Productivity and water resource-use efficiency are crucial issues in sustainable agriculture, especially in high-demand water resource crops such as soybean [Glycine max (L.) Merr.]. The aims of this research were to compare planting pattern in soybean, evaluating soil moisture content (SMC), yield and water use efficiency (WUE). A 2-year field experiment (2006–2007) was carried out in the north of China. The summer soybean (cv. Ludou 4) experiment consisted of 5 planting patterns under the same plant population density (3.09 × 105 plant/ha), and row spacing (cm) × plant spacing (cm) was 18 × 18 cm (A), 27 × 12 cm (B), 36 × 9 cm (C), 45 × 7.2 cm (D), 54 × 6 cm (E). The results showed that SMC and soil storage water (SSW) decreased with evapotranspiration (ETa) increments after reproductive growth stage, and there were remarkable differences between treatments with decreasing rainfall. SMC curve characteristics in the 0–0 cm soil profile were related to rain; the scope changes of shallow SMC were higher than those of deep SMC. The study revealed that yield and WUE had a negative correlation with row spacing, and they were statistically greater in narrow rows, which approximated equidistant plant spacings, compared to wider rows (P < 0.05). The study also indicates that enhanced productivity and WUE of rainfed summer soybean can be achieved via row spacing reduction and plant spacing widening under uniform planting density.

To gain new insights into the underlying mechanisms responsible for farmland microclimate and yield of winter wheat under different row spacings [row spacing: 7 cm (RS7); 14 cm (RS14); 24.5 cm (RS24.5); 49 cm (RS49)], field experiments were conducted at Taian, China. Between the hours 13:00 and 14:00, low values of relative humidity (RH) and air temperature at 5 cm above the ground for the various row spacings were obtained. The average RH of RS7, RS14, RS24.5, and RS49 was 91.0%, 90.3%, 85.7%, and 76.4%, respectively; the average air temperature were 22.6°C, 23.2°C, 24.3°C and 25.3°C, respectively. The soil temperature of RS49 was higher than those of RS7 and RS14. The maximum values of eddy thermal diffusivity was 0.07 m 2 s -1 , as well as sensible and soil heat fluxes, were obtained at 12:00 o'clock. The order of these parameters was similar to that of the air temperature, but opposite to that of the latent heat flux. The yield of RS49 was significantly lower than those of the other treatments (P < 0.05). The present study indicates that excessive row spacing may result in severe dissipation of energy. RS14 is the optimum condition under uniform planting density. 2 akışının yanı sıra en yüksek termal difüzyon katsayısı 0.07 m 2 s -1 olup bu değer saat 12'de ölçülmüştür. Bu parametrelerin sıralaması hava sıcaklığı parametrelerinin sıralamasına benzer olmuş ancak gizli ısı akışı parametrelerinin sıralamasının tam tersi bir durum göstermiştir. Sıra arası 49 cm olduğu durumdaki uygulamanın diğerlerinden belirgin bir şekilde daha düşük olmuştur (P < 0.05). Araştırma sonuçlarına göre, sıra arası mesafesinin artması, enerji kaybında büyük kayıplara yol açtığını göstermiştir. Düzgün bir bitki dağılımı için en uygun koşullar açısndan sıra arası mesafenin 14 cm olduğu belirlenmiştir.