The status of biodiversity in Denmark reflects the country’s high population density and a long history of intensive commercial exploitation of raw materials, soils, timber, water and stocks of fish and game. The vast majority of the country is covered by highly modified urban, silvicultural and arable areas, where construction, cultivation and plantations limit biological diversity. However, there are some natural areas left with high biological diversity.

The coastal and marine ecosystems must be considered the most important Danish contribution to European biodiversity, as Denmark holds a major proportion of the areas of dunes, saltmarsh and shallow marine waters, of crucial importance for specialised lichens, plants, fungi and invertebrates, as well as fish and water birds.

The best current estimate is that biodiversity is still under heavy pressure.

Habitats in the open land are among the most threatened in Denmark, due to changes in agricultural management and practices. Since monitoring of Danish farmland birds started in 1976, the population of 22 species of Danish farmland birds has changed. Between 1990 and 2008 the population fell by 36 %.

The area occupied by open habitat types such as commons, heaths, bogs and sand dunes is decreasing and 66 % of open habitats have a poor conservation status.

The population of 22 species of Danish woodland birds increased between 1980 and 1990 and has subsequently been stable. Apart from birds, there is a lack of knowledge of the status of woodland species.

In the aquatic environment the conservation status is unfavourable for all five types of lake listed by the Habitats Directive and for one of two watercourse types. The incidence of the most sensitive of small animals in watercourses rose by 23 % between 2000 and 2007. Diversity of species and populations of seabed organisms in Danish coastal waters has fallen since 2000.

Danish red‑listed species includes 29 % of species under surveillance, which indicates there is a risk of them disappearing. Around half of the red-listed species are in forest areas.

Figure 1 (6.1.1):The populations of 22 Danish bird species found on arable land (kestrel, partridge, lapwing, common snipe, skylark, swallow, meadow pipit, blue-headed wagtail, white wagtail, whinchat, wheatear, fieldfare, lesser whitethroat, whitethroat, red-backed shrike, rook, crow, tree sparrow, goldfinch, linnet, yellowhammer and corn bunting). Source: Danish Ornithological Association.

Figure 2 (6.2.1): Developments in open habitat acreage: permanent grass (pasture, common, meadow, saltmarsh), heath, bog and sand dunes. Source: Danish National Environmental Research Institute.

Figure 3 (6.3.1): The 22 species of woodland bird in Denmark (sparrowhawk, stock pigeon, black woodpecker, great spotted woodpecker, robin, redstart, mistle thrush, garden warbler, wood warbler, chiffchaff, goldcrest, pied flycatcher, marsh titmouse, crested tit, coal tit, nuthatch, tree runner, jay, raven, chaffinch, bullfinch, hawfinch). Source: Danish Ornithological Association.

Figure 4 (6.4.2): The average number of sensitive insects (stoneflies, mayflies and caddis flies), the so-called EPT taxa, of 133 watercourse stations between 1994 and 2007. The higher the number, the greater the biodiversity. Source: Danish National Environmental Research Institute.

Figure 5 (MTR2009:6.5.1): Kattegat and two in other Danish straits. Species diversity is depicted using the Margalef Index. The higher the index figure, the greater the species diversity. Source: Danish National Environmental Research Institute.

Figure 6 (6.6.1): Numbers of red-listed species, (disappeared, critically endangered, endangered, vulnerable and near-threatened) and numbers of non-threatened species by species type. The table comprises 5 656 species. Species for which there is insufficient data are omitted. Source: Danish National Environmental Research Institute.

The main pressure on Danish biodiversity are identified to be: Urbanisation, cultivation, pesticides, eutrophication, land drainage, overgrowing, high-intensity logging in forests and plantations, former activities to straighten and dam watercourses and commercial fishing.

Arable land comprise approximately 62 % of the total area in Denmark. Besides producing food crops, these fields are home to many species of plants and animals and thus are highly significant for biodiversity. Arable land has become more homogeneous and many hedges have disappeared. Fields are on average 7 % larger than they were ten years ago.

Although the atmospheric deposition of nitrogen to the terrestrial and the aquatic environment has decreased since 1990 the critical loads for sensitive habitats, i.e. heaths, commons, raised bogs and ‘Lobelia lakes’ (after Lobelia dortmanna), have been exceeded in the monitoring period 1990-2008. Approximately 1/3 of the atmospheric deposition is from foreign sources.

Pesticide treatment has increased since 2000 and the application frequency increased by more than 50 % from 2000 (2.07 times per year) to 2008 (3.16 times per year).

The quality of the Danish forest is poor, measured in the number of old trees, dead wood and undisturbed forest. On average, dead wood in Danish forests amounts to 4.7 m³ per hectare compared to 70 m³ per hectare in natural forests. Natural forest only covers 7 % of the total forest area in Denmark. Six out of nine types of forest have been labelled as having a favourable conservation status in accordance with the EU Habitats Directive for the period 2001-2006.

