Anthropogenic Stressor

Stresses which are directly caused by the actions of humans, rather than by natural non-organic (abiotic stressor) or biological means (biotic stressor). This type of stressor might, however, typically be included within that of abiotic stressor. Examples include:
• Soil compaction especially from machinery use or players.
• Misapplication of chemicals, especially pesticides, reducing plant or soil health.
• Climate change, which is having a major impact on global environments, but also influences extremes of weather, such as flooding, droughts and very high temperatures (all abiotic stressors), all of which impact on plant health.
• Nutrient pollution to soil and watercourses, from misapplication or overapplication of fertilisers (providing an excess of nutrients) for the prevailing conditions. Leaching on sand profile pitches can be a potential issue.
• Lack of nutrients, not being addressed by adequate fertiliser regimes, especially where clippings are routinely removed from a sward.
• Soil acidification by material application, especially from overuse of acidifying fertilisers or soil conditioners, for example, elemental sulphur.
• Erosion, from overuse of a surface, so user management is an important factor, as is an understanding of the carrying capacity of a sports surface.
• Management practices which introduce or encourage undesirable plant species which compete with desirable species for available resources.
• Mechanical stress through poor machinery settings, for example, a blunt cylinder blade which will provide a surface which is more susceptible to disease infection (a biotic stressor), or by carrying out maintenance work when conditions are inappropriate, for example, scarifying when growth is minimal or dormant.
• Excess rootzone temperatures due to undersoil heating, stressing grass roots.
• Excess supplementary lighting forcing grass growth, producing softer, weaker cells and leaf matter making the plant more easily worn and susceptible to disease attack.
• The use of unsterilised top-dressing could introduce undesirable pathogens to a sward.
• Playing conditions which occur when the soil surface is frozen or thawing surface layer, saturated soil profile, or drought stressed / wilting, will all be detrimental to plant health.