Understanding the relationship between climate and growth at different heights gives insight into the mechanisms by which trees respond to climate change. In this paper, tree鄄ring data at different heights (0.3, 1.3, 4, 10, 15, 20, and 25 m,) on the north side of Korean pine (Pinus koraiensis) trees on Changbai Mountain were collected from 155 cores, taken from 25 Korean pine trees. Dendrochronology and a multiple comparison method (LSD) were used to analyze the radial growth characteristic and the climate鄄growth relationship. The results show that the trends in annual radial growth of Korean pine at different heights were essentially identical. Apart from an abnormal increase in the annual radial growth at a height of 20 m around 1980, the annual radial growths at other heights showed a downward trend. The most obvious variations were found at the base (0.3 m and 1.3 m) and crown (20 m) of Korean pines. With increasing tree height, the annual growth rates at different heights were all reduced. The maximum growth rate was observed at a height of 0.3 m, which

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Arbuscular mycorrhizal fungi (AMF) is one of the most widely spread micro鄄organisms, which could form symbiotic associations with most of the vascular plants in natural or artificial ecosystems. Previous reports revealed that AMF could promote the growth of plant by improving the utilization rate of nutrients of plants. Therefore AMF is receiving more and more attention from domestic and overseas researchers. As a new microbial fertilizer, AMF is expected to play an important role in the reduction of chemical fertilizer and be further used in controlling the pollution in natural water bodies. Wheat is one of the most important economic crops, especially in China, which is the major food crop only behind rice. Therefore, the efforts to maximize the production of wheat by applying the minimum chemical fertilizer have dual significances both in economy and ecology. In this research, we selected two species of native AMF in the field as inocula, GM (Glomus mosseae) and GI (Glomus intraradices). By investigating the status of wheat in different growth periods, we study the effects of AMF on the ultilization rate of nitrogen and phosphorus of wheat and the final effects on the production. The results indicated that the roots of wheat could be infected by AMF in natural field ecosystem, In addition, the artificial application of AMF could significantly improve the infection rate of AMF on wheat. The infection rate could be increased by 24.54% by inoculating GM and 21.93% by GI. Moreover, the height of wheat and the aboveground biomass were increased through inoculating GM by 14.08% and 23.5%, respectively; the height of wheat and aboveground biomass was increased through inoculating GI by 13.57% and 21.7%, respectively. The results also indicated that the plant height and biomass changes comply with logistic curve. According to the curve, we found that AMF could promote plants忆 growth, particularly on roots. Specifically, the effect of GM was more effective than GI in the present research. The content of phosphorus in soil reached the peak level on the 120th day. The variable quantity of phosphorus in soil without the infliction of AMF is 6.35 mg / kg, and the absorptive amount could be increased by inoculating GM and GI to 11. 55 mg / kg and 10. 41 mg / kg, respectively. In addition, the content of hydrolytic nitrogen in soil reached the peak level during 120-150 days. However,

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