Soil C and N dynamics and hydrological processes in a maize-wheat rotation field subjected to different tillage and straw management practices

Li Wang; Xiaoliang Yuan; Chuang Liu; Zhiguo Li; Fang Chen; Shiqing Li; Lianhai Wu; Yi Liu

doi:10.1016/j.agee.2019.106616

Soil C and N dynamics and hydrological processes in a maize-wheat rotation field subjected to different tillage and straw management practices

Agric Ecosyst Environ. 2019 Dec 1:285:106616. doi: 10.1016/j.agee.2019.106616.

Authors

Li Wang^{1

2}, Xiaoliang Yuan¹, Chuang Liu¹, Zhiguo Li^{1

2}, Fang Chen^{1

2}, Shiqing Li³, Lianhai Wu⁴, Yi Liu^{1

2

3}

Affiliations

¹ Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074, China.
² Center of Conservation Biology/Economic Botany/Plant Ecology, Core Botanical Gardens, Chinese Academy of Sciences, Wuhan 430074, China.
³ State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resource, Yangling 712100, China.
⁴ Sustainable Agricultural Sciences, Rothamsted Research, North Wyke, Okehampton EX20 2SB, UK.

Abstract

The impact of farmland nutrient losses on environment security is of serious concern. Conservation tillage led to reduced water and soil losses and increased grain yield, and is therefore one potential solution, but this approach requires an understanding of the complex adaptive traits for environment conditions. In this study, a 4-year field experiment was conducted to quantify the crop yield, runoff and soil water, organic C and N content dynamics in summer maize-winter wheat rations subjected to different tillage and straw management practices. Based on these, the effects of different tillage and straw management regimes on water, C and N balances of the soil-plant system was evaluated with a 11-year model prediction using the SPACSYS model. The treatments used in this study included conventional tillage (CT) with straw removal, conventional tillage with straw returning (CTSR), reduced tillage (RT) with straw removal and reduced tillage with straw returning (RTSR). The results showed that maize yield was remarkably affected by straw returning while there was no significant tillage effect. By contrast, wheat yield showed a high inter-annual variability, but was not significantly influenced by tillage and straw management practices. The soil water balance analysis demonstrated that the treatments with straw returning improved water use efficiency by increasing transpiration while reducing water losses through evaporation and runoff, compared to the straw-removal treatments. The simulations for all of the treatments showed that the soils acted as C and N sinks in the present study. Furthermore, plots that included straw returning amassed more C and N in the soil than the that with straw removal. Our work demonstrates that in maize-wheat rotation slopping land reduced tillage with straw returning is a win-win practice for the equilibrium between agricultural productivity and low soil water, C and N losses.

Keywords: Conservation tillage; Danjiangkou Reservoir; SPACSYS; Soil C and N balances; Surface runoff.

Grants and funding

BBS/E/C/000I0320/BB_/Biotechnology and Biological Sciences Research Council/United Kingdom