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The Effects of Organic Surface Amendments on Soil Nutrients and Initial Tree EstablishmentThuesen, Kevin (Kevin Andrew) 05 1900 (has links)
This study examined the effects of replicating woodland soil surface horizonation on the nutrient status of underlying soils and the initial establishment and growth of trees. A total of 283 container grown trees were planted in a bufferzone around a future landfill site. Control amendments consisted of an 8 cm layer (0.5 m3) of wood chips applied in a circular area of 4.6 m2 around the trees' planting pit. For the treatment, a 2.5 cm layer of composted biosolids (0.15 m3 or 80 Mg/ha) was applied in a circular area of 4.6 m2 around the trees' planting pit followed by an 8 cm layer (0.5 m3) of wood chips. The results indicate that the replication of woodland soil surface attributes using composted biosolids can significantly improve the nutrient status of underlying soil. Some significant effects were seen under control conditions, too. However, the effects on tree establishment and growth parameters were, for the most part, not statistically significant.
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The Microbial Ecology Of Listeria Monocytogenes As Impacted By Three Environments: A Cheese Microbial Community; A Farm Environment; And A Soil Microbial CommunityLekkas, Panagiotis 01 January 2016 (has links)
This dissertation examined the microbial ecology of Listeria monocytogenes in three distinctly different environments: a cheese microbial community; a farm environment; and a soil microbial community.
The aim of the first study was to investigate the effects of L. monocytogenes on the composition of the surface microflora on washed rind soft cheese. Two trials with washed rind cheeses that were inoculated with 100cfu cm⁻² of a L. monocytogenes six strain cocktail were conducted. The first trial had to be terminated early (day 28) as contamination of Pseudomonas spp. from the initial brine did not produce the expected characteristics of the cheese during the aging period. For the second trial, cheese samples were aged in the lab for 60 days according to the cheesemakers specifications. Surface cheese rind samples were collected from both control and inoculated cheeses every 7 days. Cheese rind samples were analyzed through the standard BAM method for enumeration of L. monocytogenes and through amplification of the V4 region of 16S rRNA and ITS regions for identification of the surface rind bacterial and fungal communities, respectively. Our data showed that Pseudomonas spp. significantly changed the composition of the microorganisms found on the surface of the rind while L. monocytogenes had little effect. In addition, although the concentration of L. monocytogenes increased to levels of 10⁶ cfu cm⁻² based on the enumeration data, the genetic data was not able to identify it in the flora due to the fact that other genera were found at much higher concentrations, which is a limitation of molecular methods used for identification of pathogens in foods.
For the second study the presence and incidence of L. monocytogenes on farms that either produce raw milk cheese or supply the milk for raw milk cheese production was investigated. Five farms were visited and in total 266 samples were collected from barn, environmental, and milk sites. L. monocytogenes prevalence was found to be at 6% from all the farms tested with 10 isolates found in the barn samples, 5 from environmental sites and 1 from milking equipment. Samples were identified to the genus level through a modified BAM method and speciated though multiplex PCR. Included in the pathogenic isolates was a DUP-1042B L. monocytogenes strain that has been implicated in major outbreaks, which emphasizes the adaptability and persistence of highly pathogenic stains in food manufacturing environments. Results from this study continue to support the fact that contaminated silage can be an important reservoir of the pathogen in a dairy farm setting. From our data and field observations we identified that drinking water sources for the animals is also an important reservoir of L. monocytogenes in farm environments. More importantly this study has shown the importance of continuous monitoring of environmental sites for the presence of the pathogen, particularly in silage.
Lastly manure amended soils in the northeastern U.S. were tested for the presence and survival of rifampicin resistant Escherichia coli (rE. coli), generic E. coli (gE. coli) and Listeria spp.. Both gE.coli and rE.coli samples were processed using either direct enumeration, MPN or bag enrichment methods. Samples were taken from both tilled and surface dairy solid manure-amended plots. Listeria samples were processed using a modified BAM method. Listeria presence was constant throughout the study. In contrast, rE. coli and gE. coli levels declined with time. The main conclusions of this study were that soil type, location and physical characteristics have a significant role in the survival of bacterial populations of rE. coli, gE. coli and Listeria spp. in soil. Dairy solids application does not seem to have a long term effect on the natural microbial population of soils. Tilling of soils results in increased survival of the bacterial population due to the fact that it increases soil pore size and facilitates moisture entry, which in turn has been shown to increase bacterial survival rates. Data from this research will assist in the creation of preventative measures that lead to the elimination of pathogen reservoirs. It will be further used to verify that a 120 day interval following manure application should be sufficient to ensure food safety of edible crops subsequently planted on these soils.
