Phenological mapping in a topographically complex landscape by combining field survey with an irradiation model

CHYTRÝ, Milan and Lubomír TICHÝ. Phenological mapping in a topographically complex landscape by combining field survey with an irradiation model. Applied Vegetation Science. Uppsala: Opulus Press, 1998, vol. 1, No 2, p. 225-232. ISSN 1402-2001.

Basic information

• Original name: Phenological mapping in a topographically complex landscape by combining field survey with an irradiation model
• Authors: CHYTRÝ, Milan (203 Czech Republic) and Lubomír TICHÝ (203 Czech Republic).
• Edition: Applied Vegetation Science, Uppsala, Opulus Press, 1998, 1402-2001.

Other information

• Original language: English
• Type of outcome: Article in a journal
• Field of Study: 10600 1.6 Biological sciences
• Country of publisher: Sweden
• Confidentiality degree: is not subject to a state or trade secret
• WWW: URL
• RIV identification code: RIV/00216224:14310/98:00000707
• Organization unit: Faculty of Science
• UT WoS: 000208471900008

Abstract

A phenological map has been prepared for the Podyjí/Thayatal National Park, located on the border between the Czech Republic and Austria. The area is characterized by V-shaped river valleys deeply incised into a gently undulating landscape. Five stages of phenological development were defined based upon phenological spectra of plant communities in late April, and 96 sites more or less regularly spaced over the area were assigned to one of these stages using field observations of the phenological spectra. Potential direct solar irradiation was calculated from a digital elevation model for a 25 x 25 m grid extending over the study area. A method was developed for interpolation of phenological observations by weighted regression of phenology on the irradiation model. This interpolation method makes it possible to predict the local stage of phenological development everywhere across the study area without levelling out phenological patterns dependent upon small-scale topographic variation. The mapping has shown that spring phenological events are more advanced in the valleys (except for steep north-facing slopes with low sunshine duration) than in the adjacent landscape. Possible climatic processes underlying this pattern are discussed with special emphasis on temperature inversions in the river valleys. The cold-air-drainage inversions reported from the valleys are probably too infrequent and short to delay phenological events in plants. The combined effects of advanced phenology and the increased risk of spring frost injury due to cold-air-drainage inversions in the valleys are suggested as a possible explanation for some local distributional patterns of flora and vegetation.

Links

• GA206/96/0131, research and development project: Name: Diverzita vegetace a flóry říčních údolí: modelování vlivu abiotických faktorů

Investor: Czech Science Foundation, Diversity patterns of vegetation and flora in the river valleys: environmental control modelling