Final Report - Asian Development Bank

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TA 4721-PRC: Preparing the Shaanxi-Qinling Mountains Integrated Ecosystem Management Project
Final Report Appendix 5
3.4.1.3 Coniferous Broadleaved Mixed Forest
Coniferous broadleaved mixed forest is a special vegetation type with transitional character and
unstable composition in which the invading of coniferous canopy species form after the deciduous
broadleaf forest is destroyed. The vegetation type occurs at elevations from 900–2300 m. The
dominant coniferous canopy species are Pinus armandii, Pinus taebulaeformis and Platycladus
orientalis. The broadleaved canopy species are mainly Populus davidiana, Castanea mollissima,
Quercus aliena var. acuteserrata, Litsea pungens, Toxicodendron vernicifluum, Juglansca thayensis,
Sorbusa lnifolia and Quercus dentate. Quercus aliena var. acuteserrata is in the ascendant of the
canopy, with abundant trees and young seedlings. The characteristic explanation is that the
population of Quercus aliena var. acuteserrata is well adapted to seed dispersal and is a colonizing
type. The second dominant species is Populus davidiana which is a pioneer species in succession
course of plant community.
There are Spiraea fritsichiana, Rubus sp., Rosa sp., Euonymus alatus, Berberis sp., Smilax sp. and
Viburnum betulifolium in the shrub layer. Because it colonizes after the original forest is damaged,
Sinarundinaria nitida may affect the renewal of mostly tree.
3.4.1.4 Coniferous Forest
Platycladus orientalis forest
This forest type occurs at elevations from 500–1100 m where the soil is typical brown soil and pH
value is 7�8. The annual temperature is 7.6 and annual precipitation is 886 mm in the forest zone.
Platycladus orientalis commonly form second natural pure forests which present patchy distribution,
continuous or discontinuous strap shape and are commonly associate with farmland. Platycladus
orientalis mixed growth with deciduous broadleaf on lightly degraded lands, but forms clumps of pure
forest on severely degraded sites.
The forest cover is sparse; forest structure is simple and canopy closure is 0.35�0.50. The basic
species is Platycladus orientalis growing to about 4 m. The companion tree species are Quercus
variabilis, Quercus acrodonta, Hemiptelea davidii, Quercus baronii and Pteroceltis tatarinowii. There
are Campylotropis macrocarpa, Acer grosseri, Cephalotaxus sinensis, Litsea pungens, Deutzia
discolor, Pittosporum rehderianum, Euonymus venosus, Lespedeza bicolor, Rosa multiflora var.
cathayensis, Rubus corchorifolius, Viburnum shensianum and Amorpha fruticosa in the shrub layer.
The herbaceous species are richn and dominated by Arthraxon hispidus, Cyperus diformis, Allium
senescens, Polygonum alatum, Gypsophila oldhamiana, Epimedium sagittatum, Sanquisorba
officinalis, Anthriscus sylvestris, Trachelospermum jasminoides, Lithospermum zollingeri and
Teucrium tsinlingense.
Abies fargesii forest (dark coniferous forest zone)
Abies fargesii occurs at elevations from 2500–2900 m in Guangtou Mountain and Shouyang Mountain.
The humidity is high; the humus layer is deeper and the soil is hill cineration dark palm. The
superstratum canopy species are Abies fargesii and Betula utilis, but Abies fargesii is dominant and its
color is dark green. Canopy closure is about 0.8. There are all levels big trees and young seedlings
of Abies fargesii, which show the population of Abies fargesii is stabile. Because there are only large
trees and no young seedling of Betula utilis, the population is declining. There are few shrubs in the
forest including Rosa tsinglingensis, Spiraea alpine, Sinarundina rianitida.
The life-type registers of Abies fargesii forest give priority to the geophytes which number more than
phaenerophytes and hemicrytophytes. This reflects that the environment is colder and wetter.
Larix chinensis forest
Larix chinensis occurs at the peak of the north slope in Guangtoushan Mountain and at elevations of
2900 m and above. There are mostly rocks on the ground on these sites. The forest soil is hill dark
palm soil and the community is single species. The forest is mostly found on shaded slopes and semishaded
slopes. Generally some Larix chinensis trees have died in any stand. There are few shrubs.
The herbaceous species are Androsace sp., Oxalis sp., Cardamina sp., Gentiana sp..