Sessions details
1:. Introduction: Water-soil-vegetation relationships
in the natural Biebrza wetlands
1.1 Wetlands in the
hydrological systems
Tomasz
Okruszko
Wetlands may be able to play different roles in the
landscape depending on the source of water; hydrological
feeding of wetlands may be rain fed (ombrogenic),
groundwater fed (topogenic and soligenic) or river fed
(fluviogenic).
Ombrogenic - Wetlands with a difficult outflow and where
there is a low level of evapo-transpiration tend to be
rainfed or ombrogenic. The catchment tends to be very
small and in extreme conditions, such as dome peatlands
there is no catchment and the only water source is
rainfall. These wetlands are typically found in mountains
or close to the sea.
Soligenic - Wetlands with a of soligenic type of
delivery tend to occur near the edge of larger valleys on
local groundwater outcrop or small localised peatlands on
the slopes of moraine hills. The most common areas
occupied by soligenic wetlands are the upper parts of the
river basin when they occupy a cross-section of the
valley and the river that drains them.
Topogenic - Wetlands with topogenic type of delivery
occur watershed areas or on the bottom of wide basins. A
characteristic feature of such wetlands is strong
hydration with little mobility in the ground water, which
in Summer cannot always make up for the water
evaporation.
Fluviogenic - River fed wetlands could be compared to
retention reservoirs where there is typically a flood
reserve. Such wetlands occur where water reserves are
created by a suitably big catchment area. Rainfall or
thaw freshets that occur in river basin run to the bottom
of the valley causing heavy irrigation or flooding in the
area for limited period. Regular occurrence and long
duration of the inundation are basic factors of
fluviogenic delivery.
Being aware of the hydrological type of delivery forms
the first step for understanding the chemical and
biological functional requirements of wetlands
ecosystems. Lecture aims on introduction of the wetlands
function in the catchment depending on their hydrological
type.
1.2 Water-related
physical attributes of organic soils of natural
wetlands
Jan
Szatyłowicz
• the organic soil solid phase characterisation
(botanical composition, degree of decomposition and ash
content),
• basic physical properties (particle and bulk density,
porosity),
• soil water characteristic of peat soils (factor
influencing on the characteristic),
• saturated and unsaturated hydraulic conductivity of
organic soil,
• water storage in peat soil profiles and soil volume
changes,
• peat accumulation,
• organic soil classification.
1.3 Wetland vegetation
- background concepts (influence of habitat and
management, natural vs. seminatural wetlands, zonation,
structure of phytosociological and ecological
classifications)
Wiktor
Kotowski
We will introduce principles of vegetation science and
review major concepts related to wetland vegetation
classification and background of observed vegetation
patterns. The relation between vegetation typologies and
wetland types will be addressed, with special reference
to riparian habitats. We will also explain methodological
approach to vegetation studies, analysing examples of
descriptive surveys, analyses of vegetation-habitat
relationships and experimental studies on community
mechanisms.
1.4 Characterisation
of major vegetation types in undrained wetland habitats
(examples from the Biebrza Valley), understanding natural
zonation
Wiktor
Kotowski
Major vegetation types typical for undrained wetland
will be described, including: tall helophytes, tall sedge
communities, sedge-moss fens, bogs, alder forests, bog
forests. Focusing on natural riverine wetlands, we will
discuss concepts explaining vegetation zonation patterns
in terms of abiotic conditions and biotic interspecific
interactions.
2:. Hydrology and soil properties of organic wetlands:
Biebrza as an example of relationships in wetlands -
transition from natural to transformed
2.1 Hydrology of the
Biebrza Upper Basin
Okke Batelaan
• An identification of the key hydrological processes
occurring in the Biebrza Upper Basin; The processes are
described as a result of the geographical,
hydrogeological and meteorological conditions of the
catchment. The more anthropogenic influences of the
hydrology are treated in later lectures.
• A description will be given of the current state of
the hydrological knowledge of the hydrology of the Upper
Basin by way of a short overview of analyses of
hydrological data. This description includes an analysis
of the hydrometeorology, surface water and groundwater
system.
• A presentation of the results of groundwater modelling
and distributed catchment runoff modeling in dependence
of topography, soil, land-use and meteorology.
• A presentation of local groundwater-surface water
interaction measurements and modelling at a headwater
section of the Upper Biebrza River.
• A zooming in to some transects along which detailed
time series of groundwater levels have been observed and
are complemented by vegetation and nutrient cycling
mapping.
