Climate Change Research at the University of Western Sydney.
There are many claims that because plants absorb CO2 the world would benefit from increased CO2 in the atmosphere. The University of Western Sydney has been conducting research into the behaviour of plants with enhanced CO2 and there are many research projects under-way at any one time, I was shown round the University by Assoc. Prof Paul Holford and my summary of the different experiments are as follows.
A greenhouse controlled environment growing cotton with enhanced or ambient CO2; plentiful water or drought; with and without extra nutrients; and temperature control. In the six chambers of the greenhouse the plants are grown with combinations of enhanced CO2, water and nutrients so that every combination can be tested. A quick summary of the results was that the cotton plants respond well to enhanced CO2 but unless they get more water and nutrients they cannot take advantage of the boost. If water or nutrients are restricted then the plants will not grow no matter how much CO2 they get.
A similar experiment called Whole of Tree was conducted in another part of the University. Using six large large greenhouses that would house a whole tree in a controlled environment, the trees could have, in different greenhouses, CO2 at 600 ppm or at ambient level of 400 ppm, combined with plentiful water or natural rainfall levels and they could have enhanced nutrients. A tree can be planted and grown for eighteen months before it becomes too large. During this time sensors can be attached to the tree, including the roots, and the growth and behaviour monitored and there could be as many as sixty experiments being carried out at once. The result was much the same as with the cotton in that CO2 does enhance growth but if the additional water and nutrients are not supplied to fulfil the plants requirements the tree cannot take advantage of the stimulant.
The most expensive experiment was the Free Air Carbon Enrichment (FACE) project where a natural area of woodland was surrounded by towers that blew CO2 out to raise the level to 600 ppm. This project is intended to find out what would happen when trees, which are adapted to live in a world of CO2 at 280 ppm, live in a world where the CO2 had reached 600 ppm. This is a ten year experiment which is halfway through its term and the first papers are only just being prepared now. Early results show that the trees grew quickly initially but the control plants in a natural environment eventually caught up and became the same size.
The biggest and longest running research at UWS Involved growing trees in blocks in a natural environment but with the ability to provide additional water or nutrients in a series of combinations.
The most striking result that I could see was that the addition of water stimulated growth above everything. You can see the larger trees in the centre. It must be remembered that this is Australia which is fairly dry but the trees are adapted to this climate. The other striking result was that putting nutrient on the ground, but without the benefit of additional water, stimulated the grass to grow but the trees did not benefit.
Trees are adapted to the conditions where they grow and are sensitive to change, if the climate in which they are located changes their is a strong chance that they may not survive,
Trees are adapted to the conditions where they grow and are sensitive to change, if the climate in which they are located changes their is a strong chance that they may not survive,
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