Cheng Chung-yin. / Thesis submitted in: December 2004. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (leaves 185-195). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgements --- p.vi / Table of contents --- p.viii / List of tables --- p.xi / List of figures --- p.xii / List of plates --- p.xiv / Plant species used in the experiments --- p.xv / Chapter 1 Introduction / Chapter 1.1 --- Soil wastes as an environmental challenge --- p.1 / Chapter 1.2 --- Landfilling --- p.1 / Chapter 1.2.1 --- Waste degradation --- p.4 / Chapter 1.2.2 --- Control of degradation by-products --- p.6 / Chapter 1.3 --- Landfill leach ate --- p.8 / Chapter 1.3.1 --- Generation and control of landfill leachate --- p.8 / Chapter 1.3.2 --- Leachate characterization --- p.10 / Chapter 1.3.3 --- Leachate from local landfills --- p.15 / Chapter 1.3.4 --- Leachate treatment --- p.15 / Chapter 1.4 --- Leachate irrigation --- p.16 / Chapter 1.4.1 --- Common practices of wastewater irrigation --- p.17 / Chapter 1.4.1.1 --- Spray irrigation / Chapter 1.4.1.2 --- Rapid infiltration / Chapter 1.4.1.3 --- Overland flow / Chapter 1.4.2 --- Effects of leachate irrigation --- p.19 / Chapter 1.4.2.1 --- Effect of leachate irrigation on soil percolate / Chapter 1.4.2.2 --- Effect of leachate irrigation on soil / Chapter 1.4.2.3 --- Effect of leachate irrigation on plants / Chapter 1.5 --- Landfilling in Hong Kong --- p.24 / Chapter 1.5.1 --- Climate --- p.24 / Chapter 1.5.2 --- Geography and economy --- p.25 / Chapter 1.5.3 --- Waste composition --- p.25 / Chapter 1.5.4 --- Leachate sampling sites --- p.27 / Chapter 1.6 --- Objectives of this study --- p.30 / Chapter 1.6.1 --- Knowledge gaps --- p.30 / Chapter 1.6.2 --- Project outline --- p.33 / Chapter Chapter 2 --- Phytotoxicity evaluation of landfill leachate using seed germination tests / Chapter 2.1 --- Introduction --- p.34 / Chapter 2.1.1 --- Tests involving the use of germinating seeds --- p.34 / Chapter 2.1.2 --- Importance of germination to plants --- p.34 / Chapter 2.1.3 --- Advantages of germination tests --- p.35 / Chapter 2.1.4 --- Limitations of using germination as an endpoint --- p.35 / Chapter 2.1.5 --- Methods of germination test --- p.36 / Chapter 2.1.5.1 --- Test design / Chapter 2.1.5.2 --- Plant species / Chapter 2.1.5.3 --- Measurement endpoints / Chapter 2.1.5.4 --- Statistical analysis and test endpoints / Chapter 2.2 --- Objectives of study --- p.41 / Chapter 2.3 --- Materials and methods --- p.42 / Chapter 2.3.1 --- Sample collection --- p.42 / Chapter 2.3.2 --- Chemical analysis --- p.42 / Chapter 2.3.3 --- Statistical analysis --- p.43 / Chapter 2.3.4 --- Phytotoxicity assay --- p.43 / Chapter 2.4 --- Results and discussion --- p.44 / Chapter 2.4.1 --- Leachate characterization --- p.44 / Chapter 2.4.1.1 --- Comparison among landfill sites / Chapter 2.4.2 --- Phytotoxicity assay --- p.51 / Chapter 2.4.2.1 --- Dose response relationships / Chapter 2.4.2.2 --- Implication of hormetic-like response on the selection of statistical model / Chapter 2.4.2.3 --- Phytotoxicity of leachate samples / Chapter 2.4.2.4 --- Comparison