2.2 Flooding and
Inundation in the Lower Biebrza Basin
Jarosław
Chormański
• Importance of flooding in wetlands
• Surface water hydrology of the Biebrza Lower
Basin
• Flood and inundation: different water types
• Floods observation: water level dynamics
• Flood and Inundation mapping in wetland area
(measurements, Remote Sensing, GIS-based hydraulic
modeling)
• Relation between flood extent, inundation and
vegetation zones in Lower Biebrza Basin.
2.3 Water-related
physical attributes of organic soils of transformed
wetlands
Jan
Szatyłowicz
• characteristic of moorsh formation process,
• influence of moorshing process on water storage and
water transmission in soil,
• peat shrinkage and hydrofobicity,
• soil subsidence,
• capillary rise in soils.
2.4 Water quality
aspects in the hydrology of wetlands
Marek
Gielczewski / Ignacy Kardel
• A presentation of patterns and changes in groundwater
quality in dependence to different soil (peat and mursh)
types dominating in the Biebrza valley
• An analysis of the seasonal and annual trends in
groundwater quality in the Biebrza valley
• A presentation of patterns and changes in surface
water quality in dependence to different soil (peat and
mursh) types dominating in the Biebrza valley
• An analysis of the seasonal and annual trends in
surface water quality in the Biebrza river
3:. Management and restoration of wetlands differing in
the degree of human disturbance
Part 1
3.1 Spontaneous
secondary succession in drained and not managed wetlands
- information from spatial analyses, rate of changes in
time and management solutions
Hubert
Piorkowski
Most of open wetlands in temperate zone used to exist in
semi-natural conditions under mowing or grazing
management. Cessation of this landuse is followed by fast
successional changes of vegetation. The rate of changes
in time and their spatial extent in the Biebrza Valley
will be demonstrated by means of remote sensing and
spatial analyses. Management solutions and usefulness of
management support systems will be discussed.
3.2 The impact of land
use changes and management on the trophic status and
biodiversity of wetlands
Martin Wassen
Land use is one of the factors most directly
influencing biodiversity (ecosystems, species and
genotypes of plants, animals and micro-organisms).
Large part of the Earth surface is under production.
The intensity of current production methods and the
impacts on the physical-chemical conditions of the soil
(water and nutrient status) are important driving
forces of the decrease of biodiversity. Furthermore,
land use also affects the remaining nature areas,
through environmental impacts such as desiccation,
acidification, eutrophication and fragmentation.
Knowledge of key-processes vital for ecosystem
functioning is therefore required in order to be able
to improve ecosystem quality as a condition to
biodiversity conservation.
Ratification of the Convention of Biodiversity by many
countries implies that loss of biodiversity should be
prevented and counteracted. Important means are the
protection of nature areas, e.g. through survival
strategies for forest and other types of nature, and
the restoration of lost nature, e.g. by taking
agricultural land out of production, reversing
eutrophication processes and rewetting wetlands. For
understanding eutrophication, i.e. the process of
nutrient enrichment of ecosystems we primarily need to
know which nutrient(s) is limiting primary
productivity. Next, quantification of pools and fluxes
of limiting nutrients is required. The effect of
potential increases of nutrient availabilities can then
be predicted by analyzing the various nutrient fluxes
operating in these ecosystems. In wetlands these fluxes
include atmospheric deposition, nutrient supply by
flooding and groundwater flow, nutrient leaching to
groundwater and for nitrogen fixation and
denitrification. Also grazing or harvesting natural
products in the form of hay production should bee
considered. Increased availabilities may also result
from changes in soil nutrient turnover rates due to
altered ecosystem properties such as changes in
hydrological dynamics and acidification. Management
often strives for decreasing productivity and
preventing ecosystem succession towards higher
productive ecosystems.
We quantified (annual) nutrient flows along
productivity gradients in floodplains, fens and
meadows. We also identified key processes for ecosystem
functioning and related them to landscape features on
one hand and vegetation structure, plant species
composition and plant diversity on the other hand.
Results will be discussed in relation to the type of
nutrient limitation, plant diversity - productivity
patterns and management.
3.3 Ecohydrological
investigations of Flemish river valleys. Basis for
development of ecosystem visions
Okke Batelaan /
Patrick Meire
In the last 10 years many ecohydrological studies have
been performed in Flemish river valleys. Several of them
were executed in the framework of developing an ecosystem
vision for mostly valuable floodplain areas. Ecosystem
visions have been defined in these studies as: A tool for
nature policy with as purpose the optimalisation of the
quality and structure of ecosystems in a certain area. By
designing an ecosystem vision the administrations hope to
gain an insight into the potentials of valley areas. With
potential is meant the possibilities for nature
development and restoration, while taking into account
irreversible abiotic conditions, management and land
organization. Ecosystem visions result therefore in the
spatial mapping of potentials, up to parcel level, and
give orientation to the determining factors and
processes, thereby identifying resulting
bottlenecks.
