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Irwin Mitchell T - - 2007
Forest fragmentation is thought to threaten primate populations, yet the mechanisms by which this occurs remain largely unknown. However, fragmentation is known to cause dietary shifts in several primate species, and links between food resource distribution and within-group spatial dynamics are well documented. Thus, fragmentation has the potential to indirectly ...
Nyquist B - - 2007
In this paper, we present a model for source-sink population dynamics where the locations of source and sink habitats change over time. We do this in the context of the population dynamics of the North American red squirrel, Tamiasciurus hudsonicus, within a forest environment subject to harvesting and regrowth. Harvested ...
Iwai Noriko - - 2007
In aquatic food webs consumers can affect other members of the web by releasing nutrients as a result of their feeding activity. There is increasing evidence of these positive effects on primary producers, but such nutrient regeneration can also affect detritivores, by favoring the activities of detritus-associated microbes. We examined ...
Herbinger K - - 2007
Three-year-old beech (Fagus sylvatica) seedlings growing in containers were placed into the sun and shade crown of a mature beech stand exposed to ambient (1 x O(3)) and double ambient (2 x O(3)) ozone concentrations at a free-air exposure system ("Kranzberg Forst", Germany). Pigments, alpha-tocopherol, glutathione, ascorbate, and gas exchange ...
Beres B L - - 2007
The wheat stem sawfly, Cephus cinctus Norton (Hymenoptera: Cephidae), has reached outbreak status at most locations in the southern Canadian prairies. Solid-stemmed wheat, Triticum aestivum L., cultivars, which are less susceptible to damage, remain the primary management option. This article quantifies the effect of wheat stem sawfly damage on grain ...
Prasad V Krishna - - 2008
Forest fires constitute one of the most serious environmental problems in several forested regions of India. In the Indian sub-continent, relatively few studies have focused on the assessment of biophysical and anthropogenic controls of forest fires at a landscape scale and the spatial aspects of these relationships. In this study, ...
Marshall Andrew J - - 2007
The Indonesian province of East Kalimantan is home to some of the largest remaining contiguous tracts of lowland Dipterocarp forest on the island of Borneo. Nest surveys recently conducted in these forests indicated the presence of a substantial population of Eastern Bornean orangutans (Pongo pygmaeus morio) in the Berau and ...
Basile Boris - - 2007
We compared growth patterns and morphology of fine roots of size-controlling and invigorating peach (Prunus persica (L.) Batsch) rootstocks. Peach trees were grafted on five rootstocks: a vigorous control (Nemaguard), three intermediate vigor rootstocks (K119-50, P30-135 and Hiawatha), and a semi-dwarfing rootstock (K146-43). Minirhizotron tubes were installed at the base ...
Chitwood Daniel H - - 2007
The flattening of leaves results from the juxtaposition of upper (adaxial) and lower (abaxial) domains in the developing leaf primordium. The adaxial-abaxial axis reflects positional differences in the leaf relative to the meristem and is established by redundant genetic pathways that interpret this asymmetry through instructive, possibly non-cell autonomous, signals. ...
Barabé Denis - - 2007
BACKGROUND AND AIMS: By using the technique of replicas of a developing apex it is possible to obtain a direct measure of phyllotactic parameters (plastochrone and platochronic ratio) involved in the initiation of two successive primordia at the level of the SAM. The goal of this study is to compare, ...
Parton William - - 2007
Litter decomposition provides the primary source of mineral nitrogen (N) for biological activity in most terrestrial ecosystems. A 10-year decomposition experiment in 21 sites from seven biomes found that net N release from leaf litter is dominantly driven by the initial tissue N concentration and mass remaining regardless of climate, ...
Lehman Shawn M - - 2007
I present data on variations in Eulemur fulvus rufus and Lepilemur mustelinus densities as well as tree characteristics (height, diameter and stem frequency) between edge and interior forest habitats in southeastern Madagascar. Line transect surveys were conducted from June 2003 to November 2005 in edge and interior forest habitats in ...
Simon F - - 2007
European or Persian Walnut (Juglans regia) is an important and healthy food as well as base material of timber industry. Several pests (pathogens and insect pests) may cause serious damages on walnut. These are less known on the crop land of the tree. Results of some years of our experiments ...
