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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Is vertical farming a more sustainable alternative to conventional farming in Hong Kong?

Cheng, Kwok-hang, 鄭國鏗 January 2014 (has links)
Hong Kong’s agricultural sector has been declining since the 1980s with the reduction in area of arable lands and number of farmers. The trend of over-reliance on imported produce is likely to continue with population growth in the upcoming decades. The climbing imported to locally grown food ratio might aggravate climate change. Vertical farming, which is promoted in recent years as a more sustainable mode of farming than conventional cultivation, is investigated mainly in terms of life cycle Greenhouse gases (GHG) emissions of its produce. Assessment was carried out following the guidelines in two relevant sets of Publicly Available Specification (PAS). Lettuce variety “Heading European”, which is among the most popular leafy vegetables in Hong Kong, is chosen because of its significant share imported from Guangdong Province. Three sets of surveys have been conducted to find out if locally grown produce generates less GHG than imported one. The sustainability of vertical farming is also evaluated. It performs in a cradle-to-gate basis in which life cycle of the lettuce is assessed from the stage of farmland preparation to delivery of them to Vegetable Marketing Organization (VMO). The results of life cycle GHG evaluation show that produce of local farm generates fewer amounts of GHGs than the imported one. For lettuces imported from the conventional farm in Songyuancun, Guangdong Province, it generates approximately 1.57E+00kg of carbon dioxide equivalent (CO2-e). It is about 132% higher than the one grown in local conventional farm at Tai Kong Po Tsuen, which is around 6.77E-01kg of CO2-e It seems the idea of replacing local conventional farming with vertical farming is not sustainable at this stage. Evaluation reveals the latter generates more amount of GHG which is 8.72E+00kg CO2-e/cup of Oak Leaf Lettuce. It is about 13 times higher than the locally grown in the conventional farm. The energy-hungry lighting system and the lack of renewable energy are among the major reasons for high GHG emission in vertical farming. Although the GHG emissions are higher than conventional farming in the designated lifecycle, vertical farming does contribute to sustainable development in terms of food stability and job opportunity. Uncertainties of this study could well be improved by developing a specific set of GHG emission factors for components in preparation stage and on-farm stage. More information could be collected for use and end-of-life stages, which is omitted in the study. Further comparison of wider variety of vegetables cultivated in different forms of farming should also be carried out. Carbon labelling scheme for agricultural products would brush up environmental awareness of both producers and consumers. With the trend of green consumption, it would provide an incentive for producers to adopt this scheme. It is especially important for local vertical farms to impose this scheme to increase its market competiveness. Moreover, government should play a significant role in promoting a more sustainable form of agriculture. Supportive policy like increasing investment in R&D for energy efficient technologies or even erecting a modern building for vertical farms would help achieve this goal. The lowered life cycle GHG emission would enhance sustainability of vertical farming. / published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
12

Agricultural land use planning and management in Guangdong

黃梅, Wong Mui, Christina. January 1996 (has links)
published_or_final_version / Urban Planning / Master / Master of Science in Urban Planning
13

Land and people in Tung Chung Valley: an example of rural land use in Hong Kong

Ng, Cheuk-yiu, 吳卓堯 January 1965 (has links)
published_or_final_version / Geography and Geology / Doctoral / Doctor of Philosophy
14

Land use in the eastern extremities of the New Territories, Hong Kong

Chiu, Tze-nang., 趙子能. January 1961 (has links)
published_or_final_version / Geography and Geology / Master / Master of Arts
15

A study of the Daping Yao peasant economy.

January 1989 (has links)
So Sung-wan. / Thesis (M.Phil.)--Chinese Universiry of Hong Kong, 1989. / Bibliography: leaves 244-250.
16

Evolution of urban agriculture in Hong Kong: stepping towards multifunctionality. / 香港都市農業向多功能性的演進 / CUHK electronic theses & dissertations collection / Xianggang du shi nong ye xiang duo gong neng xing de yan jin

January 2013 (has links)
Lau, Hoi Lung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 156-172). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts also in Chinese; appendix I in Chinese.
17

Sustainable agriculture: a case study of contour hedgerows in Zigui County, Hubei Province, China.

