Environmental and Historical Influences on the Vegetation of Central Europe

Abstract

We define Central Europe as the region outlined in Fig. 1.1. It includes Germany, the Netherlands, Belgium and Luxembourg, Switzerland, Austria, the Czech Republic, Slovakia and Poland, as well as parts of the neighbouring countries of Denmark, southern Sweden, eastern France and the Italian Alps. This central region of Europe, covering almost 1 million km², belongs to the northern temperate zone and is roughly bisected by the 50th parallel. Accordingly, its climate is characterised by moderately warm, frost-free summers and fairly cold winters, which for most plants means several months of quiescence. The contrast between the two seasons is made less severe by the position of Central Europe between the oceanic west and the increasingly continental east (see Fig. 1.2), so that the air temperature in summer rarely rises beyond 30 °C, and in winter it only drops below −20 °C in exceptional cases (see Maps 1.1 and 1.2 at the end of Chap. 1). The position of Central Europe also means that the transitional seasons of spring and autumn are relatively long, extending the growth period for many plants. The Central European vegetation additionally benefits from the fact that cyclonic rain falls throughout the year (Walter 1979; see Map 1.3 at the end of Chap. 1). Longer periods of summer drought therefore occur only sporadically (e.g. 1904, 1911, 1921, 1947, 1949, 1959, 1964, 1973, 1976, 1982/1983, 1990, 2003, 2006, 2010 and 2015; Rocznik 1981; Kowalski 1991 and other sources), especially in relatively continental regions. Catastrophic cold periods are also rare (e.g. 1928/1929, 1939/1940, 1955/1956, 1962/1963; Rocznik 1985).