Grantee Research Project Results
2006 Progress Report: Land Use Sustainability Index for Puerto Rico
EPA Grant Number: X3832209Title: Land Use Sustainability Index for Puerto Rico
Investigators: Juncos-Gautier, Marìa
Current Investigators: Juncos-Gautier, Marìa , Gonzalez-Toro, Antonio C. , Padin, Carlos M. , Santana, Jose R
Institution: Universidad Metropolitana
EPA Project Officer: Aja, Hayley
Project Period: May 1, 2005 through April 30, 2009
Project Period Covered by this Report: May 1, 2006 through April 30, 2007
Project Amount: $287,400
RFA: Collaborative Science & Technology Network for Sustainability (2004) RFA Text | Recipients Lists
Research Category: Pollution Prevention/Sustainable Development , Sustainable and Healthy Communities
Objective:
Introduction
In August 2006, a new Principal Investigator (PI) took over the direction of the research work. Since then, the Project Team has carried out its tasks following the approved Working Plan and Time Table prepared by the new PI for Fiscal Year 2006–2007.
The aim of the project is to develop and implement an easy-to-use geographic information system (GIS) model with a land use sustainability index for the municipalities of Puerto Rico (the territorial/political planning unit in Puerto Rico), designed to help measure the impact of the advancing urban/built environment on the quality and availability of land, on ecosystems, and on water. It will also enhance the sustainability of land-use policies and plans.
To achieve the aim of the project and comply with the Working Plan and Time Table, the following research tasks were completed in the period from August 2006 to April 2007:
- A new model was defined for the research work.
- The environmental risk assessment framework was worked out for the project’s overall scientific approach.
- A tentative final list of 24 indicators was selected from an original list of 60 based on specific criteria for relevance, functionality, reliability, and quality assurance.
- 90% of the data for the indicators was obtained from a variety of sources.
- The mathematical design was finalized for the construction of the Index of Sustainable Land Use Activity (ISLA) to track the sustainability of land use in Puerto Rico.
- The above results were achieved with the feedback of stakeholders. This was obtained mostly through fruitful meetings with the project’s External Advisory Committee.
Progress Summary:
Details of Each Completed Task
The Model. Based on the aim of the project, the proposed conceptual model for the research project includes the following:
Goal. “To identify the activities at the municipal level that should be modified to help drive land use towards sustainability.”
Scenarios. Two basic scenarios were selected for analysis of land use:
- Current Land Use: Describes the present situation based on selected indicators related to key environmental stressors or relievers.
- Stressors: Factors that reduce the sustainability of land-use activities.
- Relievers: Factors that improve the sustainability of land-use activities.
- Optimal Land Use: Establishes a basic optimal (or desired) land-use scenario using measurement end points (minima and maxima) developed for each selected indicator. It is function-based on the ranking and weighting of the indicators.
Desired Product. The product desired from these two scenarios is an evaluation of how close or far a municipality is from sustainability of land use. Based on the result of the evaluation, a series of recommendations will be provided to guide municipalities toward sustainability.
Table 1. Draft Sustainability Indicators
1. Water pollution risk due to lack of sewage connection |
2. Development pressure on Rustic Land |
3. Accessibility to public natural open spaces in urban areas |
4. Solid non-hazardous waste generation per person |
5. Total recycled solid non-hazardous waste |
6. Coastal flood hazard |
7. CO2 emissions per household |
8. Release of toxic substances to the environment by industries |
9. Water consumption per household |
10. Highly valuable agricultural lands |
11. Active agricultural lands |
12. Residents who work where they live |
13. Re-population of urban areas |
14. Residents living in floodways |
15. The Socio-Economic Index |
16. Accessibility to public transportation |
17. Use of public transportation to reach work |
18. The public roads footprint |
19. Accessibility to safe drinking water |
20. Approved Municipal Land Use Plan |
21. The Fiscal Fragility Index |
22. Land officially protected by the government |
The selection of each indicator is based on the following characteristics:
- Maturity (reliable data source, used before).
