Effects of different Indole-3-Buteric Acid (IBA) concentrations (0, 1 000, 1 500 and 2 500 ppm) and curing types (soft wood, semi hard and hard wood) of plane tree were investigated with Randomized Complete Bloc...Effects of different Indole-3-Buteric Acid (IBA) concentrations (0, 1 000, 1 500 and 2 500 ppm) and curing types (soft wood, semi hard and hard wood) of plane tree were investigated with Randomized Complete Block Design (RCBD) at the Agricultural research station, Charsadda. The maximum survival percentage, plant height (cm), root length (era), numbers of roots and root weight per cutting were significantly higher in hard wood cuttings. IBA concentration had no speculative effect on plane tree cuttings. Thus, hard wood cutting was the best choice for plan tree propagation.展开更多
【目的】分析影响华北土石山区侧柏水分利用的主导因子,为气候变化背景下中国侧柏人工林的经营管理提供参考。【方法】采用稳定碳同位素比值δ^(13)C计算侧柏水分利用效率(intrinsic water use efficiency,WUEi),结合温度、降雨量、相...【目的】分析影响华北土石山区侧柏水分利用的主导因子,为气候变化背景下中国侧柏人工林的经营管理提供参考。【方法】采用稳定碳同位素比值δ^(13)C计算侧柏水分利用效率(intrinsic water use efficiency,WUEi),结合温度、降雨量、相对湿度、干旱指数(standardized precipitation evapotranspiration index,SPEI)、水热状况协同性等气候指标,分析华北土石山区侧柏WUEi变化特征及其对气候变化的响应。【结果】侧柏树轮δ^(13)C与WUEi均呈现上升趋势,年平均值分别为-23.53%和87.08μmol⋅mol^(-1),年平均增幅分别为0.09%和1.17μmol⋅mol^(-1)。在月尺度上,侧柏WUEi与上年7月、9—12月和当年1—12月温度呈显著正相关,与上年6—7月、12月和当年1—12月SPEI呈显著负相关,与上年8月和当年3—5月、8月相对湿度呈显著负相关,除与上年12月降雨量呈显著负相关关系外,与其他各月降雨量均无显著关系。在年尺度上,WUEi与温度呈极显著正相关,与SPEI及相对湿度呈极显著负相关,与降雨量无显著关系。侧柏WUEi对温度和降雨量的敏感性在14.12~<15.04℃和545.97~<762.43 mm时达到最高,分别为17.87%和21.88%;当水热协同性在0.992~0.998时,WUEi对其敏感性为17.30%。【结论】温度是影响华北土石山区侧柏WUEi变化的最主要气候因子,随着温度与降雨量协同性的增强,侧柏WUEi对水热协同作用的敏感性呈升高趋势,降雨量间接影响侧柏WUEi。展开更多
文摘Effects of different Indole-3-Buteric Acid (IBA) concentrations (0, 1 000, 1 500 and 2 500 ppm) and curing types (soft wood, semi hard and hard wood) of plane tree were investigated with Randomized Complete Block Design (RCBD) at the Agricultural research station, Charsadda. The maximum survival percentage, plant height (cm), root length (era), numbers of roots and root weight per cutting were significantly higher in hard wood cuttings. IBA concentration had no speculative effect on plane tree cuttings. Thus, hard wood cutting was the best choice for plan tree propagation.
文摘【目的】分析影响华北土石山区侧柏水分利用的主导因子,为气候变化背景下中国侧柏人工林的经营管理提供参考。【方法】采用稳定碳同位素比值δ^(13)C计算侧柏水分利用效率(intrinsic water use efficiency,WUEi),结合温度、降雨量、相对湿度、干旱指数(standardized precipitation evapotranspiration index,SPEI)、水热状况协同性等气候指标,分析华北土石山区侧柏WUEi变化特征及其对气候变化的响应。【结果】侧柏树轮δ^(13)C与WUEi均呈现上升趋势,年平均值分别为-23.53%和87.08μmol⋅mol^(-1),年平均增幅分别为0.09%和1.17μmol⋅mol^(-1)。在月尺度上,侧柏WUEi与上年7月、9—12月和当年1—12月温度呈显著正相关,与上年6—7月、12月和当年1—12月SPEI呈显著负相关,与上年8月和当年3—5月、8月相对湿度呈显著负相关,除与上年12月降雨量呈显著负相关关系外,与其他各月降雨量均无显著关系。在年尺度上,WUEi与温度呈极显著正相关,与SPEI及相对湿度呈极显著负相关,与降雨量无显著关系。侧柏WUEi对温度和降雨量的敏感性在14.12~<15.04℃和545.97~<762.43 mm时达到最高,分别为17.87%和21.88%;当水热协同性在0.992~0.998时,WUEi对其敏感性为17.30%。【结论】温度是影响华北土石山区侧柏WUEi变化的最主要气候因子,随着温度与降雨量协同性的增强,侧柏WUEi对水热协同作用的敏感性呈升高趋势,降雨量间接影响侧柏WUEi。