bluuebunny/crossref_metadata_2025_split huggingface dataset:
Standing biomass and carbon distribution in a papyrus (Cyperus papyrus L.) swamp on Lake Naivasha, Kenya
Authors: Jones Michael B. , Muthuri Francis M. 
Published: July 2009

ABSTRACTThe standing live biomass of papyrus swamps is high compared with most other communities dominated by herbaceous vegetation. For the first time, measurements of below-ground rhizome and root biomass are reported here, in addition to measurements of shoot biomass, for a papyrus swamp located on Lake Naivasha, Kenya. The ratio of rhizome and root to shoot dry weight was 1.38: 1 and the total standing live biomass was 7.8 kg(dry weight) m−2. Detritus, formed from slowly decomposing papyrus, is normally the most important sink for carbon in this ecosystem. The amount of detritus retained by swamps varies but at L. Naivasha it contained almost 20 times the carbon found in living biomass. The net primary production of the swamp was calculated to be 6.28 kg(dry weight) m−2 y−1, which is amongst the highest recorded productivities for natural ecosystems. Model estimates of carbon input into the system from photosynthesis are incorporated into a carbon flow diagram for the swamp and this emphasises the importance of detritus as a sink for carbon in this ecosystem.
Chemistry of bulk precipitation in southwestern Viti Levu, Fiji
Authors: Waterloo M. J. , Schelleken J. , Bruijnzeel L. A. , Vugts H. F. , Assenberg P. N. , Rawaqa T. T. 
Published: July 2009

ABSTRACTThe amounts and chemical composition of bulk precipitation were investigated over a continuous 21-mo period (January 1990 to September 1991) at four sites along an East-West transect perpendicular to the coast of Southwest Viti Levu, Fiji. Measured rainfall totals in 1990 ranged from 1796 mm at the coastal Korokula station to 2113 mm at the inland Tulasewa station, which is somewhat higher than the long-term average of 1707 mm at a reference weather station located in the centre of the study area. The first 9 mo of 1991 were relatively dry (range 1027–1533 mm) with a total of 1157 mm at the reference site as compared to a long-term average of 1330 mm. Concentrations of all investigated constituents in bulk rainfall were low, except during the passage of cyclone Sina due to the deposition of large amounts of, especially, chloride, sodium and sulphate in sea spray. Concentrations of sodium and magnesium could be explained fully by maritime contributions to the rainfall composition at all sites. Maritime contributions to the concentrations of calcium, sulphate and potassium accounted for 10–40% of the total, whereas bicarbonate, ammonium, nitrate, silicon, aluminium, iron and manganese were derived exclusively from terrestrial sources. The annual atmospheric nutrient deposition rates were low by pan-tropical standards, particularly when the contribution of cyclone Sina was excluded. Annual totals (in kg ha−1) ranged from 2.4–8.8 for nitrogen, 0.4–1.1 for phosphorus, 2.3–4.9 for potassium, 1.4–1.9 for calcium and from 1.1–1.3 for magnesium. The inclusion of the contribution by the cyclone more than doubled the deposition of potassium, calcium and magnesium, although values still remained well within the range reported for humid tropical areas. The estimated atmospheric deposition of nutrients over a typical rotation period (16 y) was sufficient to balance losses in harvestedPinus caribaealogs (stemwood plus bark) of potassium, calcium and magnesium, but not of nitrogen and, probably, phosphorus. Nutrient losses associated with the harvesting of stemwood alone were compensated entirely by the atmospheric inputs.
Flowering phenology and flower predation of Cullenia exarillata (Bombacaceae) by arboreal vertebrates in Western Ghats, India
Authors: Ganesh T. , Davidar Priya 
Published: July 2009

ABSTRACTThe flowering phenology and flower predation of Cullenia exarillata, a canopy tree at Kakachi in the southern Western Ghats, India, was studied from 1991 to 1993 in relation to general phenological patterns at the community level. Flowering was monitored from 30 marked trees and flower predation estimated from fallen flowers in 40, 1 m2 nets placed under the trees. Flowering occurs in the dry season and coincides with the period of fruit scarcity in the forest. Flowering is synchronous in the population and each tree produces a mean of c. 8730 flowers per tree over a period of c. 47 d. Flowers produced little nectar but the edible fleshy sepals compensated for this. Six species of arboreal mammals and seven species of birds ate the flowers. These consumed 57% of the flower crop of which 37% were completely destroyed. Flower predators could be important in flower fertilization. The overabundance of the flower crop and the timing of flowering, may have evolved as a strategy to satiate predators and enable the flowers to be pollinated during the annual period of fruit scarcity in the forest. This in turn makes Cullenia exarillata a possible keystone species in this forest.
Pre-dispersal and early post-dispersal demography, and reproductive litter production, in the tropical treeDicymbe altsoniiin Guyana
Authors: Zagt Roderick J. 
Published: July 2009