- Relevance (relevance and functionality for land-use planning at the municipal level).
- Multiple use (available and adaptable for different scales, scenarios).
- Capability of evaluating the current situation and future tendencies.
- Quantitative and qualitative value.
Once the group of indicators has been selected, their values as stressors or relievers are to be translated into an equation to define the land use sustainability index. Each indicator is to be weighted in terms of present sustainability:
Low Sustainability--------High Sustainability
The equation for the index will measure the combined behavior of the indicators.
Figure 1. Schematic Overview of the Proposed Model
Practical Use and Applicability. The purpose of developing the land use sustainability index is to provide an easy-to-use and, at the same time, scientifically sound tool to guarantee its practical use and applicability in decision-making at the municipal and community level. So designed, the project is more likely to achieve a positive impact on sustainability in Puerto Rico and the region. This is a groundbreaking project for Puerto Rico. It is the first time that relevant data will have been compiled and studied for the development of a land-use index. Further areas of research will be recommended in the Final Report to enhance the model and its scientific base and to increase its scope for public policy.
Use of Science
The overall scientific work of the project has been defined and involves an environmental risk assessment framework. This includes:
- The collection, organization, and analysis of available and reliable data and information in Puerto Rico for evaluation of the impact of different environmental stressors related to land use on the quantity and availability of land, ecosystem, and water.
- The proposal of a conceptual model to develop a land use sustainability index based on: (1) two basic scenarios, the present or current situation and the desired or optimal situation for land use; and (2) measurement endpoints using indicators as environmental stressors or relievers whose minimum to maximum range is based on the scientific definitions of these. The model will also involve:
- Evaluation of the relationship between the stressor or reliever levels and their ecological effects (which may be positive or negative).
- Use of the GIS for geoprocessing in generating derived data sets and in modeling. This will include line distance modeling, spatial analysis, and cluster analysis in building some of the indicators.
- Statistical analysis of measurable results, specifically correlation analysis to reduce any possible distortion of the model, due to redundancy or the absence of key indicators, and regression analysis for a quantifiable result (the land use sustainability index).
- Four case studies. The model uses four municipalities in Puerto Rico as case studies to establish the parameters that will be used later for other municipalities on the island; these municipalities represent different island landscapes and regions.
- The analysis involving selection, evaluation, and validation of the indicators using published research studies, available quantifiable data sources in different government agencies, and interviews with local scientists and informed stakeholders to provide for the scientific soundness and relevance of the indicators to the purposes of the project and the environmental circumstances of a densely populated Caribbean island. In addition, other qualitative, social, economic, and political factors are being taken into account in the analytical process.
- The process of risk characterization to develop the sustainability index, which will summarize and integrate quantitative and qualitative expressions of risk, for which explanatory text will be provided to facilitate decisionmaking and public policy recommendations on land use.
- Outreach and public policy, for which the project has an Advisory Committee of informed stakeholders to provide guidance and recommendations and to validate the above process. The committee includes 13 local municipalities which have participated consistently (including the four municipalities collaborating in case studies) as a sample of Puerto Rico’s 78 municipalities, as well as representatives of key commonwealth and federal government agencies involved in implementing public policy.
The Indicators
Most of the research work on the last 4 months has focused on identifying and validating possible data resources for the indicators. Of the original 60+ indicators, a final list of 24 was selected based on their functionality, reliability, and relevance to the territorial unit (the municipality) and the aim of the project (sustainability of land use). By April 2007, the Project Team has compiled over 90% of the necessary data for each of the 24 selected indicators.
It is important to note the challenges that the Project Team has encountered in the identification and validation of data sources:
- There are no data for some potential indicators, so these have been eliminated from the preliminary list of indicators.
- There are no metadata for many data sets, so the team will have to address the reliability of some existing data sets during 2007.
- Information is sometimes not available in digital form but distributed in documents in several government agencies, so that it takes longer than expected to gather and analyze.
- The best available land inventory for Puerto Rico is over 25 years old.
