Potential global distribution of Aleurocanthus woglumi considering climate change and irrigation

of North and South America. The Sahara Desert, central Australia, New Zealand, Korea, most of Europe, Canada and Russia are among the countries or regions with unfavourable condi- tions. In terms of the model parameters, dry stress and hot stress mostly limit its distribution in desert areas and inland Australia, whereas temperature and cold stress limit its distribution in northern Europe, Canada and Russia. Climatic conditions are projected to be marginal in many warm temperate areas, such as southern Europe and northern New Zealand. Under irrigation, favourable habitat suitability is projected for A. woglumi in areas in which it is not known to occur or persist, such as Jordan, Madagascar, southern Japan, eastern Aus- tralia, north-eastern Argentina, north-eastern Bolivia, eastern Mozambique, areas in Somalia, North Africa and eastern Saudi Arabia (Fig 1). Distribution records for A. woglumi in Iran, India, Oman, Yemen and some locations in Sinaloa in Mexico are modelled as being climati- cally unsuitable under the natural rainfall scenario, but climatically suitable under the irriga- tion scenario (S1 Fig). Under the irrigation scenario (under current climate), the percent area of potential distribution (EI>0) is increased on all continents except for Oceania (Table 2). Further validation was carried out by comparing the number of generations modeled and reported in the literature at various locations. Hoelmer and Grace [29] reported that in south Florida (USA) three to four generations occur annually. Our model calculated about 3.8 in the

southern parts. Clausen and Berry [67] stated that close observations upon this species in Kuala Lumpur (Malaysia) produced five generations each year, which is consistent with our modelled estimate of 4.5 annual generations. In the Panama Canal Zone, at least on the Pacific side, during the dry season at least one generation is lost, making the maximum number of generations five instead of six [33]. Our model simulations estimated that A. woglumi has about 4.8 generations in the Canal Zone. Sensitivity analysis and model uncertainty Parametric sensitivity analysis identifies those parameters that are most important for model accuracy. Of concern are those parameters that are both sensitive and least reliably estimated. In relation to the modelled potential range, the dry stress threshold (SMDS) is the most sensi- tive parameter (5.3%) (S2 Table). The remaining parameters each have less than 1% sensitivity. The dry stress threshold is well anchored in biological theory, as the permanent wilting point of plants is a well-studied and consistent phenomenon, so we can be confident in this parame- ter. The dry stress accumulation rate is a fitted parameter, with moderate uncertainty, though the sensitivity is also very low (0.9%). The low sensitivity in the range change in the sensitivity analysis provides confidence in the model [44]. Model uncertainty is presented in S2 Fig. The strong concordance between the areas of high model agreement in S2 Fig (red areas) and the extent of area modelled with EI>0 in Fig 1 indicate that despite the limited amount of distribu-

tion data we can be confident in the fitted parameter set. Future climate projections Suitable areas for pest establishment were quantified in terms of their expected future expan- sion or contraction under the RCP8.5 ACCESS1-0 model as compared to the areas modelled as suitable in the presence of irrigation under current climate projections (Fig 2B). The pro- jected increase in suitable areas in comparison to those under current climate is relatively modest, with most of this expansion occurring within Europe. In Asia, North America, Ocea- nia, and South America there are increases in the regions that are modelled with EI>0 for A. woglumi of 11, 15, 2, and 1%, respectively, while in Europe the potential distribution increases by 90%, though from a very low base of �300 000 km2 (Table 2). Future climate projection in Africa suggests a decrease of 2%. PLOS ONE Potential global distribution of Aleurocanthus woglumi PLOS ONE | https://doi.org/10.1371/journal.pone.0261626 December 20, 2021 9 / 18