Genda Singh , Sahadev Chouhan , T. R. Rathod

Abstract

Socio-economic and floral diversity survey in some selected villages of Bikaner area of Indian Desert was done in December 2001 with a view to assess the relationship between vegetation and socio-economic status and suggest management strategy in the area. The area had low floral diversity whereas agriculture and livestock rearing were the main resources of livelihood. Livestock to human population ratio was 1.5 with a total annual requirements of fodder and fuelwood were 0.11 lakhs tonnes and 3905.50 tonnes, respectively, though the people are also using animal dung at the rate of 1163.96 tonnes in these villages. This caused over-exploitation of existing vegetations, which are less both in number and abundance. P. cineraria and T. undulata are trees and Z. mauritiana is shrub of irrigated agricultural land. These species along with C. polygonoides, L. sindicus and C. jwarancusa are decreasing in the area as a result of their removal to cultivate cash crops like A. hypogea and R. communis in agriculture land and over-grazing/over-exploitation in forest lands and CARs. The removal and overexploitation of vegetations are resulting in land degradation and encroachment of more adaptable and less values species like P. juliflora, L. pyrotechnica, A. pseudotomentosa, C. burhia, D. sindicum and A. hyrsticula in the forest and CARs areas. Hence protection and conservation of natural vegetation are needed to enhance plant diversity and productivity in the area. The improvement in land status and productivity of common property resources through afforestation and resource management would influence the economy and the living standard of these desert dwellers without deteriorating land resources.

Keywords

Indian Desert, Vegetation Diversity, Socio-economic Profile

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G. Singh , T. R. Rathod , S. R. Baloch , Chandan Singh Purohit

Abstract

During study on vegetation diversity, 88 species of grasses and herbs were identified in 2005 and 2006 at Bara Nandara kho, Banswara (Rajasthan). Out of these, 14 species recorded as new arrival in the areas, when compared with the other existing literature of the region. These species are Brachiaria deflexa, Brachiaria setigera, Croton bonplandianum, Cyperus arenarius, Eragrostis aspera, Euphorbia granulata, Indigofera sessiliflora, Justicia prostrata, Justicia simplex, Ocimum canum, Rhynchosia bracteata, Sporobolus nervosus, Stylosanthes fruticosa and Triumfetta rhomboidea. Out of these B. deflexa, B. setigera and C. arenarius are species of xeric environment; whereas the other species are of semi-arid or dry sub-humid region. Such changes in vegetation composition resulted from invasion of other species are indicative of variations in climatic and edaphic conditions in the region.

Keywords

Banswara District, Rajasthan, Flora, Additions

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G. Singh , Bilas Singh , T. R. Rathod

Abstract

Arid regions have low capacity to sequester carbon due to low soil water availability and plant growth. However , considering the large extent of such areas total capacity of carbon sequestration may be important. One-year-old planted seedlings of E. camaldulensis , A. nilotica and D. sissoo were maintained at different water regimes by re-irrigating the seedlings at 36.2 mm (T₁) , 26.5mm (T₂) , 20.2mm (T₃) , 18.1mm (T₄) and live saving irrigation (T₅) When the soil water content decreased to 7.56% , 5.79% , 4.44% , 3.23% and drying of leaves (T₅) in the respective treatments. Carbon content both in dry biomass and soil increased with age of the seedlings , but it decreased with decreasing irrigation quantity. A negative carbon balance was observed in T₅ at 12 months age. At the age of 48 months , carbon content varied from 14.91 to 0.72 kg seedling^-1 in E. camaldulensis , 8.67 to 1.74 kg seedling^-1 in A. nilotica and 12.42 to 0.36 kg seedling^-1 in D. sissoo. Carbon density was high under A. nilotica and low under E. camaldulensis. The study suggests that severity of soil water stress affected carbon sequestration whereas , enhanced availability of soil water through irrigation increased carbon storage in biomass and soil. Therefore , there is scope to increase carbon sequestration in dry areas through rain water management and supplying additional irrigation during availability of water.

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G. Singh , N. Bala , V. Kuppusamy , T. R. Rathod

Abstract

Growth and productivity of Cassia angustifolia was studied during 1997 to 2000 in presence of adult neighbours namely Acacia tortilis , Prosopis juliflora and Calligonum polygonoides. The objectives were to find out suitable combination to control sand drift and to increase overall productivity of arid area. Seedlings of above species were planted in September 1996 , whereas the C. angustifol ,ia was sown in July 1997. Growth of woody perennials , growth , phenology , biomass productivity and ischolar_main study of C. angustifolia and soil water content were the recorded observations. C. angustifolia flowered twice in a year and remains green during peak summer of May and June and therefore would be beneficial in sand drift control. It had deep penetrating ischolar_mains to gather limiting resources in this unproductive land. Production of C. angustifolia was higher (P<0.05) with C. polygonoides as compared to P. juliflora and A. tortilis. Soil water content was higher under C. polygonoides than that under other two species and suggested to be due to spreading type of canopy. Fresh weight of stem + twigs and leaves of C. angustifolia ranged from 61.9% to 66.7% and 33.3% to 38.1% , respectively with total above ground biomass production of 3.70 to 7.35 tonnes ha^-l. There was no difference between biomass of summer and autumn harvesting , though the production decreased with age of the plants. The combination of C. polygonoides and C. angustifolia was best to increase production of this dry land with additional benefits of sand drift control.

