Suburban development and resultant changes in the vegetation of the bushland of the northern Sydney region

Abstract

Bushland sites in the northern suburbs of Sydney were compared to sites in Brisbane Waters National Park, Ku-ring-gai Chase National Park and Royal National Park which are relatively unaffected by suburban development. Both shale-derived and sandstone-derived soil infour physiographical locations were examined, with three replicates of each of the 16 combinations.Phosphorus levels are higher in the soils of suburban sites compared to soils derived from similar rock bases in non-suburban sites. Phosphorus levels are also higher on shale-derived than on sandstonederived soils, and lower on hilltops than in other physiographic positions. Suburban sandstone sites have soil phosphorus levels similar to those of nonsuburban shale sites.Three major and three minor clusters of species were distinguished using a hierarchical agglomerative clustering. The major clusters consisted of (1) species commonly associated with wet sclerophyll forests and rainforest margins, (2) species directly or indirectly related to the presence of man, and (3) species associated with dry sclerophyll forests and heaths.Using analyses of variance and covariance, arui logit models, the abundance of the first main cluster was related to nutrient-rich soils and the abundance of the third main cluster to low nutrient soils whereas the presence of the second main cluster was almost entirely restricted to sites surrounded by suburbs.The development of suburbs around vegetation patches has led to an increase in the abundance of native and exotic mesomorphic species and the Present address: Macleay Building.

Nutrient limitation along the Jurien Bay dune chronosequence: response to Uren & Parsons ()

“…While it is clear that crop species have different nutrient requirements than native species, crop species can nonetheless provide useful indicators of nutrient limitation. For example, Beadle (1954) used tomato seedlings in a similar nutrient addition experiment to show that P was the key limiting nutrient on soils around Sydney, Australia, which has been supported subsequently by other lines of evidence (Beadle 1962;Clements 1983;Leishman et al 2007).…”

The effect of fragmentation on the threatened plant community Coastal Moonah Woodland in Victoria, Australia

“…Disturbed urban remnants are characterised by a diversity of opportunistic and often exotic species that are effective dispersers (Moffatt and McLachlan 2004). These species thrive in urban environments; both in gardens and native remnant communities that boast artificially elevated levels of soil phosphorous (Clements 1983;Moffatt and McLachlan 2004). Thus minimising disturbance, through restricting access via fencing, combined with targeted weed control are some key long-term management actions to ensure the preservation of this community for future generations.…”

Floristic patterns and disturbance history in karri forest, south-western Australia

“…Clarke and Schedvin, 1999;Schefler et al, 2001). Thus, human associated disturbances generally favor introduced species (Denslow, 1985;McIntyre and Lavorel, 1994), and artificially increased nutrient and moisture levels are important causal factors of exotic species incursion in low nutrient Australian environments (Clements, 1983;Hobbs, 1989;McIntyre and Lavorel, 1994;Prieur-Richard and Lavorel, 2000). Alterations of disturbance regimes result in shifts in species composition, with the loss of less tolerant native species, a decrease in native diversity, and increased exotic diversity (McIntyre and Lavorel, 1994;Prieur-Richard and Lavorel, 2000).…”