Hardman J M - - 2007
We sampled mites in three apple orchards in Nova Scotia, Canada, that had been inoculated with pyrethroid-resistant Typhlodromus pyri and had a history of Tetranychus urticae outbreaks. The objective of this study was to monitor populations of T. urticae and phytoseiid predators on the ground and in trees and to ...
Hammen V C - - 2007
Smoke-haze episodes caused by vegetation and peat fires affect parts of Indonesia every year with significant impacts on human health and climate. The forest fires 1997/1998 were by far the largest in Indonesian history, burning between 5 and 8 million hectares before they were stopped by the monsoon rains in ...
Morton Katherine M - - 2007
Epididymal spermatozoa were harvested from male alpacas and frozen after extension and cooling to 4 degrees C in citrate-, Tris- and lactose-based diluents (Experiment 1) and as pellets in 0.25- and 0.5-mL straws on either dry ice or over liquid nitrogen vapour (Experiment 2) to determine the effects diluents and ...
Sevgi Orhan - - 2007
This study was carried out to investigate the relationship between tree ring widths of Pinus nigra in Kazdaglari having humid and very humid climatic conditions. Sixty two trees were cut from 24 sampled points from different altitudes in Kazdaglari to measure treering widths. To determine the responses to the climate, ...
Wedmann Sonja - - 2007
Stick and leaf insects (insect order Phasmatodea) are represented primarily by twig-imitating slender forms. Only a small percentage ( approximately 1%) of extant phasmids belong to the leaf insects (Phylliinae), which exhibit an extreme form of morphological and behavioral leaf mimicry. Fossils of phasmid insects are extremely rare worldwide. Here ...
Kitzberger Thomas - - 2007
Widespread synchronous wildfires driven by climatic variation, such as those that swept western North America during 1996, 2000, and 2002, can result in major environmental and societal impacts. Understanding relationships between continental-scale patterns of drought and modes of sea surface temperatures (SSTs) such as El Niño-Southern Oscillation (ENSO), Pacific Decadal ...
Tian Q - - 2007
Spatial distributions of the leaf area index (LAI) needed for carbon cycle modeling in Xingguo County, China were estimated based on correlations between the field-measurements and vegetation indices (VIs). After making geometric and atmospheric corrections to two Landsat ETM+ images, one in January 2000 and the other in May 2003, ...
Sorvari Jouni - - 2007
Sex ratios of ants have been shown to vary with food resource levels in several studies, but it is not known whether forest clear-cutting has any effect on sex ratio of aphid-tending forest-dwelling ants. We investigated whether the offspring sex ratio of the forest dwelling ant Formica aquilonia varied as ...
Kaiser Hartmut - - 2007
The response of stomata to a reduction of air humidity is composed of a hydropassive opening followed by active closure. Whereas the mechanisms behind the hydropassive opening are largely understood, the location and physiological basis of the sensing mechanisms leading to active closure are not yet known. This study attempts ...
Greenwood Jennifer L - - 2007
Most nutrient enrichment studies in aquatic systems have focused on autotrophic food webs in systems where primary producers dominate the resource base. We tested the heterotrophic response to long-term nutrient enrichment in a forested, headwater stream. Our study design consisted of 2 years of pretreatment data in a reference and ...
Cameron Elissa Z - - 2007
With their vertically elongated body form, giraffes generally feed above the level of other browsers within the savanna browsing guild, despite having access to foliage at lower levels. They ingest more leaf mass per bite when foraging high in the tree, perhaps because smaller, more selective browsers deplete shoots at ...
Silpi Unakorn - - 2006
Rubber tree (Hevea brasiliensis Müll. Arg.) radial growth dynamics were monitored with displacement sensors, together with latex production, to investigate three aspects of the dual production of latex and wood: (1) the usefulness of fine-scale dendrometric measurements as a physiological tool to detect water shortage through radial growth; (2) the ...
Chapman Colin A - - 2006
Identifying factors that influence animal density is a fundamental goal in ecology that has taken on new importance with the need to develop informed management plans. This is particularly the case for primates as the tropical forest that supports many species is being rapidly converted. We use a system of ...
