II) High molecular weight hydrocarbon yielding plants :

1. Parthenium argentatum Linn.

(III) Non edible oil yielding plants.

1. Jatropha curcas L

2. Simmondsia chinenesis (Link) Schneid.

(IV) Short rotation energy plants

1. Cassia siamea Lam.

2. Acacia tortitis (Forsk) Hayne



RESULTS

Investigations on several plant species have been ; carried out at our center including Euphorbia lathyris Euphorbia antisyphilitica; Pedilanthus tithymaloides; Calotropis procera; Euphorbia neeriifolia and E. caducifolia and Simmondsia chinensis.







2. MATERIAL AND METHODS:

2.6 Representative soil of the experimental area \ was analysed chemically. Table 1 (8).



3. RESULTS AND DISCUSSION:

3.1 The early colonizers :

Some of the early colonizers including small ephemerals include: Polygala erioptera DC.; Polycarpaea corymbosa (L.) Lamk. ; Gisekia phamacioides L ; Mollugo cerviana (L.) Ser. ; Side ovals Forsk. ; Corchorus tridens L. ; Triumfetta pentandra A. Rick. ; Indigofera essiliflora DC. ; I. linnaei Ali. These plant species have their value as initial colonizer and are not suitable as biomass resource because" their yield potential is very low. These early colonizers provide helpful association for any subsequent plant to come in the succession like Artemisia scoparia Waldst. ; Farsetia hamiltonii Royle. ; Tephrosia purpurea (L.) Pers ; Citrullus colocynthis (L.) Schrad.; Boerhavia diffuse L. and other herbs.

Among the shrub species which came in the next season Leptadenia pyrotechnica (Forsk.) Decene.; Calotropis procera (Ait.) RBr.; Side cordifolia L. ; Crotalaria burhia Buch. - Ham. ; Verbesina encelioides (Cav.) Benth.&Hook. and grass Saccharum munja L. were abundant. In the second year of growth the tree species became dominant and undergrowth diminished to some species.

The important tree species included Acacia torti/is (Forsk.) Hayne. ; Acacia nilotica (L.) Wind.ex. Del. ; Leucaena /eucocephala (Lam.) de WItt. ; Acacia senega/ (L.) Willd.; Prosopis chi/ensis Stuntz..

3.2 Initial association:

Initial plant formed association and appeared to benefit with each other. These association included Calotropis procera (Ait) RBr. with nitrogen fixing Crotalaria burhia Buch-Ham. Besides this at a later stage the nitrogen fixing Tephrosia purpurea (L.) Pers. was largely predominant with other plant like Verbesina encelioides (Cav.) Benth. & Hook. Artemisia scoparia, Waldst; Sericostoma pauciflorum stock; Sida corditolia L.; Crota/aria burhia Buch.-Ham.; Boerhavia diffuse L. The biomass productivity ranged from 0.5 tonnes per ha. (Citrullus colocynthis), to 52 tonnes dry matter per he. per annum (Saccharum munja). A combination of these plant could be used to form a three tier system to colonize the wasteland and get productive biomass as an alternative model to the hydrocarbon yielding plants (6).



3.3 Some other association:

Boemavia diffuse, Citrullus colocynthis, Artemisia scoparia largely cover the ground throughout the year due. to their xerophytic adaptation make good association with these plants R. purpurea, V. encelioides, S. pauciflorum, C. bilmia, C. bonplandium, S. cordifolia, H. marifolium, P. angustifolia, P. corymbosa, E. hirta.





Anita Kumari and Ashwani Kumar

Some potential biofuel plants for semi-arid and arid regions and improving their growth and productivity. In: Sjunnesson, L., Carrasco, J.E., Helm, P., A. Grassi (eds.) Biomass for energy, Industry and climate protection. Pp 279-281. ETA-Renewable energies, Florence, Italy, WIP- Munich.



142 Kumar, Ashwani and Vijay R. Kumar. 2002. Bioenergy potential of semi-arid regions of

Rajasthan. In : Palz, W. , J.Spitzer, K.Maniatis, K.Kwant, P.Helm, A.Grassi.( eds)

12th European Biomass conference : Biomass for energy , Industry and climatic protection.

WIP Munich. Germany.



143 Kumar, Vijay Rani, Ashwani Kumar and A,K,Gupta. 2002. Calotropis procera: A potential bio-energy plant for arid and semi-arid regions. In : Palz, W. , J.Spitzer, K.Maniatis, K.Kwant, P.Helm, A.Grassi.( eds) 12th European Biomass conference : Biomass for energy , Industry and climatic protection.WIP Munich. Germany.















