Carbon sequestration potential of ecosystem of two main tree species in Northeast China PHYSIOLOGICAL CHARACTERISTICS OF PURE ARTIFICIAL LARIX OLGENSlS FOREST AND ITS MIXED FOREST WITH NATURAL FRAXINUS MANDSHURICA RUPR.MIXED FOREST COMPATIBLE DYNAMIC MODEL STUDIES ON COEFFICIENT OF VARIATION OF DIAMETER FOR THINNED AND UNTHINNED EVEN-AGED STANDS STUDY ON CHARACTERISTICS OF PHYSIOLOGICAL ECOLOGY OF LARIX OLGENSIS HENRY FROM DIFFERENT GEOGRAPHICAL PROVENANCES RELATIONSHIP BETWEEN HORMONE CONTENT AND GROWTH IN LARIX OLGENSIS HENRY AND ITS APPLICATION IN EARLY SELECTION STUDY ON PHYSIOLOGICAL INDICES OF CLONE SELECTION IN LARIX OLGENSIS HENRY NITROGEN NUTRITION AND ITS RELATIONSHIP WITH GROWTH IN LARIX OLGENSIS HENRY