Hogewoning Sander W - - 2007
The effect of chilling on photosystem II (PSII) efficiency was studied in the variegated leaves of Calathea makoyana, in order to gain insight into the causes of chilling-induced photoinhibition. Additionally, a relationship was revealed between (chilling) stress and variation in photosynthesis. Chilling treatments (5 degrees C and 10 degrees C) ...
Sentelhas Paulo C - - 2007
In general, leaf wetness duration (LWD) is a key parameter influencing plant disease epidemiology, since it provides the free water required by pathogens to infect foliar tissue. LWD is used as an input in many disease warning systems, which help growers to decide the best time to spray their crops ...
Sullivan Patrick F - - 2007
Leaf carbon isotope discrimination (Delta(13)C) varies with the balance between net photosynthesis (A) and stomatal conductance (g ( s )). Inferences that can be made with Delta(13)C are limited, as changes could reflect variation in A and/or g ( s ). Investigators have suggested that leaf delta(18)O enrichment above source ...
Milner, Jos; University of ...
A brief study was carried out in South-West Mau region of the Mau Forest Complex in March 1993. The primary aim was to assess the importance of the tree hyrax, <i>Dendrohyrax arboreus</i> (A. Smith, 1827), to the local forest-dwelling people as a source of food and medicine and in their ...
Sarijeva Gulmira - - 2007
The differences in pigment levels and photosynthetic activity of green sun and shade leaves of ginkgo (Ginkgo biloba L.) and beech (Fagus sylvatica L.) are described. Sun leaves of both tree species possessed higher levels in chlorophylls (Chl) and carotenoids on a leaf area basis, higher values for the ratio ...
Lepoint, Gilles
This study focused on the ingestion and assimilation of Posidonia oceanica (L.) Delile litter by Gammarella fucicola Leach and Gammarus aequicauda Martynov, two dominant detritivore amphipods of the P. oceanica leaf litter. Scanning electron microscope observations indicated that leaf litter is highly colonized by diverse diatoms, bacteria and fungi, which ...
Gwo J-C - - 2006
The general sperm structure of the investigated clupeoids possess an oliviform head with a distinct deep nuclear fossa, a midpiece with one mitochondrion and a posterior flagellum. They are characterized by two apomorphies: an annular or C-shaped mitochondrion and ITDs (intratubular differentiation) in the A tubules of the axonemal doublets. ...
Freeland, W. J.
While being somewhat specialized on a diet of mature Eucalyptus leaves (66% of feeding time), wild Trichosurus vulpecula consume an average of three different foods per night. Usually, these foods are two different species of Eucalyptus leaves, and “ground feeding.” Laboratory feeding experiments indicate that this ingestion of a variety ...
Tanaka K - - 2006
Miso (fermented soybean paste), shoyu (soy sauce) and sake (rice wine) are traditional moldfermented foods in Japan and have been consumed throughout much of its history. These have long been considered safe foods. In this contribution we review and summarize long-term studies to investigate potential problems with mycotoxin contamination of ...
Savage G P - - 2006
Pacific Island people commonly eat taro (Colocasia esculenta var. Schott) as a staple food in their home islands and also like to consume this familiar food when living in New Zealand. Some of these foods are imported from the islands and some attempts are, currently, being made to grow these ...
Tambunan Parlindungan - - 2006
This study surveyed isoprene emission from 42 indigenous and exotic tropical trees in subtropic Okinawa, Japan. Of the 42 trees studied, 4 emitted isoprene at a rate in excess of 20 microg g(-1)h(-1), and 28 showed the rates of 1-10 microg g(-1)h(-1). The remainder emitted less than 1 microg g(-1)h(-1). ...
van der Straten K M - - 2006
As a first step towards the development of a method for the cryopreservation of black marlin spermatozoa, this study investigated the effect of dimethylsulfoxide (DMSO) concentration and pellet size on post-thaw spermatozoal motility. Spermatozoa were recovered from the spermatic duct of testes retrieved post-mortem from four adult black marlin caught ...
