The importance of timing and number of surveys in fungal biodiversity research

Abstract

Practical conservation of biological diversity is dependent on reliable knowledge about what kind, how much, and where the diversity is. To obtain such knowledge three questions, why, what, and how, must be answered before commencing any biodiversity survey. While the questions why and what are often value decisions and thus determined outside the realm of scientific research, the question about how the surveys are conducted lies in the heart of science. Here, we report an intensive repeated survey of wood-inhabiting fungi with the aim of determining the optimal timing and number of the surveys for reliable estimation of the diversity of this species group. The research focusing on the ecology of wood-inhabiting fungi has been increasing but little is known about the reliability of the methods. The variation in the estimates of diversity among surveys was high and the results varied between studied species groups. The site-scale detectability for species belonging to different groups varied from 10 to 95% depending on the survey month and the species group. We conclude that because detectability of many fungi turned out to be poor even when surveys were conducted at an optimal time, the common practice of using a single fruit body survey to estimate fungal diversity of any given area is not enough. We suggest that multiple surveys at an optimal time should be a norm in fungal diversity studies. Improper methodology results in unreliable outcomes that have potential to hamper our goal of conserving the biological diversity.

Polypore communities in broadleaved boreal forests

“…It is true that our method loses some of the accuracy typical for sample plot studies. Of course the decision of the optimal sampling strategy like survey type (Stokland and Sippola 2004), selection of the studied dead wood pieces (Juutilainen et al 2011) and number of surveys conducted (Halme and Kotiaho 2012) is largely dependent of the questions asked in a particular study. In this context, if the aim is to collect species lists to obtain a general figure of the species pool and its ecology in a given biotope, opportunistic survey may be a more efficient tool than the usual sample plot-based surveys.…”

“…The polypore inventories were carried out in 2007 and 2008 during August-October, which is the peak fruiting season of polypores in the study area (Halme and Kotiaho 2012). We used the Nordic concept of polypores, meaning all the poroid Aphylloporales, a delimitation that is widely used in northern Europe (Niemelä 2005, Junninen andKomonen 2011).…”

Linking molecular deadwood-inhabiting fungal diversity and community dynamics to ecosystem functions and processes in Central European forests

“…However, the macroscopically observable fungal flora may not be fully representative of the fungal community that is present, especially if sampling is only conducted once or over a short period of time (Halme and Kotiaho 2012). In contrast, high-throughput sequencing allows for detailed analysis of community composition and may thus uncover a hitherto concealed fungal diversity residing in deadwood.…”

The history and future of fungi as biodiversity surrogates in forests

“…Step 2: Select surrogate candidates that are easy to record and identify To be easy to record, surrogates should have long-lasting fruit bodies or at least a long fruiting season (Halme & Kotiaho 2012;Abrego et al 2016, Purhonen et al 2016). Polypores and stromatic pyrenomycetes are ideal as they fruit for a substantial part of season.…”