| China’s recent rapid economic development has resulted in a prominent problem of continuous reduction in both cropland area and production. To address this issue, the Chinese central government made a series of policies to protect cropland. One of the most important measures is land consolidation in order to protect cropland, improve land quality, and increase agricultural productivity and resilience. Therefore, land consolidation is regarded as an important way to maintain food security and is highly valued by the Chinese government. For example,11.7×104 land consolidation projects have been implemented during 2006-2010, which led to 5.62×106 hm2 cropland has been renovated and 2.O×106 hm2 cropland has been newly added.However, no formal evaluation of productivity has been conducted on these projects. Although the quantity of new cropland added after land consolidation can be accurately measured, it is difficult to assess the influence of land consolidation on the actual production capacity because grain production is affected by many factors, such as climate and agricultural management. This study is the first-ever to measure the effectiveness of China’s land consolidation policy in improving agricultural productivity. Previous studies have shown that there is a strong positive correlation between normalized difference vegetation index (NDVI) and crop yields. We thus eliminated the influence of climate change and agricultural management measures as much as possible by using control sites in the area closely surrounding the project areas. By assuming that the agricultural managements of project and control sites are the same, we compared the NDVI changes between project and control sites before and after the consolidation to evaluate whether productivity has been improved, moreover, cropland consolidation projects implemented during 2006-2010 have been evaluated. Finally, the Logit regression model was used to analyze potential factors which could affect the effectiveness of land consolidation in different periods in the Country and typical provinces. The major conclusions are listed as follows:(1) Propose the mechanisms and ways of the influence of land consolidation on cropland productivity. Land consolidation can change the quantity and quality of cropland area by many engineering approaches including land leveling, irrigation and drainage engineering to improve productivity.(2) Establish methods and models of evaluating the impact of land consolidation on cropland productivity based on NDVI parameters. We applied the NDVI to represent real land productivity, set up a reference area around each project area, eliminate the interference of factors such as climate change through a real-time comparison of a pair of reference and project areas, and built an evaluation model from the perspectives of productivity increment and stability in order to assess the impact of land consolidation on real productivity in project areas.(3) Use the MODIS images from 2001 to 2013 and national cropland consolidation data from 2006 to 2010, obtain NDVI data through a series of spatial analysis, and study the impact of land consolidation on real cropland productivity based on the established evaluation model. Mabout 60% of projects have achieved the objects of increasing cropland productivity after consolidation during 2006-2010, and the proportion of effective projects showed an increase trend. There was regional difference of effective parcels. For example, there are three hotspots of the effective parcels distributed in Shandong, centre of Jilin, and east of Hunan, respectively. Meanwhile, there are also several coldspots of the non-effective parcels distributed in Zhjiang, Heilongjiang, and Gansu, respectively. The productivity of about 50% of projects became more stable after consolidation. There are several hotspots of the effective parcels distributed in west of Jilin, Zhejiang, east of Hunan, respectively. Generally spreaking, most of the projects showed effective at improving or stabilizing agricultural productivity, and the proportion of effective parcels displayed an increased trend. However, less than half of projects can not only increase productivity but also be stable.(4) The regression models show that the effectiveness of consolidation is affected by different factors in different periods in different regions. Generally, the average annual temperature, the average annual sunshine, agriculture water consumption, water and soil matching coefficient, GDP, construction area and the rate of newly added cropland have positive influences on the effectiveness of land consolidation, while non-effective projects more likely located in areas with a high value of altitude, slope, population density, and irregular shapes.
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