西南玉米生态区域划分及品种需求

目的探讨云南省石灰岩红壤坡耕地的主要耕作方式(旋耕、浅翻)和其他耕作措施(深翻、深松)在该地区的适宜性。方法选取云南典型的石灰岩红壤坡耕地，通过2年玉米种植大田试验，探讨不同耕作措施(免耕、旋耕15 cm、翻耕20 cm、翻耕30 cm和深松30 cm)下的土壤容重、总孔隙度、紧实度以及玉米地上部性状和玉米产量特征。结果与常规旋耕相比，深松30 cm可显著降低土壤容重和紧实度，分别达4.65%和15.23% (2016年)、8.21%和14.22% (2017年)，同时，可提高土壤孔隙度，但免耕则相反。2017年，深松30 cm的玉米产量较常规旋耕显著增产11.47%，但2016年免耕的玉米产量显著低于常规旋耕，减产达14.57%。结论深松耕对云南石灰岩坡耕地玉米的生长和产量具有一定促进作用，是试验区较为适宜的耕作措施，在生产中具有一定的参考价值。

Tillage influence on biophysical soil properties: the example of a long-term tillage experiment under Mediterranean rainfed conditions in South Spain

PurposeTo explore the suitability of the main tillage methods (rotary tillaging and shallow ploughing) and other farming practices (deep tillage and subsoiling) for the sloping land of limestone red soil in Yunnan Province.MethodsThe soil bulk density, total porosity and compactness, and the agronomic traits of corn plant and yield were observed. In this study, we selected the typical sloping land with red soil developed from limestone for maize production in Yunnan Province, and conducted a two-year experiment. The experiment was designed with different tillage measures (no-tillage, rotary tillage 15 cm, tillage 20 cm, tillage 30 cm and subsoiling 30 cm). The soil bulk density, total porosity and compactness, growth and yield of maize field were measured.ResultsCompared with conventional rotary tillage, subsoiling 30 cm significantly decreased the soil bulk density and compactness by 4.65% and 15.23% (2016), 8.21% and 14.22% (2017), respectively. But the effect of no-tillage is opposite. The maize yield in 30 cm deep was significantly higher and than that in conventional rotary tillage (2017), while the yield in no-tillage was significantly lower 14.57% than that in conventional rotary tillage (2016).ConclusionSubsoiling can promote the growth and yield of maize in limestone sloping farmland in Yunnan Province, which are more suitable tillage measures in the experimental area.