Retention

Retention - the ability to gather water resources and store them for a longer period of time in biotic and abiotic environment. In a forest there is, among others, retention of flora, soil and ground retention, snow retention, depression retention, water body and flow retention.

A little water retention is the ability to gather water in small natural and artificial water bodies as well as water lifted in channels of small rivers and streams, canals and ditches.

The aims of the little water retention include:

• The improvement of moistness of habitats by lifting ground water on the territories adjacent to the body of water or the water lifting device;
• Changing fast (highly unfavourable) outflow of ground water from forest areas into slowed down ground outflow;
• Enriching and adding variety to the forest environment (diversity, among other things);
• Water accessible to animals, birds, insects and other fauna;
• Water for protection against fire;
• Water for farm purposes, e.g. sprinklers near nurseries;
• The improvement of conditions for recreation and leisure.

In the middle of the 1980s a long period of hydrological drought began which lasted until 1993. As a result, the level of ground water fell significantly. Since 1994 the amount of precipitation has risen; however, hydrological conditions have not improved. Forests pay a high price for it which manifests itself in the increase in the number of fires, the decrease in crops and probably extinction of some species, e.g. ash.

Larger areas of peat bogs, marshes, small ponds, old river beds etc. have survived only in forests. Those which were placed on farmlands have already been dried and changed into arable lands or meadows and pastures. Riparian forests have suffered a similar fate.