Analysis Of Temporal And Spatial Changes And Their Driving Force In Forest Resources Of Typical Ecological Restoration Counties Of Three Gorges Reservoir Region Over The Past Decade

High-resolution SPOT-5images were used as basic data sources and based ontopographic maps, maps of the second national land survey, site investigation, etc.high-resolution SPOT-5(2.5m) remote sensing images were visually interpreted toobtain subcompartment division, and then survey by subcompartment was conductedto get the2011woodland status map; on this basis, combined with the2002surveymap the spatial distribution pattern of woodland over a decade was obtained, and thena correlation model was used to analyze the time-varying characteristics of the samplewoodland area, while Ripley K function was used to have a deeper grasp of changes inspatial scales; the driving force of these changes was also analyzed from perspectivesof policies and regulations, natural factors, socio-economic factors and so on. Thestudy showed the following results.Visual interpretation of panchromatic images using312-band combinations couldreflect the land class information to the maximum, and the average field validation andinterpretation accuracy reached93.27%. The sample area is rich in forest resources,where the woodland area was176971.11ha in2002and207716.99ha in2011. Fangdou–Qiyao Mountains concentrate different types of woodland, while there are relativelyfew troughs and flatlands. Arbor woodland had obvious substrate advantages in thetwo years of survey.In terms of temporal changes, the woodland showed large quantitative changes in2002-2011, when the general trend was that the forest area was increasing, resulting inan increase of30745.88ha over a decade; however, incremental degree and amount ofdifferent types of woodland was not the same due to differences in basal values, wherearbor woodland showed the largest change in area (37921.29ha), followed by shrubwoodland (-5023.87ha); in terms of spatial patterns, overall the woodland showedaggregated distribution, but the intensity of concentration varied with sporadic patches scattered therein. Conversion of forestland was based on conversion of shrubbery andimmature forestland into arbor woodland.Dynamic changes in woodland not only benefit from the remarkable success of suchpolicy measures as conversion of farmland to forests (12220.12ha), Chongqing ForestEngineering (4627.89ha), forests protection to promote construction, and so on; butwoodland distribution at different terrain niches and different buffer radii around roadsand settlements are also mainly driven by stress of human activities in the sample areadominated by large topographical patterns characterized by mountains: in areas withlower terrain niche index, the density of distribution of roads and settlements is higherthan areas with higher terrain niche index, so anthropogenic disturbance greatlyreduces, combined with that in areas with more woodland distribution, woodland itselfhas a certain barrier effect on human activities in mountainous areas, resulting inincrease in the buffer radius and increasing forest surrounding the roads andsettlements; also component factors of socio-economy in the same area are correlated:the total income of the regional economy, forestry output value and forest plantationarea are the main driving factors affecting the distribution of forestland. The resultshelp enrich people’s in-depth knowledge on woodland pattern of key ecologicalrestoration areas, thereby providing a scientific underlying data basis for the effectiveutilization of woodland.