- The municipalities have not developed a scientifically sound method to calculate developable land for urban expansion. Our land use sustainability index will be a major contribution in this area.
These difficulties have been overcome in two ways: (1) by locating the information sought in certain indicators, and (2) by selecting other indicators, for which data is more readily available and more reliable, that are able to measure the required activity.
In addition, the model will have to take into account dissimilar conditions across municipalities. So work is being done during 2007 to establish the geographic and socioeconomic contexts of the four municipalities that were chosen as case studies to define the application of the sustainability index for each municipality better. This is important since each selected indicator can vary substantially as stressor or reliever based on the geographic and socioeconomic context of each locality.
The Mathematical Model for the Index
For the mathematical model, land-use indicators will be grouped as stressors or relievers as described in the model. This grouping does not exclude the possibility of creating four separate indexes summing up the behavior of the indicators based on the four categories into which they have been also divided: environmental, socioeconomics, infrastructure, and institutional. The design of the equation will allow for this possibility, and the team has it under consideration.
The Stressors Index (STI)
Each of the stressor indicators is designated by a lower case letter x. There will be n stressors identified as:
x1, x2, x3, ……, xn
For example, x1 may be the amount of non-toxic solid waste per household per year in the given municipality.
For each of the stressors, the Project Team will define a benchmark representing a worst-case value for that particular indicator. For example, suppose that 1.5 tons of solid waste per household per year is the benchmark (any amount that high or higher is a worst-case scenario for the municipality regarding solid waste generation).
Each stressor will be divided by its benchmark and multiplied by 100 to produce an indexed value for the stressor that will be designated with an upper case letter X. The indexed value will range between 1 and 100. There will then be a list of n indexed stressors identified as:
X1, X2, X3, ……, Xn
The n indexed stressors will then be combined into the STI, as follows:
STI = X1αX2βX3γ, …Xnζ
The exponents α, β, γ ,…ζ are weights to be assigned by the Project Team to each of the indicators. If all were to be equally weighted, the exponent in each case would be 1/n; however, the Project Team will generally assign different weights to the various stressors.
The STI can take on values ranging from 1 to 100. A value of 100 means that each of the n stressors has reached or passed the benchmark, which is the worst possible state for the municipality in question. A value of one means that each of the individual stressors is entirely absent, which is an unattainable ideal state.
The Relievers Index (RI)
Each of the reliever indicators will be designated by a lower case letter y. There will be m relievers identified as:
y1, y2, y3, ……, ym
For example, y1 may be the percentage of forested land in a given municipality.
For each of the relievers, the Project Team will define a benchmark representing a best-case value for that particular indicator. For example, suppose that 50% forested land is the benchmark (any amount that high or higher is a best-case scenario for the municipality regarding forest cover).
Each reliever will be divided by its benchmark and multiplied by 100 to produce an indexed value for the reliever that will be designated with an upper case letter Y. The indexed value will range between 1 and 100. There will then be a list of m indexed relievers identified as:
Y1, Y2, Y3, ……, Ym
The m indexed relievers will then be combined into the RI, as follows:
RI = Y1αY2βY3γ, …Ymζ
The exponents α, β, γ,…ζ are weights to be assigned by the Project Team to each of the indicators. If all were to be equally weighted, the exponent in each case would be 1/m, however, the Project Team will generally assign different weights to the various relievers.
The RI can take on values in the range 1 to 100. A value of 100 means that each of the m relievers has reached or passed the benchmark, which is the best possible state for the municipality in question. A value of one means that each of the individual relievers is entirely absent, which is the worst possible state.
The Index of Sustainable Land-Use Activity (ISLA)
The RI and the STI will be combined into a single index to measure sustainability, as shown below:
Multiplication by 100 and taking the square root are mathematical transformations designed to generate an easy-to-read scale for the index. As designed, the index can take on values between 1 and 100. A value of 100 is the best-case state, while a value of 1 is the worst-case state.
Figure 2.