January 2004 (has links)
Tang Chi Wai. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (leaves 104-121) and index. / Abstracts in English and Chinese. / Abstract --- p.i / 摘要 --- p.iii / Acknowledgements --- p.v / Table of Contents --- p.vii / List of Tables --- p.x / List of Figures --- p.xi / List of Plates --- p.xii / Chapter Chapter One --- Introduction / Chapter 1.1 --- Background --- p.1 / Chapter 1.2 --- Conceptual Framework --- p.3 / Chapter 1.3 --- Objectives and Significance --- p.5 / Chapter 1.4 --- Structure of the Thesis --- p.7 / Chapter Chapter Two --- Literature Review / Chapter 2.1 --- Impacts of Soil Erosion on Agriculture --- p.8 / Chapter 2.2 --- Farmland Shortage Problems in the Reservoir Region --- p.10 / Chapter 2.3 --- Terracing Systems in China --- p.11 / Chapter 2.4 --- Contour Hedgerows --- p.13 / Chapter 2.5 --- Sustainable Agriculture and its Development in China --- p.18 / Chapter Chapter Three --- Study Area / Chapter 3.1 --- The Three Gorges Reservoir Region --- p.22 / Chapter 3.2 --- Geographical Settings of Zigui County --- p.23 / Chapter 3.2.1 --- Geographical and Administrative Location --- p.23 / Chapter 3.2.2 --- Geology and Geomorphology --- p.24 / Chapter 3.2.3 --- Soils --- p.25 / Chapter 3.2.4 --- Climate --- p.25 / Chapter 3.2.5 --- Hydrology --- p.26 / Chapter 3.3 --- Socioeconomic Conditions of Zigui County --- p.26 / Chapter 3.3.1 --- Demography --- p.26 / Chapter 3.3.2 --- Educational Attainments --- p.27 / Chapter 3.3.3 --- Economic and Social Development --- p.27 / Chapter 3.4 --- Environmental Problems in Zigui and the Reservoir Region --- p.28 / Chapter Chapter Four --- Cost-benefit Analysis of Contour Hedgerows / Chapter 4.1 --- Introduction --- p.30 / Chapter 4.2 --- Methodology --- p.32 / Chapter 4.2.1 --- Trial Plot Design --- p.32 / Chapter 4.2.2 --- Cost-benefit Analysis --- p.35 / Chapter 4.2.3 --- Identification and Valuation of Costs --- p.35 / Chapter 4.2.4 --- Identification and Valuation of Benefits --- p.37 / Chapter 4.2.5 --- Discount Rate --- p.37 / Chapter 4.2.6 --- Time Horizon --- p.37 / Chapter 4.2.7 --- Cost-benefit Criterion --- p.38 / Chapter 4.3 --- Results and Discussion --- p.38 / Chapter 4.3.1 --- Investment Costs and Operating Costs --- p.38 / Chapter 4.3.2 --- Replacement Costs --- p.39 / Chapter 4.3.3 --- Benefits --- p.42 / Chapter 4.3.4 --- Net Present Values (NPVs) --- p.44 / Chapter 4.3.5 --- Sensitivity Analysis --- p.47 / Chapter 4.4 --- Conclusion --- p.48 / Chapter Chapter Five --- A Questionnaire Survey of the Comparative Performance of Various Farming Systems / Chapter 5.1 --- Introduction --- p.50 / Chapter 5.2 --- Methodology --- p.52 / Chapter 5.2.1. --- Sampling Method --- p.52 / Chapter 5.2.2. --- Questionnaire --- p.52 / Chapter 5.2.3. --- Analytical Technique --- p.53 / Chapter 5.3 --- Results and Discussion --- p.54 / Chapter 5.3.1. --- Background of Households and Farming Systems --- p.54 / Chapter 5.3.2. --- Net Returns --- p.57 / Chapter 5.3.3. --- Inputs of Inorganic Fertilizers and Organic Manure --- p.61 / Chapter 5.3.4. --- Labour Inputs --- p.64 / Chapter 5.3.5. --- Characteristics of Hedgerow Management --- p.65 / Chapter 5.4 --- Conclusion --- p.66 / Chapter Chapter Six --- An Interview Study of the Perception of Contour Hedgerows / Chapter 6.1 --- Introduction --- p.68 / Chapter 6.2 --- Methodology --- p.70 / Chapter 6.3 --- Results and Discussion --- p.72 / Chapter 6.3.1 --- Familiarity with Hedgerows --- p.72 / Chapter 6.3.2 --- Hedgerow Acceptance in Usage --- p.74 / Chapter 6.3.3 --- Factors of Hedgerow Implementation --- p.79 / Chapter 6.3.4 --- Variation of Agricultural Inputs and Outputs --- p.83 / Chapter 6.3.5 --- Values of Indigenous Knowledge --- p.86 / Chapter 6.3.6 --- Implications for Hedgerow Extension --- p.88 / Chapter 6.4 --- Conclusion --- p.90 / Chapter Chapter Seven --- Conclusion / Chapter 7.1 --- Summary of Findings --- p.92 / Chapter 7.2 --- Synthesis of the Study --- p.95 / Chapter 7.3 --- Limitations of the Study --- p.100 / Chapter 7.4 --- Suggestions for Further Studies --- p.101 / Bibliography --- p.104 / Appendix I: Structured Questionnaire --- p.122 / Appendix II: Interview Guide for Hedgerow Users --- p.131 / Appendix III: Interview Guide for Non-hedgerow Users --- p.134 / Appendix IV: Interview Guide for Government Officials --- p.137 / Appendix V: Index --- p.140 / "Appendix VI: Publication-Cost-benefit Analysis of Contour Hedgerow in the Three Gorges Region (Published in ´ب´بResources Science´ح,Vol26 Supplement,pp. 132-136)" --- p.145
18

