Fire Environment Mechanism of Lightning-groundfire for Daxing''''anling Mountains

Ground fire is an igniting phenomenon that is difficult to control and lightning is the main cause of ground fire. The mechanism of lightning-ground fire is very complex. Daxing'anling Mountains forest region is the place that lighting-groundfire occurs more often and regularly. Our study on lightning-groundfire of this zone in 2002 shows: much more soil near the surface and the ground fuel is the matter preconditions of lightning-groundfire, and the weather conditions hasten the occurrence of lightning-groundfire. Especially in the conditions with low precipitation, long time drought, increasing surface temperature, relative humidity depressing and fuel dryness, lightning-groundfire is easy to occur. Lightning-groundfire has spatiotemporal character. Lightning-groundfire occurs mostly in primary forest zone, such as conifer forest, broadleaf forest, conifer and broadleaf mixed forest. Lightning-groundfire often burns slowly, for a long time and completely, and it has the characteristics of high conceal     

Assessing impact of climate change on forest cover type shifts in Western Himalayan Eco-region

Climate is a critical factor affecting forest ecosystems and their capacity to produce goods and services. Effects of climate change on forests depend on ecosystem-specific factors including dimensions of climate (temperature, precipitation, drought, wind etc.). Available information is not sufficient to support a quantitative assessment of the ecological, social and economic consequences. The present study assessed shifts in forest cover types of Western Himalayan Eco-region (700?4500 m). 100 randomly selected samples (75 for training and 25 for testing the model), genetic algorithm of rule set parameters and climatic envelopes were used to assess the distribution of five prominent forest cover types (Temperate evergreen, Tropical semi-evergreen, Temperate conifer, Subtropical conifer, and Tropical moist deciduous forests). Modelling was conducted for four different scenarios, current scenario, changed precipitation (8% increase), changed temperature (1.07°C increase), and both changed temperature and precipitation. On increasing precipitation a downward shift in the temperate evergreen and tropical semi-evergreen was observed, while sub-tropical conifer and tropical moist-deciduous forests showed a slight upward shift and temperate conifer showed no shift. On increasing temperature, an upward shift in all forest types was observed except sub-tropical conifer forests without significant changes. When both temperature and precipitation were changed, the actual distribution was maintained and slight upward shift was observed in all the forest types except sub-tropical conifer. It is important to understand the likely impacts of the projected climate change on the forest ecosystems, so that better management and conservation strategies can be adopted for the biodiversity and forest dependent community. Knowledge of impact mechanisms also enables identification and mitigation of some of the conditions that increase vulnerability to climate change in the forest sector.     

Stand development patterns of forest cover types in the natural forests of northern Baekdudaegan in South Korea

The purpose of this study was to classify current forest cover types,and to investigate stand development patterns for natural forests in six areas in northern Baekdudaegan,South Korea.Twenty-eight independent forest communities were aggregated into eight forest cover types by species composition in the overstory of each forest community.The forest cover types were of mixed mesophytic,‘‘others’ ’ deciduous,Quercus mongolica dominant,Q.mongolica pure,Pinus densiflora–Q.mongolica,P.densiflora,Betula ermanii,and Q.mongolica–P.koraiensis.The ecological information was organized by importance value and species diversity for each forest type.Based on the correlation between species diversity index and the abundance of Q.mongolica plus P.densiflora for corresponding forest cover types,we compared the developmental process and approximate successional pathway between each cover type.The P.densiflora forest cover type changes into the P.densiflora–Q.mongolica cover type,followed by the Q.mongolica dominant cover type through continuous invasion of the oak trees.Furthermore,the Q.mongolica pure cover type would spread toward the Q.mongolica dominant cover type with a mixture of various deciduous tree species.The Q.mongolica dominant cover type progresses through the other deciduous cover types to the mixed mesophytic cover type with diversified composition and structure.On the mid to lower slopes,with loamy soils and good moisture conditions,various deciduous forest types should progress,by ecological succession,toward the mixed mesophytic cover type without any further disturbance.     

Factorial analysis on forest canopy density restoration in the burned area of northern Great Xing＇an Mountains, China

The restoration of forest landscape has drawn much attention since the catastrophic fire took place on the northern slope of Great Xing‘an Mountains in 1987. Forest canopy density, which has close relation to forest productivity, was selected as a key factor to find how much the forest quality was changed 13 years after fire, and how fire severity, regeneration way and terrain factors influenced the restoration of forest canopy density, based on forest inventory data in China, and using Kendall Bivariate Correlation Analysis, and Distances Correlation Analysis. The results showed that fire severity which was inversely correlated with forest canopy density grade was an initial factor among all that selected. Regeneration way which did not remarkably affect forest canopy density restoration in short period, may shorten the cycle of forest succession and promote the forest productivity of conophorium in the future, Among the three terrain factors, the effect of slope was the strongest, the position on slope was the second and the aspect was the last.     