Marine invasive species are particularly worrying because it is very difficult to control the prevalence of marine species. An estimated 2 656 species in Denmark are not indigenous. Of these, 63 species are invasive and a further 17 species are known as potential invaders, as they appear as invasive species in countries close to Denmark. Examples of invasive species in Denmark are the warty comb jelly (Mnemiopsis Leidyi) and the Pacific oyster (Crassostrea gigas). These species influence the biological balance in Denmark.

Figure 7 (6.1.2): Average field size in hectares (ha) in Danish agriculture. The marked drop between 2004 and 2005 was due to a change in the grant scheme allowing grants for fields as small as 0.3 ha. This resulted in the recording of such fields. Source: Danish National Environmental Research Institute.

Figure 8 (1.2.2): Frequency of pesticide application in Danish agriculture. Because the calculation method changed in 1998 and the target set for frequency of application is based on an old method, both are shown. Reference: Statistics Denmark and The Danish Environment Agency.

Figure 9 (6.7.1): Average nitrogen (N) deposition from the atmosphere on Danish land areas. The figure shows critical loads for some of the most sensitive habitats and deciduous forest. For comparison, an ordinary cereal field is fertilised with approximately 150 kg nitrogen per ha per year Source: Danish National Environmental Research Institute and the Forest and Nature Agency.

Figure10 (6.7.2): Average nitrogen (N) deposition from the atmosphere on Danish sea areas. Source: Danish National Environmental Research Institute.

Figure 11 (6.7.3): Atmospheric nitrogen deposition in kg N per ha in 2008. Based on calculation models. Source: Danish National Environmental Research Institute.

Figure 12 (1.3.1). Development in number and production area in ecological farming. Source: Statistics Denmark and the Danish Plant Directorate.

Figure 13 (6.3.2): Volume of dead wood in Danish forest in 2006, measured in m3 of dead wood per ha of forest. In comparison, a natural forest contains over 70m3 of dead wood per hectare. Source: Forest and Landscape.

Figure 14 (6.8.1): Accumulated figures for introduced species recorded in Danish natural habitats, collated according to the year of the first find. Only a small percentage of introduced species are defined as invasive (see text). Source: NOBANIS.

The target of halting biodiversity loss by 2010 will not be achieved. The best current estimate is that biodiversity is still under heavy pressure, although progress has been made in reducing pressures in some areas. Several trends in species development indicate that the loss of biodiversity in lakes and rivers has stopped. The opposite is the case for the many terrestrial environments and in the marine waters.

Denmark is party to the UN Convention on Biological Diversity targeting a significant reduction in the current rate of biodiversity by 2010. Denmark has outlined its nature conservation policy objectives in a range of documents, which are in the process of being implemented. These documents are summarised in the fourth country report to CBD (2009) and include, among other, the National Strategy on Biological Diversity (2004), the Action Plan for Biodiversity and Nature Conservation (2004-2009), the National Strategy on Natural Forests (1992-2040), the National Action plan on Alien Invasive Species (2009) and the National Strategy on Honey Bee’s (2009 – 2013).

A thorough evaluation of the impact of action plans and initiatives is provided in the fourth country report to the Convention on Biodiversity. The report is based largely on the Danish state-of-the-environment reports – part A and B.

An important initiative is the Government action plan “Green Growth” from 2009. The plan includes an environment and nature plan and a strategy for a green agricultural sector. At national level several initiatives will be implemented to strengthen the protection of the various types of nature (including dryland), plants and animals.  Included in the Green Growth” plan is economic support to establish up to 75,000 ha new nature and improved site management of private and state owned Natura 2000 sites and approx. 40,000 ha § 3 areas (meadows, heaths, mosses, grasslands, etc.) outside the Natura 2000 sites.

References

• Normander, B., Jensen, T.S., Henrichs T., Sanderson, H., & Pedersen, A.B. (red.) 2009: Nature and Environment 2009 – Part A: Denmarks environment and global challenges . National Environment Research Institute (NERI), University of Aarhus, 94 p .NERI- scientific report series, no. 750.  (in Danish/English summary) http://www2.dmu.dk/webmtr/pdf/FR750_A.pdf (15.05.2010)
• Normander, B., Henriksen, C.I., Jensen, T.S., Sanderson, H., Henrichs, T., Larsen, L.E. & Pedersen, A.B. (red.) 2009: Nature and Environment 2009 – Part B: Facts. National Environment Research Institute (NERI), University of Aarhus, 170 p. NERI- scientific report series, no. 751. . (in Danish): http://www.naturogmiljoe.dmu.dk/) (15.05.2010)
• Environment Ministry 2010. Fourth country report to CBD, Denmark (draft version). http://www.blst.dk/NR/rdonlyres/568FF605-DD03-430C-B9F3-CDCC7DF6342E/0/DRAFTCBDDenmark.pdf (15.05.2010)
• Danish Biodiversity homepage. http://www.dk-chm.dk/convention/F1117808192 (15.05.2010)
• Government (2009): Government action plan “Green Growth” – Nature, Environment and the Agriculture sector. Ministry of Economic and Business Affairs. http://www.mim.dk/Nyheder/Temaer/Groen_vaekst/ and  http://www.oem.dk/sw25353.asp