Sargassum fluitans and natans, types of brown algae, wash up on Galveston Island, Texas annually from May to August. Sargassum smells bad, hurts tourism and impairs sea turtle hatchings. Coastal managers are confronted with the difficult choice of cleaning Sargassum off the beach or leaving it alone. The current beach management practice is to rake the algae with tractors and deposit it at the base of the dunes. The environmental impacts of raking and ecological benefits of Sargassum are unknown. The Galveston Island Park Board of Trustees (GIPBT) used to rake all beaches under their management before Hurricane Alicia in 1983. Then, citizens started to complain that raking was causing erosion. Now, there are people who argue for both raking and leaving the beach alone. Environmental policies require complex decisions that take into consideration social, economical, ecological, and cultural values. The GIPBT initiated the Sargassum Policy Committee to gain knowledge of different stakeholder values and scientific research to develop beach management. The first study analyzed elevation changes over a year period on raked and unraked beaches on both the West and East end of Galveston Island. The Analysis ofVariance results indicated that there is not a difference in elevation changes between the raked and unraked beaches over a year.The second study analyzed the effects of Sargassum on the dune plant Panicum amarum. Plants were asexually grown in a greenhouse in sand without (control) and with Sargassum. The effects of small versus large amounts, top versus mixed with sand and washed versus unwashed Sargassum were tested. The results indicated that the addition of Sargassum increased plant growth. The treatments with large amounts of Sargassum and unwashed treatments showed significant growth changes at the 95% confidence level. The last component analyzed the collaborative potential of the Sargassum Policy Committee through observations of meetings and surveys of the members. Daniel and Walker’s Progressive Triangle was used to assess the relationship, procedural and substance dimensions of collaborative learning. Then, suggestions were made for increasing collaboration. The combination of scientific research and stakeholder values has resulted in the creation of sound beach management.

Sargassum fluitans and natans, types of brown algae, wash up on Galveston Island, Texas annually from May to August. Sargassum smells bad, hurts tourism and impairs sea turtle hatchings. Coastal managers are confronted with the difficult choice of cleaning Sargassum off the beach or leaving it alone. The current beach management practice is to rake the algae with tractors and deposit it at the base of the dunes. The environmental impacts of raking and ecological benefits of Sargassum are unknown. The Galveston Island Park Board of Trustees (GIPBT) used to rake all beaches under their management before Hurricane Alicia in 1983. Then, citizens started to complain that raking was causing erosion. Now, there are people who argue for both raking and leaving the beach alone. Environmental policies require complex decisions that take into consideration social, economical, ecological, and cultural values. The GIPBT initiated the Sargassum Policy Committee to gain knowledge of different stakeholder values and scientific research to develop beach management. The first study analyzed elevation changes over a year period on raked and unraked beaches on both the West and East end of Galveston Island. The Analysis ofVariance results indicated that there is not a difference in elevation changes between the raked and unraked beaches over a year.The second study analyzed the effects of Sargassum on the dune plant Panicum amarum. Plants were asexually grown in a greenhouse in sand without (control) and with Sargassum. The effects of small versus large amounts, top versus mixed with sand and washed versus unwashed Sargassum were tested. The results indicated that the addition of Sargassum increased plant growth. The treatments with large amounts of Sargassum and unwashed treatments showed significant growth changes at the 95% confidence level. The last component analyzed the collaborative potential of the Sargassum Policy Committee through observations of meetings and surveys of the members. Daniel and Walker’s Progressive Triangle was used to assess the relationship, procedural and substance dimensions of collaborative learning. Then, suggestions were made for increasing collaboration. The combination of scientific research and stakeholder values has resulted in the creation of sound beach management.

Exit polls have had a hard time predicting election results in Sweden over the last decade. The introduction of the Sweden Democrats in the political scene has generally caused problems for polling organizations. Opinion polls have a big influence on the economic market and therefore any wrongdoing might cause a big disturbance in the economy. This paper develops a model based on systematic sampling differences and sociodemographic background variables in order to predict the results of the Swedish general election 2018. The study uses data from SVT´s exit poll and SCB´s voter turnout survey. The results of the study show that the model in general predicts the 2018 Swedish general election better than the prognosis of SVT.

