GIS for Coastal Zone Management - Chapter 18

CHAPTER EIGHTEEN Applying the Geospatial Technologies to Estuary Environments David R. Green and Stephen D. King 18.1 INTRODUCTION Around the World the value and vulnerability of estuaries has long been recognised. The National Estuary Study of 1969 in the U.S. is just one such example (http://www.inforain.org/mapsatwork/oregonestuary/Oregonestuary_page 4.htm). In the UK, initiatives by English Nature (EN) and Scottish Natural Heritage (SNH) to develop new approaches to estuary management in England and Wales, and Scotland respectively, led to Estuary Management Plans (English Nature, 1993). In Australia there have also been many similar initiatives to develop sustainable management of estuarine environments increasingly coming under pressure from tourism and industry (NLWRA, 2002) and, more recently, in the UK, from the impact of offshore windfarms e.g. Robin Rigg in the Solway Firth (Anonymous, 2003). Green (1994; 1995) proposed the idea of GIS-based estuary information systems in the UK as a means by which it would be possible to collect, store, analyse and display spatial data and information to aid in estuary management. At the time, GIS was just beginning to develop into a practical tool for environmental applications in coastal zone management. In the intervening years, a great deal of interest has been shown in the development of GIS and the related geospatial technologies to aid in environmental monitoring, mapping, modelling, and management. Rapid developments in information technology (IT), including the Internet and the related technologies, have also led to the more widespread use of geospatial data and information for environmental applications by coastal managers and practitioners. Such developments have been responsible for providing the basis for access to data and information for management and public participation exercises. Increasingly, decision support systems (DSS) and information systems are also being used to support data and information requirements for coastal management. With the continuing evolution of Information Technology (IT), the collection of, and access to, both data and information have rapidly been extended to the use of mobile technologies. These include Personal Digital Assistants (PDAs), Wireless Application Protocol (WAP)-enabled mobile phones, Global Positioning Systems (GPS), digital still and video cameras, and mobile GIS products such as ESRI`s ArcPad, PocketGIS (http://www.posres.com), HandyGIS © 2005 by CRC Press LLC (http://www.handgis.com) and FastMap (http://www.surveysupplies.com). Field data collection and access to information, via remote uploading and downloading, sending email attachments (e.g. photographs taken with a digital still camera or camera accessory for a mobile phone), and accessing the Internet using wireless technology are now all providing new opportunities to collect, work and interact with spatial data ‘on-the-fly’ (e.g. Vivoni and Camilli, 2003). Alongside the hardware and software developments there have also been a number of new and important airborne and satellite-borne sensors. These have provided new sources of finer spectral and spatial resolution data to assist in the monitoring of coastal and estuarine environments e.g. CASI (Compact Airborne Spectrographic Imager), whilst LiDAR (Light Detection and Ranging) data provides unique high-resolution height data. The launch of ENVISAT in 2002 by the European Space Agency (ESA) for dedicated environmental monitoring, and European projects such as COASTWATCH (http://www.coastwatch.info) are also increasing awareness of the role of EO data for coastal monitoring in the context of GMES (Global Monitoring of Environment and Security). This chapter presents an overview of some of the recent developments in the application of the geospatial technologies to estuary environments as the basis to support growing requirements for data and information in the context of environmental monitoring, mapping, and management. The role of some of the different geospatial technologies for environmental data collection, processing and access to information is examined. To conclude, some future developments are discussed. The chapter is illustrated using a number of examples drawn from Europe (including the UK), North America, and Australia. 18.2 THE ESTUARY ENVIRONMENT Estuaries are very well studied features of our coastal environment. A great deal of research has been undertaken into the physical processes operating in an estuary including sediment movement, water circulation, pollution and erosion (e.g. Stapleton and Pethick, 1996; Stove, 1978; Townend, 2002). The use of modelling techniques has been widely applied in an attempt to increase our knowledge and understanding about the processes that are active (e.g. Hinwood and McLean, 2002). Ecological studies of estuarine environments have included investigations into coastal habitat, macro-algal weedmats, and bird population distribution (e.g. Jernakoff et al., 1996; Young et al., 2000; Lewis and Kelly, 2001; Ripley et al., 2002). Estuaries are complex and highly productive ecosystems (among the most productive on Earth) supporting a wide range of habitats and species, extending from the river`s upper tidal limit to the sea, and provide a constantly changing environment where sea and fresh water mix. They provide: x Habitat (live and feed) x Nursery Areas (reproduce and spawning) x Productivity (abundance and biodiversity) x Water Filtration (fresh and salt marshes) x Flood Control (buffer to flood waters, dissipate storm surges) © 2005 by CRC Press LLC x Erosion Prevention and Stabilisation (grasses and plants) x Cultural Benefits (recreation, scientific knowledge, education, aesthetic value) x Economic Benefits (natural resources used for recreation, industry, fishing, tourism) (http://inlet.geol.sc.edu/nerrsintro/nerrsintro.html and http://www.epa.gov/owow/estuaries/about1.htm) Many different habitat types, for example, are found in and around estuaries (http://www.epa.gov/owow/estuaries/about1.htm) including: x Shallow open water x Freshwater and salt marsh x Sandy beaches x Mud and sand flats x Rocky shores x Oyster reefs x Mangrove forests x River deltas x Tidal pools x Sea grass and kelp beds x Wooded swamps These are home to an abundance and diversity of wildlife including: x Shore birds x Fish x Crabs and lobsters x Marine mammals x Clams x Shellfish x Marine worms x Sea birds (http://www.epa.gov/owow/estuaries/about1.htm) Estuaries are also multi-value resources to society (NWLRA, 2002). They provide a whole suite of human resources, benefits and services (http://www.epa.gov/owow/estuaries/about1.htm). Such environments support commercial, traditional, and recreational fisheries, tourism, and wilderness experiences. They have also long been a source of inspiration for the human mind through aesthetics, art, and poetry. Since early times estuaries have been places for human settlement, providing sheltered harbours, transport and trade routes and natural resources for industry (http://www.iwight.com). Some are still