�
� farming practices and other farmers ( 8 per cent ) as the top causes . They also mentioned coral bleaching , water deoxygenation , water turbidity , and poor government policies ( e . g . water pricing systems in the Burdekin irrigation area ) as other causes of poor water quality .
Approximately 61 per cent of respondents did not believe their farming practice adversely impacts water quality in local streams , rivers , and waterways and 66 per cent did not believe that the industry plays a significant role in the declining health of the GBR . Many respondents tended to shift the blame related to water quality and the health of the GBR to other industries , organisations and individuals .
Participants were also asked what they consider the top two pressures to be on the health of the Great Barrier Reef . The top pressures cited were climate change and global warming ( 21.6 per cent ); nutrient and sediment run-off ( 13.5 per cent ); urban run-off ( 5.4 per cent ); extreme weather events ( e . g . cyclones , an increase in sea temperature ) ( 5.4 per cent ); tourism industry ( 5.4 per cent ); and shipping accidents , anchor damage and oil spills ( 5.4 per cent ). They also cited mining , natural growth and decline , fishing , and natural changes / cycles .
While these results cannot be considered to be representative of the region , they are in line with results from previous studies and is useful information for understanding the barriers and enablers to practice adoption when considered with other lines of evidence such as feedback from extension staff and project managers .
As described in Section 6.3.1 , the ability of individuals to adopt a practice may also be constrained by skills , capacity or the ability to adopt a new technology . For example , there is potential to be significant implementation issues with broadscale adoption of advanced irrigation techniques in terms of capacity to design , install and operate these more sophisticated systems – let alone the comparatively high costs ( see below ). Feedback from industry in the development of the Burdekin WQIP 2016 indicated that the most suitable options will be site specific , and will range from optimised / automated furrow irrigation , low pressure overhead irrigation , drip irrigation and in some cases , methods combined with recycle pits .
The large upfront costs associated with adopting higher efficiency irrigating practices are likely to provide challenges for large scale adoption of these techniques until further information is available to demonstrate benefits to farm profit ( Alluvium , 2016 ). The uncertainty associated with selecting the most suitable irrigation methods for achieving B class irrigation methods could be overcome with more site-specific assessments , although these could become costly . However , if developed in conjunction with other management improvements such as nutrient management , the efficiencies and benefits are likely to be substantial ( refer to sections above on management options ).
6.3.2 The costs of management practice change
A synthesis of the literature on key agricultural economics studies involving sugarcane farm management systems and practices has been completed by DAF ( Poggio et al ., 2014 ; Thompson et al ., 2014 ) and for pesticides , as a component of the Reef Water Quality Protection Science Program project RP62C Economics of pesticide management on cane farms ( Smith et al ., 2014 ). A summary of this work is provided in Waterhouse et al . ( 2016 ). As part of the supporting studies for the Burdekin WQIP 2016 , Smith ( 2015 ) also conducted a financial-economics analysis to evaluate the total weighted cost / benefits to transition between ABCD management classes using traditional capital budgeting methods . More recently , several specific trials and case studies have been evaluated by DAF , considering offsetting changes in costs and productivity ( see publications . qld . gov . au / dataset / best-management-practices-for-sugarcane ). There was some ( but not conclusive ) evidence from trials in the Burdekin that use of enhanced efficiency nitrogen fertilisers instead of urea could be at least cost neutral ( Thompson et al ., 2016a ), and similar results showing that banding mill mud may generate positive returns in some cases ( Thompson et al ., 2016b ). However , the high capital costs made low-cost drip irrigation in the Burdekin generally unprofitable , even though it reduces management costs and increases yields ( Thompson et al ., 2016c ).
From these studies , improved irrigation management is expected to incur a cost to growers , and this can be significant when reaching ‘ B class ’ or Moderate to Low risk irrigation efficiencies . Investment is likely to be
49