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As relações entre os poderes Executivo e Legislativo e a caracterização da barganha no processo orçamentário brasileiro / The relations between the Executive and Legislative branches and the characterization of the bargain in the brazilian budget processGraton, Luís Henrique Teixeira 26 March 2019 (has links)
Quando se trata do presidencialismo existente no Brasil, nas funcionalidades das partes envolvidas no processo orçamentário do governo federal até então independentes entre si, como bem explana a Teoria da Separação dos Poderes, são observáveis diversas falhas, em decorrência da discricionariedade atribuída ao Executivo na realização de despesas não obrigatórias e do interesse do Legislativo na política clientelista em poder executar emendas que beneficiem suas principais bases eleitorais. A hipótese é de que, diante da necessidade de aprovação de projetos para aumento de governabilidade determinado volume de emendas é executado e verbas despendidas, o que caracteriza a barganha entre os poderes Executivo e Legislativo, fenômeno dessa pesquisa. Sustentado pela teoria econômica da agência e da Formação de Coalizões, o objetivo aqui foi verificar a ocorrência desse fenômeno de barganha nos anos de 2000 a 2017 e, na existência desse, caracterizar os parlamentares que mais se beneficiaram dessa relação. Por meio de dados do governo federal, para se chegar a esse objetivo foram usadas técnicas econométricas de análise em dois estágios de dados em painéis não balanceados, que caracterizaram inicialmente as emendas parlamentares e posteriormente seus autores correlacionados aos seus respectivos comportamentos em votações no Congresso Nacional, assim como os aportes na execução de suas emendas pelo poder Executivo. Os testes estatísticos aqui aplicados corroboraram para a validação da hipótese da existência da barganha entre Executivo e Legislativo, observado no âmbito desse trabalho pela maior liberação de recursos aos parlamentares que mais apoiaram propostas executivas, podendo caracterizar assim os mais beneficiados dessa relação / When it comes to the existing presidentialism in Brazil, in the functionalities of the parties involved in the budget process of the federal government hitherto independent of each other, as well as the Theory of the Separation of Powers explains, several failures, as a result of the discretion attributed to the Executive in the execution of non-compulsory expenses and the interest of the Legislature in the pork-barrel policy in being able to execute amendments that benefit its main electoral bases. The hypothesis is that, given the need for approval of projects to increase governability, a certain volume of amendments is executed and money spent, which characterizes the bargain between the Executive and Legislative branches, phenomenon of this research. Underpinned by the Economic Theory of Agency and Formation of Coalitions, the objective here was to verify the occurrence of this phenomenon of bargaining in the years 2000 to 2017 and, in its existence, to characterize the parliamentarians who have most benefited from this relationship. By means of federal government data, econometric analysis techniques were used in two stages of data in unbalanced panels, which initially characterized the parliamentary amendments and later their authors correlated to their respective behaviors in voting in the National Congress, as well as the contributions in the execution of its amendments by the Executive branch. The statistical tests applied here corroborated the validation of the hypothesis of the existence of the Executive and Legislative bargain, observed in the scope of this work by the greater liberation of resources to the parliamentarians who most supported executive proposals, thus being able to characterize the most benefited of this relationship
