Improving Systems Resilience and Productivity through Soil Mulching and Intercropping in Arid Areas.

In arid environments, crop production systems are highly vulnerable to environmental stresses such as drought. Information is lacking whether improved water conservation practices can be developed to enhance the systems resilience while maintaining or even increasing systems’ productivity. This project determined (i) the responses of soil evaporation and moisture conservation to the integrated straw/plastic (double mulching) system, (ii) the change of soil temperature during key plant growth stages under the integrated system, and (iii) the systems resilience and productivity in response to conservation practices. Experiments were carried out in northwest China from 2009 to 2011. Plastic film and straw mulching were integrated in intensified strip intercropping. Wheat-maize strip intercropping in combination with plastic film and straw covering on the soil surface increased soil moisture by 3.8 % before sowing, 5.3 % during the wheat and maize co-growth period, 4.4 % after wheat harvest, and 4.9 % after maize harvest, compared to conventional practice (control). The double mulching increased soil temperature of maize strips by 1.25 to 1.94 °C than that of wheat strips in the top 10-cm soil depth. Also, straw mulching increased the secondary super-compensation effect of intercropped maize by 11 to 26% from leaf, stem and sheath of maize, which contributed an increased yield of 14 to 33%, compared to the maize in the other treatments. As a result, the intercropping with mulching increased total grain yield by 74% and harvest index by 12%, compared with the conventional control treatment. We concluded that intercropping wheat and maize with straw mulching on the soil surface can serve as an effective soil management approach to improve the systems resilience and productivity in arid areas.