CLIMATE MONITORING PROTOCOLS

A.T. Finnamore

Provincial Museum of Alberta, 12845 - 102 Avenue, Edmonton, Alberta, Canada T5N 0M6.

Introduction

In order to make meaningful comparisons of arthropod data over time or to correlate changes in arthropod species assemblages with long-term global change it is necessary to monitor climate. Climate variables affecting biodiversity include daily maximum temperature, daily minimum temperature, precipitation, daily heat accumulation, degree days, snow cover, and ice formation and breakup, among others. All of these abiotic variables provide critical information necessary for comparison of biotic data through time. For instance fluctuations in local weather conditions affect arthropod species assemblages and make comparisons between sites or years difficult. Cold weather can delay arthropod development time while hot weather can increase arthropod development time. Degree day accumulation can be used to reduce seasonal bias in comparisons of arthropod species assemblages between sites or between years and provides a better basis for comparisons than does the Julian Calendar.

The International Tundra Experiment ITEX has produced a standard set of climate observations that are monitored at its sites (Molau 1993). ITEX was created as a Man-And-The-Biosphere initiative in 1990, and is an official research project within the MAB Northern Research Network. ITEX is represented in the International Arctic Science Committee and affiliated with Global Change & Terrestrial Ecology, a core program within International Geosphere-Biosphere Programme.

The goal of ITEX is to understand the response of tundra plant species through simple manipulation and transplant experiments to be conducted at multiple arctic and alpine sites. Research is directed at four basic questions:

1. How will the selective environment change as a result of experimental warming?
2. Will experimental warming result in a shift in the selective regime?
3. Are populations of arctic and alpine species able to accommodate warmed climatic conditions over the long term?
4. Is phenotypic variability in warmed and control plots due to environmental effects, genetic variability, or a combination of the two?

ITEX manuals provide detailed instructions on collection and calculation of climate data. Since the climate variables monitored by ITEX are those generally affecting arthropod communities and it since it is desirable to adopt standardized protocols I recommended that climate protocols detailed in the ITEX manual for collection of abiotic data be adopted for the SAGE project. However, soil temperature (at surface, 5 cm and 10 cm) should be added to the ITEX protocols.

The ITEX manuals also provide detailed instructions on construction of plot enclosures that passively modify daily heat accumulation. They vary from 0.5 to about 2m² and are intended to provide information on climate warming in the arctic. As with smithsonian plots intended for woody plants, the disturbance caused in plot establishment and in detailed documentation of the plant community would affect arthropod species assemblages. Additionally the size of most arthropod sampling devices would seriously compromise an ITEX plot. The use of Geographic Information Systems to identify analogous sites permits association of arthropod communities sampled in remote sites with any plots where disturbance is a factor.

Reference

Molau, U. 1993. ITEX Manual. Danish Polar Centre, Copenhagen, 29pp + appendices, tables & protocols.