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1

Vertical stratification and its relation to foliage in tropical forest birds in Western Ghats [India]

100%
Jayson E. A., Mathew D. N.
Acta Ornithologica
|
2003
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tom 38
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nr 2
The study was carried out from May 1988 to April 1993 in two types of tropical forests: the tropical evergreen and moist deciduous. The vertical distribution of birds and foliage abundance was recorded by visual observation in seven height classes, using the line transect method. The vertical distribution of 94 bird species was recorded in evergreen forest, and of 90 in moist deciduous forest. Bird species richness and the numbers of birds were highest in the stratum from 1 to 5 m in both the evergreen forests (57 species) and the moist deciduous forests (68 species). The species richness indices of birds in the two types of forest did not display such a clear relationship. Foliage abundance was high up to a height of 30 m in the evergreen forests, whereas in moist deciduous forests, foliage was abundant only up to 20 m. A significant positive correlation was obtained between foliage abundance and species richness and also between the numbers of birds in both types of forests. Significant correlation was also obtained between foliage abundance and the species diversity indices in the two types of vegetation.
2

Quantifying phyllostomid bats at different taxonomic levels as ecological indicators in a disturbed tropical forest

86%
Castro-Luna A. A., Sosa V. J., Castillo-Campos G.
Acta Chiropterologica
|
2007
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tom 09
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nr 1
With the aim of quantitatively evaluating the usefulness of phyllostomid bats as ecological indicators, we compared intra-family levels and feeding guilds between tropical old-growth forest and patches of secondary vegetation growing where the land had been used for shifting agriculture. There were significant differences between vegetation types in bat species composition, with the frugivore guild most abundant in secondary vegetation and the animalivore guild most abundant in the old-growth forest. These results are congruent with the findings for other Neotropical zones and appear to be associated with the type of soil management that allows secondary vegetation to grow. Using the Indicator Value method, two subfamilies, five genera and five species were found to have a significant indicator value. However, these numbers only represent a small proportion of the five subfamilies, 20 genera and 28 species recorded, indicating that under the disturbance conditions that characterize the study area, phyllostomid bats were poor ecological indicators. Even so, some species and subfamilies are useful as disturbance detectors.
3

Interlocked grain as an ecological advantage in large emergents and canopy trees

86%
Kojs P., Wloch W., Rusin A., Rusin T.
Polish Journal of Natural Sciences. Supplement
|
2003
|
tom 01
4
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Content available

Reduction in organic matter fractions and structural stability following cultivation of tropical forests in Ethiopia and Nigeria

86%
Mbagwu J. S. C., Piccolo A.
International Agrophysics
|
2004
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tom 18
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nr 1
5

Nitrate reductase activity as an indicator of nitrate fixation and assimilation by tropical forest species on St.Thomas Island

86%
Krywult M., Klich M.
Fragmenta Floristica et Geobotanica
|
2000
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tom 45
|
nr 1-2
6

Bat diversity in tropical forest and agro-pastoral habitats within a protected area in the Philippines

72%
Sedlock J. L., Weyandt S. E., Cororan L., Damerow M., Hwa S.-H., Pauli B.
Acta Chiropterologica
|
2008
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tom 10
|
nr 2
Parks and other protected areas in tropical forests often include secondary forest, cropland, and pasture. Documentation of the impact of such anthropogenic disturbance is essential for effective management. We re-sampled bats within Mount Isarog Natural Park (MINP), a protected area in southeastern Luzon, Philippines, seventeen years after a survey in old- and second-growth forest and in agro-pastoral areas was conducted in 1988. By employing harp traps and a tunnel trap, in addition to mist nets as used in the earlier study, we aimed to document species previously undetected by mist netting alone. We documented 26 bat species, seven of which were captured exclusively in harp traps, and two that were only captured in a tunnel trap. This survey resulted in nine new records of bat species for MINP, bringing the total number to 30. We did not recapture four species documented in 1988, all of which were noted in that study as uncommon. Nineteen species were captured in agro-pastoral areas on the south slope, including two Hipposideros spp. not captured at the forested sites.
7

Effectiveness of Korean pine (Pinus koraiensis) seed dispersal by small rodents in fragmented and primary forests

