Areas at risk of pine wilt disease spreading globally due to climate change

Potential distribution of pine wilt disease under future climate change scenarios

Akiko Hirata (a), Katsunori Nakamura (b), Katsuhiro Nakao (c), Yuji Kominami (c), Nobuyuki Tanaka (d), Haruka Ohashi (a), Kohei Takano (e), Wataru Takeuchi (f), Tetsuya Matsui (a)

 (a) Center for International Partnerships and Research on Climate Change, FFPRI, Tsukuba, Ibaraki, Japan.

 (b) Tohoku Research Center, FFPRI, Morioka, Iwate, Japan.

 (c) Kansai Research Center, FFPRI, Kyoto, Japan.

 (d) Tokyo University of Agriculture, Tokyo, Japan.

 (e) Nagano Environmental Conservation Research Institute, Nagano, Japan.

 (f) University of Tokyo, Tokyo, Japan.

PLoS ONE, 12(8): e0182837, August 2017, DOI: 10.1371/journal.pone.0182837( External link )

Pine wilt disease caused by the pine wood nematode, which has been devastating pine forests in Japan, is recently damaging forests across East Asia and Western Europe. Because the incidence of pine wilt disease is closely associated with temperature, there is increasing concern of the disease spreading to northern areas due to ongoing climatic warming. The regions where climatic conditions will become unsuitable for pine distribution grow increasingly vulnerable to pine wilt disease.

In this study, we evaluated the risk of pine wilt disease in 21 susceptible pine species within their natural distribution area under current and future climate conditions on a global scale. We also evaluated the impact of climate change on habitat suitability for each pine species.

Consequently, we found that large parts of pine distribution area in East Asia and Southern Europe are at risk under the current climatic conditions, with pine wilt disease already spread in most of these high-risk areas. We also predicted that the high-risk areas may spread to Eastern Europe, Central Asia, and Russian Far East with future climatic warming. Under the climatic change scenario in which there may be a significant rise in temperature, the entire high-risk area is predicted to expand to 50% of the natural distribution of susceptible pine forests, 40% of which may even become completely unsuitable for pine growth.

If climate change progresses, regions further north may also be required to take measures against pine wilt disease. The findings of this study are expected to provide invaluable basic information for countries that are striving to prevent further expansion of the disease, thereby contributing to control the damage associated with climatic changes.

Figure. Areas at risk of pine wilt disease and those unsuitable for pine distribution under the climatic change scenario in which the average temperature is expected to rise by 3.7°C (Representative Concentration Pathways Scenario 8.5) in the 2070s (excerpt from DOI: 10.1371/journal.pone.0182837).

The areas marked in dark brown represent those which are predicted to be at a high risk of pine wilt disease and unsuitable for pine distribution. In such areas, pine trees may be subjected to more harsh environmental conditions than those observed at present, thereby increasing the risk of the disease.