bluuebunny/crossref_metadata_2025_split huggingface dataset:
Breakdown of Ficus fistulosa (Moraceae) leaves in Hong Kong, with special reference to dynamics of elements and the effects of invertebrate consumers
Authors: Lam Paul K. S. , Dudgeon David 
Published: July 2009

ABSTRACTSeasonal variations in the breakdown and dynamics of chemical elements in Ficus fistulosa leaves in a mixed forest on Hong Kong Island were investigated between October 1982 and September 1983. Mean rate of leaf material weight loss from coarse-mesh (3 mm) bags was 1.82% day-1, about four times that inside fine-mesh (0.2 mm) bags (mean rate 0.44% day-1). Breakdown rates varied seasonally with maximum rates in spring or summer, and were significantly correlated with prevailing temperatures, the rainfall of the two previous months, and the soil moisture content of the previous month. Potassium and Mg were rapidly leached from leaf material throughout the year while the concentrations of C, N, P, Ca and Na remained relatively stable. In the absence of macrofauna (inside fine-mesh bags) decomposition rate constants (k) were positively correlated with the mean abundance of mites and Collembola, as well as with total invertebrate abundance. In the presence of macrofauna (inside coarse-mesh bags) decomposition rate constants were positively correlated with isopod and amphipod abundance. There was no significant correlation between breakdown rates of leaf material and mesofaunal abundance inside coarse-mesh bags. The importance of climate and invertebrates as rate determinants of Ficus decomposition is discussed.
The forests of Bhutan: a vital resource for the Himalayas?
Authors: Sargent Caroline , Sargent Orlando , Parsell Roger 
Published: July 2009

ABSTRACTLarge areas of the Himalayas have become severely deforested although little has been published about the extent of this problem in the closed Kingdom of Bhutan. A preliminary survey was undertaken during 1983. Without detailed information or accurate maps, LANDSAT 2 imagery was used to prepare a sampling stratification and to plot the distribution of defined vegetation types after sampling and analysis. Eleven forest noda are described in relation to their habitats, and area and timber volume estimates given. Deforestation pressures are discussed.
Regeneration following clearing in a Jamaican montane forest: results of a ten-year study
Authors: Sugden A. M. , Tanner E. V. J. , Kapos V. 
Published: July 2009

ABSTRACTSuccession was monitored over ten years in a 10×10m plot in forest with mor humus at 1550 m in the Blue Mountains of Jamaica, following the removal in January 1975 of all aerial plant parts and some of the root material. In April 1977, August–January 1980/1 and August 1984, all woody recruits in the plot were tagged and numbered, identified and measured (height), and mapped on a 1 m grid. The height of coppice was recorded. Ten of the eleven tree species present before felling produced coppice shoots. Two individuals almost attained canopy height by 1984. Twenty tree species and three shrub species were recruited from seed; six of the tree species were normally absent from the forest. Species composition changed very little with time.The rate of seedling recruitment was greatest immediately after clearing. The overall den-sity of individuals changed little after 1977. Overall mortality of recruits was about 10% per annum. Mortality of the earliest recruits declined with time since establishment. Later recruits and individuals with poor growth had higher mortality than other plants. Mortality was not density-dependent. Growth rates of recruits were relatively slow. Only ten individuals exceeded 4 m by 1984.Recruitment rates, density, growth and species diversity were greatest in the parts of the plot where the mor humus had been removed or piled up during the initial clearance. Recruit-ment, growth and density were least, and mortality was greatest, at the edge. There was no relationship between any of these parameters and the presence of coppicing stumps.Tree species showed a clear spectrum from obligate gap-demanders to obligate shade-bearers. The persistence of gap-demanding species in this forest (in which gaps are normally rare) may be due to infrequent hurricanes, and also to a natural ability to produce basal sprouts. The succession conforms to an initial floristic composition model; it is slow, and we suggest that at least 50 years will elapse before the plot begins to resemble the undisturbed forest.
Life cycle and diet of Zygonyx iris insignis (Insecta: Odonata: Anisoptera) in Hong Kong running waters
Authors: Dudgeon David , Wat Christina Y. M. 
Published: July 2009

