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COMMUNITY COMPOSITION AND TREE POPULATION STRUCTURE IN UNDISTURBED AND DISTURBED TROPICAL SEMI-EVERGREEN FOREST STANDS OF NORTH-EAST INDIA
Dominance Species diversity Floristic composition Forest structure Girth class
2010/3/26
Species composition, density, importance value index, diversity, dominance and tree population
structure were studied in disturbed and undisturbed stands of tropical semi-evergreen forest in Lunglei ...
Study on DBH-structure of Populus euphratica and Their Spatial Distribution in the Lower Reaches of the Tarim River
胸径结构 胡杨 塔里木河 林木分布
2009/11/18
采用“面”上宏观调查与“点”上典型研究相结合, 集中对塔里木河下游阿拉干断面100 hm2的胡杨(Populus euphratica)林木分布与胸径结构进行了调查。结果发现, 在距河道0-20 m的范围内, 胸径为0-4 cm的幼龄胡杨占最多, 达到13.24%。以后随着离河道距离的增加, 幼龄胡杨所占比例逐渐减小。胸径分布范围简单, 胸径为16-36 cm的林木株数在胡杨林中所占的比例最多。另...
冻融循环对甲壳素凝聚态结构和脱乙酰反应的影响（Effects of Freezing-thawing Cyclic Treatment on Condensed State Structure and N-deacetylation of Chitin）
甲壳素 冻融循环处理 N-脱乙酰反应
2009/11/3
甲壳素和质量分数为40%的浓NaOH溶液的混合物在-18℃和40℃条件下反复进行冻融处理，结果表明慢速冷冻加低温解冻的冻融循环处理过程中，冰晶的反复形成和重结晶能够破坏甲壳素凝聚态特别是晶态结构。经过3次冻融循环处理，可使甲壳素在NaOH溶液中完全溶解，获得甲壳素最终质量分数为4%，NaOH最终质量分数约为10%的均相溶液，为用均相脱乙酰法制备半脱乙酰水溶性甲壳素提供前提。
Differential Sensitivity of Rice Cultivars to Salinity and Its Relation to Ion Accumulation and Root Tip Structure
Casparian band Ion accumulation Rice (Oryza sativa L) Root tip Salinity resistance Sodium chloride (NaCl)
2010/3/4
Effects of NaCl on the growth, ion content, root cap structure and Casparian band development were examined in four rice (Oryza sativa L.) cultivars with different salt resistance (salt-sensitive indi...
Phylogeography and Population Structure of the Pine Sawyer Monochamus alternatus
dispersal genetic structure microsatellite mitochondrial DNA variation
2009/8/28
Although geographical variation was proposed for morphological, physiological and ecological traits of Monochamus alternatus, there has been no information about its genetic structure. Recent progress...
Relationship between Stand Structure of a Secondary Forest on the Keihanna Hills and Soil Hardness
cluster analysis Osaka group Pinus densiflora Quercus serrata soil hardness
2009/8/27
The stand structure of a secondary forest established on the Osaka group and related factors were analyzed. Twenty-seven quadrats were set in the forest, and every tree in those quadrats was measured....
Structure and Growth in an Old-growth Sugi (Cryptomeria japonica) Forest in Akita Prefecture,Northeastern Japan
old-aged forest old-growth sugi forest periodic annual net increment stand structure thinning operation
2009/8/27
Periodic annual net increment of stand volume and stand structure dynamics were analyzed by using data collected in long-term monitoring during a 77-year period in a sugi (Cryptomeria japonica) natura...
The Relationship between Slope Position and Stand Structure of an Old Chamaecyparis obtusa Plantation in Northern Kyoto Prefecture,Japan
L-function old-aged forest plantation slope thinning
2009/8/24
We analyzed the size and spatial distribution of trees in relation to slope position in a 90-year-old Chamaecyparis obtusa plantation, which has never been thinned. The study plot was on a steep slope...
Relationship between Stand Structure and Damage Rate in Japanese Larch Forests Damaged by Glaze
diameter distribution discriminant analysis glaze damage slenderness ratio stand density control diagram
2009/8/24
Data on the Japanese larch (Larix kaempferi Carr) forest damaged by glaze in Hidaka Hokkaido in February 2004 was analyzed to work toward developing a system that minimizes glaze damage. The distribut...
Influence of a Fagus crenata Plantation with Different Weeding Periods on the Consequent Stand Structure in Cold Region with Snowiall
colonized broadleaved species Fagus crenata plantation weeding
2009/8/24
In cold regions with snowfall in Japan, unsuccessful Cryptomeria japonica plantations are often intended to convert into more natural forest in recent years. To improve such a practice, we examined ef...
Genetic Variation and Genotype-environment Interaction in Annual Ring Structure in Progeny Test of Plus Trees of Sakhalin Fir (Abies sachalinensis)
annual ring structure genotype-environment interaction heritability x-ray densitometry
2009/8/24
For improving the wood properties of Sakhalin fir (Abies sachalinensis) variation in annual ring structure and genetic variation in different environments were examined by X-ray densitometry. The spec...
Dynamics of Multi-stem Clump Structure of Canopy Trees Affects the Change in Stand Structure of Secondary Lucidophyllous Forests
multi-stem clump structure stratification stand structure succession light environment
2009/8/24
We investigated stand and multi-stem clump structure of nine stands of secondary lucidophyllous (warm-temperate natural evergreen) forests with different ages to clarify the effects of the dynamics of...
Mosaic Structure of Riparian Forest Vegetation in the Valley Bottom of the Yubiso River,Japan,with Reference to Stand Formation of Threatened Species,Salix hukaoana
conservation disturbance regime floodplain Salix hukaoana topographic unit
2009/8/24
This study examined the environmental conditions that were required to maintain a threatened species, Salix hukaoana. Twenty-five plots were set up in the riparian zone along the Yubiso River, and for...
Relationships between Browsing on Dwarf Bamboo (Sasa nipponica) by Sika Deer and the Structure of Ground Beetle (Coleoptera: Carabidae) Assemblage
deer browsing carabid beetle indirect effect Mt.Ô daigahara pitfall trap
2009/8/21
An overabundance of Sika deer (Cervus nippon) at Mt. Ôdaigahara, in west-central Japan has necessitated the introduction of exclusion fences to protect forest decline from excessive feeding dama...
Changes in Stand Structure after the Mass Mortality of Oak Trees in Keihoku Area,Kyoto City,Japan
broad-leaved secondary forest mass mortality of oak trees Qurcus crispula regeneration succession
2009/8/21
The effect of mass mortality of oak trees, caused by the fungus Raffaelea quercivora, on the stand structure of a broadleaved secondary forest was investigated in a stand located in northern Kyoto Cit...