Logo Leibniz Universität Hannover
Logo Leibniz Universität Hannover
  • Zielgruppen
  • Suche

Study Group: Water Ecology

Supervisors: Prof. Dr. Richard Pott

Object of Study:

The “Water Ecology” study group examines the coexistence of plants and plant societies and their ecological conditions and interactions in the aquatic/amphibian and adjoining terrestrial environment. Plant societies are often the result of long-term effects elicited by biotic and abiotic factors, not seldom associated with anthropogenic impacts. They are therefore the most important bioindicators for environmental conditions and their alterations. Finally, the vegetation, i.e. the sum of all plant societies encountered in one area, constitutes the decisive resource and the most significant structural entity of ecosystems. Vegetation ecology therefore has a key role to play in many issues concerning the occurrence, structural organization and alteration and/or stability of biocenoses composed of microorganisms, plants, animals, and humans, starting from relatively simple observations of single plant populations all the way to very complex studies focusing on whole ecosystems and landscapes in space and time.

In basic ecologic research, the hydrochemical and biocenological studies on the various types of waterbodies in northwestern Germany constitute the main object of our current research work. Taking into consideration the vegetation of the terrestrial surrounding and material imports from the atmosphere, we elaborate models applicable to the complex events of material transport processes mediated by groundwater and precipitation as well as material transformation and accumulation in limnic ecosystems. To this end, a broad spectrum of various methods are available for the sampling and analysis of groundwater, interstitial water, and surface water. Water-ecological research is thus concerned with the important issues of biodiversity on the level of single plant species and the vegetation, and with the physical and chemical environmental parameters.

For further information follow this link

Water Ecology Network:

The study group is composed of:

  • Vegetation ecologists and geo-ecologists (Institute of Geobotany)

  • Microbiologists (Institute of Microbiology)

  • Limnologists (Biology Station “Heiliges Meer” [Holy Sea], external branch of the Westphalian Natural History Museum)

Research Projects:

Interactions between vegetation and the hydrochemical properties of near-surface groundwater in heather and woodland complexes and in agricultural areas used for farming located in the Pleistocene sand landscapes of northwestern Germany.

Various Bachelor’s and Master’s theses:

Apart from the chemical and physical properties of the base rock and soils, vegetation exerts a crucial influence on the quality of near-surface groundwater. As a consequence of interception and the filtration of dusts, but also the species-specific and age-specific leaching of inorganic and organic compounds from leaf surfaces, vegetation effects a modification of the hydrochemical properties already on the level of precipitation water. The differences between the precipitation on open spaces and vegetation-covered spaces, existing under natural conditions, are greatly enhanced by emissions from industry, agriculture, and road traffic. At the beginning of the seepage-water passage, vegetation litter represents an important influential factor for material freights and the pH value of seepage water. In addition, the translocation of various substances carried along with the seepage water is counteracted by the uptake of plant nutrients by the root system. Physical and chemical interactions with the soil matrix, which proceed in the course of the seepage water’s further passage into the ground, finally determine, apart from the influence of the vegetation, the hydrochemical properties of the near-surface groundwater.

In the scope of Bachelor and Master degree projects, exemplary model studies are conducted on the influences of vegetation on the properties of the groundwater in landscapes of northwestern Germany. Using lysimeters and groundwater filters, changes noticeable in the hydrochemical properties during the seepage of precipitation water down to the level of near-surface groundwater are recorded. In addition, the determination of seasonal changes in the hydrochemical properties of precipitation water, seepage water, and groundwater represent an essential aspect of these studies. Complexes of birch and oak woods as well as medieval heather landscapes are available as study areas in the nature preserve “Heiliges Meer” (District of Steinfurt) located in Westphalia. This area has not been subject to any land use for over 80 years, with the exception of heather management, and can be compared with surrounding agricultural land-use spaces and a drinking-water supply area in Emsland (waterworks of Gremsmühlen, Lingener Land water board), whose cultivation of maize and cereals and pasture farming represent the typical forms of land use and management prevalent in this landscape space. As far as the agricultural land-use areas are concerned, the study focus is set on changes in the hydrochemical properties of seepage water and groundwater occurring in the course of the transition from intensive to extensive management. Study objects are spaces which underwent a change from agricultural field management to grassland farming in 2001 and/or in the early 1990s.

Aquatic ecosystems can be influenced to a considerable degree in their chemical mechanisms by upwelling groundwater. Other topics under study consist in elucidating the influence of the terrestrial vegetation in areas surrounding a waterbody, and the effects of material imports from agriculture and road traffic into smaller standing waterbodies, which are embedded in the heather and/or agricultural landscape.