TY  - JOUR
A1  - Pätzig, Marlene
A1  - Kalettka, Thomas
A1  - Onandia, Gabriela
A1  - Balla, Dagmar
A1  - Lischeid, Gunnar
T1  - How much information do we gain from multiple-year sampling in natural pond research?
JF  - Limnologica : ecology and management of inland waters
N2  - Natural ponds are perceived as spatially and temporally highly variable ecosystems. This perception is in contrast to the often-applied sampling design with high spatial but low temporal replication. Based on a data set covering a period of six years and 20 permanently to periodically inundated ponds, we investigated whether this widely applied sampling design is sufficient to identify differences between single ponds or single years with regard to water quality and macrophyte community composition as measures of ecosystem integrity.

In our study, the factor "pond", which describes differences between individual ponds, explained 56 % and 63 %, respectively, of the variance in water quality and macrophyte composition. In contrast, the factor "year" that refers to changes between individual years, contributed less to understand the observed variability in water quality and macrophyte composition (10 % and 7 % respectively, of the variance explained). The low explanation of variance for "year" and the low year-to-year correlation for the single water quality parameter or macrophyte coverage values, respectively, indicated high but non-consistent temporal variability affecting individual pond patterns. 

In general, the results largely supported the ability of the widely applied sampling strategy with about one sampling date per year to capture differences in water quality and macrophyte community composition between ponds. Hence, future research can be rest upon sampling designs that give more weight to the number of ponds than the number of years in dependence on the research question and the available resources. Nonetheless, pond research would miss a substantial amount of information (7 to 10 % of the variance explained), when the sampling would generally be restricted to one year. Moreover, we expect that the importance of multiple-year sampling will likely increase in periods and regions of higher hydrological variability compared to the average hydrological conditions encountered in the studied period.
KW  - water quality
KW  - macrophytes
KW  - space
KW  - time
KW  - kettle holes
KW  - conservation
Y1  - 2020
U6  - https://doi.org/10.1016/j.limno.2019.125728
SN  - 0075-9511
SN  - 1873-5851
VL  - 80
PB  - Elsevier
CY  - Amsterdam [u.a.]
ER  -