Regional Overview of Physical Alteration and Destruction of Habitats (PADH) in the Western Indian Ocean region

The United Nations Environment Programme as the Secretariat of the Global Programme of Action for the Protection of the Marine Environment from Land-based Activities (GPA) established the GPA Coordination Office in The Hague, The Netherlands after the adoption of the GPA in Washington D.C. in 1995. The role of the GPA office, in close partnership with relevant organizations, is to coordinate promote and facilitate implementation of the tasks and activities contained in the Global Programme of Action that was adopted by 108 Governments, and the European Commission.

The GPA promotes and facilitates implementation of priority activities at the national, regional and sub-regional level through, the UNEP Regional Seas Programme; and plays a catalytic role with other organizations and institutions in the implementation of the GPA at the international level. The GPA has been mandated to provide guidance and develop activities to address nine source categories of land-based sources of marine degradation. These are: wastewater/sewage; Nutrients; Persistent Organic Pollutants; Radioactive substances; Heavy metals; Sediment mobilization; Litter; Oils (Hydrocarbons); and Physical Alteration and Habitat destruction (PADH).

Physical alteration and habitat destruction is considered as the strongest reflection of the increasing population and economic activities in the coastal zone. PADH is also referred to as “Habitat and Community Modification” by the Global International Water Assessment (GIWA) Programme or “Destruction and Alteration of Habitats” in other processes.

Based on its nature and effects, PADH can broadly be categorized into hinterland and coastal foreshore development (GESAMP, 2001). The effects of hinterland development involve mainly the modification of river basins by human activities resulting in changes, in terms of scale and periodicity of water, suspended sediments and nutrient fluxes. According to the GESAMP (2001), activities contributing to the physical alteration in the coastal foreshore include: beach development and sustenance; tourist development; the dredging of navigational channels; construction of industrial plants and infrastructure; and reclamation.

The Physical Alteration and Habitat Destruction as defined by GPA focuses on sediment mobilization effects by the four economic sectors that potentially pose a threat to such habitats. These are: tourism; ports and harbors; aquaculture; and mining (sand and aggregate extraction).

The overall PADH Project aims at supporting the efforts of stakeholders in protecting coastal and marine habitats against physical alteration and destruction. Through the project, appropriate checklists and guidance will be developed for each of the priority sectors. The project will also document and disseminate information on case studies and examples illustrating environmental, social and economic benefits of taking positive actions. Furthermore, regional stakeholder meetings will be held in South Asian, 9 Caribbean and East African regions to develop regional and sector specific checklists as well as initiating actions such as pilot projects