Politics in command: the origin of late reform in northeast China. / 指令政治: 改革時代中國東北地區落後原因的探尋 / Zhi ling zheng zhi: Gai ge shi dai Zhongguo dong bei di qu luo hou yuan yin de tan xun

January 2009 (has links)
Wei, Yifan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2009. / Includes bibliographical references (leaves 165-172). / Abstract also in Chinese. / Abstract (English) --- p.2 / Abstract (Chinese) --- p.3 / Acknowledgement --- p.4 / Chapter Chapter 1 --- Introduction --- p.7 / Research Question / Research Objective / Methodology / Chapter Chapter 2 --- Literature Review --- p.18 / The State and Economy / Debate on China´ةs Reform / Underdevelopment and Northeast China / Chapter Chapter 3 --- Military --- p.50 / Geo-political Importance / Defense Conversion / New Reform / Conclusion / Chapter Chapter 4 --- Agriculture --- p.75 / Background of Agricultural Production / Strategic Position in Food Security / The State and Agricultural Predicament / Conclusion / Chapter Chapter 5 --- Secondary Industry --- p.107 / The State's Industrial Investment / Fiscal and Material Contribution / State-owned Enterprises / Struggling in the Market / Conclusion / Chapter Chapter 6 --- Conclusion --- p.150 / Research Findings / Implications on China´ةs Reform / Appendix --- p.162 / Bibliography --- p.163
19

Assessment of the effects of agricultural practices on amphibian populations in Long Valley wetlands, Hong Kong

Ma, Chui-ying., 馬翠盈. January 2012 (has links)
Agricultural practices have altered natural wetland habitats for thousands of years in lowland areas of Southeast Asia, and currently these highly modified wetlands constitute some of the most important remaining habitats for amphibians. However, decreasing area of arable land and increased use of chemicals may affect the persistence of lowland amphibian populations that are now dependent on these habitats. I investigated how amphibians responded to different kinds of farming treatments in a large agricultural wetland in Hong Kong. In the first part of the study, I assessed the occurrence of breeding amphibians in 53 farming plots in 2010 and 2011. Anuran call surveys were conducted at night at the plots once a week from March to August for two years. Environmental variables were measured and used to develop models to examine species presence, occupancy, and detection probabilities. Wet agricultural plots supported 10 species of amphibians and all had detection probabilities of < 1 that varied seasonally and yearly. Organically managed plots and shallow water plots yielded high species richness and particularly attracted the ornate pygmy frog (Microhyla fissipes) and the paddy frog (Fejervarya limnocharis). Air temperature and humidity were the relatively consistent predictors that influenced calling activity of the four most commonly detected species (M. fissipes; F. limnocharis; brown tree frog Polypedates megacephalus; and G?nther’s frog Hylarana guentheri). For the second part of the study, I assessed the impacts of fertilizers on amphibians. Using mesocosm experiments in the field, I compared the effects of a chemical fertilizer (granular urea) and an organic fertilizer (peanut cake) on the survival and growth of hatchlings of Polypedates megacephalus, the marbled pygmy frog (Microhyla pulchra), Asian common toad (Duttaphrynus melanostictus) and Chinese bullfrog (Hoplobatrachus rugulosus). Fertilizers were applied at low, manufacturer-recommended, and high levels, and survival and snout-vent-length were measured after 21 days. No individuals survived in the chemical fertilizer treatment at the recommended application level. Conversely, survival was high for P. megacephalus (96%), M. pulchra (54%) and D. melanostictus (90%), but relatively low for H. rugulosus (18%), at the recommended level of the organic fertilizer. P. megacephalus and M. pulchra tadpoles showed increased growth in elevated concentrations of organic fertilizer. Polypedates megacephalus tadpoles were 1.6 times longer in the low concentration and almost double in length in the high concentration treatments. Similarly, increased growth in M. pulchra in all organic treatments resulted in abbreviated time to metamorphosis. Chemical fertilizers are clearly detrimental to early life stages of these amphibians, but organic fertilizers may confer benefits including a shorter time to, and larger size at, metamorphosis. These results suggest that where amphibian conservation is a priority, shifts in the management of wet agricultural crops and limiting the use of chemical fertilizers may increase the suitability of breeding habitats and survival at early life stages. / published_or_final_version / Biological Sciences / Master / Master of Philosophy
20

A study of three major agricultural land uses in north Yuen Long

Chan, Hung-kwan., 陳鴻錕. January 1970 (has links)
published_or_final_version / Geography and Geology / Master / Master of Arts

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