Valley Spruce-fir Forest Recession In The Context Of Climate Change, Pest-related Research

This article is chaired by Professor Wang Qinggui the National Natural Science Foundation of China,"the context of climate change, mountain valley in eastern Heilongjiang decline mechanism of spruce fir forest"(30970487) part, we use the conventional method of ecological field data collection, systematic analysis of the background conditions of climate change spruce-fir forests of the valley under the recession and the correlation between pest and concluded as follows:(1) From pathogen separation analysis of results shows, its regularity is not strong, white-rot fungus and brown rot bacteria may occur alone, but also may mix to occur, From the symptoms on look, death strains of the decadent heartwood very heavy, for the tree of final death will be a greater role. In addition, the number of death, according to analysis of visible, although there are part of the decadent bacteria happening, but symptoms are not very serious, trees have been killed, but wood material preservation is good, this means that the death of spruce decadent bacteria have a certain relationship, but not directly the dominant factors.(2) Ips sexdentatus,Monochamus urussovi Fisch,Ips typographes L,Monochamus sutor are causing Monochamus red one of main pests, spruce recession population density is larger, drug-infested. But this several pests of times incoming pests, not the direct cause of death red one spruce, because these times incoming pests rarely invade healthy trees, also hard to in healthy forest tree multiply. Only the trees extremely weak after it gradually been invaded and interference, and to multiply, accelerate the trees decline rate.(3) Spruce fir forest growth state mycorrhizal type present significant correlation, health spruce mycorrhizal type very much (17), and grow weak and death on the spruce mycorrhizal type significantly reduce (respectively 7 species and 6), different growth state of spruce mycorrhizal type is not identical also, each growth state of spruce has its unique mycorrhizal type. In addition, different growth state of spruce advantage mycorrhizal type also not identical. The advantage of healthy spruce mycorrhizal mostly for the branch complex, mycorrhizal system bigger, usually has bacterium of cable type; Spruce and death and dying spruce advantage bacterium roots type usually branch simple (not even branch), mycorrhizal system, lesser, usually don't have bacterium suo. Mycorrhizal show recession trend and the consistency of the spruce recession trend, from some kind of meaning can conclude mycorrhizal recession may be spruce death one important reason, but there is a need for more in-depth research, and generate Wang Qinggui and GaoXingxi (2006) research results are consistent.(4) This is the first will ISSR this new technology is introduced into the spruce genetic variation studies, many immature technology link. Through amplified technology and the preliminary research, ISSR technology that spruce 10 different geographical provenance only occurred within variation, belongs to the category of inner genetic polymorphisms, still not produce new varieties. Thus, spruce recession has not caused by the different limit of geographical provenance occurred within mutation. Therefore, spruce recession wood limited to external performance - significant growth is abate, and species itself does not take place in the inner of variation.(5) Spruce growth state mycorrhizal type present significant correlation, health spruce mycorrhizal type very much (17), and grow weak and death on the spruce mycorrhizal type significantly reduce (respectively 7 species and 6), different growth state of spruce mycorrhizal type is not identical also, each growth state of spruce has its unique mycorrhizal type. In addition, different growth state of spruce advantage mycorrhizal type also not identical. The advantage of healthy spruce mycorrhizal mostly for the branch complex, mycorrhizal system bigger, usually has bacterium of cable type; Spruce, death and dying spruce advantage bacterium roots type usually branch simple (not even branch), mycorrhizal system, lesser, usually don't have bacterium suo. Mycorrhizal show recession trend and the consistency of the spruce recession trend, from some kind of meaning can conclude mycorrhizal recession may be spruce death one important reason, but there is a need for more in-depth research.