ABSTRACTZygonix iris is widespread in tropical Asia, and larvae are sprawlers/clingers on rock surfaces in fast-flowing streams and rivers. In the Lam Tsuen River, Hong Kong, this species is univoltine; emergence occurs prior to the summer monsoon and larval recruitment during the wet season. Studies on larval dietary composition in four habitats indicated that Z. iris is a generalist predator, consuming epibenthic prey taxa in proportion to their abundance in the environment. Larval Chironomidae (Diptera) and Baetis (Ephemeroptera) were the commonest food items at all sites and there was little consistent evidence of preference for individual taxa. Larger Z. iris larvae tended to consume more prey taxa than did smaller larvae, and Baetis prey size was positively correlated with predator size. No size selection of chironomid larvae was apparent. Despite its unusual larval habit, Z. iris is a generalist feeder resembling lotic and lentic temperate-zone Odonata.
Changes in a secondary forest in southwestern Nigeria following a ground fire
Authors: Isichei Augustine O. , Ekeleme Friday , Jimoh Bakare A. 
Published: July 2009

ABSTRACTIn January 1983, two 50 m × 50 m rain forest plots in the University of Ife campus in southwestern Nigeria were demarcated for a baseline study of species composition, litterfall and tree girth increments. By accident, a severe ground fire burnt one of the plots on 31 January, barely two weeks after litter traps had been set and species listing and first girth measurements completed.The effect of this fire was assessed in the burnt plot after 14 months, in April 1984. The fire affected small trees especially, and there were indications that some species were more sensitive than others.Manihot glaziovii, which was present in the plot and abundant in its vicinity before the fire showed a big increase in density after the fire because it was able to germinate in the openings created by the fire. These observations were related to succession, and it is concluded that the observation by some workers that the initial composition of a regrowth forest may be partly predicted from a knowledge of the seed bank in the soil may be applicable in the present case.
Mosaic patterns in dipterocarp rain forest in Indonesia, and their implications for practical forestry
Authors: Torquebiau Emmanuel F. 
Published: July 2009

ABSTRACTTropical rain forest is described as a mosaic of ecologically uniform patches. A method is proposed to recognize and inventory the patches and to draw mosaic maps, based on the size and architecture of canopy trees. Mosaic maps from three different forest localities in Indonesia are compared in terms of the relative area occupied by each kind of patch, and the surface range and number of constituent patches. The comparison shows that the mosaic patterns are specific to the sites and can be used for the characterization of patch dynamics in different forest types. Possible implications for forest management are discussed in the light of the mosaic maps.
Ant foraging on ant-inhabited Triplaris (Polygonaceae) in western Brazil: a field experiment using live termite-baits
Authors: Oliveira Paulo S. , Oliveira-Filho Ary T. , Cintra Renato 
Published: July 2009

ABSTRACTForaging parameters of two ant species, Pseudomyrmex triplarinus and Crematogaster sp., on P. triplarinus-occupied shrubs of Triplaris surinamensis were evaluated in a semi-deciduous forest of Mato Grosso, western Brazil. Live workers of the termite Microcerotermes strunckii, used as baits for ants, were placed on leaves in the lower, medium and upper thirds of the crown of thirty experimental Triplaris (nine baits/plant). Besides attacking more than twice as many baits as Crematogaster (131 against 59), Pseudomyrmex also attacked them signifi cantly faster. Pseudomyrmex patrolled the plant uniformly, while Crematogaster patrolled more intensively the lower portion of the crown of Triplaris. Baits retrieved by Pseudomyrmex were taken to their nests in the stem galleries of Triplaris; those retrieved by Crematogaster were carried to nearby nests in the forest understory. Greater aggressiveness and alertness to foreign objects (i.e. baits), better eyesight, larger size, and an individual foraging technique appear to be responsible for the greater foraging success of Pseudomyrmex when compared with Crematogaster.
The dynamics of tree populations in tropical forest: a review
Authors: Swaine M. D. , Lieberman Diana , Putz F. E. 
Published: July 2009

