Categorized analysis of forest ecological values in the China’s conversion cropland to forest program

Background\n\nThe Chinas Conversion Cropland to Forest Program (CCFP) is one of the large state ecological construction programs. Up to now, the program has effectively improved the ecological environment and produced large ecological benefit. However, there were also some problems in its implementation process, the program has been sometimes less effective than the expected.\n\nMethods\n\nBased on the data and the methods of State report on monitoring ecological effects in CCFP and the Chinese Forest Ecosystem Research Network (CFERN) in 2013, we analyzed the categorized forest ecological benefit value (B-V) s in the three forest restoration ways in different regions in China to provide references for CCFP construction.\n\nResults\n\nThe unit area B-Vs in CCFP varied between 35 000 RMBs.hm-2.a-1 and 100 000 RMBs.hm-2.a-1. Water conservation B-V and species conservation B-V were the two largest constituents, nutrient accumulation B-V was the least in all the categorized B-Vs on regional and unit area scale. The rank of restoration ways on average unit area total B-Vs was-- hillside forest conservation > returning cropland to forest > afforestation on suitable barren hills and wasteland in CCFP. Among the categorized B-Vs, some pairs were positively correlated with each other and some were negatively correlative. The correlation coefficients and some regression equations were given in the text and the attached Fig.s.\n\nConclusions\n\nWater conservation B-V was the highest and nutrient accumulation B-V was the lowest whether on regional or unit area scale in CCFP.\n\nForest ecological B-Vs varied in different forest restoration ways and different regions in CCFP. The hillside forest conservation restoration way and the water conservation B-V should be paid more attention in Chinas future forest restoration. We suggest that suitable forest restoration ways should be selective according to the regional specific and ecological targets.\n\nThere were correlations among the categorized B-Vs, and the correlations varied with different forest restoration ways in CCFP. Knowing about the correlations could clarify the targeted restoration ways according to the goal of ecological benefit.