Table 4. Comparison of the absolute number and percentage of each life form category in the drawdown area before impoundment by the Three Gorges Dam and after impoundment in both 2009 and 2010.

Life form	No. of sp.		Percentage (%)
	2009	2010	2009	2010
Phanerophytes	30	16	17.1	12.6
Chamaephytes	14	11	8.0	8.7
Hemicryptophytes	16	14	9.1	11.0
Cryptophytes	28	23	16.1	18.1
Therophytes	87	63	49.7	49.6
Total	175	127	100	100