4.4 Terrestrial Communities
T ABLE 4.41 Comparison of climate change with other threats to successional communities
Rank Order
Threat
Comments
Conversion to Agriculture/ Silviculture
1
Te greatest threat to this habitat group is habitat loss due to development of more intensive agricultural and silvicultural practices. Modern, indus- trialized farming leaves fewer unutilized areas in and adjoining felds, such as hedgerows, groves of shade trees, and weedy forest-feld ecotones. Fewer felds are left fallow for very long. Pastures and hayfelds are more intensively managed, using heavier applications of herbicides, pesticides, and fertilizers. Mowing of hayfelds is also now conducted much more frequently than it has been in the past. More pressure will be placed on the utilization of marginal agricultural or silvicultural lands for energy production, including the development of otherwise “green” sources such as biomass, wind, and solar energy. Increased frequency and severity of environmental perturbations may disproportionately afect ecosystems composed primarily of annuals or rstrategist species in general, particularly if landscapes continue to become more and more fragmented. Communities may be in close proximity to areas that are commonly quite polluted. Farm felds and pine plantations are regularly sprayed with biocides or fertilizers; powerline rights-of-way are now routinely sprayed with herbicides to keep them open; roadside rights-of-way are subject to pollutant laden runof from the road surfaces as well as application of salt and other chemicals used to prevent icing in the winter; ruderal areas located near industrial areas are subject to both air- and waterborne pol- lutants emanating from the industrial plants. All of these pollutants can play a major role determining species viability within the semi-natural habitats used by this group. Two species that are likely to spread into new areas, particularly at higher elevations due to increased temperatures, are Kudzu and Fire Ants. Both of these exotic species have strong impacts on early successional and other ruderal habitats. Along with changes in agricultural practices, loss of some habitat patches or connections between them may be attribut- able to the smothering invasion of kudzu. Impacts from land use changes are likely to accelerate at least indirectly due to climate change, with more demand for biofuels or other forms of energy production utilizing “waste grounds.” Like other native ecosys- tems, early successional habitats are also likely to be afected by increased temperatures, prolonged droughts, more frequent fres and storms, and especially invasion of exotic species.
Fragmentation
1
Pollution
2
Invasive Species
2
Climate Change
3
noted in this group of species is likely due to decreased connectivity between habitat patches, in addition to the decreased extent of these habitats overall.
Disturbed and artifcially created/maintained habitats are particularly susceptible to invasion by exotic species, which in some cases can have signifcant impacts on the native species associated with early successional habitats. While most compositional
485
2015 NC Wildlife Action Plan
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