Table 2 Land equivalent ratio under different systems.

1. Lettuce yield (g plant⁻¹)

61.1^a

42.2^a

0

2. Lettuce yield (kg ha⁻¹ year⁻¹)

97,760^a−d

67,520^a−d

0

3. Lettuce income (USD ha⁻¹ year⁻¹)^c,d

296,213

204,586

0

4. Energy income (USD ha⁻¹ year⁻¹)

0

46,538^{c, e}

108,588^{c, f}

5. Total income (USD ha⁻¹ year⁻¹)

296,212

251,124

108,588

6. Land Equivalent Ratio (LER)

1.00

1.12

1.00