posted on 2023-05-26, 03:38authored byGatehouse, KA
Since the arrival of European settlers to Australia, many of Australia's unique ecosystems have been altered and under pressure. The main drivers of these changes have been land clearance for broad acre agriculture, the introduction of aggressive weeds, the reduction of native fauna due to habitat loss and predation by feral animals, like foxes and cats, and the gradual urbanisation of the landscape. In Tasmania these drivers have resulted in the loss and fragmentation of many temperate grassland and grassy woodland communities. The lowland Themeda grasslands currently make up less than 10% of the estimated pre-European extent and the lowland valley Poa grassland community is less than 15% of the pre-European extent. With only 9% of these communities currently protected under the National Reserve System, it is evident that many of these communities are fragmented, occurring predominantly on private land, along roadsides, cemeteries and islands‚ÄövÑvp isolated by spreading urbanisation. In order to better protect these vulnerable communities it is imperative that private land managers need to implement appropriate management regimes that encourage species diversity and abundance. The Pontville Small arms Range Complex is a Commonwealth owned site that is currently managed by the Defence Department as a military training facility. In 1999 a vegetation survey was undertaken to describe the lowland vegetation communities on the site and to review the management regimes in place. This study found 5 endangered 4 vulnerable and 4 rare flora species. It also identified that the vegetation communities provided habitat for a number of significant fauna species. An assessment of how these vegetation communities are doing a decade later has revealed that there has been a significant decline in species richness across all of the vegetation communities. The findings have also revealed that the management regime employed appears to have had little impact on the overall floristic composition or abundance. The factors driving this decline are a combination of seasonal effects, drought conditions and the additional pressures of grazing. It is unclear as to whether grazing alone has resulted in the general species decline, but no doubt in combination with the other environmental factors, grazing has not helped in protecting these vulnerable communities. A review of current grazing management and other management regimes seems to an appropriate course of action to maintain and improve the biodiversity of all of these vegetation communities.