Just as it is 'natural' for vegetation to grow ["esev mazria zera"], and for all living things to reproduce ["pru u'rvu"], it is also 'natural' for man to dominate his environment;
(man; to dominate; his environment) (vegetation; to grow; ) (it; is also; natural; for man to dominate his environment)
man vegetation it
to dominate to grow is also
his environment
natural for man to dominate his environment