Current conditions There is evidence that there has been a decline in small floods in the past decade as a result of water use; prolonged drought and potential effects of climate change.
Under the future climate models; there was a range of potential climate estimates ranging from extreme wet to extreme dry.
These actions contribute to managing drought conditions and adapting to the potential impacts of climate change in the longer term.
Moisture deficits at very low levels; due to a changing climate (see section 7.2); increase the likelihood of destructive fire in the coming years. 7.5 Invasive species Invasive plants and animals can be broadly defined as species that have undesirable impacts; which may be economic; environmental or social and can include native as well as exotic taxa.
The three aspects of climate that most directly affect wetland ecology are rainfall (both local and in the catchment); temperature and (to a lesser extent in temperate systems) relative humidity as these all fundamentally affect wetland hydrology and the water budget.
Note that the climate as described here is relevant to the time of listing; the issue of climate change is dealt with under threats (see section 7).
Gibbons and Lindermayer (2002) suggest that the sustainable conservation of habitat trees must account for senescence; storm or bushfire damage to existing habitat trees and recruitment of future habitat trees from younger age classes. 7.4 Altered fire regimes Fire shapes the composition and distribution of many plant and animal communities across Australia and is a vital part of many Australian ecosystems.
Inappropriate fire regimes; however; can be a threat to wetland ecosystems.
Unfavourable fire regimes include intense; destructive wildfires but also low intensity fires if their frequency; seasonality or extent has a negative impact on biodiversity.
Although mature river red gum trees can survive low intensity fires (MacNally and Parkinson 2005) saplings are fire sensitive (Dexter 1978) with even fires of moderate intensity sufficient to damage the cambium leaving the stem susceptible to secondary attack by fungal pests.
Flooding after high intensity fire may cause large quantities of ash to enter the river system which may dramatically change the aquatic environments of downstream rivers (Forests NSW 2008a).
In recognition of the significant threat that destructive fires pose to the river red gum estate Forests NSW has developed a number of strategic planning and fire suppression measures to ensure fires are minimised; but when they do occur; are detected and suppressed as soon as possible.
The reduction in seasonal flooding; that historically maintained uncured grass fuels through summer; has increased fuel availability of grasses that now cure each year through the summer; significantly increasing the bushfire hazard.
A major wild fire under extreme conditions could destroy or damage a significant proportion of the timber resource within the Koondrook Perricoota Forest Group.
Long term; potential loss of large Medium hollow bearing trees; affecting (long term breeding habitat. effects) Altered fire regimes Death of mature river red gums.
Increased risk of destructive wildfire through increased understorey biomass.
Human disturbance Loss or degradation of habitat Medium Current (recreation) through unauthorised firewood collection Soil and riparian zone degradation by off road vehicles or watercraft Increased risk of destructive wildfire Acid sulphate soils Generation of sulphuric acid Low Long term leading to mortality of flora and fauna (eg. fish kills) and degraded water quality.
This critical service is linked to changes in the frequency and duration of wetland wetting and drying as well as changes in extent and condition of wetland vegetation.
This critical service is linked to changes in the frequency and duration of wetland wetting and drying as well as changes in extent and condition of wetland vegetation.
The results of each of these are slightly different and highlight the difficulty (and uncertainty) in characterisation of flood frequency for the forests.
Vegetation health is generally poor and declining; particularly in the Koondrook Perricoota Forest Group (MDBC 2007d) and The extent and composition of vegetation communities is changing in response to altered flood regimes (Leitch 1989 Bowen 2005).
The duration; seasonality; frequency and intensity of wetting and drying determines the type of biota that occurs on the floodplain and wetting and drying can provide important cues for flora and fauna in reproductive cycles.
Inundation of river red gums maintains tree health; but plants must cope with low oxygen concentrations in saturated soils Inundation of flood plain marshes; extent of wetland area increases as intermittent wetlands fill.

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