Charcoal production through selective logging leads to degradation of dry woodlands:a case study from Mutomo District,Kenya  

作　　者：Geoffrey M NDEGWA Udo NEHREN Friederike GRüNINGER Miyuki IIYAMA Dieter ANHUF 

机构地区：[1]Department of Physical Geography,University of Passau,Passau 40,94036,Germany [2]Institute for Technology and Resources Management in the Tropics and Subtropics,TH Ko1n University of Applied Sciences,Cologne 2,50679,Germany [3]The World Agroforestry Centre,Nairobi 30677-00100,Kenya [4]The Japan I-nternational Research Center for Agricultural Sciences(JIRCAS)1-1 Owashi,Tsukuba,lbaraki Prefecture 305-0851,Japan

出　　处：《Journal of Arid Land》2016年第4期618-631,共14页干旱区科学（英文版）

基　　金：the financial assistance accorded by the World Agroforestry Center(ICRAF)and the Center for Natural Resources and Development(CNRD)of TH Koln University of Applied Sciences without which this study would not have been possible

摘　　要：Provision of woodfuel is an important ecosystem service of dry forests and woodlands. However, charcoal production through selective logging of preferred hardwood species has the potential to alter the physiognomic composition of the residual or re-growth woodlands and may lead to their deterioration and degradation. This study, conducted through forest inventory in Mutomo District in Kenya, assessed the impact of charcoal production on unprotected dry woodlands in terms of tree density, targeted species basal area, species richness, evenness and Shannon diversity. The parameters of the disturbed woodlands were evaluated for significant differences with those of the neighbouring protected Tsavo East National Park, which served as a reference for an ecologically undisturbed ecosystem. By evaluating a consequence of tree harvesting for charcoal production, this study confirmed the overall significant differences between the protected and unprotected woodlands in all the tested parameters. To confirm if the differences in the land-covers of the woodlands had any influence on their degradation, all mentioned parameters were compared between the four differentiated classes and their respective control plots in the protected areas. At the ＂land-cover level＂, the statistically significant difference in the basal area of tree species preferred for charcoal production between the protected and unprotected open trees confirms that the class with a high density of large mature trees is the prime target of charcoal producers. In addition, there seems to be a general trend of lower values of tree species richness, evenness and Shannon diversity for the unprotected woodlands subjected to charcoal production. On the other hand, the disturbed woodlands display the potential to recover through their comparably high saplings density. The findings make an important contribution to the discourse on the impact of charcoal production in dry woodlands, a topic that is highly controversial among researchers.Provision of woodfuel is an important ecosystem service of dry forests and woodlands. However, charcoal production through selective logging of preferred hardwood species has the potential to alter the physiognomic composition of the residual or re-growth woodlands and may lead to their deterioration and degradation. This study, conducted through forest inventory in Mutomo District in Kenya, assessed the impact of charcoal production on unprotected dry woodlands in terms of tree density, targeted species basal area, species richness, evenness and Shannon diversity. The parameters of the disturbed woodlands were evaluated for significant differences with those of the neighbouring protected Tsavo East National Park, which served as a reference for an ecologically undisturbed ecosystem. By evaluating a consequence of tree harvesting for charcoal production, this study confirmed the overall significant differences between the protected and unprotected woodlands in all the tested parameters. To confirm if the differences in the land-covers of the woodlands had any influence on their degradation, all mentioned parameters were compared between the four differentiated classes and their respective control plots in the protected areas. At the ＂land-cover level＂, the statistically significant difference in the basal area of tree species preferred for charcoal production between the protected and unprotected open trees confirms that the class with a high density of large mature trees is the prime target of charcoal producers. In addition, there seems to be a general trend of lower values of tree species richness, evenness and Shannon diversity for the unprotected woodlands subjected to charcoal production. On the other hand, the disturbed woodlands display the potential to recover through their comparably high saplings density. The findings make an important contribution to the discourse on the impact of charcoal production in dry woodlands, a topic that is highly controversial among researchers.

关 键 词：charcoal burning forest degradation selective harvesting Acacia-Commiphora bushland COPPICING 

分 类 号：S750[农业科学—森林经理学]