A WebGIS and geodatabase for Florida's wetlands

Abstract

Florida's wetlands are impacted by agricultural, urban, and other human activities. This enrichment effect can be seen in many subtropical freshwater wetlands in Florida, most notably in the Everglades. Given the environmental and political interest in these wetlands, there is urgent need for a centralized repository and mechanism to share geospatial data, information and maps of Florida's wetlands and adjacent agricultural ecosystems. Our objective was to develop an interactive WebGIS and geodatabase for Florida's wetlands providing map and data services. We used ArcIMS, a commercially available software, which was extended using a MSAccess database, Java, Visual Basic and Active Server Pages to customize our application. Our Web-based tool facilitates to share data globally, provide end-users a cost-saving solution to access up-to-date spatial datasets customized for a specific topic to users with limited GIS knowledge.

Staff from state and regional agencies and others are making increased use of our Web-tool to assist in the decision-making process to restore and preserve wetlands in Florida. Our interactive website of Florida's wetlands is accessible at http://www.giswetlands.ifas.ufl.edu.

Introduction

Geographic information technology enables the integration of geospatial datasets of land and water resources and facilitates data sharing via the Internet as outlined in the National Spatial Data Infrastructure (Clinton, 1994), a concept defined as the technologies, policies, and people necessary to promote sharing of geospatial data throughout all levels of government, the private and nonprofit sectors, and the academic community. This concept can be profitably applied to wetland ecosystems. Wetlands are endpoints of hydrologic and nutrient flow patterns accumulating nutrients and contaminants from upland agricultural and urban ecosystems. In the Greater Everglades ecosystem, wetlands form a critical interface between uplands and adjacent water bodies and act as a buffer for retention of phosphorus (P). The subtropical climate, high annual precipitation rates, sand-rich soils, and karst topography cause accelerated transport of nutrients and contaminants into wetlands. Given the environmental and political interest in these wetlands, there is urgent need for a centralized repository and mechanism to share geospatial data, information and maps of Florida's wetlands and adjacent agricultural ecosystems.

Like many other rapidly evolving information technologies there is confusion about the consistent use of terminology when addressing the sharing of geospatial datasets “online” such as Internet GIS (Peng, 1999), GIS online, Distributed Geographic Information (Plewe, 1997), Web-based GIS, or simply Web GIS (Grunwald et al., 2003). Terms are similar but have different meaning. Internet GIS refers to the use of the Internet as a means to exchange data, perform GIS analysis, and present results, whereas Web-based GIS refers to the use of the World Wide Web, i.e., the WWW or the Web. Both Internet GIS and Web-based GIS use the client/server computing model. However, the term Internet has a broader and more enduring meaning than Web-based GIS, because it is any network composed of multiple, geographically dispersed networks connected through communication devices (Hall, 1994). The WWW is a networking application supporting a HyperText Transfer Protocol that runs on top of the Internet (Peng and Tsou, 2003). In other words, the Internet is an infrastructure that hosts many applications including the WWW. Distributed GI refers to the use of Internet technologies to distribute geographic information in a variety of forms, including maps, images, datasets, spatial analysis operations, and reports. Distributed GI is the most encompassing framework including both Internet GIS and mobile GIS (e.g. pocket PCs with wireless connections). Peng and Tsou (2003) points out that a WebGIS is a GIS distributed across a computer network to integrate, disseminate, and communicate geographic information on the WWW. We adopt their definition in this paper.

Commercial desktop GIS softwares such as ArcGIS (ESRI Inc., Redlands, CA) are costly and require extensive training and high-end hardware to get reasonable performance. In contrast, WebGIS provides end-users a cost-saving solution to access up-to-date spatial datasets and information (Horanont et al., 2002, Painho et al., 2001). A WebGIS is designed with tools and features that are common on Web pages and it is therefore easy to understand for users familiar with the Internet (Nelson, 2002). Other advantages of WebGIS include independence of platforms and operating systems. Usually only a simple Web browser is used to establish a client/server connection. Furthermore, WebGIS can be customized to provide specific data and information and/or services to end-users. In this paper we present a WebGIS application customized for Florida's wetland ecosystems. Two distinct types of WebGIS can be distinguished, data services and map services. Data services allow clients to retrieve spatial data and information from the Internet to local machines. Using the Internet, the latest version of the dataset is accessible to all users immediately when the datasets are updated on the central Web server (Theseira, 2002). In contrast, map services are constrained to online use and no data or information can be retrieved to local client machines.

Currently, the sector of WebGIS and Distributed GIServices are growing exponentially. Examples include, the Florida Seminole County Watershed Atlas (http://www.seminole.wateratlas.usf.edu/help/aboutcontent.asp), the Southern California Wetlands Recovery Project Information Station (http://www.eureka.regis.berkeley.edu/wrpinfo/), the Clinch River Environmental Restoration Program (CRERP) (http://www.research.esd.ornl.gov/CRERP/SUB/INDEX.HTM), and the Florida Geographic Data Library (FGDL) (http://www.fgdl.org/). Though numerous Florida specific Web-tools have been developed none is specific to Florida's wetlands which cover approximately 50% of Florida's total area. Our objective was to develop an interactive Web-based tool to integrate and visualize geospatial data and information of Florida's wetlands providing map and data services to end-users. Our Florida Wetland WebGIS provides a centralized repository of soil and environmental datasets that support the documentation of ecosystem quality in Florida's wetlands and adjacent agricultural lands.