water

Natural Water Retention Measures (NWRM) are multi-functional measures that aim to protect and manage water resources and address water-related challenges by restoring or maintaining ecosystems as well as natural features and characteristics of water bodies using natural means and processes. Their main focus is to enhance, as well as preserve, the water retention capacity of aquifers, soil, and ecosystems with a view to improving their status. NWRM have the potential to provide multiple benefits (see benefits table), including the reduction of risk of floods and droughts, water quality improvement, groundwater recharge and habitat improvement. The application of NWRM supports green infrastructure, improves or preserves the quantitative status of surface water and groundwater bodies and can positively affect the chemical and ecological status of water bodies by restoring or enhancing natural functioning of ecosystems and the services they provide (see ecosystem services). The preserved or restored ecosystems can contribute both to climate change adaptation and mitigation.

The channel containing or formerly containing the water of a river. (Source: BJGEO)

Forest harvesting can cause severe disruptions to the hydrologic cycle. Clearcut areas are often subject to localized flooding due to reductions in evapotranspiration caused by removal of trees. Roads and other infrastructure needed to support forest harvesting can also be significant sources of sediment to surface waters. However, negative effects can be minimized when forest harvesting is performed in a water-sensitive manner and measures are taken to maintain the natural hydrological functioning of the landscape.

A biophysical parameter is a measurable characteristic that can help in defining a particular system. It can cover individual substances, groups of substances or be defined by its measurement method like turbidity or the mesurement of oxygen consumption like BOD5 or COD. It is generally expressed by a value and its unit.

EU definition:
Green Infrastructure is addressing the spatial structure of natural and semi-natural areas but also other environmental features which enable citizens to benefit from its multiple services. The underlying principle of Green Infrastructure is that the same area of land can frequently offer multiple benefits if its ecosystems are in a healthy state. Green Infrastructure investments are generally characterized by a high level of return over time, provide job opportunities, and can be a cost-effective alternative or be complementary to 'grey' infrastructure and intensive land use change. It serves the interests of both people and nature.
Clarification points:
From the perspective of Natural Water Retention Measures (NWRM), green infrastructure refers to new methods of managing water, favouring as much as possible the restoration of natural ecosystems or at least of their key functionalities in terms of water management. It consists of land management or engineering measures which use vegetation, soils, and other natural materials to restore the natural water retention capacity of the landscape. Green infrastructure measures use natural and man-made materials to enhance or improve longitudinal and lateral hydrological connectivity and natural hydrologic processes, including infiltration and runoff control but also purification processes. Green infrastructure can exist at a range of spatial scales, ranging from the very local, to the scale of a neighbourhood, a city or a whole region.
Local scale green infrastructure includes green roofs, permeable pavements and downspout disconnections, all of which can contribute to greater natural infiltration, reduced load on wastewater management systems, and limitations of peak runoff.
At the scale of a city or neighbourhood, green infrastructure can support sustainable urban drainage systems that mimic nature by soaking up and storing water or biodiversity promotion with fish ladders.
At a regional scale, green infrastructure can include the mosaic of managed semi-natural and natural areas that provides habitat, flood protection, cleaner air, and cleaner water. Thus land management strategies such as afforestation and retention of natural water retaining features in agricultural areas such as riparian buffers, ponds and wetlands can be considered as Green infrastructures designed to manage flood risks in downstream urban areas.
One key feature of Green infrastructure is its multi-functionality. The underlying principle of green infrastructure is that the same area of land can offer multiple benefits if the natural or man-made ecosystem is in a socio-ecologically sustainable state. Benefits of green infrastructure include a more natural hydrological cycle and ecosystem services related to biodiversity and human amenity. Green Infrastructure investments are generally characterized by a high level of return over time, provide job opportunities, and can be a cost-effective alternative or be complementary to 'grey' infrastructure and intensive land use change. Green infrastructure serves the interests of both people and nature.

The sloping side of any hollow in the ground, especially when bordering a river. (Source: CED)

An enclosed body of water, usually but not necessarily fresh water, from which the sea is excluded. (Source: WHIT)