*How can we measure the rate of exudation and also determine the composition of exudates*
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☆Answer☆
In the field of allelopathy they would develop a leachate collection system. The leachates can be used to irrigate test crops and also chemically analyzed for their characterization both qualitatively and quantitatively. Exudates after understood for their nature can be put into dose response experiments. One of very difficult areas would be understanding the single chemical responses may not reflect the complex mixtures in these systems. For your intension of looking at soil processes you may want to look at soil aggregation especially soil aggregate stability and see how the allelochemics could influence that critical process. When soil become persistently aggregated the result is greater conservancy of soil carbon which could be critical for water aire relations and the ability to positively sequester significant amounts of carbon and nitrogen. Hope some of these thoughts might be helpful in your research goals.
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