A Closer View of Smallholder Agriculture in Congo Basin Forests: Use of High Resolution Imagery to Quantify Spatial Relationships of Agriculture with Roads and Land Management after Recent Intensification of Commercial Logging Operations

Congo Basin tropical forest;Spatial interaction between roads and agriculture;Forestry laws and zoning practices;Spatial anaysis and modeling;Remote sensing: very high resolution imagery;Natural Resources and Environment;Science (General);Statistics and Numeric Data;Science;Natural Resources and Environment

Cordero-Sancho, SilviaIbanez, Ines ;

University of Michigan

关键词: Congo Basin tropical forest;    Spatial interaction between roads and agriculture;    Forestry laws and zoning practices;    Spatial anaysis and modeling;    Remote sensing: very high resolution imagery;    Natural Resources and Environment;    Science (General);    Statistics and Numeric Data;    Science;    Natural Resources and Environment;   

Others  :  https://deepblue.lib.umich.edu/bitstream/handle/2027.42/137161/corderos_1.pdf?sequence=1&isAllowed=y

瑞士|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

In the Congo Basin, changes in forest policy promoted the development of commercial timber activities and defined different forest-use zones. Timber activities have extended the road presence in the Basin, while zoning has attempted to control where anthropogenic activities are occurring, including smallholder agriculture, an activity considered as one of the main causes of deforestation in the Basin. Therefore, the main concern of the lengthening of the road network is that it could support the development of agriculture. Relationships between roads and agriculture has been studies in other tropical regions, however little work has been conducted in the Basin under the current policies. This study aimed to evaluate the spatial relationships between agriculture, roads, and current land-zoning practices. To do so, twenty-six very-high resolution images, within seven case study sites within Cameroon and the Republic of the Congo were employed to map and characterize agriculture at its smallest size, roads and other anthropogenic activities.Results of multiple analyses indicated that, considering the dominance of small plots (64% <1-ha) agricultural clearings presented characteristics associated with smallholder agriculture.Distance relationships between agriculture and roads indicated that 60% of all clearing occurred near (<1-km) roads, but not all roads were in proximity to agriculture, in special, clearings were more likely to occur near maintained roads: 53% of all clearing were <1-km to a maintained road while only 8% were <1-km to unmaintained roads.Further, Gibbs spatial point pattern modeling methods indicated that that nearness to roads influenced the incidence of agriculture when the following conditions were present: 1) presence of active logging, 2) dominance of maintained roads, and 3) nearness to large towns. Forest-use zoning analysis indicated that most clearings occurred within agricultural friendly zones (non-permanent forest in Cameroon and community development series in Congo) but also clearings occurred within the permanent forest zones (production forest in Cameroon and Congo).In Cameroon, 99% of the clearings within the production forest (n=148) occurred < 3 km from a road, while in Congo, 64% of the clearings within production forest (n=443) occurred at the same distance range; however, analysis suggested that some of the clearings within the production forest could be associated to transient agriculture conducted by logging workers. Results updated the understanding of agriculture and roads in the Basin, while emphasize the need for further research and resources to integrate agricultural activities as part of the conservation efforts while guaranteeing food security and improving local peoples’ livelihoods.