National Key R&D Program of China（2018YFD0200700; 2016YFD0200309-7）
[Objective] Planting pattern is an important factor affecting soil physico-chemical properties, dietary preference of soil fauna, and hence soil water and nutrient movement in a soil profile. This study aims to evaluate characteristics of the common planting patterns in the basin and screen out one suitable to the calcareous purple soil in the central Sichuan basin.[Method] Based on a long-term in situ field experiment, three planting patterns, i.e. maize-wheat (MW), maize-oil rape (MR) and maize-sweet potato-wheat (MWP), were selected for comparison in this study. Using laboratory analysis in combination with the computer tomography micro-scanning technology, analysis was performed of effects of the planning patterns on soil physical properties, nutrient status and soil fauna and on calcareous purple soil quality and productivity as well. Moreover, pros and cons of the planting patterns were distinguished to select suitable planting patterns[Result] Number of the pores 25~500 μm in equivalent aperture in the cultivated layer, was ultra-significantly and positively related to content of soil organic matter, total nitrogen (N) and available N, separately, which implies that the pores contribute greatly to storage of soil organic matter, total N and available N in the cultivated layer. However, number of the pores > 500 μm in equivalent aperture was ultra-significantly and positively related to content of available phosphorus (P), which indicates that large-size pores are conducive to retention of available P. In terms of organic matter, total N, available N and available potassium (K) in the cultivated soil layer, the three planting patterns all exhibited an order of MW > MR > MWP. Treatment MW was higher than the other two in compactness of the 0~20 cm soil layer and in looseness of the >35cm soil layer; with pores 25~1 000 μm and > 1 000 μm in equivalent aperture accounting for 50.2% and 49.8%, respectively, of the total pore volume, forming a proper proportion of pores, evenly distributed and well connected, which contributes greatly to soil structure and soil quality. However, in Treatment MW, soil fauna was lower in total population than in the other two. Consequently the treatment was the lowest in annual total yield and economic output. Treatment MR was quite similar to Treatment MW in soil physical properties with pores 25~1 000 μm and > 1 000 μm in equivalent aperture accounting for 31.6%, and 68.4%, respectively of the total and being poorly connected; however, the treatment was significantly higher than the other two in total population and species of scavenger soil animals and more significant in soil available P accumulation. Treatment MWP had a plough layer loose in texture, and was significantly higher than that in the other two Treatments in saturated water content, saturated conductivity, mean porosity soil fauna abundance and annual crop yield and economic output; in the Treatment pores 25~1000μm and > 1000μm in equivalent aperture accounted for 20.5% and 79.5%, respectively, and higher proportion of the latter facilitated downward movement of water and nutrients, thus leading to lower contents of soil available P and readily available K and exposure to higher risks of nutrient consumption and loss; moreover, the treatment was much higher in abundant and species variety of soil animals.[Conclusion] The three planting patterns are the traditional ones in the area and all have their own advantages and disadvantages. It is advisable to choose site-specific ones and to make full use of the pros and avoid the cons. The MW pattern leads to formation of a plough layer with soil pores reasonable in proportion and good in connectivity, which is conducive to water and nutrient conservation and soil sustainable utilization, however, the pattern tends to be lower in soil fauna abundance and economic benefits than MR and MWP. Though MR is worse in soil pore structure than MW, it is conducive to abundance of saprophytic soil fauna, which helps improve the soil structure and hence higher in economic benefit than MW. MWP is the highest in economic benefit and its crop types and pore structure are good to the survival and reproduction of soil fauna, however, the pattern causes soil pore structure unfavorable to water and nutrient retention. So it may need higher nutrient input to keep high stable yields, which is negative to soil nutrient accumulation and long-term fertility.
马胜兰,况福虹,唐家良,王艳强,吴鹏飞,朱波.种植模式对川中丘陵石灰性紫色土结构和地力的影响[J].土壤学报,2021,58(4):935-947. DOI:10.11766/trxb202002210685 MA Shenglan, KUANG Fuhong, TANG Jialiang, WANG Yanqiang, WU Pengfei, ZHU Bo. Effects of Planting Patterns on Soil Structure and Fertility of Calcareous Purple Soil in Hilly Areas of Central Sichuan Basin[J]. Acta Pedologica Sinica,2021,58(4):935-947.复制