ABSTRACTThe demographic history of a flower-cohort of the tropical treeDicymbe altsonii(Caesalpiniaceae) was studied by collecting litter from flowers, fruits and seeds, and by monitoring seedling survival. Flower production was estimated at 137 to 172 m−2in a plot of 1 ha. Four percent of the flowers yielded a pod, which contained an average of 2.0 seeds. Post-dispersal mortality over 3 mo was 39% of the initial number of dispersed seeds. Most flowers and fruits were aborted. Insect and vertebrate predation in the tree and on the ground was very low. Reproductive litter production of this species was estimated to be equal to leaf litter production. The amount of phosphorus lost in litter from fruits and flowers was much larger than in leaf litter. This implies that the impact of the biennial flowering events on the nutrient dynamics of the trees and of the ecosystem may be large. It is argued that the reproductive cycle and the pre-dispersal demography ofDicymbeseem to be determined by a scarcity of nutrient resources, and possibly by pollinator limitation.
Impact of Hurricane Iniki on native Hawaiian Acacia koa forests: damage and two-year recovery
Authors: Harrington Robin A. , Fownes James H. , Scowcroft Paul G. , Vann Cheryl S. 
Published: July 2009

ABSTRACTDamage to Hawaiian Acacia koa forest by Hurricane Iniki was assessed by comparison with our previous measures of stand structure and leaf area index (LAI) at sites along a precipitation/elevation gradient on western Kauai. Reductions in LAI ranged from 29 to 80% and were correlated with pre-hurricane LAI and canopy height. The canopy damage resulted in a large pulse of litter, ranging from 4 to 19 t ha-1 across our study sites. In the first year post-hurricane, LAI recovery and relative increase in stand basal area were negatively correlated with the fraction of canopy LAI lost. The two major overstorey species, A. koa and Metrosiderous polymorpha, were damaged less than the sub-canopy species, Dodonaea viscosa and Psidium guajava. Although D. viscosa and P. guajava were both severely damaged in the hurricane, the alien species P. guajava had much higher survival than the native D. viscosa, both as adults and as seedlings. However, seedling density of P. guajava was limited by low recruitment. At these sites, there was no drastic change in species composition following hurricane disturbance, and forest structure and productivity had recovered to a great degree within 2 y.
Seed dispersal and predation in two populations ofCabralea canjerana(Meliaceae) in the Atlantic Forest of southeastern Brazil
Authors: Pizo Marco Aurélio 
Published: July 2009

ABSTRACTThe seed dispersal system of a neotropical tree,Cabralea canjerana(Meliaceae), was studied in two forested areas in southeastern Brazil. The first study site, Parque Estadual Intervales (PEI), is a 49,000-ha reserve composed mostly of old-growth Atlantic rain forest. The second site, Mata de Santa Genebra (MSG), is a 250-ha fragment of old-secondary semideciduous forest whose present bird fauna differs markedly from the original, in part as a consequence of forest fragmentation. At PEI 35 bird species ate the diaspores ofC. canjerana. Black-tailed tityra (Tityra cayana, Tyrannidae) was the main seed disperser, but several other species were also important seed dispersers. In contrast, at MSGC. canjeranadiaspores were eaten by 14 bird species. At this area, the red-eyed vireo (Vireo olivaceus, Vireonidae) was the most important seed disperser, but it was also a ‘waster’ which dropped seeds beneath parent plants, or carried them to sites unsuitable for germination. At PEI, exposed seeds on the forest floor were heavily preyed upon by rodents and insects. Insects destroyed mainly seeds deposited near to parent plants. Insect predation was less intense at MSG than at PEI. The rodent density at MSG was unusually small, and part of the post-dispersal seed predation may be done by terrestrial birds, such as doves and tinamous, which are especially common at MSG. Some of the differences recorded between the seed dispersal systems ofC. canjeranaat PEI and MSG may have been the result of the fragmentation and isolation of the latter area.
A test of the Janzen-Connell model with two common tree species in Amazonian forest
Authors: Cintra Renato 
Published: July 2009

