Humic substances in ecosystems (HSE11) : book of abstracts and field session guide, 11th international conference, 29 May - 1st June, 2017, Wroclaw-Kudowa Zdrój, Poland. -- 1st. ed. -- Wrocław : Uniwersytet Przyrodniczy, 2017. -- 95 s. pôda * humusové pôdy * environmentálne riziká * ochrana životného prostredia