BURDEKIN DRY TROPICS NATURAL RESOURCE MANAGEMENT PLAN 2016-2026
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Runoff and eroded sediment also carry nitrogen and phosphorus away from the landscape into receiving environments such as waterways, wetlands and marine ecosystems. Rainfall simulation programmes in the Burdekin region have identified that nitrogen and phosphorous loss from‘ D’ condition land was seven to ten times greater than from land in better condition( Cowie, et al., 2013). The programmes identified that where rehabilitation had occurred following aggressive soil disturbance, water infiltration increased and nitrogen and phosphorous losses were lower.
In addition, dryland salinity outbreaks occur in isolated parts of our region within the Cape River and Campaspe River catchments, and parts of the upper catchment of the Suttor River. Loss of trees and native perennial grasses due to clearing and inappropriate grazing management have increased groundwater recharge in affected landscapes, giving rise to the observed salinity( Roth, et al., 2002). The Salinity Management Handbook is a comprehensive document developed by the Queensland Government to better understand, investigate and manage where salinity does or might occur.
Overall, changes to pasture management to maintain good ground coverage does have notable effects on land condition and the water quality of runoff leaving the land( Bartley, et al., 2014). Regionally, a significant effort is needed to improve and maintain land condition to build resilience and avoid continued deterioration of regional land and soil health.
Preferred management practices vary depending on factors such as land type, presence of a seed bed, erosion extent and topography. In some cases direct mechanical work is needed for specific locations, which will incur a significant initial cost, however it can lead to rapid improvements in the land condition and overall long-term productivity( Moravek & Hall, 2015). In other instances, less intensive methods can lead to significant improvements that are potentially more cost-effective, such as‘ stick trap’ check dams, or the use of short-term, ultra high density grazing in smaller paddocks, which uses cattle’ s hooves to grade eroded banks and spread manure to improve the seed bed( Wilkinson, et al., 2015)( NQ Dry Tropics, 2015c).
Grazing trials at Wambiana have proved that managing stock rates and wet season paddock spelling to maintain good groundcover can generate far more profit in the longer term than heavy stocking rates that also lead to land degradation( O’ Reagain & Bushell, 2015). Generally, it is more profitable to manage stocking rates in line with the long-term carrying capacity of the grazing land type.
A range of collaborative tools and extension programmes have been developed to help graziers access information on land capability and provide farm management options to improve land condition and resilience through best management practice; including the documents mentioned previously and online tools such as FORAGE, Stocktake Plus and NRM Spatial Hub( Queensland Government, 2016)( Future Beef, 2016)( Rangelands Alliance, 2016). Improved property management practices include undertaking actions that go beyond industry standard requirements, such as:
• mapping land types;
• assessing land condition annually;
• calculating long-term carrying capacity based on area, land types, land condition, pasture utilisation rates and infrastructure;
• applying strategies to restore or improve longterm carrying capacity;
• pasture budgeting;
• strategically locating watering points;
• wet season spelling;
• fencing sensitive environmental areas; and
• managing sheet and gully erosion( Carey, 2008)( O’ Reagain, et al., 2014),( McIvor, 2012)( Queensland Department of Agriculture, Fisheries and Forestry, 2013).
Example of‘ C’ condition land has:
• general decline of 3P grasses;
• large amounts of less favoured species;
• 20 – 40 % coverage at the end of the dry season;
• obvious signs of past erosion and / or current susceptibility to erosion is high;
• general thickening in density of woody plants.
Example of‘ D’ condition land has:
• general lack of any perennial grasses or forbs;
• < 20 % coverage at the end of the dry season;
• severe erosion or scalding;
• thickets of woody plants cover most of area.
LAND