Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 20 of 30 for “"canopy gaps"”.
-
Spatial distribution of canopy gaps in a tropical forest landscape and its influence on the tree community
… In old growth tropical forests, the creation of canopy gaps by one or multiple tree falls is one of the main causes of disturbance and thus potentially one of the main drivers of forest dynamics (Swaine and Whitmore 1988). My thesis focuses on characterizing patterns of gap disturbance across a …
-
Light microsite requirements of seedlings of some Afromontane forest tree species: the role of canopy gaps promoting regeneration
… forest, where frequency of seedlings beneath the canopy and under a canopy gap were recorded and tested using a x²-goodness of fit test, against the null hypothesis that there are equal frequencies of seedlings beneath the canopy and canopy gaps. Results confirmed predictions made for latifolius, …
-
The effects of age and size of canopy gaps on the mycorrhizae of yellow birch (Betula alleghaniensis Britton) and sugar maple (Acer sacchrum Marsh.) from deciduous forests of the Québec city region
Effects of different sized and different aged canopy gaps on the ectomycorrhizae of yellow birch and vesicular-arbuscular mycorrhizae of sugar maples collected from two deciduous forests in central Quebec were examined. The colonization of maple roots by arbuscules, vesicles, and coils were …
-
Long-term patterns of mortality and regeneration in near-natural woodland
… shrubs, established seedlings, dead wood and canopy gaps.<br></br>2. The stands inherited various original-natural features and grew away from a managed state. Nonetheless, their structure and composition remained heavily influenced by past treatment and non-native species.<br></br>3. The …
-
Regeneration Dynamics in Old -Growth and Second-Growth Southern Appalachian Cove Forests
… the two sites, but was significantly higher in canopy gaps in the old-growth site. Results of multivariate direct gradient analyses indicated that light availability played an important and often significant role in the distribution of species in the study sites and in several measures of …
-
Coordination of physiological and morphological acclimation of shade-grown tree saplings to late-season canopy gap formation
… saplings respond positively to late-season canopy gaps, then morphological and physiological changes at both the organ and whole-plant level will result in greater carbon gain of saplings exposed to gaps relative to saplings remaining in the shade; that is, shade-developed saplings will …
-
Negative Effects Of ComMycorrhizal Networks And Roots On Upland Oak Seedlings In Open-Canopy Woodlands And Closed-Canopy Forests
… of seedlings in the shade and growth within canopy gaps. Through the sharing of carbon and/or water between adults and seedlings, connection to a commycorrhizal network potentially provides a mechanism by which oak seedlings could persist in shade and/or grow rapidly in dry soils within …
-
Applications of Imaging Spectroscopy in Forest Ecosystems at Multiple Scales
… loblolly pine nutrient status at the leaf and canopy scales, respectively. The first study determined that loblolly pine foliar macronutrient concentrations can be successfully modeled across the Southeastern US (R2=0.39-0.74). Following on these results, the second study focused on the …
-
The soil seed bank in Agathis australis (D. Don) Lindl. (kauri) forests of northern New Zealand and its potential role in secondary successions
… from forest edges. 4. The soil seed bank, canopy gaps and gap regeneration strategies. 5. The nature of the soil seed bank and soil properties. 6. The fruiting phenology, seed rain, and soil seed bank dynamics. The forest sites ranged from 50 years to over 1,000 years old, while distance …
-
The Regeneration Niche in Bottomland Hardwood Forests: Tree and Herbaceous Communities Along Interacting Gradients of Flood and Light in East Texas Floodplains
… tolerance. Field surveys demonstrated that small canopy gaps in BLH forest support shade-tolerant tree seedlings and increase understory plant diversity, but suppress shade-intolerant hardwoods such as oaks and hickories. A complementary greenhouse study demonstrated that two oak species exhibited …
-
Identifying structural differences in mixed mesophytic and northern hardwood forests on the Monongahela National Forest using remote sensing data
… of larger trees, snags, log accumulations, and canopy gaps, compared to 50--69 year old stands. The 70--89 stands were more similar in structural characteristics to the stands >90 years old than to the 50--69 year stands.;Texture analysis, single band, and color-ratio techniques applied to SPOT …
-
The Impact of Prohexadione-calcium on Grape Vegetative and Reproductive Development and Wine Chemistry
… Seyval. P-ca (375 mg/L) increased Cabernet franc canopy gaps but increased Cabernet Sauvignon lateral leaf area and leaf layer number. P-ca reduced components of yield for all cultivars. In 2001, P-ca (250 mg/L) was applied singularly at weekly intervals to Cabernet Sauvignon clusters and pre and …
-
Ice storms as a disturbance factor in Appalachian oak forests
… resistant equilibrium species would then fill canopy gaps, shifting the stand to a more advanced stage. Alternatively, extensive canopy damage allows more light to reach the forest floor perhaps favoring the germination and establishment of pioneer seedlings. Survival of these individuals would …
-
Sapling growth and recruitment as affected by flooding and canopy gap formation in a river floodplain forest in southeast Texas
… data collected since 1980 to investigate how canopy disturbance interacts with chronic understory disturbance to determine regeneration patterns. I reconstructed flooding history using a combination of river gauging, a local water-level recorder, and contour maps. 1979 was an extreme flood …
-
Barrier Effects Of Roads And Traffic On Animal Occurrence, Space Use, And Movements
… and assessed effects of traffic, road edges, and canopy gaps on space use of Mt. Graham red squirrels and compared to the response of introduced, edge-tolerant Abert's squirrels (Sciurus aberti). Forest roads acted as partial barriers for red squirrels regardless of traffic volume likely due to …
-
Growth release of trees following fine-scale canopy disturbances in old-growth forests of coastal British Columbia, Canada
Growth release of trees following canopy disturbances is of interest to ecological scientists and forest managers. Using dendroecological techniques, I examined growth release of canopy and subcanopy trees following the formation of natural, fine-scale canopy gaps in old-growth, western red …
-
Vegetation community development eight years after harvesting in small streams buffers at the Malcolm Knapp Research Forest
… was measured annually from the year of harvest. Canopy density was measured using a densiometer. For comparative purposes, four vegetation plots were added in riparian areas within an 1868 and an old-growth stand during the summer of 2006. Eight years after harvesting, understory vegetation …
-
PATTERNS OF SEEDFALL AND SEEDLING ESTABLISHMENT IN AN EAST TEXAS RIVER FLOODPLAIN FOREST: THE CONTRIBUTION OF SEEDLING DYNAMICS TO SPECIES COEXISTENCE (PLANT DEMOGRAPHY, DISPERSAL, TREE REGENERATION, SURVIVORSHIP, MORTALITY)
… leads to differential species success in canopy openings by favoring species currently important as seedlings. As a test of this hypothesis, seedling survival and abundance in the understory were compared to sapling abundance in nearby canopy gaps. Results for both sweetgum and water oak …
Page 1 of 2