[experience model for self-thinning process of even-aged pure stands].based on the famous -3/2 power rule and generalized schumacher growth equation, a mathematical model for the density change of even-aged pure stands with time during self-thinning process was presented, and the genetic algorithms was used to fit this nonlinear model. with the collected data from populus tremula var. davidiana, pinus yunnanensis and cunninghamia lanceolata even-aged pure stands, the new model was verified and compared with other models. the results showed that the new model could ...200515852914
[root biomass of different stand-age pinus yunnanensis forests and its distribution pattern in different soil depths].with average-tree-specific sampling method, the authors measured the root biomass of pinus yunnanensis forests with different stand ages in yongren county, yunnan province. the results indicated that total root biomass increased from 8.50 t x hm(-2) in young stand (15-17 yr) to 11.70 t x hm(-2) in middle-aged stand (30-32 yr), and to 18.91 t x hm(-2) in mature stand (60-130 yr). among different stand age classes, the biomass of coarse roots (>10 mm) varied greatly (1.5-12.3 t x hm(-2)), whereas ...200515852950
composition of gum turpentine of pines. xxx. a report on pinus serotina, pinus tenuifolia, and pinus yunnanensis. 195813549283
[effect of temperature on resistance of pinus yunnanenensis to inoculation with leptographium yunnanense, a pathogenic fungus associated with tomicus piniperda].the study showed that temperature had an important effect both on the resistance of pinus yunnanensis and on the growth and virulence of leptographium yunnanense, a pathogenic fungus associated with tomicus piniperda attacking pinus yunnanensis, which would result in the competence variation between them: at lower (< 10 degrees c) and higher temperature(> 30 degrees c), the growth and virulence of l. yunnanense were inhibited, while at 15 degrees c-30 degrees c, the resistance of pinus yunnanens ...200314986380
a novel phenolic compound from pinus yunnanensis.a rare type of phenolic compound, namely, planchol e (1), was isolated from the cones and seeds of pinus yunnanensis together with 16 known abietane diterpenoids (2-17). the structure of planchol e was established on the basis of extensive spectroscopic analysis, and it was found that the new compound did not show cytotoxic activity against several cancer cell lines.201121534040
[analysis of pine pollen by using ftir, sem and energy-dispersive x-ray analysis].infrared spectroscopy (ir), scanning electron microscope (sem) and energy-dispersive x-ray analysis (edx) were used to analyze nutrients in four pine pollen powder samples. the ir fingerprints showed that each of the samples, pinus massoniana, pinus yunnanensis, pinus tabulaeformis, and pinus densiflora, respectively had its own characteristic infrared spectrum. based on the difference of the relative intensity of those characteristic absorption peaks, the ir fingerprints can be used for the ide ...200516499047
[ecological restoration effects of typical manmade ecosystems and relationships between restoration variables in middle yunnan area].this paper studied the restoration effects of pinus yunnanensis forest, mixed eucalyptus maideni-acacia meamsii forest, eucalyptus maideni forest and restored natural vegetation in middle yunnan area. the man-made forests consisting of different tree species had different effects on plant diversity, forest hydrology, soil surface erosion control, soil amelioration, and forest characteristics. afforestation with native species promoted the plant diversity. recovery distance index(rdi) was calcula ...200314732995
[plant diversity of different replaced communities after eupatorium adenophorum removal].plant diversity of different replaced communities after eupatorium adenophorum removal. wang in this paper, an investigation on the structure, species composition and plant diversity of replaced communities after the removal of invasive e. adenophorum at the beginning of 1980s was made in the shuangbo county of yunnan province, with local aged pinus yunnanensis and unmanaged e. adenophorum forests as the reference. the results showed that in replaced communities, the richness, shannon-wiener, si ...200616724727
response of tomicus yunnanensis (coleoptera: scolytinae) to infested and uninfested pinus yunnanensis bolts.tomicus yunnanensis kirkendall and faccoli (coleoptera: curculionidae: scolytinae) is a newly described pine shoot beetle found in southwestern china. this beetle has affected >200,000 ha of pinus yunnanensis (franchet) forests over the past 30 yr. after maturation feeding in the shoots, adults attack the boles in december to produce a new generation. a hanging bolt study was initiated in november 2006 to detect the beetle flight patterns and to test if dispersing beetles respond to infested and ...201020214373
seasonal water stress and the resistance of pinus yunnanensis to a bark-beetle-associated fungus.we examined the influence of seasonal water stress on the resistance of pinus yunnanensis (franch.) to inoculation with leptographium yunnanense, a pathogenic fungus associated with the aggressive bark beetle, tomicus n. sp. experiments took place between october 1997 and november 1999 in two plots located at the top and at the foot of a hill in shaogiu, china, a region characterized by dry winters and wet summers. following isolated and mass fungal inoculations, we observed the reaction zone le ...200818316300
chromosomal localization of 5s and 18s-5.8s-25s ribosomal dna sites in five asian pines using fluorescence in situ hybridization.fluorescence in situ hybridization (fish) was employed on mitotic metaphase chromosome preparations of five asian pinus species: pinus tabuliformis, pinus yunnanensis, pinus densata, pinus massoniana and pinus merkusii, using simultaneously dna probes of the 18s rrna gene and the 5s rrna gene including the non-transcribed spacer sequences. the number and location of 18s rdna sites varied markedly (5-10 pairs of strong signals) among the five pines. a maximum of 20 major 18s rdna sites was observ ...200312582844
enhanced drought-tolerance in the homoploid hybrid species pinus densata: implication for its habitat divergence from two progenitors.the homoploid hybrid species pinus densata is restricted to alpine habitats that exceed the altitude range of its two parental species, pinus tabulaeformis and pinus yunnanensis. alpine habitats usually generate cold-induced water stress in plants. to understand the ecological differentiation between these three species, we examined their physiological responses to drought stress. potted seedlings of three species were subjected to low, mild, moderate and severe water stress in an automatic-cont ...201019804499
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