Present state and future prospects for groundwater ecosystems

Abstract

Ecological and socioeconomic aspects of subterranean hydrosystems have changed during the past 40–50 years. The major environmental pressures (mainly anthropogenic ones) impact the quantity and quality of groundwater resources and the state of subsurface ecosystems, and it is expected that the environmental pressures on groundwater will continue, at least until 2025, unless new environmental policies change this state of affairs. The world demographic increase and the general rise of water demand constitute one of the major environmental pressures on groundwater ecosystems especially in less developed countries in Africa, Asia and South America. Specific human activities leading to the depletion of groundwater reserves include agricultural practices, landscape alteration, urbanization demand for domestic and public drinking water, various industrial activities such as thermoelectric production and mining, and the rise of tourism in coastal areas. Climate change is contributing to the water crisis too, especially in areas with arid climate and/or in some humid monsoonal countries. The overload of aquifers with pollutants derived from agriculture (fertilizers and pesticides), from industry (release of hydrocarbon chemicals, especially spills), from waste and industrial waters, from domestic and industrial landfills, from the infiltration of pollutants from surface and from the intrusion of saline water affect groundwater quality. The dangerous increase in contaminated subsurface sites with chemicals and microbial pathogens brings with it health risks to humans. Changes of redox condition in groundwater zones, changes of biological diversity, vegetation changes with modification of agriculture practices and impacts at the biosphere scale, such as the increase in the concentration of nitrous oxides in the atmosphere, all impact groundwater ecosystems. Groundwater ecosystems must be better investigated and understood. Economic, social and ecological lines of thinking have to be combined in order to achieve meaningful policies for the sustainable development of groundwater reserves and for the protection of subsurface ecosystems. Practical measures and ideas for the development of policies up to the 2025 time-horizon should improve the sustainable usage of the world's groundwater resources.

Biodiversity, functional roles and ecosystem services of groundwater invertebrates

“…biogeochemical water purification, Herman et al 2001;Danielopol et al 2003Danielopol et al , 2004 although there is a strong growing interest in dependency on groundwater by other ecosystems (e.g. Clifton and Evans 2001;Boulton and Hancock 2006;Bergkamp and Cross 2006).…”

“…Clifton and Evans 2001;Boulton and Hancock 2006;Bergkamp and Cross 2006). Aquifers and their inhabitants are the perfect example of a completely groundwater dependent ecosystem (Humphreys 2006) yet our understanding of how groundwater invertebrates influence ecosystem services in aquifers is almost nonexistent (Danielopol et al 2003). Taxonomists and ecologists are now appreciating the unexpectedly-diverse assemblages of groundwater invertebrates (stygofauna) in aquifers across the world (Marmonier et al 1993;Danielopol et al 2000;Humphreys 2006), raising the key question: what is the relationship between this biodiversity and groundwater ecosystem services provided or facilitated by stygofauna?…”

Review: Microbial biocenoses in pristine aquifers and an assessment of investigative methods

“…Today, they are recognised to share complex biological interactions and to impact a wide range of biogeochemical processes. Aquifers are thus more and more considered as ecosystems with specifically adapted biocenoses (Danielopol et al 2003;Hancock et al 2005;Marmonier et al 1993;Preuss and Schminke 2004).…”

Groundwater dependent ecosystems. Part II. Ecosystem services and management in Europe under risk of climate change and land use intensification

“…An ecological understanding of the value of GDEs must be complemented with an awareness of the economic and social impacts of groundwater modification. This can be achieved through a multidisciplinary approach which links environmental, economic and social assessment (Danielopol et al, 2003). 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 13 Ordinary resource users may be unable to identify ecosystem functions directly, but rather recognise them through the goods and services they produce and can be assessed in economic, ecological and socio-cultural terms.…”