72%
Yang Y., Yi X.
Polish Journal of Ecology
|
2011
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tom 59
|
nr 2
The effectiveness of dispersers on seeds of Korean pine (Pinus koraiensis Siebold et Zuccarini) was investigated in three fragmented stands and one primary stand. The proportion of Korean pine trees was less than 7% in the fragmented stands but more than 90% in primary stand. Five estimates related seed dispersal (proportion of removed seeds, scatter-hoarded seeds, cache dynamics, dispersal distance and microhabitat) were assessed to see the effect of forest fragmentation on the probability of seed dispersal of Korean pine seeds. Our results indicated fast seed harvest of Korean pine by small rodents at the seed stations and no difference among the four stands. Scatter-hoarding rodents were potentially important in promoting natural regeneration of Korean pine as revealed by high proportion of seed removal (up to 50%), short seed lifetime from the seed release locations and lower proportion of seeds remained on the ground surface. Although a proportion of seeds were scatter-hoarded in fragmented stands, no seedling successfully established due to heavy predation. Dispersal distances were strongly left-skewed in fragmented stands, indicating that fragmentation is likely to be disadvantageous for longer distance dispersal. The effective dispersal was suffered from a very heavy cost as accompanied by a great portion of seed predation and lower level of scatter-hoarded seeds. Failing to see seedling establishment in fragmented stands rather than in primary stand indicated that fragmentation and deforestation have negative effects on dispersal behavior and consequently seed destination. Artificial tree plantation and pinecone protection are highly recommended for Korean pine regeneration.
8

Seed germination requirements of Ficus virens (Moraceae) as adaptation to its hemi-epiphyte life form

72%
Ji M., Qin H., Chen H., Wen B.
Polish Journal of Ecology
|
2018
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tom 66
|
nr 1
Epiphytes and hemi-epiphytes are important floristic, structural and functional components of tropical rainforests. Their specific responses to light, temperature and water conditions during seed germination allow them to coexist with tropical forest trees. Here we investigated the effects of temperature, red to far-red light ratio (R:FR ratio) and water stress on seed germination of Ficus virens in tropical seasonal rainforest in Southwest China. We used incubators to create required temperature regimes, polyester filters to produce R:FR ratio gradients and mannitol solutions to simulate water stress. It was found that seed germination of F. virens was inhibited in the simulated understory conditions, i.e., at lower temperature (22/23°C), especially when combined with the R:FR ratio of 0.25, for which the germination percentage was less than 20%. In contrast, the seed germination percentages in the simulated canopy environment (22/32°C) showed no significant difference between R:FR ratios, with an average seed germination percentage as high as 65.8%. Seed germination delayed and decreased along with increasing water stress and was completely inhibited at -2.5 MPa, which might suggest that it is a kind of adaptation for F. virens seeds to detect the rainy season as germination chance on the canopy. Therefore, our study revealed the physiological mechanism for F. virensto be able to adapt to canopy environment.
9
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Content available

Estimating forest biomass by remote sensing RADAR data in Brazil

72%
Santos J. R., Gama F. F., da Conceicao Bispo P.
Drewno. Prace Naukowe. Doniesienia. Komunikaty
|
2014
|
tom 57
|
nr 192
10

Changes in the structure of avian community along a moisture gradient in an urbanized tropical riparian forest

72%
Kopij G.
Polish Journal of Ecology
|
2020
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tom 68
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nr 3
11

Density of tiger and leopard in a tropical deciduous forest of Mudumalai Tiger Reserve, southern India, as estimated using photographic capture-recapture sampling

72%
Kalle R., Ramesh T., Qureshi Q., Sankar K.
Acta Theriologica
|
2011
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tom 56
|
nr 4
Density of tiger Panthera tigris and leopard Panthera pardus was estimated using photographic capture–recapture sampling in a tropical deciduous forest of Mudumalai Tiger Reserve, southern India, from November 2008 to February 2009. A total of 2,000 camera trap nights for 100 days yielded 19 tigers and 29 leopards within an intensive sampling area of 107 km2. Population size of tiger from closed population estimator model Mb Zippin was 19 tigers (SE = ±0.9) and for leopards Mh Jackknife estimated 53 (SE = ±11) individuals. Spatially explicit maximum likelihood and Bayesian model estimates were 8.31 (SE = ±2.73) and 8.9 (SE = ±2.56) per 100 km2 for tigers and 13.17 (SE = ±3.15) and 13.01 (SE = ±2.31) per 100 km2 for leopards, respectively. Tiger density for MMDM models ranged from 6.07 (SE = ±1.74) to 9.72 (SE = ±2.94) per 100 km2 and leopard density ranged from 13.41 (SE = ±2.67) to 28.91 (SE = ±7.22) per 100 km2. Spatially explicit models were more appropriate as they handle information at capture locations in a more specific manner than some generalizations assumed in the classical approach. Results revealed high density of tiger and leopard in Mudumalai which is unusual for other high density tiger areas. The tiger population in Mudumalai is a part of the largest population at present in India and a source for the surrounding Reserved Forest.
12

