Conservation of biodiversity is a major issue in ancient temperate rainforests of British Columbia. While significant efforts have been made to document species of birds and mammals, little is known about canopy arthropod communities in British Columbia. Microhabitats (suspended soils) within canopy systems of temperate rainforests support diverse microarthropod communities, dominated by mites of the suborder Oribatida. These oribatid mite communities are distinct from forest floor communities, contribute significantly to overall forest biodiversity, and are functionally important components of forest ecosystems. I used the suspended soil system in western redcedar trees in the Walbran Valley to study the relative importance of local environmental factors versus regional spatial factors contributing to the structure of arboreal oribatid mite communities. and compare these patterns to forest floor oribatid mite communities at the same study location. An array of sampling methods was used to complete these objectives: substrate core samples. bark scrapings, colonisation of litterbags, litterfall collection, and colonisation of artificial canopy habitats. This study identified 138 species of oribatid mites associated with ancient western redcedar trees of the Walbran Valley on Vancouver Island. The documented patterns of oribatid mite diversity in this rainforest demonstrated higher local species richness (alpha diversity) in terrestrial (forest floor) habitats, and greater beta diversity in arboreal (suspended soil) habitats. The oribatid mite community within suspended soils are formed primarily by dispersal patterns and colonisation within the canopy system. with limited colonisation from the forest floor. The factors, which shape canopy oribatid mite communities within suspended soils, are related to habitat availability, moisture limitation and random dispersal events of individual species. My results suggest the arboreal oribatid mite community experiences regional dispersal limitation associated with physical tree-to-tree dispersal barriers. However, factors other than physical dispersal barriers. such as aggregation and niche partitioning, likely also limit the local distribution of species in both arboreal and terrestrial habitats. Stochastic dispersal dynamics within the canopy are crucial to understanding oribatid mite community structure in suspended soils. yet the relative importance of regional dispersal processes is dependent on deterministic factors relating to the environmental tolerances of individual species at the local scale.

Thesis (M. A.)--University of Canterbury, 2007. / Typescript (photocopy). Includes bibliographical references (leaves 122-130). Also available via the World Wide Web.

Thesis (Ph. D.)--UCLA, 2009. / Vita. Includes bibliographical references.

Made available in DSpace on 2016-04-28T20:12:51Z (GMT). No. of bitstreams: 1 2001-Rosa Maria Roldan Santa Isabel.pdf: 725603 bytes, checksum: 9f180504ca688bf5c1a11c8f75e719b0 (MD5) Previous issue date: 2001-03-15 / The current study deals with two proposals, which are being developed in Extractive Reserves in Acre State, aiming its sustainable development. The construction of this kind of alternatives for agro extractivist populations of this region represents a challenge. The main objective is to characterize, analyze and understand the political, economical, cultural and social meanings of the projects: The Forest Handling of the Multiple Usage of the PAE Porto Dias and High Productivity Island Rationalization of the Extraction of Gum in Extractive Areas . The study of these two proposals considers the situation of logging in the Amazon region as well as the social and political context of Acre State, particularly the opportunities arisen after the election of representatives of the popular movements for the State Government. Its analyses can be a step forward in the development of these projects, which aim at the improvement of life conditions for the extractivist workers and for the environment. We believe in the alternative of a new extractivism, defended by the IAPs project, for its characteristics of partnership, which strength the culture of rubber tappers, with a perspective of economical feasibility, recovering devastated areas and respecting forest s biodiversity. The methodology used gave a special importance to fieldwork with interviews and complementary data obtained from those involved direct or indirectly with the project. It also included a revision and analyses of a scarce existent bibliography and reports and evaluations of both. / O presente estudo trata de duas propostas-piloto que est?o sendo desenvolvidas em ?reas de reserva extrativista (RESEX), visando ao seu desenvolvimento sustent?vel. Considera-se que a constru??o desse tipo de alternativa para as popula??es agroextrativistas da regi?o representa um desafio. O objetivo principal foi caracterizar, analisar e compreender os significados pol?ticos, econ?micos, culturais e sociais de dois projetos: Manejo Florestal de Uso M?ltiplo do PAE Porto Dias e Ilhas de Alta Produtividade Racionaliza??o da Extra??o Gum?fera em ?reas Extrativistas . O estudo das duas propostas se faz a partir das an?lises da situa??o da explora??o madeireira na regi?o amaz?nica e do contexto social e pol?tico acreano, em particular o que se abre com a elei??o de representantes do movimento popular para o governo do Estado. Sua an?lise pode ser um passo adiante no desenvolvimento desses projetos, que visam ? melhoria das condi??es de vida dos trabalhadores extrativistas sem esquecer a quest?o ambiental. Acreditamos na alternativa do neoextrativismo, que o projeto IAPs defende, por ter um car?ter participativo, fortalecer a cultura do seringueiro e acenar para uma perspectiva de viabilidade econ?mica, ao mesmo tempo em que recupera ?reas devastadas e respeita a biodiversidade da floresta. A metodologia utilizada deu a devida import?ncia ao trabalho de campo, durante o qual foram feitas entrevistas e levantados dados secund?rios junto aos principais atores envolvidos direta ou indiretamente com os projetos. Incluiu, tamb?m, revis?o e an?lise da escassa bibliografia existente e de relat?rios e avalia??es sobre ambos.

