Knowledge gaps

First, there is a need for agreed methods that allow comparison of results and syntheses.[...] there is a need for integrative approaches that assess the multiple benefits derived from a particular contribution from nature to people.

This chapter has indicated that if status and trends in nature’s contributions to people and their impact on quality of life are to be better understood across Europe and Central Asia, four key changes are required in approaches to knowledge generation on these contributions.[...] there is limited empirical evidence on how individual contribution from nature to people can contribute to the different dimensions of quality of life.[...] there is a need for more integrated approaches to the development of knowledge regarding nature’s contributions to people that involve multiple social actors, including indigenous and local knowledge holders

Central Asia cannot be assessed due to a lack of information except for Kazakhstan, which also reports its endangered Ramsar site officially and was visited by a Ramsar mission.

Many sites of the current system of marine protected area and “other effective area-based conservation measures” in the Mediterranean Sea do not have regulations in place to curb existing pressures or enough means to enforce them. Information about management measures and their effectiveness in maintaining or restoring biodiversity is also lacking

There is strong evidence for a moderate overall decline of bird populations in the region […]However, different species groups and regions exhibit different trends, and knowledge gaps exist. Notably, population sizes are unknown for many species, particularly in Eastern Europe and Central Asia (BirdLife International, 2017).

The diversity of terrestrial invertebrates in Europe and Central Asia is unevenly explored, with a substantial lack of knowledge for most taxa, especially for below-ground (soil) fauna.

An important gap in knowledge regarding current as well as future changes is genetic responses to environmental changes[...]Integration of a genetic component is of paramount importance for conservation of genetic resources as well as for modelling of future trends in marine biodiversity

Freshwater systems: The chemical status of 40% of Europe’s surface waters remains unknown (EEA, 2015d), considering that good chemical status was only achieved for all surface bodies in five of the 27 European Union member States, it is likely that the environmental conditions of some of these water bodies are poor.

It was often impossible to quantify the relative role of drivers of change in determining trends in species and ecosystems. This was due to lack of synthetic studies on this subject and the limited ability to meta-analyze the literature to provide this evidence

Low capacity or difficult access means that regions such as Caucasus, the Arctic part of Europe, Romania, Croatia, the Faroe Islands and the Azores are underrepresented in bird conservation status assessments

More substantial knowledge gaps exist for other terrestrial vertebrate groups

Open ocean plankton communities are also poorly known

Overall information on biodiversity trends in agricultural areas decreases from west to east.[...] Capacity building for monitoring biodiversity in agricultural areas in the eastern part of the region is thus needed

Promoting a stronger focus on functional diversity in future studies and monitoring schemes may be the best way.

Relationship between biodiversity and ecosystem function and services: For some ecosystem services, there is insufficient data to evaluate the relationship between biodiversity and ecosystem service provision

Similarly, almost a quarter of all European freshwater molluscs are data deficient and many might prove to be threatened once enough data become available to evaluate their extinction risk

The most notable knowledge gap in marine biodiversity for Europe and Central Asia is the lack of data on status and trends of biodiversity in deep-sea areas (>200 m) despite canyons, seamounts and other important deep-sea habitats and ecosystems being present in Europe and Central Asia Seas and Oceans

The small amount of data available on taxa more difficult to observe and distinguish, such as Syrphids and other Diptera, suggest high levels of diversity and numerous rare and threatened species (Kelcey, 2015). Thus, more surveying of such taxa would generate valuable new knowledge on urban biodiversity.

There are at least 100,000 species of insects known in Europe, and an unknown number of earthworms, arachnids, snails and other invertebrate species. However, it is plausible that several hundreds of thousands of species of invertebrates occur in Europe and Central Asia. Despite this extremely high diversity, and importance for ecosystem services, only a very small proportion is listed in the IUCN Red List

There are no meaningful trends in geographic extent or population size of freshwater species available for Europe and Central Asia

There were very few studies investigating the impact of land-use change and even fewer investigating future projected impacts of pollution, invasive species, fishing and other drivers of change

This underestimation of marine diversity implies that the trends are incomplete for most marine taxa [...]it is estimated that between one-third and two-thirds of marine species are still to be described."
-"Biases across taxonomic groups in marine systems are also largely documented (McCauley et al., 2015; Poloczanska et al., 2013)"
-"Although there has been an exponential increase in research on marine archaea, bacteria and viruses, and evidence that archaea and viruses may increase in importance with depth (Danovaro et al., 2015) their biodiversity and functioning is still largely unknown."
-"Less than 10% of all species of vascular plants known to occur in the region have been assessed by the IUCN Red List (2,483 species for an estimated >30,000 for the region) (IUCN, 2017c)."
-"We were unable to assess status and trends in diversity, biomass and community composition of soil and freshwater micro-organisms: Protozoa, Bacteria, Rotifera, Nematoda, Tardigrada,"

To better understand and predict biodiversity trends in agricultural areas in Europe and Central Asia, it will be necessary: (i) to reinforce the knowledge basis on the demography and population dynamics of species (including the role of behaviour, density-dependent effects, and extinction debt); (ii) to account for small-scale spatio-temporal effects and scale up biodiversity changes and trends from local to national and regional levels; and (iii) to detail the effects of changes in agricultural practices (characteristics of the varieties grown, harvesting techniques, types of pesticides used, etc.) to a greater extent (Kleijn et al., 2011).

we found large gaps in knowledge on habitat extent and intactness, and species conservation status and trends for Eastern Europe and Central Asia. For instance, there is no systematic monitoring of plant and animal species across the range of these subregions [...]the European Union long-term monitoring data is available almost exclusively for protected areas, which poses the risk of underestimating overall biodiversity trends in these regions.