between species / Chapter 2.5 --- Conclusions --- p.65 / Chapter Chapter 3 --- Leachate irrigation: Effects on plant performance and soil properties / Chapter 3.1 --- Introduction --- p.67 / Chapter 3.2 --- Materials and methods --- p.70 / Chapter 3.2.1 --- Leachate sampling and analysis --- p.70 / Chapter 3.2.2 --- Leachate irrigation experiment --- p.71 / Chapter 3.2.3 --- Soil and plant analysis --- p.73 / Chapter 3.2.3.1 --- Soil sampling and preparation / Chapter 3.2.3.2 --- Soil texture / Chapter 3.2.3.3 --- pH and electrical conductivity / Chapter 3.2.3.4 --- Organic carbon / Chapter 3.2.3.5 --- Nitrogen / Chapter 3.2.3.6 --- Phosphorus / Chapter 3.2.3.7 --- Chloride / Chapter 3.2.3.8 --- Metals / Chapter 3.2.3.9 --- Foliage analysis / Chapter 3.3 --- Results and discussion --- p.75 / Chapter 3.3.1 --- Leachate --- p.75 / Chapter 3.3.1.1 --- Chemical properties / Chapter 3.3.1.2 --- Phytotoxicity / Chapter 3.3.2 --- Plant responses --- p.79 / Chapter 3.3.2.1 --- Growth / Chapter 3.3.2.2 --- Plant survival and health / Chapter 3.3.2.3 --- Tissue contents / Chapter 3.3.2.4 --- Incorporating the results of germination tests in leachate irrigation practice / Chapter 3.3.3 --- Soil --- p.101 / Chapter 3.3.3.1 --- Initial properties / Chapter 3.3.3.2 --- Soil reaction (pH) / Chapter 3.3.3.3 --- Nitrogen / Chapter 3.3.3.4 --- Phosphorus / Chapter 3.3.3.5 --- Conductivity / Chapter 3.3.3.6 --- Chloride / Chapter 3.3.3.7 --- Metals / Chapter 3.4 --- Conclusions --- p.119 / Chapter Chapter 4 --- Fate and distribution of N after soil application of landfill leachate / Chapter 4.1 --- Introduction --- p.121 / Chapter 4.1.1 --- The needs of external N supply in ecological restoration --- p.121 / Chapter 4.1.2 --- Objectives of study --- p.122 / Chapter 4.2 --- Materials and methods --- p.123 / Chapter 4.2.1 --- Leachate --- p.124 / Chapter 4.2.2 --- Soil column --- p.124 / Chapter 4.2.3 --- Plant selection and establishment --- p.127 / Chapter 4.2.3 --- Leachate application --- p.129 / Chapter 4.2.4 --- Post irrigation harvesting and analysis --- p.130 / Chapter 4.3 --- Results and discussion --- p.130 / Chapter 4.3.1 --- Leachate --- p.130 / Chapter 4.3.2 --- Plants --- p.132 / Chapter 4.3.2.1 --- Growth / Chapter 4.3.2.2 --- Tissue N contents / Chapter 4.3.3 --- Soil and soil percolate --- p.139 / Chapter 4.3.3.1 --- Percolate volume and soil moisture / Chapter 4.3.3.2 --- pH / Chapter 4.3.3.3 --- Electrical conductivity / Chapter 4.3.3.4 --- Nitrate / Chapter 4.3.3.5 --- Ammonium / Chapter 4.3.4 --- N balance of the soil-plant system --- p.160 / Chapter 4.3.4.1 --- Change in the N capital after leachate irrigation / Chapter 4.3.4.2 --- Leaching loss / Chapter 4.3.4.3 --- Unaccountable N loss / Chapter 4.4 --- Conclusions --- p.174 / Chapter Chapter 5 --- General conclusion / Chapter 5.1 --- Summary of findings --- p.176 / Chapter 5.2 --- Ecological consequence of increased and excess N deposition --- p.179 / Chapter 5.3 --- Research prospects --- p.182 / References --- p.185

published_or_final_version / Architecture / Master / Master of Landscape Architecture