从2008年1月至12月,对华西雨屏区光皮桦（Betula luminifera）林进行了模拟氮沉降试验,应用LI-8100土壤碳通量分析系统和气压过程分离（Barometric Process Separation,BaPS）技术分别研究了4个氮沉降水平0（CK）、5（L）、15（M）、30...从2008年1月至12月,对华西雨屏区光皮桦（Betula luminifera）林进行了模拟氮沉降试验,应用LI-8100土壤碳通量分析系统和气压过程分离（Barometric Process Separation,BaPS）技术分别研究了4个氮沉降水平0（CK）、5（L）、15（M）、30（H）g N.m^-2.a^-1下土壤呼吸的日变化和月动态。结果表明,土壤呼吸具有明显的季节动态,各处理土壤呼吸最高值均出现在7月份;氮沉降初期,各处理土壤呼吸差异不明显,5月份以后各氮沉降处理土壤呼吸开始表现出抑制效应,随着施氮浓度的增加,抑制效应愈加明显（CK〉L〉M〉H）;土壤呼吸日变化基本呈现单峰曲线,呼吸速率最高值一般出现在14：00—16：00。随着氮沉降的增加,对土壤呼吸产生的抑制效应增强,这可能与光皮桦林土壤本身的氮素状态有关。各处理土壤呼吸速率与土壤温度呈极显著指数正相关关系,对土壤呼吸与土壤温度和湿度的偏相关分析得出,温度能解释土壤呼吸的大部分变异（50.1%-79.8%）,是影响光皮桦林土壤呼吸的主导因子。随着氮沉降浓度的增加,土壤呼吸的Q10值减小,表明氮沉降可能降低了土壤呼吸的温度敏感性。展开更多
The seedling stage test on 55 open-pollinated families of plus trees of Betula luminifera H. Winkl. from Shaowu, Nanping and Wuping in Fujian Province was carried out in State-owned Forest Farm of Weimin, Shaowu. The ...The seedling stage test on 55 open-pollinated families of plus trees of Betula luminifera H. Winkl. from Shaowu, Nanping and Wuping in Fujian Province was carried out in State-owned Forest Farm of Weimin, Shaowu. The genetic variations of Betula luminifera were studied, based on the investigation of 1-year-old seedling traits from different families. The results showed that there were abundant variations within the Betula luminifera and very significant differences among families in seedling height, diameter and lateral branch. The variations were mainly controlled by genetic factors. According to this analysis, 11 excellent families were tentatively selected, the average genetic gain of height and diameter were 18.72% and 10.44% respectively. The selection effect was very striking. The Shaowu region was probably a superior genetic resource area of Betula luminifera .展开更多
The thousand\|seed weight,germination rate and vitality of seeds for \%Betula luminifera\% were studied.The results showed that the thousand\|seed weight was different in various habitats,and varied with the age and t...The thousand\|seed weight,germination rate and vitality of seeds for \%Betula luminifera\% were studied.The results showed that the thousand\|seed weight was different in various habitats,and varied with the age and the part of crown and fruit.The seed had a longevity of 32～37 days in general and with a characteristic of the rapid germination.The seed had a high germination rate during the early stage or perk stage of seed dispersal,and a lower germination rate during the end stage.The germination rate and vitality of mature seed reduced with the increase of the storing time,the change in seed germination was significantly different at the various ages and habitats.展开更多
文摘从2008年1月至12月,对华西雨屏区光皮桦（Betula luminifera）林进行了模拟氮沉降试验,应用LI-8100土壤碳通量分析系统和气压过程分离（Barometric Process Separation,BaPS）技术分别研究了4个氮沉降水平0（CK）、5（L）、15（M）、30（H）g N.m^-2.a^-1下土壤呼吸的日变化和月动态。结果表明,土壤呼吸具有明显的季节动态,各处理土壤呼吸最高值均出现在7月份;氮沉降初期,各处理土壤呼吸差异不明显,5月份以后各氮沉降处理土壤呼吸开始表现出抑制效应,随着施氮浓度的增加,抑制效应愈加明显（CK〉L〉M〉H）;土壤呼吸日变化基本呈现单峰曲线,呼吸速率最高值一般出现在14：00—16：00。随着氮沉降的增加,对土壤呼吸产生的抑制效应增强,这可能与光皮桦林土壤本身的氮素状态有关。各处理土壤呼吸速率与土壤温度呈极显著指数正相关关系,对土壤呼吸与土壤温度和湿度的偏相关分析得出,温度能解释土壤呼吸的大部分变异（50.1%-79.8%）,是影响光皮桦林土壤呼吸的主导因子。随着氮沉降浓度的增加,土壤呼吸的Q10值减小,表明氮沉降可能降低了土壤呼吸的温度敏感性。
文摘The seedling stage test on 55 open-pollinated families of plus trees of Betula luminifera H. Winkl. from Shaowu, Nanping and Wuping in Fujian Province was carried out in State-owned Forest Farm of Weimin, Shaowu. The genetic variations of Betula luminifera were studied, based on the investigation of 1-year-old seedling traits from different families. The results showed that there were abundant variations within the Betula luminifera and very significant differences among families in seedling height, diameter and lateral branch. The variations were mainly controlled by genetic factors. According to this analysis, 11 excellent families were tentatively selected, the average genetic gain of height and diameter were 18.72% and 10.44% respectively. The selection effect was very striking. The Shaowu region was probably a superior genetic resource area of Betula luminifera .
文摘The thousand\|seed weight,germination rate and vitality of seeds for \%Betula luminifera\% were studied.The results showed that the thousand\|seed weight was different in various habitats,and varied with the age and the part of crown and fruit.The seed had a longevity of 32～37 days in general and with a characteristic of the rapid germination.The seed had a high germination rate during the early stage or perk stage of seed dispersal,and a lower germination rate during the end stage.The germination rate and vitality of mature seed reduced with the increase of the storing time,the change in seed germination was significantly different at the various ages and habitats.