I investigated oribatid mite assemblages in a beech-maple forest in southwestern Quebec. I first examined the effects of four forest stand types (American Beech (Fagus grandifolia) dominated, Sugar Maple (Acer saccharum) dominated, mixed deciduous and coniferous plantations) and three open site types (agricultural field, fallow pasture and unmanaged hay field) in structuring oribatid mite assemblages. My second study focused on the effects of changes in litter depth (a factor that varies by stand type) on the structure of oribatid assemblages. / Stand type was shown to be an important factor in determining oribatid mite abundances, species richness and assemblage composition. Results from the second study confirm this, but revealed no effect of changes in litter depth on oribatid mite assemblages. These findings serve to demonstrate that while examining specific environmental factors as determinants of oribatid mite diversity and distribution is important, more general factors such as habitat type cannot be ignored.

Thesis (doctoral)--Swedish University of Agricultural Sciences, 2007. / Thesis documentation sheet inserted. Includes appendix of four papers and manuscripts, three co-authored with others. Includes bibliographical references. Also issued electronically via World Wide Web in PDF format; online version lacks appendix.

No description available.

A Mata Atlântica (MA) é um dos ambientes naturais mais ameaçados do Brasil, tendo sua área original atualmente bastante reduzida pelas ações antrópicas. As atividades agrícolas estão incluídas entre os fatores de impacto a este Bioma; e inserida na área de domínio da MA está a região de Apiaí - SP, produtora de tomate (Solanum lycopersicum L.) de mesa, uma cultura caracterizada pela sua importância alimentar, e responsável por significativos impactos socioambientais devido ao uso de agroquímicos, desmatamentos e más condições de trabalho. Devido à infestação por insetos-praga e às ocorrências de doenças agrícolas, esta cultura é considerada uma das mais exigentes em tratos culturais necessitando pulverizações constantes e uso geral de agroquímicos. Este trabalho busca ampliar o conhecimento sobre as funções que a biodiversidade florestal pode ter como um instrumento para auxiliar o manejo agrícola de insetos fitófagos e doenças em cultivos de tomate de mesa. No município de Apiai - SP, entre 2008 e 2010, foram instalados 5 módulos experimentais de cultivo de tomate em manejo agroecológico no modelo de Ilhas de Alta Produtividade (IAPs), em locais onde a biodiversidade florestal é um elemento presente no entorno. Em cada módulo de cultivo, foram analisados: a biodiversidade florestal no entorno até uma distância de 300 m nos sentidos N, S, L, O; a ocorrência de insetos-praga e doenças agrícolas e a viabilidade econômica e socioambiental. Os resultados foram comparados aos mesmos dados coletados de outros 5 cultivos convencionais da mesma região ecológica, que cultivaram variedades semelhantes, no mesmo período, em ambientes com menor biodiversidade florestal nativa em seu entorno. Os módulos experimentais de cultivo agroecológico demonstraram uma área media de cobertura Florestal Atlântica em torno de 43,82%%, com uma ocorrência media de 46 espécies arbóreas nativas com Índice de Biodiversidade Florestal de 3,87; os cultivos comparativos apresentaram áreas médias de cobertura florestal em seu entorno de 31,34 %, com uma ocorrência de 26 espécies arbóreas nativas e índice de biodiversidade florestal de 3,44. Em amostras de 20 plantas de tomate por cultivo, nas áreas experimentais, não foram identificadas a ocorrência de viroses, uma única espécies causadora de doença fúngica e um total de 4 espécies de insetos-praga foram identificadas. Os produtores convencionais comparados tiveram a ocorrência de 11 espécies de doenças fúngicas e bacterianas, com 7% de ocorrência de viroses e 7 espécies de insetos fitófagos. Os dados mostraram que existe relação da biodiversidade florestal com o número de espécies de insetos-praga nos cultivos. Em uma análise de viabilidade socioambiental entre os cultivos experimentais e comparativos, foi identificada uma maior taxa de risco, investimento, produtividade, volume de produção, e prejuízos financeiros, bem como maiores impactos ambientais e sociais entre os cultivos de tomate convencionais comparativos. Os modelos experimentais com biodiversidade florestal em seu entorno se mostraram viáveis social e ambientalmente para utilização prática na agricultura familiar na região de Apiai - SP. / The neotropical Atlantic Rain Forest (MA) is one of the most threatened natural environments of Brazil, with its original area now greatly reduced by human actions. Agricultural activities are included among the impact factors in this biome, and inserted in the area with the MA is the region of Apiaí - SP producer of tomato (Solanum lycopersicum L.) table, a culture characterized by its nutritional importance and also responsible for significant environmental impacts due to the use of agrochemicals, deforestation and poor working conditions. Due to infestation by insect pests and plant diseases this crop is considered one of the most demanding in cultivation requirements such as constant spraying and general use of agrochemicals. This work seeks to expand the knowledge about the functions that forest biodiversity can perform as a tool to assist the cultivation control in the control of phytophagous insects and diseases in tomato crop. In the district of Apiaí - SP, from 2008 to 2010, five modules have been installed for experimental cultivation of tomato in the agroecologic model called Islands of High Productivity (IAPs), in places where forest biodiversity is an element current around. The biodiversity in the surrounding forest to a distance of 300 m in the directions N, S, E, W, the occurrence of insect pests and diseases and also the economic viability and environmental impact were analyzed in each module of cultivation. The results were compared to the same data collected from five other conventional crops in the same ecological region which cultivated similar varieties in the same period in environments with less native forest biodiversity in their environment. The experimental agroecologic modules showed an average area of Atlantic Forest cover around 43.82%, with an average occurrence of 46 native tree species and forest biodiversity indices of 3.87; the conventional modules had 31.34% of atlantic forest cover, with an occurrence of 26 native tree species and forest biodiversity indices of 3.44. In the experimental areas, with sampling of 20 tomato plants/ cultivation, were not identified any occurrence of viruses but only a single species causing fungal disease and a total of four species of insect pests. The conventional producers had the occurrence of 11 species of fungal and bacterial diseases, with 7% occurrence of viruses and 7 species of phytophagous insects. The data showed that there are relationship of forest biodiversity and number of species of insect pests in crops. In analysis of economic and socio-environmental viabilities between the experimental and comparative cultivations, it was identified a higher rate of risk, investment, productivity, production volume and financial losses, as well as higher environmental and social impacts of the conventional tomato cultivations. The agroecologic experimental models with higher forest biodiversity around have proved being socially and environmentally viable for practical use in family farming in the region of Apiai - SP.

