Modify livestock farming practices in watershed to reduce pollution
Overall effectiveness category No evidence found (no assessment)
Number of studies: 0
Background information and definitions
Livestock farming in watersheds can lead to pollution of focal marshes or swamps. Soil and nutrients can run off arable land and accumulate in wetlands, affecting the plant community composition, plant diversity and distribution of plant species (Meehan & Platts 1978; Verhoeven et al. 2006; Bromberg Gedan et al. 2009). Extreme excesses can cause algal blooms. Runoff is a particular problem on farmland that has been compacted due to trampling. Conversion of catchments to pastures also contributes to salinization and acidification, by raising the local water table and bringing salts to the surface. The main cause of this is the replacement of native deep-rooted vegetation with shallow-rooted pasture crops that don’t take up as much water – made worse if overgrazing stunts plant growth or creates bare patches (NSW Government 2019).
This action includes a range of specific actions, other than changes in fertilizer or herbicide use, that might reduce pollution from livestock farming in wetland catchments. These interventions include: completely excluding or removing livestock, reducing grazing intensity (by reducing duration and/or pressure of grazing), changing timing of grazing (e.g. avoiding grazing just before heavy rains) and changing the type of livestock (e.g. using sheep or goats rather than cattle if trampling is a problem). Studies in which livestock have access to marshes or swamps, and can graze directly within them, are considered in Chapter 3.
Related actions: actions to address the threat from livestock within wetlands, e.g. Use barriers to keep livestock off ungrazed sites (freshwater marshes – brackish/salt marshes – freshwater swamps – brackish/saline swamps); Reduce fertilizer or herbicide use (freshwater marshes – brackish/salt marshes – freshwater swamps – brackish/saline swamps); Manage fertilizer or herbicide application.
Bromberg Gedan K., Silliman B.R. & Bertness M.D. (2009) Centuries of human-driven change in salt marsh ecosystems. Annual Review of Marine Science, 1, 117–141.
Meehan W.R. & Platts, W.S. (1978) Livestock grazing and the aquatic environment. Journal of Soil and Water Conservation, 33, 274–278.
NSW Government (2019) Type of Salinity and their Prevention. Available at https://www.environment.nsw.gov.au/topics/land-and-soil/soil-degradation/salinity/type-of-salinity-and-their-prevention. Accessed 30 December 2020.
Verhoeven J.T.A., Arheimer B., Yin C. & Hefting M.M. (2006) Regional and global concerns over wetlands and water quality. Trends in Ecology and Evolution, 21, 96–103.