Secondary sucession at abandoned grazing sites, Pangandaran Nature Reserve, West Java, Indonesia

Abstract

The Pangandaran Nature Reserve (PNR) is a 530-ha peninsula on the southeastern coast of West Java. It was designated as game reserve for ungulates in 1934 and as a nature reserve in 1961. Four grasslands (49 ha in total) were established as grazing sites in 1921, but some were abandoned (Batu Meja for 55 years and Badeto for 30 years), and the others were irregularly managed (Nanggorak) or frequently managed (Cikamal) by cutting and burning. We compared these different management histories to describe secondary succession at these sites where we set plots to measure the diameter at breast height of all woody species taller than 130 cm and the canopy cover of all shorter individuals. At three sites except Batu Meja we recorded the maximum height and coverage of each species in transects crossing the sites. The area of open grassland decreased from 41 ha around 1977 to 4 ha in 2011. The dominant grasses in Cikamal and Nanggorak changed from tall Imperata cylindrica to low creeping grasses, Ischaemum rugosum and Eleusine indica. Melastoma malabathricum invaded these grasslands , from surrounding areas. Tectona grandis (teak) has been planted in the reserve s public-use zone since 1932 and widely invaded the grasslands. Badeto became a young secondary forest dominated by Psychotria cf. robusta and Guioa pubescens. Batu Meja has been occupied by lowland tree species such as Buchanania arborescens and Diospyros hermaphroditica. These changes suggest that management will be essential in the remaining grasslands to preserve their ability to support ungulate populations.