Climate change is expected to drastically change the environmental conditions which forests depend. Lags in tree species movements will likely be outpaced by a more rapidly changing climate. This may result in species extirpation, a change in forest structure, and a decline in resistance and resilience (i.e., the ability to persist and recover from external perturbations, respectively). In the northern Great Lakes region of North America, an ecotone exists along the boreal-temperate transition zone where large changes in species composition exist across a climate gradient. Increasing temperatures are observed in the more southern landscapes. As climate change is expected to substantially affect mid-continental landscapes, this region is especially vulnerable to climate change. My research assessed the effects of climate change under business as usual (BAU) management as well as alternative management strategies. To do so, I simulated forest change in two landscapes (northeastern Minnesota and northern lower Michigan) under three climate change scenarios (current climate, low emissions, and high emissions), and four management scenarios (BAU, modified silviculture, expanded reserves, and climate suitable planting) with a spatially-explicit forest simulation model from year 2000 to year 2150. Specifically, I explored how climate change would affect relationships between tree species diversity and productivity; how expanded reserves and modified silviculture may affect aboveground biomass (AGB) and species diversity; how climate suitable planting may affect functional diversity, and AGB; and how alternative management may affect the resistance and resilience of forests to multiple disturbances interacting with climate change. Under the BAU management scenario, I found that current and low emissions climate scenarios did not affect the relationship between species diversity and productivity; however, under a high emissions climate scenario, a decline in simulated productivity was coupled with a stronger positive relationship between diversity and productivity. Under the high emissions climate scenario, overall productivity declined in both landscapes with specific species declines projected for boreal species such as balsam fir (Abies balsamea) and black spruce (Picea mariana). Under alternative management scenarios, I simulated a limited ability to increase tree species and functional diversity, AGB, and net primary productivity under climate change. The limits of management were especially apparent under the high emissions climate scenario. In a novel approach to measuring resilience, I plotted the recovery of both initial species composition and AGB to stochastic fire events for each simulation. This approach assessed both a general response (i.e. AGB) with a more specific response (i.e. species composition). My results suggest that climate change will reduce the resilience of northern Great Lake forest AGB and species composition and that management effects will be largely outweighed by the declines expected due to climate change. My results highlight the necessity to consider even more innovative and creative solutions under climate change (e.g., planting species from even further south than I simulated).

One of the human activities impacting biodiversity is the cutting of old-growth forests. In response to the controversy surrounding the cutting of old-growth in the coastal rainforest of BC, the Ministries of the Environment and Forests have produced biodiversity guidelines that are to be applied when manipulating stands in the provincial forest. This study augments these guidelines by investigating the diversity differences between second-growth and old-growth forests in relation to site quality. We demonstrate how standlevel plant diversity differs between 40-year-old and old-growth stands in the Very Wet Coastal Western Hemlock subzone (CWHvm) on Vancouver Island. This information is intended to provide foresters with an understanding of the effects of age, disturbance and site quality on stand-level plant diversity, thereby allowing for informed professional management decisions.