Improving fertility and productivity of a highly-weathered upland soil in subtropical China by incorporating rice straw

Abstract

The transfer of rice straw from paddy fields to upland areas was proposed in our study as an innovative practice to improve the fertility of the highly-weathered and poor upland soils, as well as to mitigate environmental impacts from rice production system (e.g., the large application of chemical fertilizers, straw burning, CH 4 emission from decomposed straw) in the subtropical China. Data from an 8-year field experiment with sweet potato and rapeseed show that, the contents of organic matter and total nitrogen (N) in the surface soil (0-20 cm) with rice straw incorporation were increased by 13%, and the amounts of soil microbial biomass carbon (C), N, and phosphorus (P) by 18-43%, compared with the values when chemical fertilizers (NPK) were applied alone. Physical conditions and crop productivity of the test soil were effectively promoted with the straw incorporation, as indicated in significant changes in soil field water-holding capacity, total porosity, and bulk density in the 10-15 cm soil layer, and the rise (about 10% and 20%, respectively) of sweet potato and rapeseed yields. In conclusion, these results suggest that the practice shift from conventional rice straw management ('on the spot' incorporation) to upland incorporation is effective in improvement in fertility and productivity of the upland soil, which has potentials to reduce the amounts of chemical fertilizers applied and to increase soil C storage in farmlands in the region.

Effects of straw incorporation on the stratification of the soil organic C, total N and C:N ratio in a semiarid region of China

“…In our study, the crop biomass and grain yields were higher with straw incorporation than conventional tillage (NA). Similar effects were reported by Zhu et al (2010) based on an 8-year field experiment in China. Note: RP, before treatment; NA, no straw incorporation; LA, incorporation of straw at a low rate of 4.5 Mg ha À1 yr À1 maize straw; MA, incorporation of straw at a medium rate of 9.0 Mg ha À1 yr À1 maize straw; HA, incorporation of straw at a high rate of 13.5 Mg ha À1 yr À1 maize straw.…”

Phosphorus status and its sorption-associated soil properties in a paddy soil as affected by organic amendments

“…No significant difference in soil P accumulation was observed when compared between straw and MF treatments, probably because P content in straw was relatively lower compared with the P in manure. Zhu et al (2010) also reported that, in an 8-year field experiment, chemical fertilizers plus straw incorporation did not significantly increase soil TP and Olsen-P contents in subtropical region of China compared with chemical fertilizer application. Phosphorus accumulation in soil under a certain fertilization treatment or P budget usually exhibited a linear correlation with management history (Whalen and Chang 2001;Messiga et al 2010;Ciampitti et al 2011).…”

“…Organic amendments, such as application of manure and compost, and the incorporation of crop residues are effective methods to improve soil fertility and productivity (Zhu et al 2010). Recently, the incorporation of crop residues to the soil is highly advocated in China, since the burning of residues in situ by farmers, as usually did, is causing a serious waste of nutrient resources besides contributing to air pollution.…”

Effects of Hyperaccumulator Straw on Soil Nutrient Availability and Soil Enzyme Activity of Cyphomandra betacea under Cadmium Stress

“…Cadmium (Cd) is one of heavy metal that is not biodegradable and considered to be a very hazardous element to environment [2]. Mulching with plant straw on soil surface is one of the natural methods using in agricultural production, and straw mulch decomposes in the soil and converts into organic matter, allelopathic substances and other nutrients, which can fertilize the soil, improve soil texture and affect physiological and biochemical activities of soil microorganisms [3][4]. If we apply the plant straw in heavy metal contaminated soil, the plant straw could affect the heavy metal bioavailability, and decrease or increase the heavy metal absorption of living plant [5].…”