Thesis (M.S.)--Oregon State University, 2007. / Printout. Includes bibliographical references. Also available on the World Wide Web.

Nutrient cycles and budgets have been calculated for various ecosystems, but the impact of floral and bark litter decomposition on nutrient cycling has been little investigated. In this study, the characteristics and decomposition of floral and bark litter produced by Nothofagus fusca in the Lewis Pass Reserve, New Zealand, was investigated, using both field and laboratory studies. Nothofagus fusca floral litter production in 1999 was 734 ± 76 kg ha⁻¹. Floral production in 2000 was estimated to be approximately 1% of this mass, the considerable difference being due to mast flowering in 1999. The decay rate constant, k, for floral litter in the field was 0.94 ± 0.01, and mass loss after one year was estimated to be 61%. The input of nitrogen to the litter layer in Nothofagus fusca floral litter was 12 ± 1 kg ha⁻¹, and it was estimated that 65% of this nitrogen was released from the floral litter in the one year. Phosphorous input to the litter layer through Nothofagus fusca floral litter in 1999 was 0.8 ± 0.1 kg ha⁻¹, of which 69% was released in one year. It was estimated that in 1999 nitrogen and phosphorous inputs to the litter layer through Nothofagus fusca floral litter were 117% and 73% respectively of that through foliar litter. Four types of Nothofagus fusca bark were identified and further differences between bark types were confirmed by chemical analysis. Inner bark contained less nitrogen than outer bark, and was slower to decompose in microcosms, contradicting the findings of other research. Annual nitrogen and phosphorous inputs through the production of all types of Nothofagus fusca bark litter was estimated to be 1.0 kg ha⁻¹ and 0.2 kg ha⁻¹ respectively, although confidence in these values was low. Significant proportions of the nitrogen and phosphorous content in bark were water soluble. Field and laboratory experiments indicated net nitrogen immobilisation occurred in all bark litter types after one year in the field, while net release of phosphorous occurred after one year.

4 pp. / DeGomez, T. 2006. Preventing Bark Beetle Attacks on Conifers with Insecticides. University of Arizona, College of Agriculture and Life Sciences Bulletin, AZ1380. Tucson, Arizona. / A common method of protecting individual trees from bark beetle attack in the western U.S. is to saturate the tree bole with carbaryl using a hydraulic sprayer at high pressure. With this type of application method spray deposition will occur off-target and may contact open waters where sensitive species are subject to the toxic effects of the pesticide. We report on a recent study in which the authors reported carbaryl drift resulting from single tree protection treatments poses little threat to adjacent aquatic environments, a primary concern when treating trees in campgrounds in the Western United States. Using reasonable no-spray buffers will ensure that adjacent aquatic environments are protected from any negative impacts.

Tjugoåtta leveranser av biobränsle, bestående av grot, bark och städbark har fukthaltbestämts med en noggrannare metod än den metod som idag används vid Djuped kraftvärmeverk i Hudiksvall, detta för att kartlägga hur exakta fukthaltsmätningarna idag är. Som de flesta andra Kraftvärmeverk i Sverige använder Djuped vikt och fukthalt för beräkningar av energiinnehåll i bränslen, denna är sedan underlag för betalningar till leverantörer av biobränsle. Den testfuktmätning som användes för att bestämma en noggrannare fukthalt vid Djuped bestod av sex gånger större prov än de som idag används, dessa visade tydligt att individuella leveranser av biobränsle kan variera i fukthalt med upp till 6,8 % och att systematiska samt slumpmässiga fel kan förekomma. En lösning på dessa problem är att informera de berörda parterna om hur viktiga noggranna fukthaltmätningar måste vara samt att införa en ny typ av manuell provtagning, som förhoppningsvis eliminerar några av de slumpmässiga felen. Den nya metoden består av sju till åtta gånger större prover jämfört med den idag rutinmässiga fuktprovtagningen och bör öka noggrannheten vid fuktmätning avsevärt. Denna moderniserade metod använder sig av plasthinkar med lufttäta lock istället för plastpåsar, som har visat sig var opålitliga då dessa kan gå sönder eller ligga öppna vid mellanlagring. Atutomatiserade testannordningar för mätning av fukthalt har visat sig fungera snabbt och effektivt men är fortfarande inte tillräckligt utvecklade för att implementeras vid Djupeds kraftvärmeverk i dagsläget. Dessutom bör nya avtal skrivas med leverantörer av biobränsle. Dessa avtal skall involvera energiberäkningar som tar hänsyn till den energi som krävs för de fasförändringar som genomgås vid uppvärmning av den snö och is som kan förekomma i bränslelass under vintertid.

No description available.