Effects of environmental variation and spatial distance on the beta diversity of woody plant functional groups in a tropical forest

72%
Zhang Z., Zang R., Wang L., Wang G., Zhang J.
Polish Journal of Ecology
|
2012
|
tom 60
|
nr 3
Tropical forests are among the most complex ecosystems on Earth. The high alpha-diversity of tropical forests has been amply documented, however, beta diversity, equally important for us to understand the mechanism of biodiversity maintenance, has seldom been studied. The main current hypotheses about the origin of beta diversity are as follows: (1) species composition is uniform over large areas; (2) species composition fluctuates in a random, auto-correlated way emphasizing spatially limited dispersal; (3) species composition is related to environmental conditions. Testing these hypotheses is important to understand ecosystem function and to manage ecosystems effectively. In this study, we quantified the relative influence of environmental variation and spatial distance on the beta diversity of woody plant functional groups in a tropical forest of Hainan Island, China. Floristic and environmental data were collected from 135 grid-sample plots. We classified woody plant functional groups based on frequency, growth forms and successional status, respectively. To see whether environmental variation and spatial distance influence beta diversity, the simple and partial Mantel tests, in conjunction with linear and spline regression models were performed. The results showed that environmental heterogeneity and spatial distance were the primary determinants of pair-wise species composition differences between plots in the study area. Common, tree and climax species were more sensitive than the others to changes in environmental heterogeneity and spatial distance. Except for rare, pioneer and shrub species, the others had apparently negative relationship between spatial distance and similarity. The distance decay of similarity was determined by joint influences of spatial distance and spatially-structured environmental variables. Spatial distance had the clearest effect on beta diversity at distances <15 km and with the increase in spatial distance, beta diversity was gradually controlled by environmental heterogeneity. This study provides further support for neutral theory and environmental control hypothesis as opposed to uniformly distributed hypothesis.
13

Echolocation calls of the bats of Trinidad, West Indies: is guild membership reflected in echolocation signal design?

58%
Pio D. V., Clarke F. M., Mackie I., Racey P. A.
Acta Chiropterologica
|
2010
|
tom 12
|
nr 1
Time-expanded echolocation calls were recorded from 29 species of Neotropical bats in lowland moist tropical forest in Trinidad, West Indies with three aims: (1) to describe the echolocation calls of the members of a diverse Neotropical bat community, especially members of the family Phyllostomidae, whose calls are not well documented (2) to investigate whether multivariate analysis of calls allows species and foraging guilds to be identified and (3) to evaluate the use of bat detectors in surveying the phyllostomids of Neotropical forests. The calls of 12 species of the family Phyllostomidae are described here for the first time and a total of 29 species, belonging to five families (Emballonuridae, Mormoopidae, Phyllostomidae, Molossidae and Vespertilionidae) were recorded. Quadratic discriminant function analysis (DFA) was used to obtain classification rates for each one of 11 individual species and for six guilds (based on diet, foraging mode and habitat) comprising 26 species. Overall classification rates were low compared to similar studies conducted in the Palaeotropics. We suggest that this may be due to a combination of ecological plasticity for certain species and a loose relationship between echolocation call shape, fine-grained resource partitioning and resource acquisition in phyllostomids.
14

Succession of fungi associated with decomposition of leaf litter in tropical evergreen forest (North-Eastern Thailand)

