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This study was to investigate the chemical composition and the antioxidant activity of essential oils extracted from Torreya grandis cv. merrillii arils by hydro-distillation. Eighty six compounds,...

Aims Temperature is generally considered the limiting factor for tree growth at species' upper elevational limits. Our objectives were to determine the upper elevational limit response of radial growth in Pinus koraiensis and Picea jezoensis var. komarovii to climate warming in Changbai Mountain Nature Reserve of China and to eluci- date temperature sensitivity of radial growth. Methods We selected typical trees at each species' upper limit for increment coring and established ring-width chronologies for both species. We compared the general trend of the chronologies with temperatures during 1958-2006. To determine species' response to rising temperature, we analyzed the relationship between chronol- ogy and important meteorological factors (temperature, precipitation, growing season length, effective accumula- tive temperature, etc.) using correlation, response function, moving correlation and pointing year analyses. Important findings As temperature rose, ring widths in Pinus koraiensis exhibited the same increasing trend as temperature, while ring widths in Picea jezoensis var. komarovii exhibited decreasing sensitivity to temperature. The increase of temperature and precipitation in the growing season mutually enhance Pinus koraiensis growth. Prolongation of the growing season and rising temperature during the growing season also can accelerate the growth of Pinus koraiensis. For Picea jezoensis var. komarovii, water stress caused by increasing temperature is the main reason for its relationship between ring width and temperature. Correlations between Picea jezoensis var. komarovii ring width and almost all temperature indices are significantly negative. As temperature rose, correla- tions between ring width and precipitation, especially spring precipitation, changed from negative to positive. High temperature in each month and inadequate precipitation in the middle and late growing season are the im- portant meteorology conditions for narrow rings. Also, the insignificant extension of the growing season may

Fine root dynamics and turnover rate were studied by sequential soil coring method in a 60-year-old Asia white birch ( Betula platyphylla ) forest of Donglingshan Mountain, China. Biomass and necromass of both the finest ( −1 , respectively.

A greenhouse control experiment was conducted to explore the effects of nitrogen and carbon addition and arbuscular mycorrhiza (AM) on the growth of alien invasive plant Ambrosia artemisiifolia (common ragweed). Nitrogen addition had no significant effects on the morphological indices, biomass and its allocation, and absolute growth rate of A. artemisiifolia, but increased the nitrogen content in the aboveground and underground parts of the plant significantly. Carbon addition increased the content of soil available nitrogen. In this case, the biomass allocation in root system for nutrient (nitrogen) absorption promoted, resulting in a remarkable decrease of branch number, total leaf area, specific leaf area (SLA), and leaf mass ratio. As a result, the total biomass decreased significantly. The symbiosis of A. artemisiifolia and AM fungi had great influence on the common ragweed's soil nitrogen acclimation, which enhanced its resource-capture by the increase of SLA, and this effect was more significant when the soil nitrogen content was low. AM fungi played an important role in the growth of A. artemisiifolia in low-nitrogen environment.

Biochemical changes of natural actomyosin from fresh pale, soft, exudative (PSE) and normal pork were studied, and the effects of different storage temperatures and different incubation temperature and times on sample superprecipitation, total sulfhydryl (-SH) content, and ATP (adenosine triphosphate) sensitivity were investigated. The results demonstrated that ATPase activity and thermal stability of PSE actomyosin were lower than those of normal pork; and that PSE actomyosin had higher -SH content than that of normal pork at all incubation temperatures and times tested.