relatively sparsely developed whilst others have become densely populated areas. Not surprisingly the wide range of potential uses results in many conflicts, and therefore necessitates a management strategy. Each estuary has its own distinct characteristics, susceptibility to impacts, and management requirements. An © 2005 by CRC Press LLC increasing number of national and international designations, policy and bylaws also make management of an estuary environment potentially very complicated. Worldwide there is now a wide range of organisations with statutory responsibilities on land, sea, and across the intertidal zone. In addition, there are many coastal and estuary management plans (http://www.iow.gov.uk) designed to provide a more holistic approach to sustainable management of coastal areas. As local, national and international interest in estuaries has grown, so too have the sources of information available to managers and the public. Besides documents such as estuary management plans, there are now many local community groups who seek to involve and inform the public about estuaries. In the UK, for example, there are a number of organisations who look after the interests of the local estuary communities; for example, the Thames Estuary Partnership, the Solway Firth Partnership, the Moray Firth Partnership, and the Forth Estuary Forum to mention but a few. Besides providing documentation in the form of management plans, papers and publicity, these groups are also increasingly actively involved with local communities through the development of websites, online mapping and various local activities e.g. litter monitoring, habitat surveys, field visits and seminars. In other parts of the world, for example the US and Australia, there are similar approaches to estuary management. For example, in Australia: the site http://www.dlwc.nsw.gov.au/care/water/estuaries/Inventory/Index_Geogr.html, and in the USA the sites http://www.spn.usace.army.mil/bmvc/baylink.html and http://www.estuaries.gov/about/programs.html provide lists of national programs and organisations involved in estuaries and resources. A number of recent projects have also focused on the status of Australian estuaries. For example, Australia`s Near Pristine Estuaries: Assets Worth Protecting (NLWRA, 2002) has made a preliminary classification of all of Australia`s estuaries based on their `condition.’ 18.3 ESTUARY MANAGEMENT Estuaries are clearly very complex, interesting, and dynamic components of coastal zones around the World. They provide an interface between freshwater and saltwater environments, one that is constantly changing. They are also fragile environments and easily affected by human activities whether it be settlement, industry or tourism. Changes, however small, can be very harmful to the survival of an estuary (http://estuaries.gov/about/aboutestuaries.html). With growing numbers of people settling and utilising estuaries, there are many activities that are now considered to endanger the survival of estuaries; such as dredging, the infill of flats and marshes, pollution, reconstruction of shorelines for housing, transportation, and agricultural needs. Also, marinas and tidal barrages can lead to dramatic changes in water circulation, erosion, and sediment movement. The effects of changes that have taken place have been unsafe drinking water, closure of beaches and shellfish beds, the development of harmful algal blooms, unproductive fisheries, loss of habitat and wildlife, and fish kills, as well as a host of other human health and natural resource problems (http://www.epa.gov/owow/ estuaries/about1.htm). Addressing such problems involves the use of planning, protection measures, and the implementation of © 2005 by CRC Press LLC management strategies. The protection of estuaries from detrimental change is considered vital in order to preserve natural ‘beauty and bounty,` as well as to sustain livelihoods that depend upon fishing and tourism. The designation of protective zones, use of patrols and enforcement can be used, whilst management, for example, can help to restore estuaries (http://www.estuaries.org). But estuaries are often difficult areas to manage successfully because of all the conflicting interests that exist. Whilst local partnerships between communities, industry and government can be, and have been, very helpful in addressing some of the problems facing estuarine environments (for example, the Scottish Firths initiative e.g. the Forth Estuary Forum) the many competing interests are often very difficult to accommodate satisfactorily. Ideally for management to be successful requires the identification of a lead organisation at a higher level. National policy in Australia, for example, is still deemed essential despite the local and regional initiatives. But, the piecemeal approach to coastal management that seems to have developed around the World has also led to many problems. As noted by Brown (1995), “the current coastal management system is the cause of the failure to redress the problem of the coastline. This management system is characterised by fragmentation of responsibility between spheres of governments, among different professional areas of expertise, and across different social, economic and environmental interests. It is indeed difficult for the existing systems of coastal management to become part of the solution to coastal degradation while it remains part of the problem.” 18.4 GEOGRAPHY AND THE GEOSPATIAL TECHNOLOGIES Geospatial technology has the potential to assist in the future management of estuarine environments in a number of ways. Brown (personal communication, 2003) considers GIS, for example, to have multiple roles including record keeping, monitoring change, advising scientists, and most crucially (and currently the least developed) for demonstrating relationships between biophysical systems and socio-political options. The rationale for using geospatial technologies in a coastal environment is also clearly highlighted by Fabbri (1998) in the following quote: “Given the complexities of coastal systems and the multidisciplinarity required for sustainable coastal development, computerized systems are necessary for the integration and distribution of vast amounts data and expert knowledge. They are also vital for performing analyses to aid decision makers in their difficult task of proving optimal and compromise coastal management solutions” In this chapter, ‘geospatial technologies’ are considered to include remote sensing (aerial photography, airborne and satellite data and imagery), Geographical Information Systems (GIS), Global Positioning Systems (GPS), mobile computing e.g. portable computers and Personal Digital Assistants (PDAs), WAP-enabled mobile telephones, digital still and video cameras, portable data storage and compression, and the Internet. Together these technologies are all rapidly becoming increasingly useful tools for a wide range of environmental projects that have a requirement for data collection and access to digital spatial data and © 2005 by CRC Press LLC ... - tailieumienphi.vn