Mapping Forest Cover in Northeast China from Chinese HJ-1 Satellite Data Using an Object-Based Algorithm  
[PERSON]  
1 Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China; [EMAIL_ADDRESS] (C.R. ); [EMAIL_ADDRESS] (Z.W. ); [EMAIL_ADDRESS] (M.J.)  
[PERSON]  
1 Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China; [EMAIL_ADDRESS] (C.R. ); [EMAIL_ADDRESS] (Z.W. ); [EMAIL_ADDRESS] (M.J.)  
[PERSON]  
1 Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China; [EMAIL_ADDRESS] (C.R. ); [EMAIL_ADDRESS] (Z.W. ); [EMAIL_ADDRESS] (M.J.)  
[PERSON]  
1 Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China; [EMAIL_ADDRESS] (C.R. ); [EMAIL_ADDRESS] (Z.W. ); [EMAIL_ADDRESS] (M.J.)  
[PERSON]  
1 Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China; [EMAIL_ADDRESS] (C.R. ); [EMAIL_ADDRESS] (Z.W. ); [EMAIL_ADDRESS] (M.J.)  
Il36 iuppui.edu  
1 Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences, Changchun 130102, China; [EMAIL_ADDRESS] (C.R. ); [EMAIL_ADDRESS] (Z.W. ); [EMAIL_ADDRESS] (M.J.)  
2 Department of Earth Sciences, Indiana University-Purdue University, Indianapolis, IN 46202, USA; l136 iuppui.edu  
26 November  
Northeast China harbors the largest relatively contiguous area of forested land in contemporary China [6], which is composed of different types of forest, including evergreen needleleaf forest, deciduous needleleaf forest, deciduous broadleaf forest, and mixed forest [7]. This region has experienced dramatic deforestation due to agricultural activities, urbanization, and water project constructions [8; 9]. According to the national survey of forest resources, the area of mature forest contracted 49.0% in the period 1981-1988; then, in the following 10 years (1988-1998), 0.61 million ha of forest area further disappeared, accounting for approximately 60.0% of the entire country's total mature forest area [5]. According to the 6 th National Continuous Forest Inventory in 2003, the forested area of Northeast China increased by 12.2 million ha compared to the forested area in 1950. In the forest provinces of Northeast China, the declined forest was almost entirely restored during this same period [10]. Northeast China is a pilot region for the Grain for Green Project, the Logging Ban Project, and other ecological restoration projects that have, to some extent, been successful in meeting their objectives [11; 12]. However, the forest-contracting trend still exists [13; 14]. The lack of readily accessible, peer-reviewed data sources results in the statistics on forest cover in Northeast China cited by scientific publications that varied widely. Additionally, the reliability of forest trend data analysis is uncertain due to inconsistencies among study periods or the use of different data sources by researchers. It is essential for government managers and researchers to obtain accurate and updated information on forest areas and variation at the regional scale. Remote sensing has significantly contributed to the detection of forest extent, types, and changes at regional and global scales [15; 16]. A number of earlier studies mapped forest in Northeast China using remote sensing data, including the NOAA/AVHRR data [17], SPOT-4 VEGETATION composite data [5] and MODIS datasets [18; 19].