LSGI 4321 Essay TopicCritics have argued that the roof of the current high housing price is the result of a mismatch of supplyand demand. Discuss how GIT can help facilitate a steady housing land supply to meet the demand. Tang Wing Yee Peony 09113226DIntroductionThe housing price in Hong Kong nowadays iscontinuously increasing. Although the government hasintroduced some new housing policy and increased therestriction on property transaction and the economicenvironment is still full of uncertain factors, theincreasing in property price is still having an adorableraise. Therefore, both the middle and lower incomeclasses can hardly afford to buy a place for living and itleads to social disharmony.Some said that if the government can ensure a steadyland supply, the current housing price may be reduced.In this essay, I will discuss how Geo-InformationTechnology (GIT) can help facilitate a steady housingland supply to meet the demand.Defining GITGIT is a mean for spatial analysis. It consists of both specialized information and communicationtechnology. Data includes resources, landscape features and socio-economic characteristics of an areawill be collected, managed and analyzed. It can then visualize the spatial data for communication,dissemination and knowledge sharing. Its major tools are Geo-Information System (GIS), Geo-positioningSystem (GPS), remote sensing and web-based tools.DefiningLand Supply, Land Capacity and DemandNaturally, the contentiousness of a highly politicized process that helps shaping the decisions of thedevelopment of urban increase according to the relative scarcity of land deemed “developable.” Thisneed to establish “definitions of available land supply agreed on by both private interest and thegovernment” continues to be a major issue with land monitoring.Typically, buildable lands are classified as vacant, partially utilized or underutilized. Vacant land is landwithout any significant uses. Partially utilized land is improved parcel that are sufficient vacant and allowadditional new construction without changing the existing structure. Underutilized land is property thatalready developed over most area, but considered likely to undergo demolition and replacement or
significant alteration of structure to yield more intense, more highly valued, or altogether different uses,usually means lands having redeveloping potential.Although adequate land supply is always assessed relatively to demand, it technically does not have tobe considered in determining the land supply and estimating the land capacity.However, if possible, weshould also consider the consumer preferences for housing type, sectoral employment growth, andchanges in construction and land development practices as well as dwelling unit versus employmentgrowth.As for Hong Kong, the land supply mainly sourced from government vacant land and renewal project,while the purchasers of the housing are usually investors and residents.Trend of using GIT in monitoring land supplyRecently, there is increasingly more concern on the impacts of future urban development throughgrowth-conscious planning and the development of GIT become more rapid, which helps doing thefunctions of planning and management. Since GIT is capable in perform several of functions that helpdoing sophisticated analyzes, modeling and visualizing, use of GIT in monitoring land supply becomesmore common and popular.How GIT facilitate the land supplyData CaptureBefore the processing, we need to develop a comprehensive land supply database, conduct an inventoryof the buildable land supply, estimate development capacity and apply land supply and capacityinformation to plan-making and plan implementation processes.Since the data collected are useful to other general planning activities and other government functions,also the monitoring and analysis approach may change over time, so it is important to separate thedatabase from the buildable land supply inventory and analysis. The database should be as completedand comprehensive as possible, if not the outcome may not be reliable and convincing.Generally, the database should include the following data types such as existing and planned land uses,zoning, other regulations that impose limits on density and use (usually imposed by the planningdepartments of the government to ensure a sustainable city development), land ownership information,environmental conditions, existing planning and infrastructure, etc.Remote sensing, one of the essential GIT tools, is definitely capable in collecting most of the aboveinformation. Remote sensing is the art and science of obtaining information about object, area, orphenomenon through the analysis of data acquired by a device that is not in contact with the object,area, or phenomenon under investigation.Using remote sensing, we can do land use classification, land use monitoring and environmentalobservation.
