玉米/大豆不同种植模式对土壤有机质和全氮空间分布的影响

土壤中有机质和全氮的空间分布，及其在土壤微生态、养分循环和农业可持续发展等方面有着巨大的现实意义。因此，本试验于2018—2020年，研究了土壤有机质和全氮在带状套作玉米/大豆连作(MS1)、带状套作玉米/大豆轮作(MS2)、传统套作玉米/大豆(MS3)、玉米单作(M)、大豆单作(S)和休闲地(FL)6个模式下的含量及空间分布。结果表明，套作土壤全氮大豆行含量大于玉米，不同种植模式下有机质含量存在显著差异(P<0.05)。土壤有机质(29.19 g·kg^-1)和全氮(10.19 g·kg^-1)以MS2含量最高。FL土壤有机质含量(1.69 g·kg^-1)和全氮含量(0.64 g·kg^-1)最低。本研究认为，MS2是较好的带状套作种植模式，该模式能增加土壤有机质和全氮的空间分布，从而提高土壤肥力和C∶N比。

Effects of Different Maize/Soybean Planting Patterns on Spatial Distribution of Soil Organic Matter and Total Nitrogen

The spatial distribution of organic matter and total nitrogen in soil has great practical significance in soil microbiology,nutrient cycling and agricultural sustainable development. Therefore,this field experiment was conducted in 2018-2020 to study the effect of different planting patterns arrangements of maize and soybean inter-cropping on spatial distribution of soil total nitrogen and organic matter contents. The planting patterns included continuous maize/soybean relay strip inter-cropping (MS1),maize/soybean relay strip inter-cropping in rotations (MS2),Traditional maize/soybean inter-cropping (MS3),sole maize (M),sole soybean (S),and fallow land (FL). The results showed that the total nitrogen content of soybean row in intercropping soil was higher than that of maize,and the organic matter content was significantly different under different cropping patterns (P<0.05). MS2 had the highest soil organic matter and total nitrogen,29.19 g·kg^-1 and 10.19 g·kg^-1,respectively. In contrast,FL's soil organic matter content was 81.69 g·kg^-1 and total nitrogen content was 0.64 g·kg^-1,both of which were the lowest. It indicated that MS2 was the best planting pattern for strip relay inter-cropping,which could increase spatial distribution of soil organic matter and total nitrogen,consequently,improve the soil fertility and C:N ratio.