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G. Singh , T. R. Rathod

Abstract

A field study was carried out with the aim to monitor the growth and performance of Azadirachta indica and Colophospermum mopane grown by direct seeding in rainfed condition. Half kg fruits of each species were directly broadcast in deep ploughed 300 m ² plots. Seed germination, survival, height, collar diameter, number of branches and leaves were recorded. Root length and biomass partitioning was recorded at 9 months of age. Soil water content was recorded to observe its relation with seedling performance. Germination percent of A. indica and C. mopane was 53.9 and 94.2 in July 2001 with respective population of 27500 and 30100 seedlings ha^-1 . Survival in July 2002 was 1.2 and 9.7%, respectively. Growth was significantly (P<0.05) high in C. mopane. At the age of 9 months, ischolar_main of C. mopane seedligns was more than two fold larger as compared to that of A. indica. Shoot and ischolar_main dry biomass produced by C. mopane was 5.4 and 6.6 fold higher than the respective biomass of A. indica seedlings. Biomass allocation was high in ischolar_mains in both species and it was at the expense of leaves in A. indica and stem in C. mopane. High survival in C. mopane seedlings was due to their deep ischolar_maining behaviour thereby extracting water from the deeper soil layers as compared to A. indica, the ischolar_mains of which confined in top 70 cm layer. Conclusively, C. mopane had greater adaptability to the dry areas and could easily be raised by direct seeding.

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G. Singh , T. R. Rathod

Abstract

Soil water depletion in forty-five months old plants of E. camaldulensis, A. nilotica and D. sissoo was monitored in non-weighing 3 type of lysimeters of 2m ×2m ×2 m (8m³ capacity). Soil water was allowed to deplete up to 7.56% and was maintained at field capacity of Soil Water Content (SWC) by re-irrigating the seedlings at 36.2 mm. Total depletion of soil water from the plantation of E. camalulensis was 4.75mm day^-1 m^-1 depth. The depletion from A. nilotica plot was 3.45 mm day^- and that of D. sissoo was 2.62 mm day^-1. This indicated 13, 9 and 7 irrigation in 99, 94 and 97 days in E. camaldulensis, A. nilotica and D. sissoo plots, respectively. Partitioning between transpiration and evaporation was 66% and 34% in E. camaldulensis plot, 54% and 46% in A. nilotica plot and 38 and 62% in D. sissoo plots. The depletion in soil water from bare soil was 7.0 lit day that contribute significant amount of water loss. A provision of simple surface mulching with locally available under-shrubs and grasses saved the loss of 0.15 mm day (1.5 tones water ha^-1day^-1).

Keywords

Biomass Production, Arid Environment, Soil Water Depletion, Eucalyptus camaldulensis, Acacia nilotica and Dalbergia sissoo

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G. Singh , T. R. Rathod , N. K. Limba , G. R. Choudhary , A. U. Khan

Abstract

Survival and growth of Jatropha curcas was examined in relation to slope gradient and rainwater harvesting treatments with a view to use this species in revegetation of degraded hilly area with its socio-economic benefits. Varying slopes were <20%, 10-20% and >20%, whereas rainwater harvesting treatments were control (CL), contour trench, (CT), Gardonie (G), Box trench (BT) and V-ditch (V). Soil water content (SWC) was greater (p < 0.05) <10% area and decrease in order <10% <>20%<10-20% slope areas. SWC was lowest in the CL plots, whereas it was highest in Gradonie plots in August. The increase in SWC over control was by 16% and 24% in August 2006 and 2007, respectively. SWC was highest in CT in June 2006 and in BT in June 2007, and the improvement in SWC resulted from rainwater harvesting was by 51% and 15% in the respective treatments influencing survival and growth of J. curcas. The lowest survival in >20% slope area indicated its susceptibility to water stress, further supported by the highest growth in BT plots with the highest soil water. Plants were tallest (p < 0.05) in <10% and smallest in >20% slope area. The plants growing along the contour trench were tallest (p < 0.05), whereas plants growing in the control plots were smallest (p < 0.05) suggesting the beneficial effects of water harvesting on the growth of J. curcas in degraded areas. Conclusively Jatropha curcascan be used to restore degraded hilly tract utilizing rainwater harvesting.

Keywords

Jatropha curcas, Survival and Growth, Rainwater Harvesting Treatment, Socio-economic Benefits

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