Biases across taxonomic groups in marine systems are also largely documented (McCauley et al., 2015; Poloczanska et al., 2013)

Although there has been an exponential increase in research on marine archaea, bacteria and viruses, and evidence that archaea and viruses may increase in importance with depth (Danovaro et al., 2015) their biodiversity and functioning is still largely unknown.

Less than 10% of all species of vascular plants known to occur in the region have been assessed by the IUCN Red List (2,483 species for an estimated >30,000 for the region) (IUCN, 2017c).

We were unable to assess status and trends in diversity, biomass and community composition of soil and freshwater micro-organisms: Protozoa, Bacteria, Rotifera, Nematoda, Tardigrada,

Climate change is also expected to further increase the stress on freshwater ecosystems, not only by changing species distribution but also by exacerbating the symptoms of eutrophication due to loss of planktivorous species through warming and salinization (inconclusive).

A broader knowledge basis on trends in habitat extent, intactness and species conservation status was available for Western and most of Central Europe than for Eastern Europe, Central Asia and Balkan countries in Central Europe (3.4, 3.6).[...] most terrestrial and freshwater ecosystems in Eastern Europe and Central Asia

Due to lack of quantitative knowledge the relative role of drivers of change in determining trends in extent and intactness of habitats and in species diversity and abundance could only be attributed in terms of a coarse classification. Moreover, information is lacking on the interacting effects of several drivers on biodiversity (well established)

Major gaps on status and trends of taxonomic groups concerned invertebrates, most marine and freshwater species, bryophytes, lichens, fungi and microorganisms - executive summary. Only a minor fraction of the deep-sea floor and of known seamounts have been subject to biological investigation (well established) (3.3., 3.4, 3.6 Indigenous and local knowledge on biodiversity trends was only partially available.

These knowledge gaps greatly reduce the ability to monitor progress towards international biodiversity targets and to inform policy to avert further biodiversity loss. For example, current instruments such as the European Union Habitats Directive and Natura 2000 programme do not consider algae, fungi or lichens, and only a small fraction of invertebrates

Knowledge gaps remain with respect to changes in physiological processes and evolutionary adaptations to new climatic conditions

Confidence is generally high in all statements, yet often somewhat decreasing towards Eastern Europe and Central Asia, usually due to a lack of accessible literature and insufficient number of studies analysing trends and impacts.

There were very few scenario studies which modelled feedbacks from direct drivers, such as climate change or land use change, to socio-economic trends (an integral component of the IPBES conceptual framework; Diaz et al., 2015), highlighting a key gap in the scientific literature

They also indicate that most studies addressed the different dimensions of value only independently (e.g. MEA, 2005) or linked nature with a limited set of mainly instrumental values, excluding other dimensions such as intrinsic or relational values.

All reviews reveal knowledge and information gaps for Central Asia and, to a lesser extent, for Eastern Europe

Studies covering the marine realm were poorly represented, and almost absent from visions and pathways.

Studies which explicitly covered indigenous and local knowledge were largely unrepresented in all the reviews.

The analysis of how values were included in the exploratory scenario and normative scenario (or pathways) literature showed that some dimensions of value (i.e. intrinsic values) were not considered by the majority of futures studies [...]recognizing the diversity of values [...]socio-cultural approaches to valuation

The coverage of nature’s non-material contributions to people, and quality of life indicators was poor in most scenario and modelling studies and they were absent from, or limited to, recreational benefits in most visions and pathways studies

The direct drivers of pollution and invasive alien species also had limited coverage in exploratory scenarios compared to other direct drivers, such as climate change and land use change

The pathways review found that there are very few fully developed pathways studies that go beyond narrative presentations of pathways and are supported by quantitative modelling

The review of integrated models revealed that integrated studies which attempt to capture some of the complex interdependencies between human and environmental systems under multiple drivers of change are rare, particularly for Eastern Europe and Central Asia

The visions literature search yielded only a limited number of regional visions, with a small number of visions from the scientific literature

Very few studies were available for Central Asia and to a lesser extent for Eastern Europe (well established)

Less information was also available for marine systems than for terrestrial and freshwater systems (well established)

No studies were found that assessed future flows of nature’s contributions to people across countries, which would have been important to assess the impacts of the scenarios and pathways for Europe and Central Asia on other parts of the world (well established)

There is also a significant gap in the current literature in recognizing the diversity of values, with the focus being mainly on instrumental values (well established)