Research & reports

QI Airon · · China

A study of Xi'an, China, built indicators for urbanization and urban agriculture development and applied principal component analysis and correlation analysis to examine their interaction mechanism and quantitative coupling relationship. Urbanization was found to promote urban agriculture's commercialization and scale through market effects and information diffusion, but rapid urbanization's rising population and industrial land use also strained land and water resources and degraded soil and the urban ecological environment, constraining urban agricultural development.

Minjae Kong, Kwang-Lai Park, Jin-Kwan Son, Ji-Hoon Shin · Journal of the Korea Society of Environmental Restoration Technology · South Korea (Seoul)

This study investigated the characteristics of rooftop gardens (farms) in 40 areas in Seoul, Korea. Cabbage, lettuce, pepper, and mini-tomatoes were the most preferred vegetables and fruits. Problems observed in rooftop gardens during cultivation included drainage systems, soil management, the cost or quality of planting mats, and diseases and insects.

FU Li-hua · 自然资源学报 · China (Shanghai)

A study of Shanghai, China, building an evaluation index system reflecting the characteristics of sustainable urban agricultural development, using a combination of the analytic hierarchy process (AHP) and the information entropy method to determine index weights, and applying it to time-series data from 1993 onward to produce a quantitative, comprehensive appraisal. The results comprise three findings. First, the population subsystem progressively became a main obstructive factor for sustainable urban agricultural development, the economic subsystem gradually became a main contributing factor, and the social subsystem grew more important in raising development capability, while cultivated land resources became increasingly scarce and continued to decrease, constraining improvement, and the heavy burden of agricultural production's self-pollution had a negative effect on the overall upgrade of development capability. Second, the resource (R-D) composite index was not high and declined significantly, averaging 1.9090 over 1993-2006 and falling 6.00% per year from 2.5336 in 1993 to 0.5541 in 2006, indicating growing resource pressure; the environmental (E-D) composite index was smaller and changed little, remaining around 1.0000 in most years, with environmental pressure staying high but stable. Third, after earlier wave-like fluctuations, the overall composite evaluation index entered a sustained, steady climb, with a significant increasing trend in development capability.

Chandra Sen · Journal of Interdisciplinary Economics · India

This study estimated the impact of air pollution on crop yields in peri-urban areas of Varanasi, India. Phytotoxic gases are known to cause major yield reductions in important crops in developing countries, and in this study all major crops grown in peri-urban Varanasi — paddy, pigeon pea, maize, wheat, and potato — showed yield reductions attributable to air pollution. Air pollution was found to reduce both the yield and the nutritional quality of the produce, and the study calls for similar validation studies in other cities and for efforts to reduce air pollution in the city to improve crop yield and quality.

Mattia Celio, Christopher A. Scott, Mark Giordano · Geographical Journal · India (Hyderabad)

A study in Hyderabad, India, examined urban water capture and its impacts on pre-existing claims, particularly agriculture. Urban water appropriation often leads to conflict with existing water uses. The findings indicate that the magnitude and direction of impacts from urban water transfer on agriculture vary spatially and temporally, depending on location-specific rainfall patterns, existing water infrastructure and institutions, and farmers' adaptive capacities, including recourse to groundwater.

P. S. Datta, Shipra Tyagi · · India

Peri-urban agriculture in the Delhi-NCR area is highly dependent on groundwater availability amid rapid urbanization. This study integrates dynamic δ18O isotopic composition data on groundwater with static data such as elevation of recharge sites to delineate potential recharge zones and hydrodynamic aquifer zones. Significant δ18O-elevation relationships were found (r² = 0.808 to 0.982), with recharge-site elevation resolutions of about 20m in the northwest and 75m in the southwest, identifying potential recharge zones at elevations of 210-230m in the northwest and above 260m in the south. However, variation in groundwater isotopic composition over time indicates that the corresponding aquifers are relatively small and of low productivity, and points to the likely presence of many low-permeability zones in the northwestern recharge areas — a constraint on the groundwater resources that sustain peri-urban agriculture there.

Kenny Lynch · · Indonesia (Jakarta)

This piece reviews the literature on urban agriculture (UA), noting that Bryceson (1993) provides documentary evidence from as early as 1939 of UA's importance during and after the Second World War, and that the UN University's Food Energy Nexus research programme in the mid-1980s prompted researchers to examine agricultural cultivation within city boundaries more seriously. Since then, a significant body of literature has developed around a central debate over whether urban agriculture is beneficial, summarized by Lynch (2002). This summary is described as having two problems: it assumes urban agriculture is a homogenous activity with universally similar impacts, and it is largely viewed from the perspective of a city's population, so urban agriculture tends to be seen as beneficial for food, employment and the environment with little consideration of its impacts on the rural-urban food supply. This led Lynch, Binns and Olofin (2001) to argue that urban agriculture should instead be considered part of the broader urban food supply system.

James M. Wolf, M S van Wijk, X Cheng, Yuanhao Hu, C.A. van Diepen, A.W. Jongbloed, H van Keulen, C H Lu, R.P. Roetter · Environment and Urbanization · China (Beijing)

This paper reviews agricultural production trends in Beijing Municipality and their impact on water quality. Rapid urbanization and agricultural intensification have led to concerns regarding water resource quantity and quality. The agricultural sector, while supplying food, is a major water user and has contributed to significant water supply-demand gaps and high levels of water pollution, particularly from intensive crop, vegetable, and livestock production.