STUDY ON THE TOLERANCE OF WOODY-PLANTS TO MERCURY
Lin Zhiqing Huang Huiyi (Institute of Applied Ecology, Academia Sinica, Shenyang)
The simulating tests by using soil and solution cultivation showed that annual woody-plants have certain tolerance to mercury and the tolerant capacity varies with different tree species. The order is as follows.populus canadenstspopulus xeura-mericanasalix matsudariapopulus nummowiczii.In the P.canadensis, the tolerant threshold cocentration to mercury is about 95-100ppm and the maximum absorbed amount of mercury is about 6779Hg. Above the threshold, the growth and development of the plants appear evident injures. The affinity adsorption of root cell wall to mercury, the rising of dehydrogen ase activities in root system,and the increase in the amount and the spectral band of peroxidease series may be directly or indirectly helpful for woody-plants to inciease Hg-tolerance.