An examination of long-term ecological studies of rotifers: comparability of methods and results, insights into drivers of change and future research challenges

Long-term research (LTR) can provide insights into rotifer ecology that are not possible from short-term studies or experiments. However, such studies have become rarer in recent years due to budgetary constraints. This review examined 5023 published articles about rotifers to determine the number, location and types of LTR studies that had been undertaken. Forty-four articles reported the results of studies that spanned more than 10 years. Of these, most focused on the impacts of climate change, acidification/liming and eutrophication/recovery on waterbodies and soils. However, some investigated ecosystem function, especially in relation to the effects of invasive species or the development of cost effective and comparable sampling techniques. The types of sites examined in these LTR studies included lakes and reservoirs, rivers, lagoons, seas and estuaries and soils, with the lengths of LTR records ranging from 10 to 82 years. Although their geographical locations ranged from North and South America to Asia, the Middle East and Europe, no studies were found from Africa, Australia or Antarctica. This review explores the role of LTR in quantifying the effects of environmental change and highlights gaps in existing knowledge.