**5. Role of glacial biodiversity in the glacial-ecosystem functioning and services**

Given the global change scenarios, it is opportune to analyze the role of glaciated areas in the context of persistent change from the physiographic point of view as well as the glacial biodiversity they host.

Standardized long-term monitoring, additional high-quality empirical studies on key organisms and landforms, and further development of analytical methods are of extreme importance in helping to quantify the extinction debt better and to more successfully enhance and protect glacial biodiversity.

Glacier shrinkage will alter hydrological regimes, sediment transport, and biogeochemical and contaminant fluxes from rivers to oceans, which will profoundly influence the natural environment and the ecosystem services that glacier-fed rivers provide to humans, particularly provision of water for agriculture, hydropower and consumption [4]. Biodiversity influences ecosystem functioning through changes in the amount of resource use or water self-depuration processes (regulating services) but is also a source of scientific and tourist attraction (cultural service).

Glacial biodiversity has an intrinsic value; most of the species are highly specialized to live in harsh environments, thus highly vulnerable to changes also of low intensity, have low dispersal ability and in most of the glacialized area of the world are endemic. Therefore, glaciated areas become territories with a collection of communities and species that mostly differ from those dominant in middle and low altitudes as well as differ between geographic areas. In addition, insects and other arthropods (e.g., spiders) living on the moraines, on the glaciers or flying on the glaciers (e.g., chironomids and stoneflies) act as additional source of food for some high-altitude mammals and bird species living at the edge of ice-related landforms [81, 82]. Therefore, glacial biodiversity is able to furnish an additional important naturalistic value of glacialized mountain regions.

Aquatic and terrestrial insects living in glacialized areas are trophically connected [83, 84], but not all insect groups react in the same way to the ongoing

**157**

*Glacial Biodiversity: Lessons from Ground-dwelling and Aquatic Insects*

glacier retreat. Increasing glacial retreat differently affects ground-dwelling and aquatic insect taxa: ground beetles respond faster to glacier retreat than do nonbiting midges, at least in species richness and species turnover patterns [84]. It depends on how fast habitat conditions change in relation to glacier retreat: the terrestrial environment changes faster than the aquatic environment. For instance, an increase of 0.6°C in summer temperatures approximately doubled the speed of colonization of the recently deglaciated terrains by ground-dwelling invertebrates [39]. The glacial stream lengthens but the physicochemical features and hydrological regime may not change for a long time, until the surface of the glacier is reduced to a few hectares and finally the environment becomes less extreme for life. As a result, as long as the environmental conditions remain extreme, the community in

Because even small ecosystem fragments like glaciers or other ice-related landforms have conservation value for insect biodiversity and ecosystem services, a better understanding and delineation of the species that need to be protected is also important. Funding of long-term research activities on habitat conservation in general, and specifically on insect science and taxonomy, is especially important to evaluate and mitigate future changes in insect communities, obtain reliable insect

A recent large-scale study aimed to investigate trends in insect abundances over space and time has brought evidences about an average decline of terrestrial insect abundance (ca. 9%) per decade and an increase of freshwater insect abundance (ca. 11%) per decade. Both patterns were particularly strong in North America and some European regions [85], and the hypothesized drivers are land-use change and

Ground beetles and non-biting midges are among the animals best adapted to live at high altitudes, specifically to colonize the glaciers and surrounding terrestrial and aquatic habitats. They are present with few species adapted to low temperatures

Spatio-temporal shift in insect communities in relation to the ongoing climate change is one of the most common patterns in mountain regions, but it is important to highlight that it will not affect all species equally [85, 86]. Aquatic and terrestrial insect communities seem to be differently affected by climate change. Firstly, because temperature variability is stronger on the ground with respect to water, aquatic insects are required to make smaller behavioral or physiological adjustments than terrestrial insects and aquatic habitats will be more buffered from climate warming [86]. In addition, terrestrial insects may have wider opportunities to survive in appropriate microclimate colonizing or surviving in ice-related microhabitat, thanks to the higher microhabitat heterogeneity on the ground with respect

The chapter provides a synthesis about the fascinating adaptations in morphol-

Three research goals should be addressed in the near future: (i) increase the studies aimed at describing the glacial biodiversity; (ii) plan long-term monitoring

ogy, behavior and physiology in terrestrial and aquatic species, on the species distribution in relation to the ice-related landform heterogeneity and on which species are threatened with extinction due to climate change and pollution. The future challenge will be to try to improve the knowledge of the glacial biodiversity in high-altitude and high-latitude areas notwithstanding the difficulty of accessing

and food scarcity, factors that make these habitats extreme for life.

*DOI: http://dx.doi.org/10.5772/intechopen.92826*

the glacier-fed stream is not affected.

**6. Conclusions**

climate change.

to the aquatic habitat.

most of these areas.

time series and discover species before they go extinct.

#### *Glacial Biodiversity: Lessons from Ground-dwelling and Aquatic Insects DOI: http://dx.doi.org/10.5772/intechopen.92826*

glacier retreat. Increasing glacial retreat differently affects ground-dwelling and aquatic insect taxa: ground beetles respond faster to glacier retreat than do nonbiting midges, at least in species richness and species turnover patterns [84]. It depends on how fast habitat conditions change in relation to glacier retreat: the terrestrial environment changes faster than the aquatic environment. For instance, an increase of 0.6°C in summer temperatures approximately doubled the speed of colonization of the recently deglaciated terrains by ground-dwelling invertebrates [39]. The glacial stream lengthens but the physicochemical features and hydrological regime may not change for a long time, until the surface of the glacier is reduced to a few hectares and finally the environment becomes less extreme for life. As a result, as long as the environmental conditions remain extreme, the community in the glacier-fed stream is not affected.

Because even small ecosystem fragments like glaciers or other ice-related landforms have conservation value for insect biodiversity and ecosystem services, a better understanding and delineation of the species that need to be protected is also important. Funding of long-term research activities on habitat conservation in general, and specifically on insect science and taxonomy, is especially important to evaluate and mitigate future changes in insect communities, obtain reliable insect time series and discover species before they go extinct.
