In order to identify a harvesting model which is beneficial for broadleaf-Korean pine mixed forest （BKF） sustainability, we investigated four types of harvested stands which have been logged with intensities of 0 （...In order to identify a harvesting model which is beneficial for broadleaf-Korean pine mixed forest （BKF） sustainability, we investigated four types of harvested stands which have been logged with intensities of 0 （T0, control）, 15% （T1, low intensity）, 35% （T2, moderate intensity）, and 100% （T3, clear-cutting）, and examined the impacts of logging intensity on composition and structure of these stands. Results showed that there were no significant differences between To and T1 for all structural characteristics, except for density of seeding and large trees. The mean diameter at breast height （DBH, 1.3 m above the ground）, stem density and basal area of large trees in T2 were significantly lower than in To, while the density of seedlings and saplings were significantly higher in T2 than in To. Structural characteristics in T3 were entirely different from To. Dominant tree species in primary BKF comprised 93%, 85%, 45% and 10% of the total basal area in T0, T1, T2 and T3, respectively. Three community similarity indices, the Jaccard＇s similarity coefficient （Cj）; the Morisita-Hom index （CMH）; and the Bray-Curtis index （CN）, were the highest for T0 and T1, followed by T0 and T2, and T0 and T3, in generally. These results suggest that effects of harvesting on forest composition and structure are related to logging intensities. Low intensity harvesting is conductive to preserving forest structure and composition, allowing it to recover in a short time period. The regime characterized by low logging intensity and short rotations appears to be a sustainable harvesting method for BKF on the Changbai Mountains.展开更多
PnET-Ⅱ(photosynthesis and evapotranspiration)模型是生态系统过程模型,运行过程中所需的参数较多,包括植被、土壤和气候参数等.本文估计了丰林自然保护区阔叶红松林中红松和阔叶树的总净初级生产力(NPP)和枝干NPP对PnET-Ⅱ模型参数...PnET-Ⅱ(photosynthesis and evapotranspiration)模型是生态系统过程模型,运行过程中所需的参数较多,包括植被、土壤和气候参数等.本文估计了丰林自然保护区阔叶红松林中红松和阔叶树的总净初级生产力(NPP)和枝干NPP对PnET-Ⅱ模型参数变化的敏感程度.结果表明:PnET-Ⅱ模型的植被参数中,林冠参数变化对模拟结果影响较大,且红松总NPP对植被参数的敏感性大于阔叶树;红松和阔叶树NPP对土壤持水量变化敏感性较小,且红松NPP对土壤持水量的敏感性略小于阔叶树;在气候情景范围内,气温变化对红松和阔叶树NPP的影响最大,降水和光合有效辐射次之.不同气候情景对NPP模拟结果的影响不同.红松和阔叶树的总NPP和枝干NPP对各输入参数的敏感程度并不完全一致.展开更多
基金National Key Technologies Research and Development Program of China(No.2012BAD22B04)
文摘In order to identify a harvesting model which is beneficial for broadleaf-Korean pine mixed forest （BKF） sustainability, we investigated four types of harvested stands which have been logged with intensities of 0 （T0, control）, 15% （T1, low intensity）, 35% （T2, moderate intensity）, and 100% （T3, clear-cutting）, and examined the impacts of logging intensity on composition and structure of these stands. Results showed that there were no significant differences between To and T1 for all structural characteristics, except for density of seeding and large trees. The mean diameter at breast height （DBH, 1.3 m above the ground）, stem density and basal area of large trees in T2 were significantly lower than in To, while the density of seedlings and saplings were significantly higher in T2 than in To. Structural characteristics in T3 were entirely different from To. Dominant tree species in primary BKF comprised 93%, 85%, 45% and 10% of the total basal area in T0, T1, T2 and T3, respectively. Three community similarity indices, the Jaccard＇s similarity coefficient （Cj）; the Morisita-Hom index （CMH）; and the Bray-Curtis index （CN）, were the highest for T0 and T1, followed by T0 and T2, and T0 and T3, in generally. These results suggest that effects of harvesting on forest composition and structure are related to logging intensities. Low intensity harvesting is conductive to preserving forest structure and composition, allowing it to recover in a short time period. The regime characterized by low logging intensity and short rotations appears to be a sustainable harvesting method for BKF on the Changbai Mountains.
文摘PnET-Ⅱ(photosynthesis and evapotranspiration)模型是生态系统过程模型,运行过程中所需的参数较多,包括植被、土壤和气候参数等.本文估计了丰林自然保护区阔叶红松林中红松和阔叶树的总净初级生产力(NPP)和枝干NPP对PnET-Ⅱ模型参数变化的敏感程度.结果表明:PnET-Ⅱ模型的植被参数中,林冠参数变化对模拟结果影响较大,且红松总NPP对植被参数的敏感性大于阔叶树;红松和阔叶树NPP对土壤持水量变化敏感性较小,且红松NPP对土壤持水量的敏感性略小于阔叶树;在气候情景范围内,气温变化对红松和阔叶树NPP的影响最大,降水和光合有效辐射次之.不同气候情景对NPP模拟结果的影响不同.红松和阔叶树的总NPP和枝干NPP对各输入参数的敏感程度并不完全一致.