ABSTRACTField experiments and survival analysis were used to test whether the Janzen-Connell model operated for two common Amazonian tree species in Peru: the midstorey palm,Astrocaryum murumuru, and the canopy-emergent legume,Dipteryx micrantha. Seed and seedling survival patterns of these species partially supported the model, depending on tree species, type of predator, spatial scale and the particular year. At a small scale of a 2.5-ha plot,Astrocaryumseed predation by insects and mammals was density-dependent. At a larger scale of 100 ha,Dipteryxseed survival increased with distance from conspecific adults, but forAstrocaryumseeds there was no distance dependence. At the scale of 200–400 haDipteryxseed survival was negatively related to the number of individuals present in groups of conspecific adult trees. In 1992 a higher proportion ofAstrocaryumseedlings survived far from, compared with close to, conspecific adult trees, whilst in 1993 moreDipteryxseedlings survived beneath conspecific adult trees than farther away.
Soil seed bank community dynamics in seasonally moist lowland tropical forest, Panama
Authors: Dalling J. W. , Swaine M. D. , Garwood Nancy C. 
Published: July 2009

ABSTRACTSeasonal changes in the densities of dormant seeds in the soil around eight pioneer trees in the 50-ha Forest Dynamics Plot, on Barro Colorado Island, Panamá were studied, and how seed dispersal and seed dormancy influenced patterns of seed abundance and distribution were examined. Twenty-four, 3-cm-deep soil samples were collected on 30 m transects radiating out from each of the trees in each of four time-intervals through the year, and four 21-cm-deep samples were collected beneath the focal tree crowns. In the surface 0–3 cm of soil, germinable seed densities of all species combined declined from a peak of 1090 seeds m−2in the mid-wet season in August, to 330 seeds m−2by the end of the wet season in November. In contrast, at soil depths >3 cm, there was little variation in soil seed bank density through the year. Some variation in soil seed bank density for individual species could be accounted for by distance to reproductive conspecifics. Among species, abundance in the soil was negatively correlated with seed size. Seed persistence varied greatly among species at this site; after 1 y of burial in mesh bags, seed germinability of four species was near zero, while four other species showed no consistent decline in seed germinability after >2 y of burial. For at least one species,Trema micrantha, prolonged seed dormancy was also possible under natural conditions. Twenty-five percent ofTremaseeds extracted from the soil at a site occupied by an isolatedTrematree that died between 1982 and 1985 were still germinable in 1994.
Annual foraging of the leaf-cutting antAtta colombicain a semideciduous rain forest in Panama
Authors: Wirth Rainer , Beyschlag Wolfram , Ryel Ronald J. , Hölldobler Bert 
Published: July 2009

ABSTRACTIn a 1-y study of vegetation harvested by the leaf-cutting ants,Atta colombicaGuérin, daily harvesting activity of two nests was observed for 24 h atc.1-wk intervals (colony I: June 1993-June 1994; colony II: February-June 1994) on Barro Colorado Island. The average daily quantity of green leaves harvested by colony I was higher during the wet season (11.4 m2d−1) than during the dry season (9.0 m2d−1), but was highly variable between survey days. Total annual herbivory of green leaves was estimated to be 3,855 m2foliage area for colony I and 1,707 m2for colony II. Total dry weight of biomass harvested was higher in the dry season because most material collected during the wet season consisted of green leaves, while during the dry season, more than 50% of the total collected biomass was non-green plant material (stipules ofFicussp., fruits, seeds, and flower parts of a variety of other species) which representedc.one third (111 kg y−1) of the total annual intake (370 kg y−1) of plant material. Total daily biomass intake was negatively correlated with daytime rainfall. The peak of daily foraging was affected by timing and duration of rainfall events. Highest input rates normally occurred between 15:00 and 16:00 h (colony I).Dry weight and surface area of harvested leaf fragments differed between plant species, with thicker leaves generally being cut into smaller pieces. Significant linear correlations were found between total daily harvest of fragments and the respective harvesting rate at the maximum of daily activity. High correspondence was found between estimates using this relationship and the measured daily leaf harvest of four otherAttacolonies and of two colonies reported in published literature. The use of this relationship as a research tool is discussed.
Peoecological evidence ofRaphiain the Pre-Columbian Neotropics
Authors: Urquhart Gerald R. 
Published: July 2009

