Page 104 - Soil Degradation, Conservation and Remediation

3.4 Control of Water Erosion 91

Fig. 3.14 Contour strip cropping (Photo courtesy of USDA-NRCS)
strips must be maintained between strips in soils with severe erosion. These strips

can be used as traffic lanes for cultural operations (Blanco and Lal 2008 ).

3.4.8 Sloping Agricultural Land Technology (SALT)

SALT is a technology package of soil conservation and food production that
integrates several soil conservation measures (Tacio 1993 ). It involves planting fi eld
crops and perennial crops in bands 3–5 m wide between double rows of nitrogen-
fixing shrubs and trees planted along the contour. Thus, it is a modification of the

contour strip cropping, but it may be practiced in land of slope more than 10 %.
Field crops include legumes, cereals, and vegetables while the main perennial crops
are cacao, coffee, banana, citrus, and fruit trees (MBRLC 1988 ). The nitrogen-

fixing trees are thickly planted in double rows to make hedgerows (Fig. 3.15 ). When
a hedge is 1.5–2 m tall, it is cut down to about 75 cm, and the cuttings are placed in
alleyways to serve as organic fertilizers. SALT establishes a diversifi ed stable eco-
system. SALT was developed on a marginal site in the Philippines by the Mindanao
Baptist Rural Life Center (MBRLC) in 1971. There are ten steps in establishing a
SALT farm:
Step 1 Making the A-frame: A-frame is a wooden frame of two legs in the shape
of English alphabet “A” having a water or sprit level on the middle arm.
Step 2 Drawing contour lines: Contour lines are drawn by joining the points of
equal elevations selected by the A-frame in a slope.