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.
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Showing 1 to 16 of 16 for “"tree species diversity"”.
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Modelling spatial turnover patterns in tree species diversity for conservation
The planet’s biodiversity is increasingly threatened by the effects of rapid environmental change. Biodiversity loss led by expanding anthropogenic activity, combined with the effects of changing climatic regimes, pose a threat to natural communities and the ecosystem services that they underpin. …
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Productivity and nutrient relations of trees in deciduous forests differing in tree species diversity
Die Effekte der Biodiversität auf die Ökosystemfunktionen von Wäldern werden mit steigendem Interesse diskutiert. Ein Schwerpunkt der Debatte liegt dabei auf dem Einfluss der Artenzahlen als auch der funktionellen Gruppen auf verschiedene Ökosystemfunktionen, wie zum Beispiel der Primärproduktion, …
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Geographic distribution of tree species diversity of the United States reveals positive association between biodiversity and site productivity
With the loss of species worldwide due to anthropogenic factors, especially in forested ecosystems, it has become more urgent than ever to understand the biodiversity-ecosystem functioning relationship (BEFR). BEFR research in forested ecosystems is very limited and thus studies that incorporate …
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Modeling scenic quality of residential streets using mensurational variables
… to predict scenic quality for residential streets in Ann Arbor, Michigan for both Summer and Winter vegetative conditions. Scenic quality was quantified using the Scenic Beauty Estimation method. Only variables that existed in the city's computer data base were used. Variables such as …
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The Direct and Indirect Effects of Insectivory by Birds in Two Neotropical Forests
… and restricted to saplings in relatively low diversity systems. In two lowland tropical forests, I tested whether birds indirectly defend canopy and understory plant foliage from arthropod herbivores. The two forest sites differed in age, tree species diversity and rainfall seasonality. Birds …
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Effects of Wildfire Intensity on Invasives, Stand Structure and Fuel Loading in Shenandoah National Park
As invasive species are so prominent, the influence of wildfire intensity on fuel loading, invasives, species richness, diversity, and evenness were studied at Shenandoah National Park. Most National Parks identify invasive species as the biggest threat to their goal of maintaining native …
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Effects of different canopy tree species on belowground biogeochemistry in a wet lowland tropical forest
… are known for their tremendous biological diversity, but the effects of plant diversity on important ecosystem processes remain unclear. Interspecies differences in both the demand for nutrients and in foliar nutrient concentrations could drive differences in litter chemistry that affect …
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Effects of different canopy tree species on belowground biogeochemistry in a wet lowland tropical forest
… are known for their tremendous biological diversity, but the effects of plant diversity on important ecosystem processes remain unclear. Interspecies differences in both the demand for nutrients and in foliar nutrient concentrations could drive differences in litter chemistry that affect …
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Relationship of Forest Characteristics and Landscape Patterns To Wild Turkey Populations in Eastern and Central South Dakota
… populations, but are currently lacking turkeys. Tree species diversity was greatest in deciduous forests of northeastern South Dakota which included Roberts, Marshall, and Jerauld counties. The means of nineteen landscape and forest characteristic variables were compared among the most forested …
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Modeling avifauna responses to miombo woodland degradation in Serenje district, Central province, Zambia
… plots. PC-ORD © was used to determine plant species composition and structure from plant species presence data and DBH data of the woody vegetation in each plot. Principal Component Analysis and Cluster Analysis using SPSS © were used to identify the principal vegetation variables as well as …
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Modeling avifauna responses to miombo woodland degradation in Serenje district, Central province, Zambia
… plots. PC-ORD © was used to determine plant species composition and structure from plant species presence data and DBH data of the woody vegetation in each plot. Principal Component Analysis and Cluster Analysis using SPSS © were used to identify the principal vegetation variables as well as …
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Interactions among tree species and pathogen-suppressive bacteria in tropical forest soils
… plant pathogens are thought to regulate diversity by driving negative plant-soil feedbacks and promoting density-dependent mortality of seedlings close to parent trees. Pathogens interact with a myriad of other organisms in soil that have the potential to moderate plant disease and in …
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Vegetation Responses to Seven Silvicultural Treatments in the Southern Appalachians One-Year After Harvesting
… shelterwood, 5) low-leave shelterwood, 6) leave tree, and 7) clearcut. The effects of harvesting were compared between treatments and between pre-harvest and post-harvest samplings. Species richness, percent cover, and local species extinctions were calculated for sample plots ranging in size …
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The impacts of seven silvicultural alternatives on vascular plant community composition, structure, and diversity in the southern Appalachians
… (5) low-leave shelterwood, (6) leave tree, and (7) clearcut. The effects of each treatment on the vascular plant community were characterized by changes in species diversity, species composition, exotic species richness, Raunkiaer's life-forms, and growth-forms. Pre-treatment, baseline …
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Relationships between soil chemical properties and forest structure, productivity and floristic diversity along an altitudinal transect of moist tropical forest in Amazonia, Ecuador.
Entlang eines Höhentransektes von ungestörten höheren Tiefland zu montanen Primärwäldern in Nordost Ecuadors, im Gebiet des Sumaco Biosphären Reservates (SBR), untersuchten wir die die Hypothesen, dass (1) die Verfügbarkeit von Phosphor niedrig ist in den tiefer gelegenen Wäldern und mit …