Adinandra belukar: an anthropogenic heath forest in Singapore

Abstract

Adinandra belukar is a species-poor forest dominated by Adinandra dumosa (Theaceae) found in Singapore and southern Peninsular Malaysia. It is the product of secondary succession after exhaustive agricultural exploitation on land cleared of primary lowland rain forest. A high degree of similarity in vegetation between different sites was found for seven 225 m 2 plots in adinandra belukar in Singapore.Adinandra dumosa was dominant or codominant in all plots, generally found in association with the woody species Dillenia suffruticosa, Fagraea fragrans, and Rhodamnia cinerea, the climber Gynochthodes sublanceolata, the fern Dicranopteris Iinearis and the terrestrial orchid Bromheadia finlaysoniana. All sites had extremely acidic (pH 3.3-3.9) surface (0-20 cm) mineral soils with very low total nitrogen (0.06-0.14~o) and total phosphorus (11-29 #g g -l ) contents and very high carbon/nitrogen ratios (33-48). Adinandra belukar is interpreted as a heath forest because of its floristic and physiognomic similarities with this forest formation.Nomenclature: follows Turner, Chua and Tan (1990), A checklist of the native and naturalized vascular plants of the Republic of Singapore.

Slow recovery of a secondary tropical forest in Southeast Asia

“…In addition, a final piece of evidence that supports the conjecture that our secondary forest soils were likely impoverished is the striking lack of fast-growing Macaranga trees, which are usually one of the first trees to establish in Southeast Asian secondary forests (Brearley et al, 2004;Cheke et al, 1979;Shono et al, 2006). Macaranga are also more diverse and abundant in nutrient-rich secondary forest (Wyatt-Smith, 1963), but almost absent on forest with impoverished soil (Sim et al, 1992). We found only seven Macaranga individuals from three species in the secondary forest plot, as compared to 16 Macaranga individuals in the primary forest plot.…”

“…Previous studies have shown that the continued persistence of ''long-lived pioneers'' (Finegan, 1996) can slow down the replacement of light-demanding species by shade-tolerant primary forest species (Finegan, 1996;Corlett, 1995). In our secondary plot many of the most abundant species, including A. dumosa, D. suffruticosa, R. cinerea and Fagraea fragrans, are long-lived and slow growing (Sim et al, 1992;Corlett, 1991aCorlett, , 1995. We posit that these long-living species occupy the space and take up the resources (e.g., nutrients and water) needed for successful recruitment and growth of more shade-tolerant species.…”

“…Westoby et al (2002) showed that low foliar nitrogen and phosphorous content and high leaf mass per area are typical nutrient conserving characteristics of plants that thrive on poor soil; high leaf mass per area in turn is correlated with slow turnover of plant parts and slow growth. In our particular study system, A. dumosa, D. suffructicos, R. cinerea, and F. fragrans have been commonly found on soil impoverished after decades of exhaustive agricultural use (Corlett, 1991a;Sim et al, 1992). In addition, a final piece of evidence that supports the conjecture that our secondary forest soils were likely impoverished is the striking lack of fast-growing Macaranga trees, which are usually one of the first trees to establish in Southeast Asian secondary forests (Brearley et al, 2004;Cheke et al, 1979;Shono et al, 2006).…”

Neotropical rainforest restoration: comparing passive, plantation and nucleation approaches

“…In these situations plant species richness quickly increased within the first few decades, especially for species with smallersized stems (Guariguata and Ostertag 2001;Norden et al 2009), and later there was a clear convergence with mature forest community composition, supporting an equilibrium model of succession (Norden et al 2009). However, some degraded tropical ecosystems may remain in a state of arrested forest succession (Sim et al 1992;Chapman and Chapman 1999;Hooper et al 2005;Goldsmith et al 2011;Ortega-Pieck et al 2011;Chazdon 2014). Under high disturbance conditions, as mining areas, for example, where soil removal, compaction or degradation has occurred, a site may never return to a state similar to original conditions (Gómez-Pompa et al 1972;Uhl et al 1988;Martínez-Garza and Howe 2003;Chazdon 2008b) but instead cross a threshold into a disclimax or emerge as a novel ecosystem .…”

Overlooked flower-visiting Orthoptera in Southeast Asia

“…It is unclear exactly why a predatory katydid would visit flowers, but we suspect that it is eating the pollen in the anthers of the smaller stamens at the base of the whorl of larger stamens. This species may be exploiting a cheap source of protein since adinandra belukar (a species-poor, anthropogenic heath forest dominated by Adinandra dumosa Jack [Sim et al 1992]) tends to be more faunistically depauperate because of the poorer soils in this forest type (Sim et al 1992, Chua et al 2013.…”