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Growth and heavy metal uptake by cynodon dactylon grown in sludge-amended soil substrates.January 1993 (has links)
by Ngar, Yuen-ngor. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1993. / Includes bibliographical references (leaves 186-196). / Chapter Chapter 1 --- Introduction Page / Chapter 1.1 --- Sludge as a waste problem --- p.1 / Chapter 1.2 --- The degraded geological environment of Hong Kong --- p.2 / Chapter 1.3 --- Use of weathered granitic material and sand as planting media --- p.3 / Chapter 1.4 --- Need of soil improvement material --- p.4 / Chapter 1.5 --- Potential for land application of sewage sludge --- p.5 / Chapter 1.6 --- Objectives of study --- p.6 / Chapter 1.7 --- Significance of study --- p.6 / Chapter Chapter 2 --- Literature Review / Chapter 2.1 --- Soil organic amendment for vegetation establishment --- p.9 / Chapter 2.2 --- Types and properties of sewage sludge --- p.10 / Chapter 2.3 --- Guidelines for land application of sludge --- p.12 / Chapter 2.3.1 --- Cation exchange capacity --- p.13 / Chapter 2.3.2 --- Zinc equivalent concept --- p.14 / Chapter 2.4 --- Effects of sludge on soil chemical and physical properties --- p.15 / Chapter 2.4.1 --- Chemical properties --- p.15 / Chapter 2.4.2 --- Physical properties --- p.18 / Chapter 2.5 --- Effects of sludge application on vegetation --- p.19 / Chapter 2.5.1 --- Germination --- p.19 / Chapter 2.5.2 --- Grass growth --- p.20 / Chapter 2.6.1 --- Choice of heavy metals for study --- p.21 / Chapter 2.6.2 --- Factors governing heavy metal availability --- p.25 / Chapter 2.6.3 --- Effects of lime on sludge-amended soil and the heavy metal availability --- p.26 / Chapter 2.6.4 --- Assessing available sludge-borne heavy metals --- p.27 / Chapter Chapter 3 --- Germination and seedling growth of bermudagrass in sludge-amended sand and CDG / Chapter 3 .1 --- Introduction --- p.30 / Chapter 3.2 --- Experimental design --- p.31 / Chapter 3.3 --- Experimental results --- p.34 / Chapter 3.3.1 --- Seed germination --- p.34 / Chapter 3.3.2 --- Seedlings and biomass growth --- p.35 / Chapter 3.3.3 --- DTPA-Extractable heavy metals --- p.39 / Chapter 3.3.4 --- Total heavy metals in plant tissue --- p.44 / Chapter 3.3.5 --- Chemical properties of the soil substrates --- p.49 / Chapter 3.4 --- Discussion --- p.54 / Chapter 3.4.1 --- Germination --- p.54 / Chapter 3.4.2 --- Nutrient effect --- p.56 / Chapter 3.4.3 --- Heavy metal availability from substrates --- p.59 / Chapter 3.4.4 --- Heavy metal uptake by the seedlings --- p.61 / Chapter 3.4.4.1 --- Metal uptake efficiency --- p.61 / Chapter 3.4.4.2 --- Amount of heavy metal uptake --- p.63 / Chapter 3.4.5 --- Textural characteristics --- p.66 / Chapter 3.5 --- Conclusions --- p.67 / Chapter Chapter 4 --- Growth and heavy metal uptake by bermudagrass grown in sludge-amended substrates / Chapter 4.1 --- Introduction --- p.70 / Chapter 4.2 --- Experimental design --- p.71 / Chapter 4.3 --- Results --- p.74 / Chapter 4.3.1 --- Biomass growth --- p.74 / Chapter 4.3.2 --- Heavy metal content of plant tissues --- p.82 / Chapter 4.3.2.1 --- Heavy metal content of the shoot --- p.83 / Chapter 4.3.2.2 --- Heavy metal content of the root --- p.89 / Chapter 4.3.3 --- Comparing the heavy metal levels in the shoot and root portions --- p.93 / Chapter 4.3.4 --- DTPA-extractable heavy metal content in soil substrates --- p.94 / Chapter 4.3.5 --- Chemical properties of the substrates --- p.100 / Chapter 4.4 --- Discussion --- p.103 / Chapter 4.4.1 --- Shoot biomass (First clipping) --- p.104 / Chapter 4.4.2 --- Shoot biomass (Second clipping) --- p.105 / Chapter 4.4.3 --- Shoot biomass ratio between the two clippings --- p.107 / Chapter 4.4.4 --- Total shoot biomass --- p.108 / Chapter 4.4.5 --- Root biomass and root: shoot ratios --- p.112 / Chapter 4.4.5.1 --- Nutrient effect --- p.113 / Chapter 4.4.5.2 --- Heavy metal phytotoxicity --- p.115 / Chapter 4.4.6 --- Total biomass production --- p.117 / Chapter 4.5 --- Conclusions --- p.118 / Chapter Chapter 5 --- Effect of lime on the growth and heavy metal uptake of bermudagrass in sludge-amended substrates / Chapter 5.1 --- Introduction --- p.121 / Chapter 5.2 --- Experimental design --- p.123 / Chapter 5.3 --- Results --- p.125 / Chapter 5.3.1 --- Biomass growth --- p.126 / Chapter 5.3.2 --- DTPA-extractable heavy metals --- p.133 / Chapter 5.3.3 --- Heavy metal uptake by the shoot portion --- p.138 / Chapter 5.3.4 --- Heavy metal uptake by the root portion --- p.147 / Chapter 5.3.5 --- Comparing metal uptake between shoot and root portions --- p.151 / Chapter 5.3.6 --- Chemical properties of substrates --- p.155 / Chapter 5.4 --- Discussion --- p.157 / Chapter 5.4.1 --- Effect of sludge and lime treatments on pH --- p.158 / Chapter 5.4.2 --- Patterns of DTPA-extractable metals and plant uptake --- p.159 / Chapter 5.4.2.1 --- Variation of heavy metal levels with liming rates --- p.160 / Chapter 5.4.2.2 --- Variation of heavy metal levels with sludge loading rates --- p.161 / Chapter 5.4.2.3 --- Bermudagrass as metal accumulator --- p.162 / Chapter 5.4.3 --- Metal uptake by the root and shoot --- p.162 / Chapter 5.4.3.1 --- Antagonistic interactions --- p.163 / Chapter 5.4.3.2 --- Parititioning of heavy metals in shoot and root --- p.163 / Chapter 5.4.4 --- Poor biomass growth --- p.166 / Chapter 5.4.4.1 --- Heavy metal toxicity --- p.166 / Chapter 5.4.4.2 --- Effect of poor soil conditions --- p.167 / Chapter 5.5 --- Conclusions --- p.177 / Chapter Chapter 6 --- Conclusions / Chapter 6.1 --- Summary of findings --- p.179 / Chapter 6.2 --- Implications of the study --- p.180 / Chapter 6.3 --- Limitations --- p.182 / Chapter 6.4 --- Suggestions for further studies --- p.184 / References --- p.186 / Appendix
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Effect of amendment materials on physical properties of decomposed granite and the growth of native species. / 土壤改良劑對風化花崗岩土壤物理特性及本地植物生長的影響 / Tu rang gai liang ji dui feng hua hua gang yan tu rang wu li te xing ji ben di zhi wu sheng zhang de ying xiangJanuary 2009 (has links)
Choi, Yuk Kam. / Thesis submitted in: December 2008. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 204-221). / Abstracts in English and Chinese. / Abstract --- p.i / Abstact (in Chinese) --- p.iv / Acknowlegement --- p.vi / Table of contents --- p.viii / List of tables --- p.xiii / List of figures --- p.xv / List of plates --- p.xvi / Chapter CHAPTER 1 --- INTRODUCTION --- p.1 / Chapter 1.1 --- Research background --- p.1 / Chapter 1.2 --- Conceptual framework --- p.3 / Chapter 1.3 --- Research objectives --- p.10 / Chapter 1.4 --- Significance of the study --- p.10 / Chapter 1.5 --- Organization of this thesis --- p.11 / Chapter CHAPTER 2 --- LITERATURE REVIEW --- p.13 / Chapter 2.1 --- Introduction --- p.13 / Chapter 2.2 --- Hong Kong's forestry and use of native species in ecological restoration --- p.14 / Chapter 2.3 --- Factors limiting the use of native species in ecological rehabilitation --- p.17 / Chapter 2.4 --- The climate and soils in Hong Kong --- p.19 / Chapter 2.5 --- Soil physical properties --- p.22 / Chapter 2.5.1 --- Soil water and water holding capacity --- p.23 / Chapter 2.5.2 --- Penetration resistance --- p.26 / Chapter 2.5.3 --- Soil structure --- p.27 / Chapter 2.6 --- Soil amendment materials --- p.29 / Chapter 2.6.1 --- Compost --- p.30 / Chapter 2.6.2 --- Coconut meal --- p.32 / Chapter 2.6.3 --- Water absorbing polymer --- p.35 / Chapter 2.7 --- Summary --- p.39 / Chapter CHAPTER 3 --- EFFECT OF AMENDMENT MATERIALS ON PHYSICAL PROPERTIES OF DECOMPOSED GRANITE AND THE GROWTH OF SCHIMA SUPERBA : GREENHOUSE EXPERIMENT I --- p.41 / Chapter 3.1 --- Introduction --- p.41 / Chapter 3.2 --- Materials and methods --- p.42 / Chapter 3.3 --- Experimental design --- p.43 / Chapter 3.3.1 --- "Amending DG with water absorbing polymer, coconut meal and compost" --- p.43 / Chapter 3.3.2 --- Watering treatment --- p.45 / Chapter 3.3.3 --- Post-planting treatment --- p.47 / Chapter 3.3.4 --- Monitoring of penetration resistance and soil moisture content --- p.48 / Chapter 3.4 --- Plant growth measurement --- p.49 / Chapter 3.4.1 --- Survival rate --- p.49 / Chapter 3.4.2 --- Height and basal diameter --- p.49 / Chapter 3.4.3 --- Chlorophyll fluorescence --- p.49 / Chapter 3.4.4 --- Aboveground biomass --- p.50 / Chapter 3.5 --- Laboratory analysis --- p.50 / Chapter 3.5.1 --- Texture --- p.50 / Chapter 3.5.2 --- Reaction pH and conductivity --- p.51 / Chapter 3.5.3 --- Organic carbon of soil and the amended substrates --- p.51 / Chapter 3.5.4 --- Total carbon of coconut meal and compost --- p.51 / Chapter 3.5.5 --- Total Kjeldahl Nitrogen --- p.52 / Chapter 3.5.6 --- Total phosphorus --- p.52 / Chapter 3.5.7 --- Exchangeable A1 and H and total exchangeable acidity --- p.53 / Chapter 3.5.8 --- "Total potassium, sodium,calcium and magnesium" --- p.53 / Chapter 3.5.9 --- Heavy metals --- p.53 / Chapter 3.5.10 --- Exchangeable cations --- p.53 / Chapter 3.5.11 --- Water absorbency of water absorbing polymer --- p.54 / Chapter 3.5.12 --- Water retention capacity --- p.54 / Chapter 3.5.13 --- Mean weight diameter --- p.54 / Chapter 3.6 --- Statistical analysis --- p.55 / Chapter 3.7 --- Results and discussion --- p.55 / Chapter 3.7.1 --- Properties of decomposed granite --- p.55 / Chapter 3.7.2 --- "Properties of water absorbing polymer, coconut meal and compost" --- p.58 / Chapter 3.8 --- Effects of amendment materials on DG --- p.60 / Chapter 3.8.1 --- Penetration resistance --- p.60 / Chapter 3.8.2 --- Soil moisture --- p.64 / Chapter 3.8.3 --- Water release characteristic curves and available water content --- p.69 / Chapter 3.8.4 --- Effect of amendment materials on soil organic carbon --- p.74 / Chapter 3.8.5 --- Relationship between SOC and water release characteristics --- p.77 / Chapter 3.8.6 --- Mean weight diameter --- p.78 / Chapter 3.9 --- Effects of amendment materials on the growth of Schima superba --- p.81 / Chapter 3.9.1 --- Survival rate --- p.81 / Chapter 3.9.2 --- Height and basal diameter increment --- p.84 / Chapter 3.9.3 --- Aboveground biomass --- p.88 / Chapter 3.9.4 --- Chlorophyll florescence --- p.89 / Chapter 3.10 --- Summary --- p.91 / Chapter CHAPTER 4 --- EFFECT OF AMENDMENT MATERIALS ON PHYSICAL PROPERTIES OF DECOMPOSED GRANITE AND THE GROWTH OF CASTANOPSIS FISSA: GREENHOUSE EXPERIMENT II --- p.94 / Chapter 4.1 --- Introduction --- p.94 / Chapter 4.2 --- Materials and methods --- p.95 / Chapter 4.2.1 --- Materials --- p.95 / Chapter 4.2.2 --- Experimental design --- p.96 / Chapter 4.2.3 --- Preparation of growth substrates --- p.96 / Chapter 4.2.5 --- Soil sampling --- p.98 / Chapter 4.2.6 --- Monitoring of soil moisture change and penetration resistance --- p.99 / Chapter 4.2.7 --- Plant growth measurement --- p.100 / Chapter 4.2.8 --- Laboratory analysis --- p.101 / Chapter 4.3 --- Results and discussion --- p.101 / Chapter 4.3.1. --- Properties of DG --- p.101 / Chapter 4.3.2 --- Water absorbency of ALCOSORB® --- p.103 / Chapter 4.3.3 --- Effect of amendment materials on physical properties of DG --- p.103 / Chapter 4.3.4 --- Effect of soil amendment on water release characteristic curves --- p.109 / Chapter 4.3.5 --- Soil evaporation test --- p.113 / Chapter 4.3.6 --- Soil organic carbon --- p.119 / Chapter 4.3.7 --- Mean weight diameter --- p.121 / Chapter 4.3.8 --- Effects of amendment materials on the growth of Castanopsis fissa --- p.123 / Chapter 4.3.8.1 --- Survival rate --- p.123 / Chapter 4.3.8.2 --- Height and basal diameter --- p.126 / Chapter 4.3.8.3 --- Aboveground biomass --- p.132 / Chapter 4.3.8.4 --- Chlorophyll fluorescence --- p.134 / Chapter 4.4 --- Summary --- p.136 / Chapter CHAPTER 5 --- CAN WATER ABSORBING POLYMER BENEFIT QUARRY REHABILITATION IN THE DRY SEASON? --- p.139 / Chapter 5.1 --- Introduction --- p.139 / Chapter 5.2 --- The study area --- p.142 / Chapter 5.2.1 --- The Anderson Road Quarry --- p.142 / Chapter 5.2.2 --- Rehabilitation of Anderson Road Quarry --- p.143 / Chapter 5.3 --- Experimental design --- p.145 / Chapter 5.3.1 --- Site preparation --- p.145 / Chapter 5.3.2 --- Selection of native species for planting --- p.147 / Chapter 5.3.3 --- The planting --- p.148 / Chapter 5.3.4 --- Data logging the growth environment --- p.150 / Chapter 5.3.5 --- Plant growth measurement --- p.150 / Chapter 5.3.6 --- Soil sampling and analysis --- p.151 / Chapter 5.4 --- Statistical analysis --- p.151 / Chapter 5.5 --- Results and discussion --- p.152 / Chapter 5.5.1 --- Properties of decomposed granite in ARQ --- p.152 / Chapter 5.5.2 --- Survival rate --- p.155 / Chapter 5.5.3 --- Height and basal diameter increments --- p.157 / Chapter 5.5.4 --- Major limiting factors for the establishment of seedlings --- p.160 / Chapter 5.5.4.1 --- Drought --- p.160 / Chapter 5.5.4.2 --- Soil erosion caused by rainstorm --- p.163 / Chapter 5.6 --- Summary --- p.165 / Chapter CHAPTER 6 --- EFFECT OF WATER ABSORBING POLYMER ON THE GROWTH OF NATIVE SPECIES IN A RESTORED QUARRY --- p.167 / Chapter 6.1 --- Introduction --- p.167 / Chapter 6.2 --- Study area --- p.168 / Chapter 6.3.2 --- Data logging the growth environment --- p.169 / Chapter 6.3.3 --- Plant growth measurement --- p.169 / Chapter 6.3.4 --- Spatial variation of irrigation water --- p.170 / Chapter 6.4 --- Statistical analysis --- p.170 / Chapter 6.5 --- Results and discussion --- p.170 / Chapter 6.5.1 --- Survival rate --- p.170 / Chapter 6.5.2 --- Height and basal diameter increments --- p.178 / Chapter 6.5.3 --- Growth environment in Anderson Road Quarry --- p.185 / Chapter 6.5.4 --- Weed competition --- p.189 / Chapter 6.6 --- Summary --- p.190 / Chapter CHAPTER 7 --- CONCLUSIONS --- p.191 / Chapter 7.1 --- Summary of major findings --- p.191 / Chapter 7.2 --- Implications of the study --- p.196 / Chapter 7.3 --- Limitations of the study --- p.199 / Chapter 7.4 --- Suggestions for further study --- p.200 / REFERENCES --- p.204 / APPENDICES --- p.222
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Salt Movement and Forage Crop Establishment in a Saline-Alkali Soil as Influenced by Ridges and Furrows, Sprinkler Irrigation, and Soil AmendmentsPurnell, D. C. 01 May 1953 (has links)
An estimated two to four million acres of irrigable saline and alkali soils of the United States return very little income to land owners (17,19). Increased needs for forage crops, and the relatively high salt and alkali tolerance of some improved forage species, once established, suggests a way of increasing revenue from some of these lands without costly reclamation.
