D1 Biological Diversity
Biological diversity is maintained. The quality and occurrence of habitats and the distribution and abundance of species are in line with prevailing physiographic, geographic and climatic conditions.
Descriptor 1 of the MSFD is providing a definition of Good Environmental Status in relation to biological diversity. This equates to a state where there is no further loss of diversity, the deteriorated attributes of biological diversity are restored and the use of the marine environment is sustainable. The assessment of state is required at three main ecological levels: species, habitats and ecosystems.
The definition is in line with the objectives of the EU biodiversity strategy to 2020 and its implementation is directly linked to the Birds and Habitats Directives. Indirect links exist with other environmental policies tackling pollution from various sources (e.g. Water Framework Directive, the Habitats Directive, Birds Directive), the Common Fisheries Policy (CFP) and the new EU regulation on Invasive Alien Species (IAS).
© Fotolia, Author: Christian Colista
According to the Marine Strategy Framework Directive (MSFD), biological diversity should be maintained. Specifically, the quality and occurrence of habitats and the distribution and abundance of species are in line with prevailing physiographic, geographic and climatic conditions. The Directive covers the whole range of species, habitats and associated pressures in all European marine regions (from coastal waters to open seas). The COM Decision sets certain criteria and indicators to define Good Environmental Status (GES) on species, population, habitat and ecosystem level. It is widely recognized that there are links between D1 (biodiversity per se), D4 (food-webs) and D6 (sea-floor integrity) and these are frequently referred together as the 'biodiversity theme' since the data and information requirements for these Descriptors overlap to a considerable degree, although there are separate description of what GES is for each one of them. It is also recognized that although aspects of these Descriptors are, to some extent, already addressed by other EU pieces of legislation the MSFD implementation requires further scientific and technical developments to better set the conceptual frame of biodiversity, define GES, set meaningful targets and achieve an operational capacity for a meaningful monitoring and assessment.
D1 criteria on good environmental status of marine waters. Species groups of birds, mammals, reptiles, fish and cephalopods (relating to Descriptor 1)
D1C1 – The mortality rate per species from incidental by-catch is below levels which threaten the species, such that its longterm viability is ensured.
D1C2 – The population abundance of the species is not adversely affected due to anthropogenic pressures, such that its long-term viability is ensured.
D1C3 – The population demographic characteristics (e.g. body size or age class structure, sex ratio, fecundity, and survival rates) of the species are indicative of a healthy population which is not adversely affected due to anthropogenic pressures.
D1C4 – The species distributional range and, where relevant, pattern is in line with prevailing physiographic, geographic and climatic conditions. Member States shall establish threshold values for each species through regional or subregional cooperation.
D1C5 – The habitat for the species has the necessary extent and condition to support the different stages in the life history of the species.
Pelagic habitats (relating to Descriptor 1) Criteria, including
D1C6 – The condition of the habitat type, including its biotic and abiotic structure and its functions (e.g. its typical species composition and their relative abundance, absence of particularly sensitive or fragile species or species providing a key function, size structure of species), is not adversely affected due to anthropogenic pressures.
According to the TG1 report:
Descriptor 1: "Biological diversity is maintained. The quality and occurrence of habitats and the distribution and abundance of species are in line with prevailing physiographic, geographic and climatic conditions". See Sections 0 and 2.1.
Biological diversity, in accordance with the Convention on Biological Diversity (CBD, 1992), is defined as 'the variability among living organisms from all sources including, inter alia, [terrestrial,] marine [and other aquatic ecosystems] and the ecological complexes of which they are part; this includes diversity within species, between species and of ecosystems'.
Maintained equates to:
a) no further loss of the diversity within species, between species and of habitats/communities and ecosystems at ecologically relevant scales,
b) any deteriorated attributes of biological diversity are restored to and maintained at or above target levels, where intrinsic conditions allow (cf. Art. 1.2a) and
c) where the use of the marine environment is sustainable.
The term 'habitat' in this Descriptor addresses both the abiotic characteristics and the associated biological community, treating both elements together in the sense of the term biotope (COM DEC 2010/477/EU), whereas 'quality', 'occurrence', 'distribution', 'extent' and 'abundance' form the basis of the criteria standards used to assess GES.