Response of Forest Phyllophagous Insects to Climate Change

Abstract

Modern climate characteristics have a strong impact on plants, insects, and biogeocoenotic relations among them. This is unambiguously supported by multiple studies worldwide, the reports of which are briefly reviewed in the present article. Most of the authors agree that air temperature is the most important factor directly affecting the development and population level of insects. Ranges of plant and insect species are shifting northwards and to higher altitudes. Phenological phases come ahead of time in spring and later in fall, which results in longer growth season. Time-series analysis and trends in five major weather elements in the southern forest-steppe zone in Voronezh oblast have revealed the weakening of climate continentality, increased precipitation over the growth period, and a higher frequency of extreme weather events. Additionally, the study detected changes in the population-level dynamics of insects, specifically, the gypsy moth, the green oak leaf roller, and the winter moth, which commonly occur on this plot, and the disturbance in their relations with host plants. The harmfulness of some species declines, while that of other species rises. Modeling allows one to predict some consequences of the direct effects of climate change on relationships between phyllophagous insects and their host plants. Delayed consequences associated with indirect climatic forcing are hard to predict. They will depend on the character of climate change and on response of plants and insects driven by their adaptation mechanisms.