Runoff and soil loss on a sandveld in Rhodesia

Abstract

Runoff and soil loss from veld treated in various ways was measured over a ten‐year period on a sandy soil with a 4 per cent slope in south‐western Rhodesia. The runoff as a percentage of the mean annual rainfall varied from 3.8, where the veld was left undisturbed, to 30.3, where the soil was kept bare artificially. The corresponding mean annual soil losses were 0.228 and 4.482 tons per acre (0.511 and 10.047 tonnes per hectare).

The data for certain treatments were used to derive regression equations which allow for the estimation of runoff from, records of the amount and intensity of rainfall.

UITTREKSEL

Afloop van water en grondverlies van veld wat op verskillende wyses behandel is, is gemeet oor ‘n tien‐jaar periode op sanderige grand teen ‘n helling van 4 persent. Die afloop, uitgedruk as ‘n persentasie van die gemiddelde jaarlikse reenval, het gewissel van 3.8 waar die veld onversteur gelaat is, tot 30.3 waar die grondoppervlakte kunsmatig bloot gehou is. Die ooreenstemmende jaarlikse gemiddelde grondverliese was 0.228 en 4.482 ton per acre (0.511 en 10.047 tonnes per hektaar).

Die data vir sekere behandelings is gebruik om regressievergelykings af te lei wat toelaat dat afloop geskat kan word vanaf rekords oor die hoeveelheid en intensiteit van reënval.