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Effects of fire disturbance on the forest structure and succession in the natural broad-leaved/Korean pine forest

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Journal of Forestry Research 2003年第4期14卷 269-274页

作者：刘丽娟葛建平北京师范大学

Investigations on charcoal in the soil, fire-scarred trees, stand composition, forest structure as well as regeneration status were carried out in the natural broad-leaved/Korean pine (Pinus koraiensis) forest after fire disturbance at Liangshui Nature Reserve on the mid-north of Xiaoxingan Mountains from 1990 to 1992, and the ecological effects of fire disturbance on the formation and succession of this kind of forest were analyzed according to the survey results. The average depth of charcoal in the soil was related to the timing of the fire. According to the characteristic of fire-scarred trees, the dynamic map of the fire behavior was drawn onto the topographic map. It showed that the dimension and extent of the fire disturbance was closely related with site conditions. fire disturbance only led to a significant difference in stand composition and diameter class structure for the stands at different locations, rather than completely destroying the forest. After fire disturbance, the horizontal community structure was a mosaic of different patches, which were made up of different deciduous species or different sizes of Korean pines, and the succession trend of each patch was also different. In the sites with the heavy fire disturbance, the intolerant hardwood species were dominant, and there were a large number of regenerative Korean pine saplings under the canopy. In the moderate -disturbed sites, the tolerant hardwood species were dominant, and a small number of large size Korean pines still survived. In the light-disturbed sites, large size Korean pines were dominant.

关键词： Pinus koraiensis Natural forest fire disturbance Succession

Decay rate of Larix gmelinii coarse woody debris on burned patches in the Greater Khingan Mountains

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Journal of Forestry Research 2021年第6期32卷 2349-2363页

作者： Shubo Huang Lixiang Wen Shuai Yin Meng Guo Fangbing Yu Key Laboratory of Geographical Processes and Ecological Security in Changbai Mountains School of Geographical SciencesNortheast Normal UniversityMinistry of EducationChangchun130024People’s Republic of China Center for Global Environmental Research National Institute for Environmental StudiesTsukuba3058506Japan

The decomposition of coarse woody debris(CWD)affects the energy flow and nutrient cycling in forest *** studies on CWD have focused on the input,decomposition,reserve dynamics,and CWD functions,but coarse woody debris decomposition is complex and the results from different regions vary *** is not clear which factors affect decay rate(k),especially at different decomposition *** this study,a single-exponential decay model was used to analyze the characteristics of CWD decomposition in Larix gmelinii forests over the 33 years following a fire in the Greater Khingan *** results show that the decay rate of coarse woody debris was positively correlated to decay *** average decomposition rate was 0.019,and 41 years and 176 years are needed for a 50%and 95%mass loss,*** nutrient content,density,and water content could explain the variance in the decay rate(~42%)of the decay factors such as amount of leaching,degree of fragmentation,respiration of the debris,and biotransformation,and varied significantly between different decay *** the space-time substitution method,this study arranged the coarse woody debris of different mortality times to form a 33 year chronosequence which revealed the decomposition *** was concluded that the decay rate was mainly explained by structural component of the debris and its nitrogen and water *** paper quantifies the indicators affecting CWD decay to explain the decomposition process.

关键词： Coarse woody debris Decay rate Space–time substitution Boreal forest fire disturbance

Effects of Spatial Aggregation on Forest Landscape Model Simulation in Northeastern China

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Transactions of Tianjin University 2009年第3期15卷 178-186页

作者：周宇飞贺红士布仁仓金龙如李秀珍 Institute of Applied Ecology Chinese Academy of Sciences Graduate School of Chinese Academy of Sciences School of Natural Resources University of Missouri-Columbia

Issues of scale and aggregation become important when large range of space and time scales is considered in landscape ***,identifying appropriate levels of aggregation to accurately represent the processes and components of ecological systems is challenging.A raster-based spatially explicit forest landscape model,LANDIS,was used to study the effects of spatial aggregation on simulated spatial pattern and ecological process in Youhao Forest Bureau of the Small Khingan Mountain in Northeastern *** model was tested over 500 simulation years with systematically increased levels of spatial *** results show that spatial aggregation significantly influences the simulation of fire disturbance,species abundance,and spatial *** fire regime was relatively insensitive to grain size between 30.m and 270.m in the *** aggregation from 300.m to 480.m dramatically decreased fire return interval(FRI) and increased mean fire ***,species abundance and its aggregation index(AI) remained higher level over simulation years at the fine-grained level of spatial aggregation than at coarser *** addition,the simulated forest dynamics was more realistic at finer *** results suggest that appropriate levels of spatial aggregation for the model should not be larger than 270m.

关键词： scale spatial aggregation LANDIS fire disturbance succession spatial pattern Northeastern China