ABSTRACTPublished work on the dynamics of forest tree recruitment, growth and mortality in natural tropical forest is reviewed. In most forests studied, annual mortality is between 1% and 2% and is independent of size class in trees >10 cm dbh; mortality is negatively correlated with growth rate and crown illumination; growth rate is highly variable between individual trees, but shows strong autocorrelation between successive measurements on the same tree.Differences in the rate of dynamic processes can be detected between some species at a site, but data are presently insufficient to determine whether these differences are preserved at other sites where the species occur. None of the studies discussed are of sufficient duration to permit us to draw any conclusions about the equilibrium or non-equilibrium of floristic composition.
Herpetofauna of a northern Australian monsoon rain forest: seasonal changes and relationships to adjacent habitats
Authors: Martin K. C. , Freeland W. J. 
Published: July 2009

ABSTRACTThe herpetofauna of a floodplain monsoon rain forest in northern Australia is composed primarily of species from non rain forest habitats. The majority of frog species use rain forest as a seasonal refuge, and there is a marked increase in numbers during the dry season. Faunal richness lies within limits expected on the basis of the length of the dry season and species richnesses of non-Australian faunas. There are few lizard species and an abundance of frog species (none of which is a rain forest specialist) in comparison to rain forest herpetofaunas in other tropical regions. The impoverished lizard fauna, and the paucity of rain forest specialists may be because (a) seasonal invasion of rain forest by frogs prevents evolution of, or colonization by, specialists or (b) rain forest specialists may not have been able to cross semiarid habitats separating the Northern Territory from eastern Australian rain forests. The herpetofaunas of monsoon forests in Cape York Peninsula may provide a means of distinguishing between these hypotheses.
The distribution and ecology of the freshwater prawnCaridina singhalensis(Decapoda, Atyidae) endemic to Sri Lanka
Authors: Benzie John A. H. , De Silva P. K. 
Published: July 2009

ABSTRACTThe distribution and microhabitat preference of the freshwater prawn,Caridina singhalensis, endemic to Sri Lanka, was determined. The species is now restricted to a 10–15 km stretch of the Behihul Oya headwaters, its distribution being determined by physiography and agricultural development.Beds ofIsolepis fluitanssupport some 76% of the adult population, at mean monthly densities of around 210 individuals m−2.Aponogeton jacobseniibeds and roots of marginal vegetation beneath overhanging banks support about 12% each, at mean monthly densities of 41 individuals m−2. The prawn produces young all year round but a peak in the number of ovigerous females occurs from September to January. Only juveniles produced after the rains appear to survive in great numbers. The submerged roots of marginal vegetation form a nursery area for about 45% of the annual output of young. Conservation plans for this endangered species need to take account of the particular importance ofI. fluitansand root habitats toC. singhalensis.
The use of tubificids for weeding and aquaculture in paddy fields in Japan
Authors: Kurihara Yasushi , Kikuchi Eisuke 
Published: July 2009

ABSTRACTTubificid worms that live in the paddy mud increase in numbers when an organic fertilizer is applied. They mix the soil by passing it through their gut as well as by their burrowing and respiratory movements, thereby checking the sprouting of paddy weeds. Tubificids inhabiting the pond's mud also serve as fish food. It is suggested that such a pond might be appropriate for aquaculture.This study considers a method to control paddy field ecosystems based on the above to produce rice and freshwater fish, with organic fertilizers but without the use of herbicides and insecticides.
Interactions between nectarivorous birds and the flowers ofAphelandra sinclairianain Panama
Authors: Fraga Rosendo M. 
Published: July 2009

