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Nitrogen inputs can be reduced to minimize N losses to the environment while maintaining yields but N recommendations must reflect seasonal temperature effects.Abstract Two-year greenhouse cucumber experiments were conducted to investigate seasonal effects on fruit yield, dry matter allocation, and N uptake in a double-cropping system with different fertilizer management. Seasonal effects were much greater than fertilizer effects, and winterespring (WS) cucumber attained higher fruit yields and N uptake than autumnewinter (AW) cucumber due to lower cumulative air temperatures during fruit maturation in the AW season. Fertilizer N application and apparent N loss under recommended N management (Nmr) decreased by 40e78% and 33e48% without yield loss compared to conventional N management (Nmt) over four growing seasons. However, there were no seasonal differences in N recommendations, taking into consideration seasonal differences in crop N demand, critical nutrient supply in the root zone and N mineralization rate.

Enclosures have been set-up in rangelands in China since about 1980 to control grazing. This was performed in order to favour the recovery of degraded vegetation and soil. Alpine desert rangeland is an important ecosystem in China, and enclosure was considered a means of rangeland restoration for long-term grazing. Soil properties were studied in a 6-year enclosure experiment, which found that without grazing, vegetation cover and aboveground plant biomass increased significantly. A positive, but not significant, trend in soil bulk density was also found. However, the storage of soil carbon (C), nitrogen (N) and phosphorus (P) decreased insignificantly after 6 years of enclosure. The ratio of C:N and C:P of soil increased in the (0-10)-cm and (10-20)-cm layers but decreased in the (20-30)-cm layer. In conclusion, prevention of grazing for 6 years did not significantly improve soil quality or potential carbon sequestration in the alpine desert rangelands. We recommend the removal of fences intended for rangeland and biodiversity protection from such landscapes.