In this lecture the methodology of the ecosystem visions
is described, including the ecohydrological field and
desktop studies, such as vegetation mappings,
hydrological system modeling, eco-hydrological system
analyses and scenario testing. Examples of
ecohydrological investigations in different valleys are
given, which indicate that vegetation types in specific
areas are determined by a complex set of biotic and
abiotic conditions. It is shown that the ecohydrological
relationships are process scale and spatially
dependent.
3.4 Water management,
nature conservation and restoration attempts in Dutch
lowland polder areas
Martin Wassen
In the Netherlands reclamation of wetlands has a long
history. The famous Dutch struggle against the water by
building dams and pumping out water has turned many lakes
and marshes and even parts of the sea into land.
Nowadays, the struggle against water has turned into a
struggle for water in areas where agriculture, drinking
water companies and wetland nature reserves compete for
fresh and unpolluted water. This lecture gives an
overview of Dutch water management practices and
addresses current issues in water management for nature
conservation in relation to other water users. Examples
of restoration attempts will be given aiming at reducing
the unwanted effects of drainage, acidification and
eutrophication and re-establishment of plant
species.
Part 2
3.5 Characterisation
of major vegetation types in drained wetland habitats
(examples from the Biebrza Valley), changes in vegetation
patterns after drainage, role of management in suboptimal
hydrological conditions
Wiktor
Kotowski
Typical vegetation types of moderately drained wetlands
are various types of wet meadows - eutrophic hay meadows,
mesotrophic litter meadow, tall herb communities. In more
intensively drained sites, biodiversity declines and
species-poor grassland communities establish. Drainage
can also enhance succession process. On this background
we will discuss the ecological role of vegetation
management in riparian landscapes.
3.6 Water management and nature restoration in
the Schelde estuary: an example of conservation in multi
stakeholder settings
Patrick Meire
• a short introduction on the wetlands in the Schelde
basin with special emphasis on the Schelde estuary
• a description of the major factors leading to the
deterioration of the wetlands, especially the tidal
marshes and how this has lead to major problems
concerning water quality, water quantity and
biodiversity
• a short description of the present management plans
dealing with safety, shipping, water quality and
nature
• presentation of a new integrated approach for the
management of the estuary and the basin with emphasis on
the role of wetlands in this.
3.7 Wetlands as water
users in Integrated River Basin Management
Plans
Tomasz
Okruszko
Integrated River Basin Management (IRBM) should focus not
only on water supply for the different type of water
users, such as agriculture, industry or household, but
also on maintaining water dependent ecosystems. To do
this, some fundamental issues need to be determined such
as whether the wetlands are a) the water user; b) part of
water resources or; c) the structure for modifying water
quantity and quality in the catchment.
In most cases where there are competing water users, the
water distribution decisions are based on a comparison of
how significant the losses will be for each water user if
his water needs are not met.
As a general rule the water boards or other water
management bodies try to balance surface and ground water
resources with the water needs of the particular water
users. Surface water balance models or regional
groundwater models are generally used for establishing
catchment scale water management plans and determining
water policies. Water management plans are identified by
comparison of model results in terms of decision criteria
for particular alternative of water management (often
called a scenario). Each alternative contains a
combination of the system parameters, such as the volume
of the projected reservoirs; decision rule parameters,
area of irrigation schemes and a hierarchy of the water
users.
Typically basins that are used for human purposes
undergo considerable intensification, particularly of
biogenic substances as the sustainability of the wetland
ecosystems is not factored into the water management
plans. In order to perform necessary calculations, where
wetland ecosystem function is also considered, the water
demand of different type of wet habitats also has to be
included in the decision process. Hydrological
characteristics of particular ecosystems could be
employed for this purpose. Their type of hydrological
feeding describes, in general, the sources of water, the
yearly water hydrograph describes the water needs and
specific hydrological parameters (flooding frequency,
maximum depth of groundwater, average waterlogging
period) might be used as decision criteria. An additional
approach may be to model the response of the particular
wetland ecosystem to water deficit in terms of
productivity and/or vegetation composition.
These approaches will not solve all the problems of
which water user is more important and how to set a
hierarchy of water users in the river basin. However it
is a complex issues with ecological, sociological and
economical considerations and the proposed approach at
least creates an understandable method for communicating
with decision makers about wetlands, how much water is
needed and the moment when water deficit in wetlands
occurs IRBM plans should recognise the presence of
wetlands in the catchment. On one hand there are
important functions, which wetlands can perform as a
service provider, for example as a sink of biogens or for
water retention. On the other hand wetlands are water
users just like all other dependants on water from the
river basin.