Climate suitability predictions for the cultivation of macadamia (Macadamia integrifolia) in Malawi using climate change scenarios

suitability for macadamia in Malawi and contributed 60.2% towards macadamia suitability. Pre- cipitation of the driest month (May–November) and precipitation seasonality accounted for more than 40% in determining the suitability for macadamia. Precipitation of the driest month is the variable with the greatest relative influence (29.1%) on the suitability for macadamia. Temper- ature variables contribute 39.8% towards macadamia suitability in Malawi. Among the tempera- ture variables, isothermality (17.3%) (calculated by dividing mean diurnal temperature range by mean annual temperature range) was the most significant. Our model results found that annual means do not affect the suitability for macadamia production in Malawi. 3.3.Current suitability for macadamia in Malawi Results of the present (~1970–2000) suitability analysis reveal that 57% (53,925 km2) of the surface area in Malawi is suitable for macadamia production, with the largest area (25.8%, which is 24,327 km2) in the central region of the country (Table 3, Fig 5). Of the 57% that is suitable, optimal suitability (26%, 24,565 km2) is observed in the highland parts of the country with elevations ranging from 1000–1400 m.a.s.l. Notably, in some parts of Dowa, Chitipa, Mulanje, Mwanza, Mzimba, Ntchisi, Nkhatabay, Rumphi, and Thyolo districts (S2 Table). Moderate suitability (22.4%, 21195 km2) is projected in the mid-hills between 950–1000 m.a.s. l. in the districts of Blantyre, Chiradzulu, Dedza, Kasungu, Lilongwe, Mchinji, and Zomba.

Marginally suitable areas were found to be in the lower elevated (� 900 m.a.s.l) parts of Malawi. Because of the topography, the districts of Neno and Ntcheu have both optimal and marginally suitable areas for macadamia (Fig 5). Furthermore, according to our model Fig 4. The importance of a variable in explaining macadamia suitability in Malawi. Data is obtained from the averages of the 18 species distribution model algorithms. https://doi.org/10.1371/journal.pone.0257007.g004 Table 3. Area and percentage suitable for growing macadamia under current climatic conditions. Region Area (km2) Percentage (%) Central 24,327 25.8 Northern 19,341 20.5 Southern 10,257 10.7 Total 53,925 57 https://doi.org/10.1371/journal.pone.0257007.t003 PLOS ONE Macadamia integrifolia: Climate suitability of Malawi PLOS ONE | https://doi.org/10.1371/journal.pone.0257007 September 9, 2021 10 / 20