ABSTRACTFlowers ofAphelandra sinclairianahave features of flowers pollinated by hermit humming-birds (long corollas) and of those pollinated by territorial humming-birds (dilute nectar, clustered distribution). Flowers in large clumps at the peak of the blooming season were pollinated by two territorial humming-birds, but at the end of the season or in isolated plants the main avian pollinator was the non-territorial hermitPhaethornis superciliosus. Visits by avian nectar thieves were more frequent at high flower densities. The reproductive output of inflorescences was similar at different levels of flower aggregation.Aphelandraflowers in large clumps could exchange pollen with extraterritorial plants because territorial humming-birds did not completely exclude pollinating hermits. The commonest nectar thief at high flower aggregations was the passerineVermivora peregrina, the second most common nectar thief was the hermitPhaethornis longuemareus.
The ecology of small mammals in Ogba Forest Reserve, Nigeria
Authors: Iyawe John Giobaguan 
Published: July 2009

ABSTRACTA total of 392 small mammals belonging to five species of small rodents and four species of shrews were caught. The small mammals and their percentage composition were Crocidura nigeriae (20.9%), Crocidura grandiceps (11.7%), Crocidura crossei (9.7%), Crocidura flavescens manni (20.4%), Mus musculoides (39.0%), Praomys tullbergi (11.5%), Lophuromys sikapusi (3.6%), Lemniscomys striatus (1.3%), and Arvicanthis niloticus (0.3%).There were monthly variations in the number of Mus musculoides and Crocidura nigeriae.In Mus musculoides breeding was at a maximum at the beginning and towards the end of the wet season and early dry season. In Crocidura nigeriae breeding was maximal during the wet season and low in the dry season.The seasonal changes in the age structure of the two most common species: Mus musculoides and Crocidura nigeriae, are described.
Analysis of the niche of two sympatric species of Bombus (Hymenoptera, Apidae) in southeastern Brazil
Authors: Camillo Evandro , Garófalo Carlos Alberto 
Published: July 2009

ABSTRACTThe sources of food and the width and overlap of the food niches of Bombus atratus and Bombus morio were determined by field observations and analysis of the pollen loads carried to the colonies by worker bees. The two species together utilized 50 flower species of which 26 were used by both. Solatium paniculatum (Solanaceae) and Psidium guajava (Myrtaceae) were the most frequently visited plants.The food niche width and niche evenness for both species were similar. The correlation between niche width and niche evenness was non-significant showing that evenness does not depend on niche width. In addition, there was no correlation between niche width and overlap, i.e. overlap varied independently of niche width. A high overlap of food sources utilized by the two species was observed in September, October and November. This may be explained in one of two ways: (a) if B. atratus and B. morio compete for resources, competition would be more intense during those three months; (b) the convergency of both species to the same plant species (Solatium paniculatum and Psidium guajava) would only result in more intensive competition if resources were limiting. However, at that period of the year resources are abundant, therefore although the values of overlap were high, competition need not have occurred.
Elevational zonation of mammals in the central Philippines
Authors: Heaney Lawrence R. , Heideman Paul D. , Rickart Eric A. , Utzurrum Ruth B. , Klompen J. S. H. 
Published: July 2009

ABSTRACTTrapping and netting of small mammals on a land-bridge island (Leyte) and on an oceanic island (Negros) revealed similar patterns of elevational change in abundance and species richness. Fruit bats (Pteropodidae) reached their greatest local densities in agricultural areas, and were least abundant in montane mossy forest. The fruit bats found to be common in agri-cultural areas are widespread in Southeast Asia: in contrast, species that were most common in forested areas are Philippine endemics. Fruit bat abundance was greater on the oceanic island than on the land-bridge island. Trappable small mammals (families Soricidae and Muridae) showed no change in species richness with increasing elevation, but did show a gradual increase in overall abundance. Even though the oceanic island was depauperate of non-volant mammal species, it had the higher abundance of non-volant mammal individuals; however, this may have been due primarily to differences associated with the elevation of sampling sites. Murid rodents at the higher elevations on Leyte tend to be those that are members of the old endemic group of Philippine murids, and those at lower elevations tend to be members of more recently arrived groups. Most non-volant small mammals at all elevations on the oceanic Negros, and in agri-cultural areas on Leyte, are non-native species.
Patterns of seed rain at the edge of a tropical Queensland rain forest
Authors: Willson Mary F. , Crome F. H. J. 
Published: July 2009

