The Health Assessment And Management Model Of Larch Plantation In Jingouling Forest Farm

The paper studied the concept and connotation of forest health, and summerised the research progress of forest health in China and abroad. The paper also studied larch plantation which belonged to three age groups in Jingouling forest farm, Wangqing conty, Jilin Province. Though analyzing the forest measurement factors, an assessment system of health indicators was set up to establish the health level of the larch plantation. The conclusions were:1) Tree measure factors showed regular changes with increasing age. The factor canopy density of near-mature and mature forests stayed at0.5-0.7. The tree species which occupied much in the forest accumulation were manchurian ash, Korean pine, spruce and fir except larch.2) The middle-aged forests were even distribution and the near-mature forests were reunion distribution. Mature forests were even or reunion distribution. Larch was in moderate status, and the dominant species were different between forests. While in near-mature and mature forests, larch was in sub-dominant status, and the broadleaved trees changed their moderation or inferior status to sub-dominant status.3) The diameter distribution curves of the forests were similar to normal distribution. The differences were the diameter distribution curves of middle-aged forests and mature forests had single peak, but that of the near-mature forests had multiple peaks.4) There were many natural regeneration trees in both near mature forests and mature forests. Among the regeneration trees, the number of firs was most, followed by other conifers. Broadleaved regeneration trees included acer mono maxim, manchurian ash and birch. Most near mature and mature forests existed fallen wood and stump regeneration.5) Health assessment results showed that middle-aged forests were healthy, while both in near mature forests and mature forest, some were healthy, others were half-healthy. Most forests acquired low score on the indicator of average breast diameter, and middle-aged forests achieved low in both canopy density and species composition. The mature forests showed their differences in shrub and grass cover, canopy density, species composition and the stock ratio of objective species.In addition, the paper also put forward a healthy management model of the larch plantation which aimed to support the healthy forest research in China and the forest farm in our country.