ABSTRACTDisjunctions between Africa and the Neotropics present a puzzle that is key to understanding the biogeography of the diverse floras and faunas of both continents. Many authors have proposed thatRaphia taedigeraMaur., the sole Neotropical representative of an otherwise African genus, has been introduced to the New World. Paleoecological data from a freshwater swamp in Nicaragua, which yieldedR. taedigerapollen dating to 2800 ± 90 y before present (BP) andRaphiaseed fragments from 2040 ± 60 BP are presented. These illustrate thatRaphia taedigeraarrived in the New World before trans-Atlantic trade by humans and thus arrived as a result of a natural phenomenon. The lack of differentiation ofR. taedigerafrom the African sister taxon,R. vinifera, suggests recent separation of the two species (i.e. after the creation of the southern Atlantic Ocean by the splitting of West Gondwana). Other evidence supports dispersal ofRaphiaby ocean currents. The palm probably arrived from Africa by floating as an individual fruit or on a raft of vegetation. Thus,R. taedigerarepresents another example of trans-Atlantic dispersal, strengthening the link between the flora and fauna of Africa and the Neotropics.
Germination ecology of forest species from the highlands of Ethiopia
Authors: Teketay Demel , Granström Anders 
Published: July 2009

ABSTRACTA comparative study of seed germination was performed on 25 species of trees, shrubs, woody climbers and herbs from the dry Afromontane forest zone of Ethiopia. Despite the restricted geographical range of the species tested, the optimum constant temperature for germination varied considerably. For 17 of the species studied, it was between 20 and 25 °C while for three, germination was highest at 30 °C Germination was virtually inhibited (<20%) for eight of the species at 10 °C and eight of the species at 30 °C. There was no clear division in temperature response between plants differing in habitat. For four out of 12 species tested, fluctuating temperatures (20/12 °C) resulted in significantly higher germination than the constant temperature treatment (20 °C), suggesting that field-germination would be favoured by disturbance to the canopy or soil. Speed of germination was negatively correlated with the logarithum of seed size. Most species lay in the range 3–15 d to reach 50% of final germination at their optimum temperature for germination. Germination was significantly suppressed in darkness for a large number of species, particularly for those with seed size less than c. 3 mg. When these were incubated under leaf-filtered light, germination was in most cases even more effectively suppressed. Most of these species are known to have large soil seed banks. Mechanical scarification improved germination over the control in nine species. Five of these also reponded to heat or sulphuric acid scarification. Circumstantial evidence suggests that the species showing heat-induced germination may be fire adapted, although fire is probably a rare natural phenomenon in the Afromontane forest proper. Only one species, Bersama abyssinica, showed a classic recalcitrant behaviour. Germination dropped from 88% when the seeds were fresh to less than 20% after 1 mo of dry storage and 0% after 3 mo. Germinability of seeds of Ekebergia capensis also declined significantly with increasing storage time, although less rapidly; after 24 mo of dry storage, germination was 4%. In contrast, germinability of Juniperus procera was not significantly altered during 54 mo of storage. The results indicate that dormancy plays a major role in regulating germination in dry Afromontane species. Out of the 25 species studied, 15 (60%) showed some degree of initial dormancy. In most of the species with initially non-dormant seeds, dormancy would evidently be induced if the seeds are dispersed under a closed forest canopy or buried in the soil. These patterns of dormancy may have evolved in response to a highly unpredictable climate and small-scale disturbances, and should make the Afromontane forest flora relatively resilent also to anthropogenic disturbances.
Estimating the ages of successional stands of tropical trees from growth increments
Authors: Terborgh John , Flores N. Cesar , Mueller Peter , Davenport Lisa 
Published: July 2009

