Effects of Soil Aggregates Composition and Distribution Using Food Waste Soil Conditioner in the Orchard Soil

Abstract

The increase in population and food demand poses challenges to agriculture and the excessive use of chemical fertilizer has led to the deterioration of soil functions in China.The green and sustainable development of agriculture is seriously affected due to the impoverished organic-matter and structural damages of the orchard soil.In this study,the effects of long-term application of food waste soil conditioner on the characteristics of soil aggregates and the generation and transformation of organic matter in barren orchards were carried out from the perspective of time and space.The proportion of soil granular structure(DR 0.25),mean weight diameter(MWD),geometric mean diameter(GMD)and fractal dimensions of soil aggregates were investigated using food waste soil conditioner in the orchard soil.The results showed that under the application of food waste soil conditioner,microaggregates(<0.25 mm)in the surface soil of 0-20 cm increased,and the maximum value of proportion of water-stable aggregates(W w i)reached 23.04%after 3 years of the food waste soil conditioner application.Therefore,food waste soil conditioner application had the potential to improve the soil erosion resistance.With the long-term application of food waste soil conditioner,the DR 0.25 in 30-40 cm deep soil increased with time.The MWD and GMD were better than the blank group after 5 years of application the food waste soil conditioner.With the long-term application of food waste soil conditioner,the fractal dimensions decreased in 0-20 cm surface soil.Then,the minimum value of fractal dimensions was 2.13 after 5 years of treatment.These changes indicated that food waste soil conditioner application was conducive to improving the soil aggregate particle size distribution and the fractal features.Under the food waste soil conditioner application,the content of organic matter in 0.5-5 mm aggregates increased.Overall,the results showed that long-term application of food waste soil conditioner improved the particle size and organic matter distribution in aggregates,helped the generation and transformation of organic matter in aggregates,enhanced the stability of the aggregates and soil erosion resistance.