Potential impacts
• The Burdekin Region contains extensive areas of coastal and marine ecosystems including estuarine systems , seagrass and coral reefs . These ecosystems provide important habitat for a range of highly valued fish species , marine mammals and bird species . Many of these systems are vulnerable to increases in sediment loads in the environment .
• Flood plume studies have found most sediment exported from the Burdekin Rivers is deposited within close proximity of the river mouth / estuary , near-shore zone and inner shelf of the GBR , with potential for remobilisation during subsequent wind and tide driven resuspension events . Such resuspension events can result in higher turbidity levels than measured in initial flood plumes . The delivery of this new sediment to the inner shelf sediment wedge plays a critical role on inshore turbidity regimes , with a recent study highlighting the influence of increased river flow / sediment loads on temporal variation in inshore turbidity . Turbidity reduces light for benthic organisms such as seagrass and corals . Coastal coral reefs do grow in turbid water conditions at shallow depths , however biodiversity declines as a function of increased turbidity throughout the GBR . Variability in light conditions may be a greater stress than chronically reduced light , as energy demands to adjust to varying light conditions result in suboptimal energy gains .
• Sediment properties strongly influence the effects of sedimentation on corals . Nutrient enriched fine terrestrial silts found along the inshore GBR are most detrimental . Early life stages ( e . g . fertilisation , settlement ) of corals are particularly susceptible to poor water quality and sedimentation .
Past and present programs
• The BBB catchment has received significant extension efforts and the roll-out of projects and programs as part of a decade long engagement effort for water quality improvement and land management practice changes across the Burdekin River basin and GBR catchments more broadly . This report provides an overview of the known incentive support , extension and engagement that has been conducted in the BBB catchment over the last decade .
• There has also been a great deal of research and monitoring activity in the BBB catchment with a focus on sediment sources and delivery , grazing management practices and more recently , landscape remediation ( e . g . targeting gully and streambank erosion ).
• There is a significant opportunity to benefit from past and present programs in the BBB catchment through the BMIP and forma mechanisms to facilitate program linkages and alignment will be necessary .
Knowledge about adoption of management practices in the BBB
• While there is little BBB-specific data , the material presented in this document is relevant to understanding landholders in the BBB catchments and sends a cohesive message . There is no evidence to suggest that landholders in the BBB are different from landholders elsewhere in the Burdekin or northern Australia .
• It is critical to understand the causality of adoption decisions . Likelihood to adopt BMPs cannot be gleaned from socio-economic property descriptors such as size of operation , geographical location , type of ownership , age and education level of operator , and previous experience with conservation programs . Adoption decisions are guided by the principal motivations that drive the decision maker ( s ) in any given situation , their attitudes and risk perceptions . Motivations are broadly defined by economic-financial , stewardship-lifestyle and social motivations . Landholder motivations and perceptions are heterogeneous .
• Tailoring policies and programs to a diverse set of preferences is critical for maximising landholder participation . Tailoring is particularly important in situations where the participation of geographically identifiable landholders can be critical to achieving a ( water quality / biodiversity / etc ) conservation goal .
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