The effect of severe drought and management after drought on the mortality and recovery of semi‐arid grassveld

Abstract

The False Thornveld of the Eastern Cape experienced a particularly intense drought during the 1982/83 growing season. Extensive grass mortality took place during the drought. After the drought, recovery was particularly sensitive to the post‐drought management treatment applied. Veld that was grazed immediately after the drought recovered far more slowly than veld that was rested. This effect was still evident three years later, illustrating the considerable importance of resting semi‐arid grassveld after a drought.

Increaser I grass species present were apparently more capable of surviving drought than the Decreaser species, which in turn were more stable than the Increaser II species. Their ability to recover after the drought followed an opposite trend. On this basis, the desirability of Decreaser dominated veld, in situations that are likely to be poorly managed, is questioned.

Uittreksel

Gedurende die 1982/83 groeiseisoen het die Skyn‐doringveld van die Oos‐Kaap ‘n besonder intense droogte ondervind. Gedu‐rende die droogte het grootskaalse afsterwing van graspolle voorgekom. Na die droogte was die herstel van die veld besonder sensitief ten opsigte van die weidingsbehandeling wat toegepas is. Veld wat direk na die droogte bewei is, het aansienlik stadiger herstel as die watgerus is. Dit illustreer die noodsaaklikheid van ‘n rusperiode in die semi‐ariede grasveld na droogte.

Toenemer I grassoorte was beter in staat om ‘n droogte te oorleef as Afnemersoorte, wat op hulle beurt weer meer bestendig vertoon het as Toenemer II soorte. Hulle herstelvermoë na droogte het ‘n omgekeerde neiging getoon. Op hierdie basis word die wenslikheid van Toenemer gedomineerde veld in situasies waarswak bestuur te sprake is, bevraagteken.

Additional index words:

• Grazing capacity
• species composition
• tillers
• tufts
• veld condition