While global warming was previously considered only as an aggravating factor in biodiversity loss, it is now recognized in the 2019 assessment report of the Intergovernmental Scientific and Policy Platform on Biodiversity and Ecosystem Services (IPBES) as a major determinant. Researchers estimate that it poses an increasing risk to biodiversity and ecosystem services (such as carbon storage, water purification, pollination, food supply, etc.).
Ecosystem-based adaptation is often an attractive choice. It includes various ways of working with biodiversity to make cities, coastlines, river basins, forests etc. more resilient to the impacts of climate change. Some examples: reforestation of slopes, creation of natural flood retention areas, agroforestry, green corridors for cities, etc.
About 20-30% of animal and vegetable species would be at increased risk of extinction if the average global temperature were to rise by more than 1.5-2.5° C.
Climate change is exacerbating the threats to biodiversity (such as habitat fragmentation and destruction, pollution, overexploitation and even biological invasions) by affecting:
Many European plant and animal species have already altered their ranges in response to climatic changes that have already occurred. Many warm-weather species are moving north. The presence and number of species originating from hot to temperate climates have increased over the last few decades in Belgium.
The effects of climate change may be conducive to certain pests (proliferation of ticks, pine processionaries, etc.).
At the same time, certain species present in Belgium will be moving further north.
The pace of climate change is, however, outstripping the ability of many species to adapt and migrate, particularly where species are prevented from moving by habitat fragmentation or cannot find suitable habitats.
The temperature rise is advancing certain Spring events, such as the opening of buds, and delaying Autumn events, such leaf-colour change. The pollen season starts earlier in Europe and lasts for longer than was the case 50 years ago.
In general, migratory birds are arriving earlier due to the increasingly frequent warm winters.
Phenological changes caused by climate change could pose a threat for biodiversity by changing how species interact (this is the case, for example, of the European Pied Flycatcher: the arrival date of this migratory species has not kept pace with the earlier emergence of the principal food for its chicks).
Climate change may disrupt the interaction between species (competition, predation, parasitism, pollination, commensalism, etc.), but also generate new interrelationships. Threats posed for individual species are often exacerbated by changes to interspecies interactions, particularly in the case of so-called specialised species. The arrival of new species adapted to the new climatic conditions may pose a threat to the structure of the existing ecosystems and the services they provide.
Invasive species are plant or animal species that have been introduced by humans outside their area of origin and which have spread in such a way that they pose a significant threat to biodiversity. Some of them cause public health problems and the costs associated with their impacts and management are significant.
The ability of species to settle and develop in a new territory is highly dependent on climate. Climate change therefore influences biological invasions by modifying the mechanisms of species transport and introduction, allowing new species to establish and modifying the distribution and impacts of existing species. In addition, climate change is also expected to impact the effectiveness of control strategies.
Climate change amplifies food safety risks and contributes to a decline in habitat quality.
A number of mutually complementary measures have been taken in Belgium, including:
– Establishing a network of protected areas (Natura 2000) by the three Regions, and at Federal level for the marine environment. 255 special protection areas have been designated for the purposes of the Birds Directive and 281 special conservation areas for the purposes of the Habitats Directive, making a total of 310 Natura 2000 sites and corresponding to a total surface area of 5 163 km2 (EU-barometer Natura 2000 – 2019).
– Establishing a (partial) classification of the species present in Belgium based on their climate needs (bioclimatic classification of species).
– Combating fragmentation (e.g. blue and green network in the Brussels region, defragmentation of rivers (dams and locks), grants in Wallonia for the planting and maintenance of indigenous hedgerows, orchards and rows of trees, components of the ecological network, etc.
– Implementing a common approach to preventing the introduction of invasive species and limiting their propagation.
– Strengthening agricultural biodiversity (through agri-environmental measures).
– Diversifying species to improve resilience to climate change (forests, green spaces, etc.).
– Monitoring the effects of climate change on biodiversity.
– Developing (and mapping) an economic assessment of ecosystem services
– The project ‘Coastbusters’ (2017 – 2020 ) test different innovative ecostem based solutions to protect the coast.
Biodiversity in towns is the focus of particular concern. The “greening” of towns: the green transformation of towns has been the subject of a study on how to meet the challenges presented by climate change. The findings of that study were published in a brochure (‘Investeer in groen – winst verzekerd’ [Invest in green – a guaranteed return]).
IPCC: Special report “Climate change, desertification, land degradation, sustainable land management, food security, and greenhouse gas fluxes in terresterial ecosystems’ (2019)
IPBES (Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services): Global Assessment Report on Biodiversity and Ecosystem Services (2019)
The online tool BiodiversiTree helps companies to define actions in favor of biodiversity around 4 axes (land, infrastructure, purchasing and processes).
Ecosystem based adaptation (EBA) :
- Voluntary guidelines for the design and effective implementation of ecosystem-based approaches to climate change adaptation and disaster risk reduction (November 2018, COP14 CBD) (CBD)
- 2013 EU Strategy on Green Infrastructure
- EU Research and Innovation agenda on Nature-Based Solutions and Re-Naturing Cities
- site naturalclimate.solutions : focus on biodiversity restoration
- Friends of EBA: informal network of organizations to promote collaboration and knowledge sharing on EbA
- Ecosystem-based solutions (GIZ): more than 120 EbA solutions