Yunxin HUANG, Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences, China
Yansui LIU, Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences, China
Zhengjia LIU, Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences, China
Yurui LI, Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences, China
Enhancing the quality of croplands in land consolidation projects can improve land use efficiency and boost agricultural production. About 33,333.3 ha of land were reclaimed in an engineering effort named Gully Land Consolidation Project to supplement cropland in Yan’an, Loess Plateau, China. However, the quality of some newly-constructed cultivated lands was poor, hindering their efficient utilization. To overcome this problem, red clay and Malan loess were compounded in different volume ratios to explore improvements in the engineering of constructing productive farmland. The Root Zone Water Quality Model was used to simulate the effects of different soil treatments on soil water, nitrogen and maize growth. Experimental data were collected from 2018 to 2019 to calibrate and validate the model. Experiment showed that, compared with land constructed with Malan loess only (T1), the soil structure and hydraulic characteristics of land with a volume ratio of red clay and Malan loess of 2:1 (T3) was better. Simulation indicated that, compared with T1, the soil water content and available water content of T3 increased by 14.4% and 19.0%, respectively, while N leaching decreased by 16.9%. The aboveground biomass and maize yield of T3 were 7.9% and 6.7% higher than that of T1, respectively. Furthermore, the water productivity and nitrogen use efficiency of T3 increased by 21.0% and 16.6% compared with that of T1. This study documented that compounding red clay and Malan loess in an appropriate ratio could greatly improve soil structure, soil water and nutrient retention capacity, achieving higher yields, smaller environmental costs and optimize the utilization efficiency of water and nitrogen. These findings can guide the engineering or improvement of farmland in similar land consolidation projects.
Mots clés : Soil reconstruction|Soil quality| Soil structure| Soil water and nitrogen|RZWQM2
A104096YH