Impacts and management cost of pine invasions in Patagonia

NUÑEZ, MA; MARTINEZ, A

Curitiba

Congreso; IUFRO; 2019

IUFRO

Forestry plantations with nonnative species is an important economic resource in many parts of the world, but these plantations can generate environmentalproblems. One of these problems is the invasions in neighboring communities. Here we study the impacts of Lodgepole pine (Pinus contorta) invasion,probably the most invasive forest species in the southern hemisphere. We analyzed its impact on biodiversity, ecosystem services, and fuel load. We comparednon-invaded zones with invaded zones of contrasting densities, and areas where invasive trees had been removed. We also evaluated the costs of pine invasionremoval. We found that Pinus contorta has a high impact only when it reaches high densities This gives some hope because it indicates that there is a relativelylong period (10 years from the beginning of the invasion) during which appropriate management should be conducted. Removing pine invasions was veryeffective to reduce fire risk. However, after one year the removal of pines did not result in improvements in biodiversity indices or ecosystem services metrics.Post-removal sites in areas with previous high pine density were colonized by nonnantive plants. Control costs grew with the increase in density of pines. Ourresults show that if managers focus on early interventions, numerous environmental impacts can be avoided and the costs of invasion management will bereduced. However, if forestry practices continue to ignore invasions, environmental impacts may reach an unprecedented level given the high probability offuture pine invasion in the Southern hemisphere.