A value of 10 happens when the STI and RI have the same value, in which case they cancel each other out. For readings below 10, the STI is larger than the RI and ISLA is stressor-dominated. For values higher than 10, ISLA is reliever-dominated. A reading of 10 is a stalemate marking the threshold between sustainability and unsustainability. The above diagram presents the proposed interpretation of possible ISLA values.
References:
Ambiente Italia Research Institute. European common indicators, toward a local sustainability profile. Ambiente Italia, Milan, 2003.
Bernal C, y Cruz Baez JF, David A. Puerto Rico. Madrid: Ediciones Anaya, 1988.
Department of Natural and Environmental Resources. Plan Integral de Recursos de Agua de Puerto Rico (Draft) [Master Plan for Puerto Rico’s Water Resources]. Water Plan Office, Department of Natural and Environmental Resources, San Juan, Puerto Rico, 2007.
Department of Commerce. Census of population; Puerto Rico. Washington, DC: Bureau of the Census, 2000.
Department of Natural and Environmental Resources. Guias de reforestacion para las cuencas hidrograficas de Puerto Rico [reforestation guidelines for Puerto Rico watersheds]. San Juan, Puerto Rico, 1997.
Department of Transportation and Public Works (DTPW). La Planificacion Estrategica del Departamento de Transportacion y Obras Publicas y de la Autoridad de Carreteras y Transportacion [Strategic planning of the Department of Transportation and Public Works and the Transportation and Highways Authority]. San Juan, Puerto Rico, 2003.
Hak T. Sustainability indicators, a scientific assessment. Washington, DC: Island Press, 2006.
Land Use Plan Office. Plan de uso de terrenos de Puerto Rico: perfil regional. Borrador preliminar [Puerto Rico land use plan: regional profile. Preliminary draft]. San Juan, PR: Puerto Rico Planning Board, 2006.
Lopez T del M, Martinuzzi S. What is the urban cover of Puerto Rico? Rio Piedras, PR: USDA Forest Service, International Institute of Tropical Forestry (in preparation, 2007).
Lopez T del M, Aide TM, Thomlinson JR. Urban expansion and the loss of prime agricultural lands in Puerto Rico. Ambio 2004;30:49-54.
Mainka S, McNeely J. Depend on nature, ecosystem services supporting human livelihoods. IUCN-The World Conservation Union. Campiche, Italy, 2005.
School of Environmental Affairs, Metropolitan University. Puerto Rico en ruta hacia el Desarrollo Inteligente [Puerto Rico’s road to smart growth]. San Juan, PR: Center for Sustainable Development Studies, 2001.
Severino, CE. Los procesos de urbanizacion y metropolizacion de San Juan: Factores principales del consumo de espacio y de la configuracion territorial de la sociedad puertorriquena [The Urbanization and Metropolization of San Juan: Principal Factors in the Consumption of Space and Land Configuration in Puerto Rican Society]. Futuro economico de Puerto Rico. San Juan, PR: University of Puerto Rico Press, 1999.
The Working Group on Climate Change and Development. Up in smoke? Latin America and the Caribbean, London: nef, 2006.
United Nations Environment Programme. Environmental indicators for North America. Canada: Earth Print, 2006.
United Nations Environment Programme. Planet in peril, an atlas of current threats to people and the environment. Paris: UNEP/Grid-Arendal, 2006.
United Nations Environment Programme. Geo Year Book 2007. Canada: Earth Print, 2007.
United Nations Human Settlements Programme. State of the world’s cities 2006/7, the millennium development goals and urban sustainability: 30 years of shaping the habitat agenda. London: Earthscan, 2006.
Supplemental Keywords:
RFA, Scientific Discipline, Ecosystem Protection/Environmental Exposure & Risk, Sustainable Industry/Business, cleaner production/pollution prevention, Monitoring/Modeling, Environmental Monitoring, Urban and Regional Planning, sustainability assessment, ecosystem management model, land use model, urban planning, watershed, developmental stability, geo-spatial internet system, conservation, water supply, GIS, ecological models, pollution preventionProgress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.