The usage of crop residues, among other lignocellulosic biomass, has being considered a promising alternative feedstock for bioenergy (i.e., second generation ethanol - ethanol 2G and bioelectricity) production. With the adoption of sugarcane-mechanical harvesting in Brazil, in average 15 Mg ha-1 of straw are left on the field annually. Partial straw removal for bioenergy production has become a common practice, while partial straw retention on the field ensures several benefits for the soil-plant system. Efforts have being done in order to establish the best route to straw recovery from the field and defining the amount which meeting both needs. Thus, the aims of this study were: i) to establish a step-by-step guidelines to straw recovery from the field; ii) to determine the implications of increasing rates of straw removal on plant growth, stalk yield and stalk industrial quality; iii) to evaluate the effectiveness of straw-blanket raking practice on plant growth and yield, and iv) to use Soil Management Assessment Framework (SMAF) as a tool to perform an integrated approach of soil quality (SQ) under different rates of straw removal. To achieve the proposed goals, a 2-years experiment was set up within the dry and wet seasons at Valparaíso and Capivari, São Paulo, locations with different edaphoclimatic conditions. Increases of primary extractor fan\'s velocity on the harvester lead to placement and removal of straw rates proportionally to 0, 25, 50, 75 e 100%. After two years, parameters associated to the soil- chemical [(Phosphorus-P, Potassium-K and pH), physical-(bulk density) and biological- (microbial biomass carbon-MBC and SOC)] attributes were analyzed within the 0-5, 5-10, 10-20 and 20-30 cm. Under colder climatic condition, plant tillering improved by the increasing rates of straw removal, however plant growth and stalk yield are slightly affected by the straw management. Stalk harvested in the dry season presented higher industrial quality than those harvested within the wet season but this parameter is unaffected by straw removal. Further, under colder climatic condition, to rake the straw blanket enhanced plant tillering while plant growth and stalk yield were not influenced by raking the straw blanket. No straw removal increases P content on plant tissue, regardless of blanket management, especially under the poorest inherent soil condition. The SMAF tool was able to detect changes on soil quality under different rates of straw removal and Oxisol responds faster to straw removal management than Ultisol in the short term. Total straw removal leaded to Oxisoil physical quality degradation; among the soil attributes, soil-physical attribute within the 0-10 cm is correlated with stalk yield. The partial straw removal for bioenergy production leads to the optimization on sugarcane biomass usage. However, the appropriate rate of straw to be removed is site specific and ranged 4-9 Mg ha-1 under the conditions in which this study was performed. The stalk yield was unaffected by raking the straw blanket. The monitoring of SOC, adoption of traffic controller and application of subproducts from the sugarcane industry are strategies to increase soil quality and, consequently, the sustainability of the crop cultivation. / O uso de resíduos culturais, dentre outros tipos de biomassa lignocelulósica, tem sido considerado uma alternativa promissora para produção de bioenergia (etanol de segunda geração e bioeletricidade). Com a implementação da colheita mecanizada da cana-de-açúcar no Brasil, em média 15 Mg ha-1 palha são deixadas no campo anualmente. A utilização de parte deste resíduo para produção de bioenergia tem se tornado uma prática comum, enquanto a manutenção de parte da palha no campo viabiliza vários benefícios ao sistema solo-planta. Esforços têm sido feitos a fim de estabelecer a melhor rota para remoção da palha do campo e definir a quantidade que atenda ambas demandas. Assim, os objetivos deste estudo foram: i) estabelecer um guia que viabilize a remoção de diferentes taxas de palha; ii) determinar as implicações oriundas da remoção de taxas de palha no crescimento, produtividade e qualidade tecnológica de colmos; iii) avaliar a eficácia do enleiramento da camada de palha sobre o crescimento e produtividade da cultura e, iv) utilizar Soil Management Assessment Framework (SMAF) como ferramenta para avaliar de modo integrado os efeitos da remoção de diferentes taxas de remoção de palha sobre a qualidade do solo (QS). Para