150 Kumar, A. and Vijay N. (2004) Studies on Laticifer Development in Calotropis procera an Important Plant Yielding Hydrocarbon and Improvement of its Growth Potential In : Van Swaaij, Fjallstrom, Helm and Grassi (eds):. Biomass for energy, industry, and climate protection. Proceedings of the Second World Conference ETA-Florence, Rome Italy WIP-Munich , Germany pp 176





151. Kumar, A. and Kotiya, A. (2004)

Some Potential Plants for Bio-energy In : Van Swaaij, Fjallstrom, Helm and Grassi (eds):. Biomass for energy, industry, and climate protection. Proceedings of the Second World Conference ETA-Florence, Rome Italy WIP-Munich , Germany pp 180





152. Kumar A. and S. Roy (2004)

Jatropha Curcas: A Potential Plant for Bio-Fuel In : Van Swaaij, Fjallstrom, Helm and Grassi (eds):. Biomass for energy, industry, and climate protection. Proceedings of the Second World Conference ETA-Florence, Rome Italy WIP-Munich , Germany pp 331





153. Kumar, A. Kumar, V.R. Parveen, S.. Shekhawat, V.P, Kotiya A. (2004)

Production and Improvement of Hydrocarbons in Laticifer Plants In : Van Swaaij, Fjallstrom, Helm and Grassi (eds):. Biomass for energy, industry, and climate protection. Proceedings of the Second World Conference ETA-Florence, Rome Italy WIP-Munich , Germany pp 346



154.Kumar, A., Singh, A. V.P. Shekhawat (2004)

Effect of Location on the Growth and Hydrocarbon Yield of Calotropis procera: A Case Study In : Van Swaaij, Fjallstrom, Helm and Grassi (eds):. Biomass for energy, industry, and climate protection. Proceedings of the Second World Conference ETA-Florence, Rome Italy WIP-Munich , Germany pp 350





155. A. Kumar, S. Sharma (2004)

Improving Growth and Productivity of Euphorbia Antisyphilitica; a Potential Bio-Fuel Plant from Semi-Arid Regions In : Van Swaaij, Fjallstrom, Helm and Grassi (eds):. Biomass for energy, industry, and climate protection. Proceedings of the Second World Conference ETA-Florence, Rome Italy WIP-Munich , Germany pp 353



156. Sharma . S, A. Kumar (2004) Studies on Biomass Utilization in the Rural India and Its Impact Assessment on Environment with Suggestions for Possible Alternatives In : Van Swaaij, Fjallstrom, Helm and Grassi (eds):. Biomass for energy, industry, and climate protection. Proceedings of the Second World Conference ETA-Florence, Rome Italy WIP-Munich , Germany pp 2508





157. A. Kumar, S. Sharma (2004)

Rural Energy Needs of India and Role of Women in Developing Alternative Sources of Energy: A Case Study In : Van Swaaij, Fjallstrom, Helm and Grassi (eds):. Biomass for energy, industry, and climate protection. Proceedings of the Second World Conference ETA-Florence, Rome Italy WIP-Munich , Germany pp 2510



158. Kumar, A., N. Vijay (2004)

Problems and Prospects of Biofuel Production in India In : Van Swaaij, Fjallstrom, Helm and Grassi (eds):. Biomass for energy, industry, and climate protection. Proceedings of the Second World Conference ETA-Florence, Rome Italy WIP-Munich , Germany pp 2526





159. Kumar, A. A. Tewari (2004) Improving the Biofuel Utilization Efficiency in the Rural Villages by Modifying the Fire Stove ‘Chulha’ In : Van Swaaij, Fjallstrom, Helm and Grassi (eds):. Biomass for energy, industry, and climate protection. Proceedings of the Second World Conference ETA-Florence and WIP-Munich Pp 2544



160. Anita Kumari and Ashwani Kumar

Some potential biofuel plants for semi-arid and arid regions and improving their growth and productivity. In: Sjunnesson, L., Carrasco, J.E., Helm, P., A. Grassi (eds.) Biomass for energy, Industry and climate protection. Pp 279-281. ETA-Renewable energies, Florence, Italy, WIP- Munich.







161. Anita Kumari, Ashwani Kumar, V.R. Kumar

Productivity of Calotropis procera in semia-arid regions of Rajasthan and its use as renewable source of energy. In: Sjunnesson, L., Carrasco, J.E., Helm, P., A. Grassi (eds.) Biomass for energy, Industry and climate protection. Pp 276-278. ETA-Renewable energies, Florence, Italy, WIP- Munich.



162. Anupam Tewari* and Ashwani Kumar

Improving biomass use efficiency for semi-arid regions.

In: Sjunnesson, L., Carrasco, J.E., Helm, P., A. Grassi (eds.) Biomass for energy, Industry and climate protection. Pp 2187-2190 ETA-Renewable energies, Florence, Italy, WIP- Munich.