By image interpretation, we can do land use classification according to their shape, size, pattern, tone orhue, texture, shadow, site and association. For instance, texture helps distinguish urban and rural landuse. Shape helps recognize recreational land use such sport ground and swimming. Site, which is thegeographic location of the features, can help recognize commercial land use such as Central. Patternhelps us to distinguish residential and industrial land use. We can also recognize transportation land usesuch as roads and bus stations using pattern and association. More, it definitely helps us to identify thevacant land and partial utilized land.By image interpretation, we can able to monitorthe current use of land. This is really important,since if the land is used not correctly, theplanning that done previously will bemeaningless and the ordinary land supplystrategy would be ruined. For instance, illegalfarming activities on government land likemountain or national park can easily berecognized using aerial photo using pattern.Another example is that previously, that wasnews reported on July that some riches built thegate of their houses on government land and itshows clearly on aerial photo and posted onnewspaper and TV program. (For moreinformation, please visit the following website:http://www.hkatvnews.com/v5/news.php?id=151601&d=2011-07-18&cn=0)Another application is that using different bands, we can able to observe the natural environment inmany different aspects. For instance, using visible blue band, we can illuminate materials in shadows,observe the water penetration of bathymetry, soil and vegetation differentiation and deciduous andconiferous differentiation. Using visible green band, we can observe water penetration for bathymetry,clear and turbid water contrast, discrimination of oil on water and the green reflectance peak of healthyvegetation. Using visible red band, we can observe the vegetation differentiation and chlorophyllabsorption.Data Processing and outputBy inputting the information captured to GIS, the system will do visualization according to the spatialdata. User can choose to build 2D or 3D model depends on their need.After developing acomprehensive land supplydatabase, we can then conductan inventory of the developableland supply by delineating the
geographically specific and unit of land. As some lands may be excluded from the buildable land supplyeven they are vacant, partial utilized and underutilized land. These constraints include environmental orphysical factors, land ownership and lands that use for specific purpose.Recently that is a buildable landthat its development is for prohibited since this land is being classified as a historical heritage. Byinputting all these requirements of buildable land and set up the formula, GIS would perform the dataanalysis and it will able to identify the buildable land and select them in the model. Since the model isvisualized, it is possible for user to locate the buildable land easily and provide you the estimateddevelopment capacity.GIS is also useful in doing modelsimulation. As to lower the housingprice, the government has beenintroducing new housing policies andadjusting the housing strategy. Bychanging the value such as changingin land ownership after ending ofshort tern tenant treaty, increasingthe accessibility and infrastructure ofa place, and then inputted them inGIS, the system can help visualizethe new look of the studied area, dothe analysis about the influences ondifferent aspects such as sky view,ventilation, shadow, etc. as well asthe increase in land supply in a fastway. Using this would be convenience for the government to introduce effective strategy or guidelinesthat increase the land supply but at the same time minimize the harm that caused to the surroundingareas.Potentially, the land demand of Hong Kong will keep increasing, especially for residential andcommercial uses. Since land resources are limited, therefore different land usages are competing witheach other. Therefore, it is essential for the system to consider both factors. Since GIS can performassessment of potential amounts, pattern, and locations of future development within sub regionalareas of interest, it can definitely to forecast the future land demandand thus enable us tofacilitate asteady land supply in long term. Data Sharing Web-based tools are very useful GIT tools for data sharing. They includes Google map, GeoInfo Map, etc. Using this information can be shared internal or to the general public. They would be spatial information like addresses and site annotation as well as analyzed result such as transportation
path from one location to another and area of a building. Through this it is possible for everyone in thesociety in monitoring the land uses and comment on it. And the government may then able to receivegood and professional suggestion or recommendation from non-government institution such as theHong Kong Building Environmental Assessment Method Society.Another point is that some web-based tools can be running under an open-source system, whichenables all people that able to access to the internet to alter and update the existing information. This isgood for obtaining the latest information using less cost and time, thus, produce a system that reflectthe current states for land supply monitoring. However, if the information is invalid, it would be time-consuming to detect it and it may affect the accuracy of the system.Limitations and ChallengesOne limitation of using GIT to facilitate a steady land supply is deal to the capability and the accuracy ofthe data. Since some information required may be confidential, private or lost, it is hard, costly andtime-consuming to establish a completed and comprehensive database and so the updating. Also, theaccuracy of the data collected may not be that precise, this is because the resolution of the digital imageis bad that affect the image interpretation, the site knowledge of the image obtainer is low and the datacaptured may not be updated. All these will then affect the usefulness of the model in monitoring theland supply.Another limitation is that resources should be continuously inputted for the system maintenance.Although the version of GIS system is being more and more advanced and providing users’ without morefunctions, it is very costly and the users’ may need time to adopt the new system.Also, since human behaviors are difficult to predict as well as the market conditions. It is hard to definethe term “steady land supply that meet the demand”. And the prediction of the future trend maytherefore be less powerful and can poorly support the quantitative and qualitative analysis based on it.More, it is difficult for the system to address both the cumulative and dynamic aspect of environmentalimpacts and constraints in urbanized areas. Although the responsiveness of the system toenvironmental condition can be increase by including mapping of pollution “shed” around futuretransportation and industrial concentration, monitoring land development within watershed, providingdata to estimate the cumulative impacts of development on land cover and soil permeability, research iscertainly needed in this area.ConclusionAll in all, GIT would certainly help facilitate a steady land use that meet the demand. However, justresearches and developments on GIT tools must carry on. And the problem of obtaining a completedand comprehensive database is still hard and seems impossible. Therefore, although people can use theanalysis’s result of GIT as a supportive evidence in new policy that help increase the land supply, peopleshould not fully depend on it and should do more consideration before any decision making based onthe result.
ReferencesAnne Vernez Moudon and Michael Hubner, 2000, Monitoring Land Supply with GISLillesand and Keifer, 2009, Remote Sensing and Image InterpretationInfo resources, 2007, http://www.inforesources.ch/pdf/focus07_3_e.pdf