大兴安岭地区森林景观沿主要河流两侧分布的变化

In this paper, the regularity and changes of the forest landscape along the major rivers, namely, Nuomin River, Bila River and Zhawen River in Daxing‘ an Mountains, Bilahe Forestry Bureau based on the interpretation of TM data were studied. The results showed that the regularity has changed a lot due to the gradually stronger human intervention on forest landscape. The most obvious change was the cultivated lands had been expanding alongside the major rivers. With the increasing of population, the only way to satisfy the increasing needs of the local people for subsistence is by expanding cultivated lands because of the backwardness of agriculture productivity. The regularity of conifer distribution along rivers of 1997 has changed in the diverse direction of that of 1988. The proportion of conifer gradually increases with 1 000 m further away from the major rivers. That is due to the favorable availability of conifer alongside river bank, the most populated area in the forest region.     

STUDY ON THE NETWORK OF FOREST BURNING LINKS

Based on the research of the Forest Burning Links published in the Journal ofNortheast Forestry University in 1987,this paper continues to study the theory of forest burningFire behavior has been divided into two important series in this paper.One is fire occurrence andspread, and the other is burning intensity.The first series has been divided into three grades as A:toburn difficulty and spread slowly;B:to burn possibly and spread little fast;and C:to burn easilyand spread fast.The second series has been divided into four grades as I:light burning;Ⅱ:me-dium burning;Ⅲ:intense burning;and Ⅳ:severe burning.The firsts series can be put as ordinate,and the second series can be put as abscissa.Then the network of 12 forest burning links can beformed.In the network,the relatioship,the law of distribution and the variation of different forestburning links can be shown clearly.The studies of the distrubution of fuel types,topography,siteand fire kinds in the network can provide the basic theory for fire mana     

SITE CLASSIFICATION FOR PROTECTIVE FOREST AFFORESTATION ON THE COAST OF CHINA

Land for protective forest on the coast has special site conditions,and siteclassification is the scientific basis for seaboard afforestation.The site classification systemon the coast zone and islands of China may be classified into five levels-site region(sub-region),district,class,group,and type.The land division for afforestation is carried outby the principle of enviornmental heterogeneity among regions,sub-region and district onlarge scale,according to the difference of air temperature,moisture and type of coastgeomorphy.It may be classified into 7 regions,12 sub-regions and 55 districts.Themedium and small scaled division for site class,group and type,subdivided in a sitedistrict,are based on medium topography,topographic climate,micro-relief and soil conditions.     

Ecological Environment Change in North Slope of Qilianshan Mountains

Based on meteorological,hydrological, forest,and grassland data collected by location observation,remote sensing,field surveys and relevant literature during 1956 to 2009,the ecological environment change in northern slope of the Qilianshan Mountains was analyzed synthetically using regression and correlation analyses.The results showed that the temperature had an annual variation rate of 0.033 4℃·a^-1 in northern slope of the Qilianshan Mountains since 1960,and exhibited a raising trend,especially since 1987.The annual variation rate of annual precipitation was 0.570 2 mm·a^-1,indicating that the precipitation tended to increase.The climate had changed from arid to humid in this region since 1976.From 1956 to 2006,the glacier area of six inland river basin（Shiyanghe river,Heihe river, Beidahe river,Shulehe river,Danghe river and Halternhe river） and Datonghe river basin in northern slope of Qilianshan mountains decreased by 17.7%. Thickness of the glacier reduced about 5-20 m,and the snow line rose about 100-140 m.The Glacier ice reserves in inland river basin of Hexi decreased by 11.4%.From 1972 to 2007,27 glaciers in the eastern section of the Qilianshan Mountains disappeared.From 1956 to 2009,the runoff change in the northern slope of the Qilianshan Mountains was different in different regions.The runoff was reduced significantly in Shiyanghe river basin, increased slightly in Heihe river basin,and increased obviously in Shulehe river basin.From 1958 to 1988, the area of deforestation and farming was more than 10.0 million ha,and the forest area was reduced 0.6 million ha.Since the Qilianshan Mountain Nature Reserve was established in 1989, the forest was restoring gradually because of continual protection and cultivating,and the forest area was increased 9.4 million ha from 1989 to 2008. Due to human interference,especially over-grazing impact,the quality of the wood-land,shrub-land and grass-land in northern slope of the Qilianshan Mountains were in a degraded condition,which re     

Study and Application of Fuel-breaks in Southwest China

All of the plants can be combusted. The mechanism of forest belts resistance is that the tree species weren‘t liable to be burned compared with other plant species. In this paper new concepts on fire resistant trees and fuel-breaks trees were presented. The fire resistance mechanism includes 3 aspects, fire-resistant tree species, rational construction forest belts and environment. Tree crowns can resist fire forwarding. Forest belts can form the environment, which is not easy to fire, and also make fuels distributed discontinuous. The network of forest belts has large area of conifer forest segregated. The ideal f‘ire resistant tree species had better to embrace some characteristics, such as high f‘ire resistance, rational planting and biological characteristics.     