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Effects of Biochar-Amended Soil on the Water Quality of Greenroof RunoffBeck, Deborah Aileen 01 January 2010 (has links)
As the numbers of installed greenroofs continue to grow internationally, designing greenroof growing media to reduce the amount of nutrients in the stormwater runoff is becoming essential. Biochar, a carbon-net-negative soil amendment, has been promoted for its ability to retain nutrients in soils and increase soil fertility. This study evaluated the effect on water quality of greenroof runoff after adding biochar to a typical extensive greenroof soil. Prototype greenroof trays with and without 7% biochar (by weight) were planted with sedum or ryegrass, with barren soil trays for controls. The greenroof trays were subjected to two sequential 2.9 in/hr rainfall events using a rainfall simulator. Runoff from the rainfall events was collected and evaluated for total nitrogen, total phosphorus, nitrate, phosphate, total organic carbon, and inorganic carbon. Greenroof trays containing biochar showed lower quantities of nutrients in the stormwater runoff compared to trays without biochar. Biochar-amended soil with and without plants showed a 3- to 25-fold decrease in release of nitrate and total nitrogen concentrations, as well as a decrease in phosphate and total phosphorus concentrations release into the rainfall runoff. Phosphorus results from trays planted with sedum indicate that sedum interacted with both soils to cause a decrease of phosphorus in the greenroof runoff. In correlation with a visual effect in turbidity, biochar-amended soil showed a reduction of total organic carbon in the runoff by a factor of 3 to 4 for all soil and plant trays. Inorganic carbon was similar for all tests showing that inorganic carbon neither reacted with, nor was retained by, biochar in the soil. The addition of biochar to greenroof soil is an effective way to retain nutrients in a greenroof soil, reduce future fertilizer demands, and improve the water quality of the stormwater runoff by reducing nitrogen, phosphorus, and total organic carbon concentrations in the runoff water.
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Organic soil amendements (sic) : impacts on snap bean common root rot and soil qualityCespedes Leon, Maria Cecilia 31 May 2002 (has links)
Common root rot is a major disease of commercially grown snap bean
(Phaseolus vulgaris L.) on the irrigated sandy soils of central Wisconsin. The
objective of this study was to determine the relationships between soil properties
and suppressiveness to common root rot of snap bean (causal agent Aphanomyces
euteiches) in soils. The soils had been annually amended for three years in a field
trial on a Plainfield sandy loam in Hancock, WI. Soils were amended each year
from 1998 to 2001 with three rates of fresh paper-mill residuals (0, 22 or 33 dry Mg
ha�����) or composted paper-mill residuals (0, 38 or 76 dry Mg ha�����). Soil was
removed from each treatment in April (one year after last amendment) and brought
to the laboratory. This was repeated with a field soil sample taken in September,
2001. The soils from the two samplings were incubated at room temperature and
periodically assayed (days 9, 44, 84, 106, 137, 225 and 270 for April sampling)
(days 13, 88 and 174 for September sampling) for suppressiveness of snap bean
root rot (0 to 4 where 0=healthy and 4=dead plant). The same days, incubated
soils were characterized for ��-glucosidase, arylsulfatase and fluorescein diacetate
activities; microbial biomass C (by chloroform fumigation); water stable
aggregation (WSA) and total C. In the first incubation, there were large differences
between field amendment treatments in terms of snap bean root rot incidence. The
disease was suppressed by both fresh and composted amendments, but compost
was most suppressive at high compost rates with disease incidence <40% which are
considered healthy plants that can reach full yield potential. In the second
incubation, disease severity difference among treatments were similar to the first
incubation. This would indicate the suppression was induced prior to initiation of
this experiment.
Disease severity of bean plants grown in unamended field soil was high but
in amended soils tended to decrease in intensity over time. Root rot severity was
negatively related to ��-glucosidase, and microbial biomass at the beginning and the
end of the first incubation period, respectively. FDA hydrolysis was not correlated
with disease severity and WSA moderately correlated with disease. The best
indicator of disease severity was arylsulfatase which was significantly and
negatively correlated with disease severity in 4 of 5 sampling periods. / Graduation date: 2003
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Soil degradation and rehabilitation in humid tropical forests (Sabah, Malaysia) /Ilstedt, Ulrik. January 2002 (has links)
Thesis (doctoral)--Swedish University of Agricultural Sciences, 2002. / Abstract inserted. Appendix reprints four papers and manuscripts co-authored with others. Includes bibliographical references. Also partially issued electronically via World Wide Web in PDF format; online version lacks appendix.
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Women of the Heartland tradition and evolution in the Missouri women's movement /Deken, John C., Rymph, Catherine E. January 2009 (has links)
Title from PDF of title page (University of Missouri--Columbia, viewed on Feb 17, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Thesis advisor: Dr. Catherine Rymph. Includes bibliographical references.
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