Nutrient cycles and budgets have been calculated for various ecosystems, but the impact of floral and bark litter decomposition on nutrient cycling has been little investigated. In this study, the characteristics and decomposition of floral and bark litter produced by Nothofagus fusca in the Lewis Pass Reserve, New Zealand, was investigated, using both field and laboratory studies. Nothofagus fusca floral litter production in 1999 was 734 ± 76 kg ha⁻¹. Floral production in 2000 was estimated to be approximately 1% of this mass, the considerable difference being due to mast flowering in 1999. The decay rate constant, k, for floral litter in the field was 0.94 ± 0.01, and mass loss after one year was estimated to be 61%. The input of nitrogen to the litter layer in Nothofagus fusca floral litter was 12 ± 1 kg ha⁻¹, and it was estimated that 65% of this nitrogen was released from the floral litter in the one year. Phosphorous input to the litter layer through Nothofagus fusca floral litter in 1999 was 0.8 ± 0.1 kg ha⁻¹, of which 69% was released in one year. It was estimated that in 1999 nitrogen and phosphorous inputs to the litter layer through Nothofagus fusca floral litter were 117% and 73% respectively of that through foliar litter. Four types of Nothofagus fusca bark were identified and further differences between bark types were confirmed by chemical analysis. Inner bark contained less nitrogen than outer bark, and was slower to decompose in microcosms, contradicting the findings of other research. Annual nitrogen and phosphorous inputs through the production of all types of Nothofagus fusca bark litter was estimated to be 1.0 kg ha⁻¹ and 0.2 kg ha⁻¹ respectively, although confidence in these values was low. Significant proportions of the nitrogen and phosphorous content in bark were water soluble. Field and laboratory experiments indicated net nitrogen immobilisation occurred in all bark litter types after one year in the field, while net release of phosphorous occurred after one year.

Thesis (M. Ag. Sci.)--University of Adelaide, Dept. of Entomology, 1966. / Includes bibliographical references.

Thesis (M.S.)--University of Wisconsin--Madison, 1982. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 133-134).

No description available.

Orientador: Carmen Regina Marcati / Resumo: A casca é um sistema biológico complexo que desempenha diversas funções na planta, incluindo condução de fotoassimilados, suporte mecânico, armazenamento de substâncias e proteção contra herbívoros, patógenos e intempéries como o fogo. A casca é composta, principalmente, pelo floema secundário e pela periderme, e reveste tanto caules quanto raízes. O caule está exposto à atmosfera e tem funções de elevação e suporte da planta, enquanto a raiz está exposta ao solo e tem funções de fixar a planta ao solo, armazenar substâncias e absorver e conduzir água e nutrientes. Contudo, pouco se sabe se as diferentes funções de caules e raízes indicam diferentes funções na casca de cada órgão. Neste trabalho, comparamos a casca de caules e raízes de 15 espécies representativas do cerrado paulista e testamos se a casca do caule apresentaria funções de suporte e proteção, enquanto a casca da raiz apresentaria função de armazenamento de substâncias. Também testamos se encontraríamos maior eficiência na condução de fotoassimilados na casca da raiz. Para tanto, selecionamos 15 espécies de árvores e arbustos do cerrado sensu stricto e amostramos a casca do caule e da raiz. Analisamos a estrutura (espessura e anatomia), a densidade e a química (água, açúcares solúveis, amido, nitrogênio, fósforo e carbono) e relacionamos com as funções da casca em cada órgão. Na casca do caule, encontramos maior espessura da periderme, devido ao felema mais largo com células maiores e mais espessas, e menor dens... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Bark is a complex biological system that performs multiple functions in plant, including photoassimilates conduction, mechanical support, storage and protection against herbivores, pathogens and fire. Bark comprises mainly the secondary phloem and the periderm, and covers both trunks and roots. The trunk is exposed to the atmosphere and has the main functions of plant elevation and plant support, whereas the root is exposed to the ground and has the main functions of fix the plant to the ground, store substances, provide water and nutrients to the plant. However, remain unclear whether the different functions of trunk s and roots indicate different functions in the bark of each organ. In this work, we compared the bark of trunk and roots of species in the cerrado of São Paulo, tested whether the trunk bark presents both support and protection functions, whereas the root bark presents storage function. We also tested whether we would find higher efficiency of photoassimilates conduction in the root bark. For this purpose, we selected 15 representative species of trees and shrubs in the cerrado sensu stricto and sample both trunk and root barks. We analyzed the structure (thickness and anatomy), density and chemistry (water, soluble sugars, starch, nitrogen, phosphorus and carbon) and associated to the bark functions in each organ. In the trunk bark, we found thicker periderm, due to thicker phellem with larger cell and thicker wall cells, and lower periderm density, suggesting... (Complete abstract click electronic access below) / Doutor