Prentice, IC, MT Sykes, W Cramer. 1993. A simulation model for the transient effects of climate change on forest landscapes. Ecological Modelling: 65: 51-70.
Fores are likely to show effects with the changing climate. Many early climate scientists took an optimistic view that the increase in atmospheric carbon would be taken up by trees. Recent evidence shows that this is not the case and that atmospheric carbon levels are increasing. This has lead to two conclusions. Either more carbon is being put into the atmosphere than plants, or in this case trees, can take up, or plants are not capable of using the extra carbon as biomass. This is flawed in some ways as it doesn’t take into account the increased growing season from the increased temperatures. In this article, the researchers use a forest succession model to simulate the effects of climate change on forests and forest succession.
The researchers used the forest succession model with a resolution of 0.1 ha. This simulated a patch interaction through lightand nutrient competition. This made the forest a collection of patches. The model looked at the effects of summer and winter temperature limitations, accumulation of annual foliage net assimilation and sapwood respiration as functions of temperature, CO2 fertilization, and growing-season drought. This means that as the temperature increases, summer and winter temperatures will change but also provide a limiting factor on tree growth. Studies have indicated that as temperature increases, photosythesis rates will increase to a point. At around 80 F, the rate of photosythesis asymptotes and decreases for many temperate hardwood trees. This same curve is also seen for arctic plants with the curve shifted to the left. Trees cannot photosythesis at low temperatures as they need access to available water. Net assimilation and sapwood respiration are limited by temperature for the same reasons. Increase the temperature may not increase the assimilation of carbon but increasing the growing season would. Increasing temperatures can evaporate the soil moisture limiting available water for photosynthesis.
Structure, composition, and biomass in boreal and temperate deciduous forests approched equilibrium values between 200 and 400 years. The limiting factor to growth is available soil moisture. Increasing temperatures leads to more available water early- and late-season but a decrease in mid-season when temperatures are the highest. Although models have limitations and assumptions, they can be good prediction tools. The results of this article suggests that forests will change but eventually reach and equilibrium, yet there are factors outside of the model that can influence forest succession. A problem when talking about succession is that succession is a botanical term. The animal community must also be considered as animals can alter an ecosystem.
Adam Warrix 