Fig. 1 shows the various cultivation patterns for ridge and furrow
rainwater harvest system, conventional ridge planting and
flat gravel–sand mulch watermelon field. All treatments were
arranged in a randomized complete block design with 3 replications.
The gravel–sand mulch was a mixture of gravel (size range
1–4 cm) and coarse sand (3 mm).
For treatments 1, 7 and 8, the land was first leveled. All
treatments received 30 mg of manure, 150 kg of N, and 90 kg of
P2O5 ha−1. The ridge of treatment 7 was built and mulch with
plastic film, and seeds were seeded in the ridge. For the RFRHS treatments,
ridges were built first, and then manure and fertilizer were
applied in the furrows. After that the furrows were mulch with
gravel–sand and plastic film, seeds were seeded in the furrows.
Watermelon (Xinong-8) was seeded at an in-row spacing of
1.0 m in rows that were 0.6 m apart in late April. Plant density
was approximately 15,000 plants ha−1. Irrigation of 23 mm was
applied for treatment 8 during blooming stage. Watermelon harvest
started in late July. Total number of melons and their weight