-
-
F.C.J.M. Roozen,
E.T.H.M. Peeters,
R.M.M. Roijackers, Wyngaert,
I.J.J,
van den,
H. Wolters,
Coninck,
H.C,
B.W. Ibelings,
A.D. Buijse,
M. Scheffer
[show abstract]
[hide abstract]
ABSTRACT: Key variables in ecosystems tend to operate on widely different time-scales. These time-scales become relevant when a disturbance rocks the ecosystem. Here we try to explain the fast dynamics of plankton and nutrients in the water column of floodplain lakes after disturbances (inundations). We take advantage of natural experiments, that is occasional massive overflow of floodplain lakes with river water. We sampled 10 lakes in two floodplains along the Dutch river Waal monthly for 3 years, capturing the impact of three inundation events. The inundations reset the plankton as well as chemical composition of most lakes to largely the same state. While biologically inert macro-ion data reflected a large and long lasting impact of the river water, dynamics of nutrients, phytoplankton and zooplankton communities between lakes diverged in a few weeks to regimes characteristic for the different lakes. While one spring inundation synchronized plankton dynamics to let the subsequent clear water phase occur at the same moment in different lakes, winter inundations did not have the same effect and apparently dynamics quickly diverged. Our results showed that effects of inundations and other processes that affect the state of the ecosystem should be studied considering the level of the slow components such as the sediment nutrient pool, fish stock and macrophyte communities. Plankton communities and lake water nutrient status give a practically instantaneous reflection of the condition of these slow components
River Research and Applications 24 (2008) 4.
-
Forestry and Climate Change.
-
-
-
-
-
[show abstract]
[hide abstract]
ABSTRACT: The aim of this study was to assess the sustainability of carbon sinks in managed or unmanaged forests in Europe and Amazonia. First, the functioning and seasonal variability of the carbon sink strength in forest ecosystems was analysed in relation toclimate variability. To this end, existing global data sets of ecosystem fluxes measured by eddy correlation were analysed. A simple, comprehensive empirical model was derived to represent these flux variabilities. Furthermore, new soil respiration measurements were initiated in the Netherlands and Amazonia and their usefulness to understand the uptake and emission components of carbon exchange was analysed. Then, two long-term forest dynamics models were parameterized (FORSPACE and CENTURY) for Dutch Pinus and Fagus forests, to study the development of forest carbon stocks over a century under different management and climate scenarios. Finally, using the empirical model as well as the long-term models, scenario predictions were made. It turns out that uptake rates are expected to decrease in a climate with higher temperatures, but that storage capacity for carbon can be expected to be slightly enhanced, especially if also the management intensity is carefully tuned down.
-
K. Kramer,
B.S.J. Nijhof,
S.J. Vreugdenhil,
Werf,
D.C, Wyngaert,
I.J.J,
van den,
J. Armbruster,
V. Späth,
D. Siepmann-Schinker
-
G.J. Nabuurs, Wyngaert,
I.J.J,
van den,
W.D. Daamen,
A.T.F. Helmink,
Groot,
W.J.M,
W.C. Knol,
H. Kramer,
P.J. Kuikman
[show abstract]
[hide abstract]
ABSTRACT: The Netherlands as being a Party to the United Nations Framework Convention on Climate Change (UNFCCC) has the obligation to design and operationalise a national system for the Land Use, Land-Use Change and Forestry sector (LULUCF). This report presents such a semi dynamic system at Tier 2 for forests and other nature terrains (trees outside forests, heathland, peats, and sandy areas) in The Netherlands. With this system a full account for carbondioxide and other greenhouse gas balance is presented and recalculated for 1990 ¿ 2002
-
Effects of silvicultural regimes on dynamics of genetic and ecological diversity of European beech forests; impact assessment and recommendations for sustainable forestry.
-
K. Kramer,
B. Degen,
T. Hickler,
W. Thuiller,
M.T. Sykes,
Winter,
W.P, Wyngaert,
I.J.J,
van den,
Werf
-