ABSTRACTInability to age tropical trees has imposed major limitations on the basic and applied science of tropical forests. Here advantage was taken of even-aged stands present in successional chronosequences found on Amazonian Whitewater river meanders to simplify the assumptions needed to estimate tree ages from growth measurements. Growth increments of eight common early successional species were measured in 21 0.5-ha plots evenly distributed over chronosequences from the earliest post-pioneer stage to mature Ficus-Cedrela stands representing approximately the mid-point of primary succession. Increment measurements, based on 4 or 5 y of growth, were arrayed in scatter diagrams against the midpoints of the growth intervals. A loess regression of the points, weighted for the higher mortality of slow-growing individuals, was then conducted to generate a ‘best estimate lifetime growth trajectory’ (BELGT) of a ‘typical’ individual surviving to maturity. The BELGT curves were integrated to generate a set of derived curves describing the time required by a ‘typical’ surviving individual to attain any given size up to the maximum for the species. Predictions of the ages of particular stands were derived from these latter curves and found to agree within 3 to 20% of ages independently estimated from the rate of point bar accretion.
Genetic diversity of PhilippineRubus moluccanusL. (Rosaceae) populations examined with VNTR DNA probes
Authors: Busemeyer Daniel T. , Pelikan Stephan , Kennedy Robert S. , Rogstad Steven H. 
Published: July 2009

ABSTRACTTwo synthetic DNA probes composed of tandemly repeated ‘core’ sequences (GACA and GATA) were used to examine genetic diversity at multiple variable-number-tandem-repeat (VNTR) loci within and among four spatially isolated Philippine populations ofRubus moluccanusL. (Rosaceae), an uncultivated bramble widely distributed throughout southeast Asia – Malesia. Central goals were to determine whether apomictic propagation was detectable inR. moluccanusand to examine whether populations isolated on separate islands, or on mountain tops on a single island, were genetically differentiated. Sampling 22 individuals per population, the findings include: (1) no two individuals shared identical VNTR band profiles and thus apomictic propagation was not detected; (2) the mean number of bands scored per individual was 24.3 (SD = 3.91) and the proportion of polymorphic loci within populations ranged from 0.69 to 1.00 (mean = 0.86 ± SD = 0.085); (3) the average proportion of bands shared between individuals within populations ranged from 0.39 to 0.67 (0.50 ± 0.067), while average interpopulation similarity ranged from 0.21 to 0.50 (0.32 ± 0.092); and (4) estimated heterozygosity within populations ranged from 0.42 to 0.79 (0.62 ± 0.083), while interpopulation heterozygosity ran from 0.62 to 0.81 (0.74 ± 0.062). Permutation tests were used to estimate the statistical significance of differences in similarity between populations. A Luzon population isolated by 1200 km was always significantly different in similarity tests when compared with each of the other three populations, all located on Mindanao (and separated by at least 100 km but less than 250 km). Of the latter three, only one population differed significantly from the other two in the degree of VNTR markers shared, possibly reflecting biogeographic partitioning suggested for the island. Across all populations, average estimated Fst was 0.154, although mean inter-island Fst (0.224) was significantly higher than mean intra-island Fst (0.085). These results suggest that, while intra-island gene flow is relatively high, significant differentiation of tropical species may occur even over short distances on individual islands. Preservation of only a limited number of populations may result in a significant loss of genetic diversity in such species.
Second-hand consumption as a way of life: public auctions in the surroundings of Alost in the late eighteenth century
Authors: DAMME ILJA VAN , VERMOESEN REINOUD 
Published: July 2009

AbstractThis article seeks to place second-hand consumption, or the reuse of older objects, into the expanding historical literature on early modern consumer practices. It claims that the study of second-hand consumption remains a much neglected topic of historical interest. Further empirical research of pre-industrial reuse habits is needed to examine essential problems and inconsistencies concerning consumers and their handling of older goods. On the basis of rarely used sources relating to public auctions in the countryside of the southern Netherlands, key questions regarding the current debate will be addressed. These questions concern the products that were handled, the actors involved, and how reuse was (or was not) affected by broader changes in society.
Changes in Old Bailey trials for the murder of newborn babies, 1674–1803
Authors: CLAYTON MARY 
Published: July 2009

AbstractAlthough women accused of murdering their newborn infants were tried under the 1624 Act to Prevent the Destroying and Murdering of Bastard Children throughout the eighteenth century, their treatment changed significantly, at least in London, between the last quarter of the seventeenth century and 1803. This article charts these changes through an analysis of the accounts of trials held at the Old Bailey. These reflect three interwoven and interdependent strands of change: the development of a range of successful defence strategies, changes in courtroom procedures and the increased participation of lawyers, and a greater use of and reliance on medical witnesses and their evidence.