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We examined the effects of forest patch size on woody tree species richness and abundance in tropical montane evergreen forest patches of the Nilgiri region, south India. We sampled woody trees (≥ 1 cm dbh) from 21 forest patches in the upper Nilgiri hills (> 2000 m elevation) and recorded a total of 35,146 individuals of 61 species, 45 genera and 30 families. Species richness and abundance of sapling/shrubs (≥ 1 to < 10 cm dbh) increased significantly with increasing patch size, but the species richness and abundance of small, medium and larger trees (≥ 10 to < 30, ≥ 30 to < 60 and ≥ 60 cm dbh, respectively) did not. Overall, forest interior species richness and abundance increased significantly with increasing patch size but edge species richness did not. Species richness and abundance of shade-tolerant and shade-demanding tree species also increased with increasing patch size. The abundance of zoochory dispersed tree species was significantly related to increasing patch size, but those dispersed by autochory did not display any clear relationship between patch size and species richness or abundance. Our findings suggest that with increasing forest patch area, tree compositional patterns may be driven by species specific shade-tolerance adaptations and dispersal patterns. Differential responses in these traits by the plant community within the individual habitat zones of forest edge and interiors likely plays a major role in determining the inherent plant community and thus the subsequent ecological processes of forest patches, including their responses to increasing patch area. [ABSTRACT FROM AUTHOR]

The study provides descriptive information of the floristic composition, forest structure and effects of disturbance on forest structure of a mid-elevation (≥ 1800 ≤ 2100 m amsl) tropical montane evergreen forests (sholas) in the Nilgiri Mountains, southern India. Sampling plots of 10 × 100 m (1000 m2, 0.1 ha) were surveyed in ten different locations within a large patch, giving a total sample area of approximately 1 ha. All individual stems (≥ 1 cm dbh) of trees, shrubs and lianas from these plots were identified to species level and counted. A total of 3896 individuals (≥ 10 cm dbh) comprising 97 species, 79 genera and 45 families were included. On average there were a total of 1246 individual stems of at least 10 cm per hectare with a basal area 53.33 m2 ha-1. The species abundance distribution did not differ significantly from a log-normal distribution. According to the Importance value index (IVI), five species, namely Litsea glabrata, Lasianthus venulosus, Meliosma simplicifolia, Daphniphyllum neilgherrense and Neolitsea fischeri were dominant species in the community and influenced forest structure more than any other species present. Lauraceae, Rubiaceae, Euphorbiaceae, Myrtaceae and Symplocaceae were most dominant families according to the Family Importance Value index (FIV). Our results also suggest that disturbance influences tree species richness and density and liana density and basal area, in addition toforest structure and changes species composition. Moreover, the study shows that one-hectare floristic inventories of shola forests can provide a useful tool for assessing plant biodiversity, and provide useful information for effective conservation and management of nature reserves. [ABSTRACT FROM AUTHOR]

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Copyright of Tropical Ecology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Tropical Ecology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Tropical Ecology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Tropical Ecology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Tropical Ecology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Tropical Ecology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Tropical Ecology is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Female reproductive success (fruit and seed set) in Pavonia dasypetala (Malvaceae) was only weakly related to pollinator attentiveness (number of pollinator visits and number of pollen grains deposited on stigmas). This result has implications for field studies of pollination: observational measures of pollinator attentiveness do not necessarily provide an, accurate basis for inferring reproductive success. Further, these results indicate that, although pollination is essential for seed set in this species, reproduction is not limited by pollination. Many flowers that were visited numerous times by hummingbirds and that received pollen in excess of the number of ovules per flower failed to produce fruits. If pollen is limiting, it is pollen quality rather than quantity that is inadequate. Patterns of reproduction in this species were as predicted if resource availability limits seed set (Stephenson 1981): (1) among mature fruits there was an excess of fruits with full seed set (4 or 5 seeds) and (2) probability of fruit, set decreased over the reproductive season. However, resource availability was not the only determinant of seed set in this species: there was also variation among individuals that seems unrelated to either pollen or resource availability. Reproductive success thus appears to be determined by several factors and cannot be described as simply pollen or resource limited. [ABSTRACT FROM AUTHOR]

Two groups of neotropical mistletoes differ in fruit structure and consequently in the manner their seeds are deposited by avian frugivores. Birds defecate seeds of one group in clumps, but deposit seeds of the other group singly by regurgitation. A significant proportion of adult plants of both species were found growing alone, indicating a higher mortality with seed clumping. [ABSTRACT FROM AUTHOR]