Dynamics of dominant tree species in a forest ecotone on the northern slop of Changbai Mountain

The competition and dynamics of dominant trees species in the forest ecotone between the broad-leaved/Korean pine （Pinus koraiensis） mixed forest and the spruce-fir forest （also known as dark conifer forest） in Changbai Mountain, Jilin Province in Northeast China were studied by using Lotka-Volterra model, based on the data from twenty-eight sample plots with area of 20 mx90 m for each one. Results showed that under natural condition, differentiation of communities followed two directions： one would be Spruce （Picea jezoensis and few P. koraiensis） and fir （Abies nephrolepis） co-dominant conifer forest, and at the equilibrium fir was absolutely preponderant （77.1% of relative dominance （RD））; the other would be the conifer and broad-leaved mixed forest, and at equilibrium, the broad-leaved tree species was 50% of RD in the broad-leaved/Korean pine mixed forest and 66% of RD in the broad-leaved and spruce-fir mixed forest. The study demonstrated that both broad-leaved/Korean pine mixed forest and dark conifer forest were climax community, the ecotone had transitional characteristics, and the diversification of the forest communities suggested that the direction of succession was affected by local habitat.     

内蒙古大兴安岭林区生态公益林建设建议

文章结合内蒙古大兴安岭林区实际 ,提出了生态公益林的划分办法 ,并针对生态公益林的经营与管理提出建议供参考     

红松引种中间试验研究

在呼伦贝尔市引种红松，其地理位置及诸多气象因子等与原产地有很大差异，因此将小兴安岭温带湿润地区的树种引种到寒带或温带半湿润的大兴安岭地区进行栽培，要经过科学的试验和采取相应的驯化措施，才能达到引种目的。本文通过在大兴安岭地区引种红松的中间试验，找到了一种适合当地栽植的方法，为今后寒带或温带半湿润地区的红松栽植提供了一条有效的途径。     

内蒙古大兴安岭林区森林资源生态效益分析

内蒙古大兴安岭林区是四大国有林区之一,是呼伦贝尔草原和松嫩平原的天然屏障。对其进行生态效益分析具有极为重要的意义。     

黑龙江省大兴安岭生态建设的对策与思路

文章介绍了大兴安岭林区生态建设的特殊性和必要性,并就如何加快大兴安岭林区生态建设工作,提出了一系列可行性建议和对策。     

Natural Mongolian Pine Forests in the Great Xing''''an Mountains,Northeast China

1 Introduction The Great Xingan Mountains in the northeast of China is covered by boreal forests. Larch (Larix gmelinii) represents the most frequent tree species. Mongolian pine (Pinus sylvestris var. mongolica) can be found on about 3% of the forested land. Pine forests contain the most valuable timber, which is harvested on large areas and transported to southern regions. Within these forests, few studies exist about the flora, the distribution of the dominating tree species, and their…     

我国主要森林生态系统类型降水截留规律的数量分析

通过对大量林林生态系统水文生态功能研究资料的分析，从林冠层、枯枝落叶层和土壤三个森林水文生态功能的发挥最主要的层次出发，比较分析了我国主要森林生态系统类型的降水截留规律。     

Allozyme markers in breeding zone designation

Early studies of allozyme variation in plant populations suggested that allelic frequencies in some loci vary by geography. Since then, the expectation that allozymes might be useful in describing geographic patterns has generally not been borne out by single locus analyses, except on the broadest scale. Multi-locus analyses reveal the converse: canonical correlation analysis of individual, uniformly-spaced genotypes describe statistically-significant, complex patterns with geography. Multi-locus scores in four major species, Abies concolor, Pinus lambertiana, P. ponderosa, and Pseudotsuga menziesii, of the mixed conifer forest in the Sierra Nevada correlate 0.40 or greater with the first canonical vector of a geographical trend surface equation. The different species follow similar patterns by latitude and elevation. In contrast with patterns in the Sierra Nevada, large-scale differentiation is weak (R ² < 0.20) among populations of Pseudotsuga menziesii in the Coast Ranges and Siskyou Mountains of northern California and southern Oregon, where differentiation may be local. For the purpose of forming zones, we subdivided scores of the first two to four canonical vectors into groups and plotted them as multidimensional contour intervals. Reclassification by discriminant analysis serves as an approximate guide to transfer risks within and among these groups.     

对内蒙古大兴安岭林区林产工业产品销售价格的思考

理顺和建立林区林产工业产品价格体系、制定相关政策、强化价格和行业管理 ,是防止企业内部有害竞争 ,营造公平有序的竞争环境 ,促进行业健康发展 ,提高林区整体经济效益的有效途径 ,是深入实施“天然林保护工程”的必要保证。本文作者着重分析了内蒙古大兴安岭林区林产工业产品销售价格的现状、存在问题 ,探讨和提出了应采取的对策和建议