Rice growing seasons

(A)

Treatments (B)

Rice-Shrimp crabs mixed farming with soil amendments

Grain yield

(kg·ha⁻¹)

Gross return (Tk./ha)

Total variable cost

(Tk./ha)

Cumulative CH₄ flux (kg ha⁻¹ season⁻¹)

GWP

(kg CO₂ eq. ha⁻¹)

Net return Tk. ha⁻¹

Benefit to cost ratio (BCR)

Wet season (rainfed aman)

T₁: Rice sole cropping without NPKS, and no soil amendments

1500 g

48,000 g

57,000 f

133.5 d

3337 d

-

0.84 d

T₂: Rice sole cropping (NPKS, farmers’ practice) without soil amendments

3500 ef

96,000 f

82,500 d

181.0 a

4525 a

13,500 f

1.16 cd

T₃: Rice sole cropping (FP) with PG

3600 e

99500 ef

85,000 c

166.0 b

4150 ab

14,500 f

1.17 cd

T₄: Rice-Shrimp mixed culture with PG

3700 de

112,000 de

90,500 b

151.6 bc

3790 bc

21,500 d

1.23 bc

T₅: Rice-Crabs mixed farming with PG

3300 f

106,500 e

88,500 bc

133.0 d

3325 d

18,000 de

1.20 c

T₆: Rice-Shrimp mixed farming + PG with Spirulina

3900 d

115,500 d

91,500 b

121.0 e

3025 e

24,000 cd

1.26 bc

T₇: Rice-Crabs mixed farming + PG with Spirulina

3500 ef

110,000

de

92,500 b

115.7 e

2767 f

18,500 e

1.19 cd

Dry season (boro)

T₁: Rice sole cropping without NPKS, and no soil amendments

1000 h

30,500 h

65,500 e

121.0 e

3025 e

-

0.51 e

T₂: Rice sole cropping (NPKS 100%) without soil amendments

3750

115,000 d

90,000 b

167.0 b

4175 ab

20,000 cd

1.22 bc

T₃: Rice sole cropping (FP) with PG

3900 ab

128,500 cd

98,500 ab

155.0 bc

3875 b

30,000 bc

1.30 b

T₄: Rice-Shrimp mixed culture with PG

4100 ab

140,700 b

105,200 a

141.0 c

3525 c

35,500 b

1.34 ab

T₅: Rice-Crabs mixed farming with PG

3800 c

127,000 cd

99,500

ab

129.0 d

3225 d

27,500 c

1.28 bc

T₆: Rice-Shrimp mixed farming + PG with Spirulina

4500 a

143,500 a

105,000 a

117.0 e

2925 e

38,500 a

1.37 a

T₇: Rice-Crabs mixed farming + PG with Spirulina

4000 cd

130,500 c

101,500

ab

105.6 f

2640 f

29,000 bc

1.29 bc

ANOVA

A

*

**

**

*

*

**

*

B

*

**

**

**

**

**

**

A × B

*

**

**

*

*

**

*