Janmaat Karline R L - - 2006
Temperature and solar radiation are known to influence maturation of fruits and insect larvae inside them . We investigated whether gray-cheeked mangabeys (Lophocebus albigena johnstonii) of Kibale Forest, Uganda, take these weather variables into account when searching for ripe figs or unripe figs containing insect larvae. We predicted that monkeys ...
Ward Tony J - - 2006
Tree bark and core samples were collected from areas surrounding the asbestos-contaminated vermiculite mine in Libby, MT. These samples were collected to provide preliminary data in support of a proposed study to determine if trees can serve as reservoirs for amphibole fibers and to determine if there is a potential ...
Swan Christopher M - - 2006
Forest soils and streams receive substantial inputs of detritus from deciduous vegetation. Decay of this material is a critical ecosystem process, recycling nutrients and supporting detrital-based food webs, and has been attributed, in part, to leaf litter species composition. However, research on why speciose leaf litter should degrade differently has ...
Young J A - - 2006
In 2002, Tennis Australia commissioned a report into the experiences of elite female past players on leaving the professional tennis circuit. Australian players who were in the top 800 of the Women's Tennis Association (WTA) end of year rankings and who had left the professional circuit within the previous 15 ...
Lovelock Catherine E - - 2006
Spatial gradients in mangrove tree height in barrier islands of Belize are associated with nutrient deficiency and sustained flooding in the absence of a salinity gradient. While nutrient deficiency is likely to affect many parameters, here we show that addition of phosphorus (P) to dwarf mangroves stimulated increases in diameters ...
Galantino-Homer Hannah L - - 2006
Porcine sperm are extremely sensitive to the damaging effects of cold shock. It has been shown that cholesterol-binding molecules, such as 2-hydroxypropyl-beta-cyclodextrin (HBCD), improve post-cooling porcine sperm viability when added to an egg yolk-based extender, but also enhance sperm capacitation in other species. The objective of this study was to ...
Moldan F - - 2006
Beginning in 1991, we have added nitrogen (N) to the 0.5-ha, N-poor, coniferous-forested catchment G2 NITREX at Gårdsjön, Sweden, to investigate the consequences of chronic elevated N deposition. We have added 40 kg N ha-1 yr-1 in fortnightly doses of NH4NO3 to the ambient 15 kg N ha-1 yr-1 by ...
Sala Anna - - 2006
As trees grow tall and the resistance of the hydraulic pathway increases, water supply to foliage may decrease forcing stomata to close and CO2 uptake to decline. Several structural (e.g. biomass allocation) and physiological adjustments, however, may partially or fully compensate for such hydraulic constraints and prevent limitations on CO2 ...
Gibb A R - - 2006
Gas chromatography-electroantennographic detection analysis of sex pheromone gland extracts of the common forest looper Pseudocoremia suavis (Lepidoptera: Geometridae), a polyphagous defoliator of introduced Pinaceae and many New Zealand trees, revealed four compounds that elicited antennal responses. The two major active compounds (6Z)-cis-9,10-epoxynonadec-6-ene and (3Z,6Z)-cis-9,10-epoxynonadeca-3,6-diene were identified by comparison with known ...
Raghuvansi S K S - - 2007
The effect of inclusion of tree leaves in mustard (Brassica campestris) straw (MS) based complete feed blocks (CFB) on nutrient utilization and rumen fermentation was studied in adult male sheep. Four types of CFB diets (Roughage:Concentrate:Molasses, 70:25:5) were prepared. The compaction process increased bulk density (g/cm(3)) of MSB, MSNL, MSSL ...
Norghauer Julian M - - 2006
According to the Janzen-Connell model, high mortality of seeds and seedlings in proximity to conspecific adults can help maintain species diversity in tropical forests. Using a natural population of big-leaf mahogany (Swietenia macrophylla King), we tested the model's mechanism by examining seed predation and juvenile recruitment in the forest understory ...
Lehman Shawn M - - 2006
Forest edges are dynamic zones characterized by the penetration (to varying depths and intensities) of conditions from the surrounding environment (matrix) into the forest interior. Although edge effects influence many tropical organisms, they have not been studied directly in primates. Edge effects are particularly relevant to lemurs because of the ...
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