tanto, foram conduzidos quatro ensaios, sendo um na estação seca e outro na estação úmida em dois locais: Capivarí e Valparaíso, SP; locais com diferentes condições edafoclimáticas. Crescentes rotações no extrator primário da colhedora viabilizaram a deposição e remoção de taxas de palha proporcionais a 0, 25, 50, 75 e 100%. Após dois anos, análises de parâmetros associados aos atributos químicos [(P, K, pH), físicos (densidade) e biológicos (carbono da biomassa microbiana - MBC e SOC)] do solo foram realizadas nas profundidades 0- 5, 5-10, 10-20 e 20-30 cm. Em condições climática mais fria, a remoção de crescentes quantidades de palha melhora o perfilhamento da cultura; entretanto, o crescimento e produtividade de colmo são pouco afetadas pelo manejo da palha. A qualidade tecnológica de colmos colhidos na época seca é superior aos colhidos na época úmida, entretanto, este parâmetro não é afetado pela remoção de crescentes quantidades de palha. Sobre condições climática mais fria, o perfilhamento é beneficiado pelo enleiramento da palha, ao passo que tanto o crescimento quanto a produtividade são insensíveis à essa prática. A retenção da palha aumenta o conteúdo de P no tecido vegetal, especialmente em solo naturalmente pouco fértil. A SMAF foi capaz de detectar alterações na QS em função da remoção de taxas de palha; sendo o Latossolo Vermelho distrófico típico o mais afetado pela remoção da palha em relação ao Argissolo Vermelho- Amarelo distrófico típico em curto prazo. A remoção total da palha promoveu degradação física do primeiro tipo de solo; dentre os atributos do solo avaliados, o atributo físico na profundidade 0-10 cm está correlacionado com a produtividade da cultura. A remoção parcial da palha de canade- açúcar para produção de bioenergia promove otimização no uso da biomassa da cultura. Entretanto, a taxa de palha a ser removida é intrínseca para cada local e variou de 4-9 Mg ha-1 neste estudo. A produtividade é insensível ao enleiramento da palha. O monitoramento nos teores de carbono do solo, a adoção do controle de tráfego de máquinas e a aplicação de resíduos da agroindústria canavieira podem ser estratégias adotadas para melhorar a QS e, por consequência, a sustentabilidade de cultivo da cana-de-açúcar.

The usage of crop residues, among other lignocellulosic biomass, has being considered a promising alternative feedstock for bioenergy (i.e., second generation ethanol - ethanol 2G and bioelectricity) production. With the adoption of sugarcane-mechanical harvesting in Brazil, in average 15 Mg ha-1 of straw are left on the field annually. Partial straw removal for bioenergy production has become a common practice, while partial straw retention on the field ensures several benefits for the soil-plant system. Efforts have being done in order to establish the best route to straw recovery from the field and defining the amount which meeting both needs. Thus, the aims of this study were: i) to establish a step-by-step guidelines to straw recovery from the field; ii) to determine the implications of increasing rates of straw removal on plant growth, stalk yield and stalk industrial quality; iii) to evaluate the effectiveness of straw-blanket raking practice on plant growth and yield, and iv) to use Soil Management Assessment Framework (SMAF) as a tool to perform an integrated approach of soil quality (SQ) under different rates of straw removal. To achieve the proposed goals, a 2-years experiment was set up within the dry and wet seasons at Valparaíso and Capivari, São Paulo, locations with different edaphoclimatic conditions. Increases of primary extractor fan\'s velocity on the harvester lead to placement and removal of straw rates proportionally to 0, 25, 50, 75 e 100%. After two years, parameters associated to the soil- chemical [(Phosphorus-P, Potassium-K and pH), physical-(bulk density) and biological- (microbial biomass carbon-MBC and SOC)] attributes were analyzed within the 0-5, 5-10, 10-20 and 20-30 cm. Under colder climatic condition, plant tillering improved by the increasing rates of straw removal, however plant growth and stalk yield are slightly affected by the straw management. Stalk harvested in the dry season presented higher industrial quality than those harvested within the wet season but this parameter is unaffected by straw removal. Further, under colder climatic condition, to rake the straw blanket enhanced plant tillering while plant growth and stalk yield were not influenced by raking the straw blanket. No