58%
Purahong W., Lerstaveesin P., Ampornpan L.
Polish Journal of Ecology
|
2010
|
tom 58
|
nr 3
The richness and diversity of filamentous fungi associated with the decomposition of leaf litter of three tree species (Castanopsis accuminatissima, Styrax benzoides, and Dipterocarpus (grancilis) in evergreen tropical forest in the northeast of Thailand were studied at 6 and 12 months after leaf fall. A total of 125 taxa were identified through examining 4,362 isolates. These comprised 6 species of Zygomycetes, 19 species of Ascomycetes, 62 species of Deuteromycetes, and 38 taxa of unidentified sterile mycelium. Each decaying stage of leaf litter had a different composition of taxonomic groups. The average percent similarity between fungi assemblages of different species litter and of decomposition stage ranged between 37–44% and 6–13%, respectively. The majority of fungal taxa found had a low frequency of occurrence. Six month decaying leaves had the highest number (2,093) of fungal isolates but the fungal taxa number (35) was much lower than in freshly fallen leaves and equal to 12 month decaying leaves. The freshly fallen leaves gave the lowest number (1,103) of isolates but the number (69) of fungal taxa was much higher than that found in the 6 month and 12 month decaying leaves. The most dominant fungal taxon was Trichoderma koningii. The Shannon-Wiener diversity index showed that the initial diversity (H’) of fungal taxa from freshly fallen leaves was the highest and equals to 2.9, 2.8 and 3.0 in C. accuminatissima, S. benzoides, and D. (grancilis) respectively.
15
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Phytochemistry, nutritional composition, and pharmacological activities of Thaumatococcus daniellii (Benth): a review

58%
Fadahunsi O., Adegbola P. I., Olorunnisola S. O., Akinloye O. A.
BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
|
2021
|
tom 102
|
nr 1
16

The Amazon floodplain demonstration site: Sustainable timber production and management of Central Amazonian white-water floodplains

58%
Wittmann F., Schongart J., Queiroz H. L., Wittmann A. O., Conserva A. S., Piedade M. T. F., Kesselmeier J., Junk W. J.
International Journal of Ecohydrology and Hydrobiology
|
2009
|
tom 09
|
nr 1
Within the frame of the UNESCO Ecohydrology Program, the present Demonstration Project aims at the enrichment of degraded várzea forest patches with economically important timber species in the Mamirauá Sustainable Development Reserve (MSDR), western Brazilian Amazon. Enrichment plantations will reduce exploitation pressure in the natural environment and will contribute to the conservation of várzea forests and its ecological integrity by introducing alternative sources of income for the inhabitants. We present preliminary results from an interdisciplinary research, including data about the use and the net present values of timber trees in western Brazilian várzea; growth models and management criteria of the most exploited timber species; and germination experiments, which demonstrate that várzea timber species are easy to germinate, without requiring complicate treatments and expensive materials. These data allow for the initialization of timber species reproduction at larger scales, and provide the scientific basis to enrich degraded várzea forests with economically important timber species.
17

Food habits of ungulates in dry tropical forests of Gir Lion Sanctuary, Guarajat, India

58%
Khan J. A.
Acta Theriologica
|
1994
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tom 39
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nr 2
Food habits of chital Axis axis (Exrleben, 1777), sambar Ceruus unicolor (Kerr, 1792) and nilgai Boselaphus tragocamelus (Pallas, 1776) of Gir Lion Sanctuary were studied from January 1987 to December 1988. Data were collected on feeding animals by direct observations using scan and focai animal sampling methods. Results suggest that all three species are mixed feeders to varying degree and grass to browse ratio varied significantly in different seasons. Chitai utilised 38 species of shrubs, ten species of grasses and two species of climbers whereas sambar and nilgai utilised 29 and 19 species of shrubs, respectively. As a result of drought in 1987, chital utilised far greater proportion of browse (leaves and shoots) during 1988 compared to 1987, sambar diet mainly comprised of bark material of six plant species during winter and summer of 1988. All three species utilised different species of Acacia and Zizyphus in Gir but their utilisation differed significantly between different species thereby facilitating their co-existence.
18

First results on the feeding ecology of sympatric shrews (Insectivora: Soricidae) in the Tai National Park, Ivory Coast

58%
Churchfield S., Barriere P., Hutterer R., Colyn M.
Acta Theriologica
|
2004
|
tom 49
|
nr 1
The feeding ecology of a multi-species community of shrews inhabiting secondary forest and cacao-coffee plantations in the Tai National Park (Ivory Coast) was investigated. A total of 553 shrews were captured and 194 alimentary tracts were examined. Ten species were found, including Sylvisorex megalura and nine species of Crocidura, forming a series with respect to body size. New ecological data on these little known African species are presented. All species of shrews ate a wide diversity of arthropods, with Coleoptera, Araneae, Formicidae and Diplopoda making the largest dietary contributions. Lumbricidae were eaten by two species. C. obscurior had an exceptionally long intestine for its size but there was no evidence of dietary specialisation in this or other shrew species. All species investigated ate predominantly small prey and there was no correlation between size of prey items consumed and body mass of shrew species. There was little evidence of resource partitioning amongst the shrews, despite differences in body size.
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