ABSTRACT
The secondary deciduous broad-leaved forests in northeastern China were generally regenerated from the disturbed broad-leaved Korean pine forests, which are widely distributed in Changbai Mountains area. To understand their composition, structure and stability, a 5.76 hm2(240 m × 240 m) forest plot was established in the Mopan Mountains, Jilin Province in 2005, following the standards of the Center for Tropical Forest Science (CTFS). In this study, we analyzed the species composition, size class structure, survival curves of the main tree species and community stability of all woody plants with DBH ≥1 cm. The results showed that a total of 13368 individuals with DBH ≥1 cm were found, belonging to 39 species, 31 genera and 19 families. There were 12 species with importance value ≥1. The species composition was complex, with obvious characteristics of mixed broad-leaved forest. The abundance varied significantly among different species. The rare species and occasional species accounted for 23.1% and 43.6% of the total number of the species, respectively. The size distribution of all individuals showed a reverse "J" shape, which indicated that the community was in a stable and normal growth status. Fraxinus rhynchophylla, Quercus mongolica, Acer mono, and Maackia amurensis out of the six major species fitted reverse "J" form, Juglans manshurica showed an approximately normal distribution, and Ulmus japonica showed a "L" shape distribution. The survival curves of the six major tree species showed that the populations of F. rhynchophylla, Q. mongolica, A. mono, and M. amurensis were stable, J. mandshurica was declining, and U. japonica was growing. Results from the stability analysis of M-Godron indicated that the community was relatively stable at present.
Subject(s)
Forests , Quercus , China , Pinus , TreesABSTRACT
OBJECTIVE: To describe a novel technique for application of a Seprafilm (modified hyaluronate-carboxymethylcellulose) barrier laparoscopically, and to assess the adequacy of coverage of desired sites. DESIGN: Retrospective cohort study. SETTING: University tertiary hospital. PATIENT(S): One hundred twenty-seven patients who underwent fertility-sparing laparoscopic surgery. INTERVENTION(S): The Seprafilm was rolled up in a plastic package, then delivered through the main trocar. It was unrolled and positioned to cover the traumatized surface of the uterus, ovaries, and tubes. During application, the pelvis was photographed, videotaped, and the pictures were reviewed by two surgeons. MAIN OUTCOME MEASURE(S): The adequacy of the application was divided into three levels as to whether the Seprafilm could cover all the traumatized surfaces. RESULTS: Of the first 15 patients, 4 of 15 (26%) had successful coverage of the traumatized surface with the first sheet of Seprafilm. Of the following 112 patients, 97 of 112 (86.5%) had successful coverage with the first sheet. The success rate climbed to 96% after the second or third sheet. The average time for the application of six pieces (one sheet cut into six pieces) was 21 +/- 4 minutes. The posterior cul-de-sac is difficult to apply well. CONCLUSION(S): It is feasible to apply the antiadhesion barrier Seprafilm laparoscopically. Further studies will be needed to assess the efficacy of reducing adhesion following such use.
