Research and information

Rainfall

The last 13 years of below average rainfall, in addition to tight water restrictions since 2002, has highlighted the importance of researching landscape water use, water conservation and irrigation efficiency.  The development of expertise in irrigation science has contributed to the reduction in water consumption by about 50% since 1994-95. Studies are also being carried out to compare and quantify plant water use, and to assess the levels of soil moisture that are adequate to maintain plant survival under conditions of stress. Water-repellent soils are another area of concern and trials have been set up across the landscape to discover the best ways to improve the water-holding capacity of the soil.

Climate Change

Climate change and its impacts on south-east Australia are amongst the most serious issues facing the future survival of the Gardens landscape. Current estimates suggest annual average rainfall in Melbourne could be reduced by 15% and average temperatures increased by about 4^oC by 2070.  Understanding the rainfall patterns and how these changes may affect soil moisture is vital for future planning of the landscape. Research is also directed towards building the knowledge of climates and associated plants that are similar to the current and projected climates of Melbourne to improve choices in plant selection.

Aquatic Biodiversity

Enhancing aquatic biodiversity in the lakes system is another important objective at RBG Melbourne. Regular blue-green algal blooms are a symptom of poor ecological condition in the Ornamental Lake and they also adversely affect the lake ecosystem. Investigations are underway to better understand the causes of these blooms and how the water quality of the lake might be improved. Scientific knowledge to date has resulted in a significant increase in the establishment of water plants (macrophytes), changes to horticultural practices and a greater understanding of the problems associated with the artificial feeding of birdlife.