ABSTRACTBoth vertebrate- and wind-dispersed seeds moved farther from rain forest into old field than from old field into forest. Vertebrate-dispersed seeds from the rain forest moved farther into the field than wind-dispersed seeds, but seeds of both types moved similar distances from field into forest.Habitat structure affected seed deposition patterns in the field, where shrubs provided perches for flying vertebrates. Vertebrate-dispersed seed deposition was significantly greater, and deposition of plumed, wind-dispersed seeds was significantly less, under shrubs than in the open. Deposition of vertebrate-dispersed seeds under fruiting shrubs was significantly less than under non-fruiting shrubs.
Fire, growth and survivorship in a Neotropical savanna grass Andropogon semiberbis in Venezuela
Authors: Silva Juan F. , Castro Fernando 
Published: July 2009

ABSTRACTThis study was conducted in a woodland savanna in western Venezuela exclosed from grazing and burnt once a year towards the end of the dry season. Mean annual rainfall is 1500 mm, with a strong seasonality.Two cohorts of seedlings of Andropogon semiberbis were tagged and monitored for up to three years. Several variables such as survivorship, plant size, seedling density, fire damage and distance to the nearest adult were measured or estimated. Two burning experiments to measure survivorship before and after fire, and two seedling-growth experiments to assess competitive interference from adult plants of three grass species were performed.The highest mortality takes place during the dry season and is due to fire. This decreases as the plants get bigger due to increasing structural complexity of the clump by growth which gives added protection to the meristems. Other mortality factors such as desiccation, uprooting and shading seem to be important during the wet season, when mortality rate is relatively constant. Survivorship during the first year and after three years is strongly correlated to the size attained by the end of the first growing season.Seedling densities are rather low and do not seem to play any role in survivorship in this population. Adult interference with seedling growth decreases with distance and seems to be due to root competition, although there is a tendency toward increased foliage interference related to the canopy structure of adult plants.
Comparative ecological studies of Paspalum vaginatum and Paspalum orbiculare in Nigeria
Authors: Lakanmi Olusola O. , Okusanya Olubukanla T. 
Published: July 2009

ABSTRACTThe growth response of Paspalum vaginatum S.W. and P. orbiculare Forst to different environmental conditions and the interactions between the two species were deter-mined experimentally in order to find out some of those factors which may be responsible for the species distribution. There was no difference in response (as measured by growth) of P. vaginatum to any of the soils tested but this was not so for P. orbiculare. P. vaginatum grew signifi-cantly better in waterlogged soil than in either moist or dry soil, while the soil moisture condi-tions had no significant effect on the growth of P. orbiculare. Salinity in the range of 0-50% that of sea water had no significant effect on the growth of P. vaginatum, however higher salinity significantly suppressed the growth. In P. orbiculare, salinity above 10% caused a signi-ficant decrease in growth to the extent that the species did not survive at 100% sea water concentration. In competition, P. vaginatum was the stronger competitor in red earth, the soil from its natural habitat, under saline conditions and in waterlogged conditions. The results are discussed in relation to the natural habitats of the species and used to explain, in part, their distribution.
The abundance of native insects on the introduced weed Mimosa pigra in Northern Australia
Authors: Flanagan G. J. , Wilson C. G. , Gillett J. D. 
Published: July 2009

ABSTRACTA monospecific stand of the alien shrub Mimosa pigra (Mimosaceae) was examined weekly for 14 months from March 1984. A total of 44 phytophagous insect species were found on M. pigra. The five most abundant of these made up 74% of the total community. This insect community in general showed a distinct seasonal cycle of abundance with maximum numbers during the wet season. However, a few species had a completely different pattern.Two species, Mictis profana (Hemiptera: Coreidae) and Platymopsis humeralis (Coleoptera: Cerambycidae), were observed to cause substantial damage to M. pigra. When compared with the fauna of M. pigra from its native region, Central America, that of the Northern Territory is low in leaf and flower-feeding insects. It is suggested that these types of insects be sought as future biocontrol agents to complement those native insects causing damage and those biocontrol agents already released.