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丹东柞蚕场可分为三种类型。一类柞蚕场,柞树密度较大,每667平方米150墩、株以上,长势旺盛,林相明显轮伐更新前郁闭度达0.6以上。树下草类及灌木植物茂密。以禾本科、豆科及棒等为优势种,覆盖度达75%以上。地面还有3~4厘米厚枯枝落叶层、土壤有机质含量在2.9%以上。这类蚕场保持着原有的顶极植物群落结构,生产力水平较高,亩产叶量和产茧量分别在340公斤和8.5公斤以上。此类柞蚕场面积占27.10%。二类柞蚕场,柞树和草类及灌木植物生长一般,生产力水平中等,亩产叶量和产茧量分别在260公斤和6公斤左右。三类柞蚕场,柞树树势衰弱缺株率达26%以上,轮伐更新前郁闭度在0.6以下。树下草类及灌木植物明显退化,少数旱生植物如羊胡子苔草、花木兰等成为优势种,覆盖度在55%以上。
Dandong tussah farm can be divided into three types. A tussah field, oak tree density larger, 150 pier per 667 square meters, more than strains, strong growth, forest rotation significantly before the closure of the closure degree of up to 0.6 or more. Grass and shrub plants under the tree dense. Gramineous, legumes and rods as the dominant species, coverage of more than 75%. The ground has 3 ~ 4 cm thick litter layer, soil organic matter content above 2.9%. This kind of silkworm farm maintains the original climax plant community structure, the higher the level of productivity, leaf yield and cocoon production were 340 kg and 8.5 kg respectively. Such Tussah field area accounted for 27.10%. The second category tussah farm, oak and grasses and shrubs plant growth in general, the middle level of productivity, yield per mu and the amount of cocoons were 260 kg and 6 kg. Three types of tussah field, oak tree fragility strain rate of 26% or more, the rotation before the closure canopy density closed at 0.6 or less. Grassland and shrub plants under the tree significantly degraded, a small number of xerophytes such as Carex lanceolata, Mulan, etc. become the dominant species, coverage of more than 55%.