straw removal increases P content on plant tissue, regardless of blanket management, especially under the poorest inherent soil condition. The SMAF tool was able to detect changes on soil quality under different rates of straw removal and Oxisol responds faster to straw removal management than Ultisol in the short term. Total straw removal leaded to Oxisoil physical quality degradation; among the soil attributes, soil-physical attribute within the 0-10 cm is correlated with stalk yield. The partial straw removal for bioenergy production leads to the optimization on sugarcane biomass usage. However, the appropriate rate of straw to be removed is site specific and ranged 4-9 Mg ha-1 under the conditions in which this study was performed. The stalk yield was unaffected by raking the straw blanket. The monitoring of SOC, adoption of traffic controller and application of subproducts from the sugarcane industry are strategies to increase soil quality and, consequently, the sustainability of the crop cultivation. / O uso de resíduos culturais, dentre outros tipos de biomassa lignocelulósica, tem sido considerado uma alternativa promissora para produção de bioenergia (etanol de segunda geração e bioeletricidade). Com a implementação da colheita mecanizada da cana-de-açúcar no Brasil, em média 15 Mg ha-1 palha são deixadas no campo anualmente. A utilização de parte deste resíduo para produção de bioenergia tem se tornado uma prática comum, enquanto a manutenção de parte da palha no campo viabiliza vários benefícios ao sistema solo-planta. Esforços têm sido feitos a fim de estabelecer a melhor rota para remoção da palha do campo e definir a quantidade que atenda ambas demandas. Assim, os objetivos deste estudo foram: i) estabelecer um guia que viabilize a remoção de diferentes taxas de palha; ii) determinar as implicações oriundas da remoção de taxas de palha no crescimento, produtividade e qualidade tecnológica de colmos; iii) avaliar a eficácia do enleiramento da camada de palha sobre o crescimento e produtividade da cultura e, iv) utilizar Soil Management Assessment Framework (SMAF) como ferramenta para avaliar de modo integrado os efeitos da remoção de diferentes taxas de remoção de palha sobre a qualidade do solo (QS). Para tanto, foram conduzidos quatro ensaios, sendo um na estação seca e outro na estação úmida em dois locais: Capivarí e Valparaíso, SP; locais com diferentes condições edafoclimáticas. Crescentes rotações no extrator primário da colhedora viabilizaram a deposição e remoção de taxas de palha proporcionais a 0, 25, 50, 75 e 100%. Após dois anos, análises de parâmetros associados aos atributos químicos [(P, K, pH), físicos (densidade) e biológicos (carbono da biomassa microbiana - MBC e SOC)] do solo foram realizadas nas profundidades 0- 5, 5-10, 10-20 e 20-30 cm. Em condições climática mais fria, a remoção de crescentes quantidades de palha melhora o perfilhamento da cultura; entretanto, o crescimento e produtividade de colmo são pouco afetadas pelo manejo da palha. A qualidade tecnológica de colmos colhidos na época seca é superior aos colhidos na época úmida, entretanto, este parâmetro não é afetado pela remoção de crescentes quantidades de palha. Sobre condições climática mais fria, o perfilhamento é beneficiado pelo enleiramento da palha, ao passo que tanto o crescimento quanto a produtividade são insensíveis à essa prática. A retenção da palha aumenta o conteúdo de P no tecido vegetal, especialmente em solo naturalmente pouco fértil. A SMAF foi capaz de detectar alterações na QS em função da remoção de taxas de palha; sendo o Latossolo Vermelho distrófico típico o mais afetado pela remoção da palha em relação ao Argissolo Vermelho- Amarelo distrófico típico em curto prazo. A remoção total da palha promoveu degradação física do primeiro tipo de solo; dentre os atributos do solo avaliados, o atributo físico na profundidade 0-10 cm está correlacionado com a produtividade da cultura. A remoção parcial da palha de canade- açúcar para produção de bioenergia promove otimização no uso da biomassa da cultura. Entretanto, a taxa de palha a ser removida é intrínseca para cada local e variou de 4-9 Mg ha-1 neste estudo. A produtividade é insensível ao enleiramento da palha. O monitoramento nos teores de carbono do solo, a adoção do controle de tráfego de máquinas e a aplicação de resíduos da agroindústria canavieira podem ser estratégias adotadas para melhorar a QS e, por consequência, a sustentabilidade de cultivo da cana-de-açúcar.

