Assessment of the Spatial Invasion Risk of Intentionally Introduced Alien Plant Species (IIAPS) under Environmental Change in South Korea

Abstract

Predicting the regions at risk of invasion from IIAPS is an integral horizon-scanning activity that plays a crucial role in preventing, controlling, and eradicating invasive species. Here, we quantify the spatial distribution area and invasion risk of IIAPS using a species distribution model under different levels of environmental change in South Korea. From the model predictions, the current average spatial extent of the 10 IIAPS is 33,948 km2, and the individual spatial extents are estimated to change by −7% to 150% by 2050 and by −9% to 156% by 2070. The spatial invasion risk assessment shows that, currently, moderate-to-high invasion risk is limited to coastal areas and densely populated metropolitan cities (e.g., Seoul, Busan, and Gwangju), but that the area with this level of risk is expected to spread toward the central and northern regions of the country in the future, covering 86.21% of the total area of the country by 2070. These results demonstrate that the risk of invasion by IIAPS is estimated to enlarge across the whole country under future environmental changes. The modeling system provided in this study may contribute to the initial control and strategic management of IIAPS to maintain the dynamic ecosystems of South Korea.

Climate change-induced invasion risk of ecosystem disturbing alien plant species: An evaluation using species distribution modeling

“…In another study, ten alien plant species that were intentionally introduced for horticulture, pasture improvement, and soil erosion control were assessed for their spatial invasion risk. Under future climate change scenarios, intentionally introduced species are predicted to spread to nontargeted ecosystems and occupy approximately 86.21% area of the country, which falls under the moderate-to high-risk category (Adhikari et al, 2021). Both of our previous studies identify rapid environmental changes that carry an increasing risk of alien weed invasion.…”

“…The problems caused by invasive species prompted us to study invasive weeds in South Korea under future climate change scenarios, to guide the development of measures to control their spread (Adhikari et al, 2021;Hong et al, 2021). In one study, 16 invasive weeds from the southern region (<36 • latitude) were evaluated.…”

“…Numerous risk assessment tools are used to quantify invasion risk of alien plant species (Morse et al, 2004;Robertson et al, 2021). Species distribution models (SDMs), for example, are widely used tools to assess the invasion risk of alien plants, and aid in designing conservation policies for their control and eradication (Bradley et al, 2010;Dullinger et al, 2017;Adhikari et al, 2021). SDMs resolve the ecological niche of plant species by statistical regression, machine learning, and spatial interpolation (Elith and Leathwick, 2009;Li and Wang, 2013;Zurell et al, 2020).…”

Climate change induced habitat expansion of nutria (Myocastor coypus) in South Korea

“…During modeling, the species occurrence data were randomly split into two parts, i.e., a training set and a test set, at a ratio of 3:1(as described in Adhikari et al 59 ) . The training data set was used for model fitting, which estimated the parameters of the model (model calibration).…”

“…The vulnerability of each AD was determined and classified into three categories (low, moderate, or high) based on the mean suitability values from 0‒0.33, 0.34‒0.66, and 0.67‒1.00, respectively. We used a linear scale to classify the vulnerability and the method of Adhikari et al 59 with minor modifications. M. coypus habitat expansion was determined by differentiating between the current and future habitats using R package ‘Raster’ v3.5 68 as described by Jeon et al 47 .…”