This study analyses the effects of anthropogenic disturbance on plant diversity and community attributes of a sacred grove (montane subtropical forest) at Swer in the East Khasi Hills district of Meghalaya in northeast India. The undisturbed, moderately disturbed and highly disturbed stands were identified within the sacred grove on the basis of canopy cover, light interception and tree (cbh $ 15 cm) density. The undisturbed forest stand had .40% canopy cover, .50% light interception and a density of 2103 trees per hectare, whereas the highly disturbed stand had ,10% canopy cover, ,10% light interception and 852 trees per hectare. The moderately disturbed stand occupied the intermediate position with respect to these parameters. The study revealed that the mild disturbance favoured species richness, but with increased degree of disturbance, as was the case in the highly disturbed stand, the species richness markedly decreased. The number of families of angiosperms was highest (63) in the undisturbed stand, followed by the moderately (60) and highly disturbed (46) stands. The families Rubiaceae, Asteraceae and Poaceae were the dominant families in the sacred forest. Rubiaceae was represented by 11, 14 and 10 species in the undisturbed, moderately disturbed and highly disturbed stands, respectively, whilst the family Asteraceae had 16 species in the moderately disturbed stand and 14 species in the highly disturbed stand. The number of families represented by a single species was reduced significantly from 33 in the undisturbed stand to 23 in the moderately and 21 in the highly disturbed stand. The similarity index was maximum (71%) between the undisturbed and moderately disturbed stand and minimum (33%) between the undisturbed and highly disturbed stands. The Margalef index, Shannon diversity index and evenness index exhibited a similar trend, with highest values in the moderately disturbed stand. In contrast, the Simpson dominance index was highest in the highly disturbed stand. There was a sharp 21 2 21 decline in tree density and basal area from the undisturbed (2103 trees ha and 26.9 m ha ) to the 21 2 21 moderately disturbed (1268 trees ha and 18.6 m ha ) and finally to the highly disturbed (852 trees 21 2 21ha and 7.1 m ha ) stand. Density-girth curves depicted a successive reduction in number of trees in higher girth classes from the undisturbed to the moderately and highly disturbed stands. The log-normal dominance-distribution curve in the undisturbed and moderately disturbed stands indicated the complex and stable nature of the community. However, the short-hooked curve obtained for the highly disturbed stand denoted its simple and unstable nature.

Floristic composition, diversity, dominance and distribution pattern of species and tree population structure were studied in three stands of a sub-tropical wet hill broad-leaved forest of Meghalaya, India, along a disturbance gradient. Tree species diversity declined with increasing disturbance. Disturbed stands showed low equitability or high dominance and the undisturbed stand exhibited high equitability or low dominance. Contagious distribution among the tree species increased with increasing intensity of disturbance. Species showing regular distribution were restricted only to the undisturbed stand. Effect of disturbance on tree population structure was analysed using density-diameter curves. In the disturbed stands tree species showed reverse J-shaped and/or negative exponential curves, while those in the undisturbed stand exhibited sigmoid to bimodal mound shaped curves.

JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact support@jstor.org.. British Ecological Society is collaborating with JSTOR to digitize, preserve and extend access to Journal of Applied Ecology. Summary 1. The subtropical humid forest of Meghalaya, India, has been exposed to various kinds of cultural disturbance of varying magnitude during recent years. In order to analyse the effect of disturbance on natural regeneration of a few dominant and commercially important tree species, viz. Schima khasiana and the oaks Lithocarpus dealbatus and Quercus griffithii, a study on seed production, dispersal and germination was carried out in three stands, differing in degree of disturbance, during the years 1988-91. 2. Seed production in L. dealbatus and S. khasiana varied significantly between the three stands and increased with increasing disturbance. It increased with increase in d.b.h. of the trees in all three species. Heavy seeding occurred in different years in different species. 3. Lithocarpus and Quercus spp. produced heavier seeds in the disturbed stands than in the undisturbed stand. 4. The number of seeds dispersed from the trees decreased with distance from the parent tree. The dispersal distance for Lithocarpus and Quercus was greater in the disturbed stands than in the undisturbed stand. However, the dispersal distance in the forest was very low irrespective of degree of disturbance. 5. Seed predation decreased and germination increased with distance from the parent tree in all three stands, suggesting that distance-related seed predation was not influenced by disturbance. 6. In an experiment with four treatments the greatest germination of seeds was observed on the moss layer, irrespective of species and forest stand. The presence of litter inhibited germination of seeds to a great extent in all the species. Germination of Lithocarpus and Quercus was better in the undisturbed stand than in the disturbed stands, while that of Schima khasiana was better in the disturbed stands.7. An analysis of the fate of seed populations of the oak species revealed that loss of seeds caused through consumption by rodents and insects and transportation by various agents accounted for more than 98 % of the seeds, while fewer than 1% of them germinated. 8. The findings of the study are discussed in relation to their potential application in management of the disturbed subtropical forests.

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Wheat-soybean is one of the most dominant cropping systems on the Vertisols of central India. Cultivation of durum wheat in winter season (November to April) has a considerable potential due to congenial climate, while soybean in rainy season (June to October) has witnessed a phenomenal growth in the last two decades in the region. Beside including a legume (soybean) in sequence with a cereal crop (wheat), combined use of available organic sources along with chemical fertilizers may prove beneficial for long-term productivity and sustainability of the system. A long-term experiment was conducted during 1995-2000 on the fine-textured Vertisols at Indore, India to study the effect of combined use of farmyard manure (FYM), poultry manure, vermicompost and biofertilizers (Azotobacter+phosphate solubilizing bacteria) with 0.5 and 1.0 NPK (120 kg N+26.2 kg P+33.3 kg K ha −1 ) on wheat, and residual effect on following soybean. Grain yield of aestivum wheat in the initial 2 years and durum wheat in the later 3 years was significantly increased with 0.5 NPK+poultry manure at 2.5 t ha −1 or FYM at 10 t ha −1 compared with 0.5 NPK alone, and was on par with 1.0 NPK. However, the highest productivity was obtained when these organic sources were applied along with 1.0 NPK. Quality parameters of durum wheat viz protein content, hectolitre weight and sedimentation value showed improvement, and yellow berry content was significantly lower with combined use of NPK+organic sources compared with NPK alone and control. Soybean did not show much response to residual effect of nutrient management treatments applied to wheat. Wheat gave higher profit than soybean, particularly in the later years due to lower grain yields and market price of soybean. However, the superiority of FYM as well as poultry manure along with 1.0 NPK was evident on the overall profitability of the system. Various soil fertility parameters including chemical and biological properties showed conspicuous improvement over the initial status under the treatments of FYM and poultry manure. Sustainability yield index was maximum under 1.0 NPK, followed by 1.0 NPK+ poultry manure or FYM. It was concluded that application of available organic sources, particularly FYM and poultry manure along with full recommended dose of NPK fertilizers to wheat was essential for improving productivity, grain quality, profitability, soil health and sustainability of wheat-soybean system.