摘要
砂姜黑土结构不良是影响其生产力的主要限制因子。为改良其土壤结构,基于安徽龙亢农场砂姜黑土耕作定位试验基地,设置免耕、旋耕、深松和深翻四种处理,研究不同耕作方式对砂姜黑土0~40 cm土层土壤物理结构、玉米根系发育及其产量的影响。结果表明:1)在玉米生育期内,免耕处理下0~40 cm土壤平均容重和紧实度分别为1.52~1.57 g·cm^-3和926~1748 kPa,高于其他耕作处理;0~10 cm土层有效水分库容和饱和导水率低于其他耕作处理,分别仅为0.12 cm^3·cm^-3和3.5×10^-5 mm·min^-1;根系发育受到明显抑制,根长密度和根干物质的量密度较其他耕作方式分别降低42.5%~117%、35%~73.9%;2016—2017周年作物产量较深松和深翻降低8%~12%。2)与旋耕和深松相比,深翻处理下10~20 cm土壤容重和10~30 cm土壤穿透阻力分别降低至1.39~1.51 g·cm^-3和725~1575 kPa,0~10 cm土壤饱和导水率显著提高至4.15×10^-2 mm·min^-1,0~20 cm土壤有效水分库容提高至17.9%~18.4%,促进了0~10 cm土层根系发育,具有较好的增产效果。3)相关分析表明根长密度与土壤容重(r=-0.74^**,P<0.01)和穿透阻力(r=-0.73^**,P<0.01)呈极显著负相关关系。综上所述,深翻改良砂姜黑土结构效果明显,有利于作物生长,为该区较适宜的耕作模式。
【Objective】Shajiang black soil is one of the major types of soil low or medium in productivity in China.As its parent material is dominated with montmorillonite and high in clay content,the soil is high in bulk density and strength and low in water permeability.These characteristics of the soil are the main factors limiting root development and yield of crops.Tillage practices,such as subsoiling and deep ploughing,have been considered as effective management practices to improve soil structure,but their adaptability varies quite significantly with region.How to adopt effective tillage practices to improve soil structure,expand available water capacity,promote root development and increase crop yield is of great significance to safety and stability of the grain production in this region.The objective of this study was to evaluate systematically effects of tillage practices on soil physical properties and maize growth in Shajiang black soil.【Method】A long-term field experiment in the Longkang Farm,Anhui Province was initiated in 2015 and designed to have four treatments different in tillage practices,including no tillage,rotary tillage,subsoiling and deep ploughing.Each treatment had three replicates,making up a total of 12 plots,laid out in a single factor randomized block design.Soil bulk density in the 0~10 cm,10~20 cm and 20~40 cm soil layers and penetration resistance of the 0~45 cm soil layer were measured separately at different growth stages of maize.Features of the root system of maize in the soil profile were measured only at the milk-ripe stage.Soil available water capacity,saturated hydraulic conductivity and some other soil physical properties in the three layers were determined separately and yield of the crop was calculated after the crop harvested.At the end,relationships between crop growth with physical properties were analyzed.【Result】1)Compared with the other three treatments,the no-tillage one was higher in bulk density(1.52~1.57 g·cm^-3)and in soil penetration resistance(926~1748 kPa),but lower in soil available water capacity(0.12 cm^3·cm^-3)and in saturated hydraulic conductivity(3.5×10^-5 mm·min^-1)in the 0~40 cm soil layer depth throughout the entire maize growing period.Consequently,the root length density and root dry biomass density in that treatment were significantly declined 42.5%~117.1%and 35%~73.9%,respectively,in the 0~10 cm soil layer than those in the other treatments.The no-tillage treatment was also 8%~12%lower than the others in crop yield for three successive years.2)Relative to the treatments of rotary tillage and subsoiling,the treatment of deep ploughing was lower in bulk density(1.39~1.51 g·cm^-3)in the 10~20 cm soil layer and in soil penetration resistance(725~1575 kPa)in the 10~30 cm soil layer,but higher in saturated hydraulic conductivity in the 0~10 cm soil layer and in soil available water capacity in the 0~20 cm soil layer.Consequently,the plants in that treatment were higher in root density and crop yield than those in the other two treatments.3)Pearson correlation analysis shows that plant root density was significantly and negatively related to soil bulk density(r=-0.74^**,P<0.01)and soil strength(r=-0.73^**,P<0.01)for the whole growing period.【Conclusion】It is,therefore,concluded that the deep ploughing may be a more appropriate tillage practice to improve soil physical properties and promote crop agronomic performance in the Shangjiang black soil.
作者
王玥凯
郭自春
张中彬
周虎
洪亮
王永玖
李录久
彭新华
WANG Yuekai;GUO Zichun;ZHANG Zhongbin;ZHOU Hu;HONG Liang;WANG Yongjiu;LI Lujiu;PENG Xinhua(Institute of Soil Science,Chinese Academy of Sciences,Nanjing 210008,China;University of Chinese Academy of Sciences,Beijing 100049,China;Longkang Farm of Anhui Province,Huaiyuan,Anhui 233426,China;Institute of Soil and Fertilizer,Anhui Academy of Agricultural Sciences,Hefei 230031,China)
出处
《土壤学报》
CAS
CSCD
北大核心
2019年第6期1370-1380,共11页
Acta Pedologica Sinica
基金
国家重点研发计划项目课题(2016YFD0300809)
国家自然科学基金项目(41725004,41771264)
农业部行业专项课题(201503116)共同资助~~
关键词
砂姜黑土
深翻
土壤结构
根系特征
作物产量
Shangjiang black soil
Deep ploughing
Soil structure
Root characteristic
Crop yield