The aim of my study is to determine the influence of historical management practices on the camposition of vascular species in hilly country forests on the Vysoká stráň hill in the Bohemian Karst Protected Landscape Area in the Czech Republic. My thesis is divided into two parts. The first part of my thesis describes influences of forest management on the herb diversity from different scientific studies. There is some information about the influence of herbivorous grazing, pollarding, litter raking and fire. Secondly provides a case study dealing with the influence of historical management on the vascular species composition in the forest understory. My experimental area was divided into 32 treatments, where three different ways of historical management were used - mowing of the understory vegetation, litter raking and the combination of mowing and litter raking. The fourth area was a control treatment. Change in the herb diversity depending on a time is statistically significant but changes in the herb diversity depending on different ways of historical management are statistically insignificant. We detected a distinct decline in the herb diversity during our experiment, also on the control treatments. The main gradient of vegetation points from mesophilous acidophytes to species characteristic...

在本論文中，根據所建立的100,000筆模擬資料作為抽樣的母體，利用簡單隨機抽樣法（simple random sampling；SRS）從此模擬的資料中共抽出1068筆成功樣本，分別考慮了當個案訪問失敗（unit nonresponse）情形發生時是『隨機性』及『非隨機性』兩種情況下比較(1)事後分層加權（poststratification approach）；(2)多個變數反覆加權（raking or raking ratio）；及(3)估計成功率加權等三種加權方法之效果如何。 當訪問失敗具完全隨機性的情況之下所抽出之樣本，由於原始樣本的代表性過於『完美』，即使是經過事後分層加權或是raking加權後，均無顯著的效果。因此，對於樣本的改善程度實在是微不足道！而在訪問失敗是非隨機性的情況時，事後分層加權對於變數間具較強相關性時，則具有較佳的加權效果；raking加權方式的加權效果普遍上均不錯的表現，值得廣泛地採用；而估計成功率加權的效果則必須取決於估計準確與否，否則可能由於估計的偏差而導致加權效果不彰。 最後，本文亦提供了事後分層加權及raking加權的適用時機及建議，以作為日後從事抽樣調查工作者的參考意見。

Non-response is an error common to most surveys. In this dissertation, the error of non-response is described in terms of its sources and its contribution to the Mean Square Error of survey estimates. Various response and completion rates are defined. Techniques are examined that can be used to identify the extent of nonresponse bias in surveys. Methods to identify auxiliary variables for use in nonresponse adjustment procedures are described. Strategies for dealing with nonresponse are classified into two types, namely preventive strategies and post hoc adjustments of data. Preventive strategies discussed include the use of call-backs and follow-ups and the selection of a probability sub-sample of non-respondents for intensive follow-ups. Post hoc adjustments discussed include population and sample weighting adjustments and raking ratio estimation to compensate for unit non-response as well as various imputation methods to compensate for item non-response. / Mathematical Sciences / M. Com. (Statistics)

Non-response is an error common to most surveys. In this dissertation, the error of non-response is described in terms of its sources and its contribution to the Mean Square Error of survey estimates. Various response and completion rates are defined. Techniques are examined that can be used to identify the extent of nonresponse bias in surveys. Methods to identify auxiliary variables for use in nonresponse adjustment procedures are described. Strategies for dealing with nonresponse are classified into two types, namely preventive strategies and post hoc adjustments of data. Preventive strategies discussed include the use of call-backs and follow-ups and the selection of a probability sub-sample of non-respondents for intensive follow-ups. Post hoc adjustments discussed include population and sample weighting adjustments and raking ratio estimation to compensate for unit non-response as well as various imputation methods to compensate for item non-response. / Mathematical Sciences / M. Com. (Statistics)