| To some extent, forest biodiversity is an important indicator of the forest quality change. Forest structural adjustment.as a major forest management measures, is a major factor that impacting the internal of the forest ecosystems biodiversity.it makes a change forest biodiversity, affect the ecological functions of forests. Gaps is a forest of structural adjustment, it is prevalent in forest ecosystems phenomenon, but also an important part of forest ecosystem processes, it has an important role in promoting ecosystem development.Hilly area of central Sichuan is one of the most serious soil erosion areas in the upper Yangtze River region,the area planted in the mid-1980s, a large cedar stand. Since the beginning of the planting in the region stand density is too large, coupled with the lack of stand tending the update process, resulting in a single forest structure, sparse understory plants, under the conservation of the biological diversity, ecological functions in degraded condition, the production function is very low effective state.Therefore, this paper mainly to understory plants and soil animals in forest plantations gaps of different sizes in hilly area of central Sichuan as the object, use the quadrat survey method researching understory plant diversity and soil animal diversity of natural state, artificial regeneration (the areas are 50m2,100m2,150m2 and 200m2) and comparison. The results showed that:(1) Different areas of the nature state gaps recorded 12.597 plants,54 species, belonging to 51 genera and 30 families. Shrub Total 4032 26 kinds. Which, CK is 528 13 species belonging to 12 families and 13 genera; L1 is 945 11 species belonging to 9 families and 11 genera:L2 is 774 and 15 species belonging to 13 families and 14 genera; L3 is 978 17 kinds, belonging to 13 families and 16 genera; L4 to 807 and 17 species belonging to 14 families and 16 genera. Herb total 8565,38 kinds. Which. CK to 1503,16 species belonging to 11 families and 15 genera; L1 to 1548,14 species belonging to 9 families and 13 genera; L2 to 1938,18 species belonging to 12 families and 17 genera; L3 to 2040 21 kinds, belonging to 14 families and 19 genera; L4 to 1536,17 species belonging to 15 families and 16 genera. A total of 3189 soil animals, belonging to 23 orders 4,8 classes. Which, CK is 615 belonging to 4.8 classes.15 orders:L1 is 534, belonging to four eight classes,16 orders; L2 is 744. belonging to four seven classes,16 orders; L3 is 714, divided is 4,8 classes 18 mesh; L4 is 582, belonging to 17 orders 4,6 classes. Comprehensive understory plants and soil fauna diversity index, inefficient artificial cedar forest biodiversity optimal treatment window under natural conditions may be between 50 square meters to 100 square meters.(2) Different areas of the artificial regeneration gaps recorded 14,928 plants,57 species, belonging to 52 genera and 31 families. A total of 3.669 shrubs,23 species belonging to 22 genera and 18 families. Which, CK is 528 13 species belonging to 11 families and 13 genera; L5 is 675,12 species belonging to 11 families and 12 genera; L6 to 723 11 species belonging to 9 families and 11 genera; L7 is 1035 15 kinds, belonging to 13 families and 14 genera; L8 to 708 and 15 species belonging to 12 families and 15 genera. Total 11259 34 kinds of herbs, belonging to 18 families and 31 genera. Which, CK to 1503,16 species belonging to 10 families,16 genera; L5 to 1992 19 species belonging to 12 families and 19 genera; L6 is 2448 24 species belonging to 15 families and 23 genera; L7 is 2532 24 kinds, belonging to 14 families and 23 genera:L8 to 2784 19 species belonging to 14 families and 19 genera. A total of 4281 soil animals. Which, CK is 615. belonging to 4.8 classes,15 orders; L5 is 654,belonging to 4.8 classes.17 orders:L6 of 1086. belonging to four eight classes,16 orders; L7 to 1038, divided classes are 4917 mesh; L8 of 1188, belonging to 18 orders,4, 8 classes. Comprehensive understory plants and soil fauna diversity index, artificial regeneration inefficient artificial cedar forest biodiversity optimal treatment window may be between 50 square meters to 100 square meters.(3) The study found that in the understory plant diversity, artificial regeneration gaps plant species richness were higher than the natural state gaps; Shannon wiener index and Simpson index in addition to artificial regeneration gaps of 200 square meters of forest gap slightly small, the other three processing plants were higher than the level of the natural state of the gaps; artificial regeneration 100 square meters of forest gap Pielou index is slightly smaller than the state of nature gaps, other treatment levels were greater than the natural state of the gaps. Soil animal diversity, artificial regeneration of forest gap species richness in addition to 150 square meters of forest out of the window, the other three deal with gaps larger than the state of nature; whereas addition of artificial regeneration in gaps gaps slightly larger than 200 square meters, the other three treatment plants Simpson index level is less than the natural state of the gaps,100 square meters and 150 square meters large gaps gap; Shannon wiener index, both artificial regeneration closer to 50 meters and 100 meters,150 meters gaps were smaller than in the natural state gaps, and 200 square meters of forest gap is slightly larger; artificial regeneration gaps 200 square meters plant Pielou index slightly larger gaps in the natural state, the average is less than other natural state of water treatment gaps. Several comprehensive index of biodiversity, understory plant diversity in replanting cedar wood silver Artificial regeneration in gaps in the rich more natural state, and soil animal diversity is the opposite.(4) species richness of soil animal species richness and understory plants, Shannon-wiener index, Simpson index, Pielou index correlation was not significant (P>0.05); soil animals Shannon-wiener index and understory plants species richness, Shannon-wiener index showed a significant negative correlation (P<0.01), and understory plants Simpson index showed a significant negative correlation (P<0.05), and understory plants Pielou index correlation was not significant (P>0.05); soil animals Simpson index and understory plant species richness, Shannon-wiener index, Pielou index showed a significant negative correlation (P<0.01),and understory plants Pielou index correlation was not significant (P>0.05); soil animals Pielou index and understory plant species richness, Shannon-wiener index, Pielou index showed a significant negative correlation (P<0.01), and understory plants Pielou index correlation was not significant (P>0.05).(5) For the inefficient cypress plantation gaps, species diversity index and soil animal diversity index equilibrium is the most suitable treatment, regardless of replanting native species or not, the optimal forest area in the 50 square meters to 100 square meters between, in order to conservation of biodiversity, to maintain ecosystem stability. In addition to cut down forest biodiversity conservation, reasonable thinning, with massive transformation, the upper crown thinning structure adjustment to improve forest structure, and strengthen ecological system to resist pests and diseases is the area cypress inefficient forest transformation business focus. |
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