1. Why the marine environment needs protection from nutrients
Eutrophication can result from augmentation of nutrient inputs to coastal and marine areas as a consequence of human activities. In general, such eutrophication is usually confined to the vicinity of coastal discharges but, because of both the multiplicity of such discharges and regional atmospheric transport of nutrients, such affected coastal areas can be extensive.
The effects of the enhanced mobilization of nutrients are enhanced productivity but these can also result in changes in species diversity, excessive algal growth, dissolved oxygen reductions and associated fish kills and, it is suspected, the increased prevalence or frequency of toxic algal blooms.
2. What is the objective of the GPA in relation to nutrients ?
The objective/proposed target is:
(a) To identify, in broad terms, marine areas where nutrient inputs are causing or are likely to cause pollution, directly or indirectly;
(b) To reduce nutrient inputs into the areas identified;
(c) To reduce the number of marine areas where eutrophication is evident;
(d) To protect and, where appropriate, to restore areas of natural denitrification.
3. Which actions does the GPA suggest ?
National actions, policies and measures
Actions, policies and measures of States within their capacities should include:
(a) Identification of areas where nutrient inputs are likely to cause pollution, directly or indirectly;
(b) Identification of point sources and diffuse sources of nutrient inputs into these areas;
(c) Identification of areas where changes in anthropogenic nutrient inputs are causing or are likely to cause pollution, either directly or indirectly, and prioritization of these areas for action;
(d) Adoption of appropriate cost-effective policy instruments, including regulatory measures, economic instruments and voluntary agreements, to control anthropogenic sources of nutrients affecting these areas, including:
Activities related to sewage treatment and management mentioned in paragraph
97 (b) above;
Minimization of the release of nutrients by the use of best environmental practice
(BEP) in agriculture and aquaculture operations;
Minimization of the release of nutrients by the use of best environmental practice
(BEP), best available techniques (BAT) and integrated pollution prevention and
control (IPPC) in industrial operations;
Formulation and implementation of awareness and information campaigns for the
adoption of appropriate agricultural techniques, including balanced fertilization
and ecological agriculture, to minimize nutrient losses from agricultural activities;
Introduction of measures to reduce inputs of nutrients via atmospheric deposition
from transportation, industrial plants and agriculture;
(e) Strengthening the capacities of local authorities to take account of likely
impacts of inputs of nutrients from agriculture and urban development in carrying
out their functions of planning and controlling land-use and development;
(f) Establishment or improvement, as appropriate, of monitoring of all aspects of eutrophication;
(g) Promotion of scientific research on the suspected linkages between eutrophication and toxic algal blooms;
(h) Development and adoption of programmes to protect and, where appropriate, restore habitats acting as natural sinks for nutrients such as wetlands.
Regional actions
States within a region should cooperate in the following action:
(a) Establishment of common criteria for the identification of existing and potential problem areas including possible solutions with regard to eutrophication;
(b) Identification of marine areas in the region where nutrient inputs are causing or are likely to cause pollution, directly or indirectly;
(c) Identification of areas for priority actions;
(d) Establishment of uniform approaches to the calculation of anthropogenic nutrient inputs to the aquatic environment from agriculture and other sources, as appropriate, with the aim of improving the estimation of these inputs;
(e) Development and implementation of programmes and measures for reducing nutrient inputs from anthropogenic activities to areas where these inputs are causing or are likely to cause pollution directly or indirectly and, where the agricultural sector is a predominant source, to pay particular attention to that sector and the implementation of measures identified for it;
(f) Establishment of mechanisms for assessing the effectiveness of the measures taken to reduce nutrient inputs to the aquatic environment from both point and diffuse sources;
(g) Development of strategies for reducing eutrophication in areas already affected and those susceptible to being affected.
International actions
International actions should include:
(a) Participation in a clearing-house for providing information about best environmental practice and access to best available techniques to reduce and/or eliminate causes of anthropogenic eutrophication;
(b) Strengthening of international programmes for enhancing capacity for:
Identification of areas where inputs of nutrients are causing or are likely
to cause pollution, directly or indirectly;
Nutrient control and removal techniques;
Application of best environmental practice in aquaculture and agriculture;
(c) Cooperation with countries in need of assistance, through financial, technological
and scientific support, in developing and implementing practices which minimize
releases of nutrients to the environment, including environmentally sound land-use
techniques, planning and practices;
(d) Provision of forums for establishing criteria for determining the circumstances in which nutrients are likely to cause pollution, directly or indirectly;
(e) Maintaining existing international quality assurance and quality control procedures relevant to eutrophication.
Sediment Mobilization
1. Why the marine environment needs protection from sediment mobilization ?
Natural sedimentation and siltation are important in the development and maintenance of numerous coastal habitats. Habitats requiring sediment input include coastal wetlands, lagoons, estuaries and mangroves. Reduction in natural rates of sedimentation can compromise the integrity of these habitats, as can excessive sediment loads, which may bury benthic communities and threaten sensitive habitats such as coral reefs, mangroves, seagrass beds, and rocky substrates.
Contaminated sediments, whether they are fresh inputs or dredged, may also lead to pollution, the latter through resuspension or improper disposal.
Anthropogenic modifications to sediment mobilization and sedimentation are made by, inter alia, construction activities, forestry operations, agricultural practices, mining practices, hydrological modifications, dredging activities, and coastal erosion. Effects are generally local in nature, but transboundary implications may occur in some areas where major river systems form a common border and where littoral currents carry inputs across international boundaries.
2. What is the objective of the GPA in relation to sediment mobilization ?
The objective/proposed target is to reduce, control and prevent the degradation of the marine environment due to changes in coastal erosion and siltation caused by human activities.
3. Which action does the GPA suggest ?
National actions, policies and measures
Actions, policies and measures of States within their capacities should include:
(a) Development and implementation of environmentally sound land-use practices to control sediment discharges to watercourses and estuaries which cause degradation of the marine environment;
(b) Establishment of measures to control, reduce and prevent coastal erosion and siltation due to anthropogenic factors such as land-use, including coastal mining and construction practices, while ensuring that natural erosion supplying sedimentary habitats is not impeded;
(c) Introduction of watershed management and land-use practices to prevent, control and reduce degradation of the marine environment due to anthropogenic changes in sediment loads and contamination of sediments;
(d) Application of practices developed under existing international regulations to prevent marine pollution/degradation from dumping of dredged material and associated dredging operations;
(e) Establishment or improvement of monitoring of sediment transport to the marine environment and associated sedimentation patterns and rates;
(f) Application of environmentally sound management and storage practices for polluted dredged material;
(g) Adoption of measures to minimize changes to natural erosion, sediment transport and sedimentation resulting from the construction of barriers and barrages.
Regional actions
States within a region should cooperate in the following action:
(a) Promotion of regional cooperation, where appropriate, for the establishment of programmes and priority measures to control anthropogenic modifications to sedimentation/siltation;
(b) Development or enhancement, as appropriate, of regional programmes for the exchange of information on technology and techniques and experience regarding sedimentation/siltation.
International actions
International actions should include:
(a) Development of methodologies to reduce, control and prevent adverse effects of sedimentation/ siltation, including the formulation of mechanisms for determining changes in sediment mobilization and transport, incorporating relevant quality assurance and standardization procedures;
(b) Participation in a clearing-house for providing information on technologies, measures and experiences regarding sedimentation/siltation;
(c) Cooperation with countries in need of assistance, through financial, scientific and technical support, in the development and implementation of environmentally sound land-use techniques, planning and practices to reduce, control and prevent the negative effects of changes in erosion and siltation rates.