Epigeic terrestrial invertebrates as indicators of environmental changes on a European scale

Transcription

1 ALARM Field Site Network (FSN) Project of Partner UBern within FSN Epigeic terrestrial invertebrates as indicators of environmental changes on a European scale Ground-dwelling terrestrial arthropods represent an important part of animal biodiversity, both at the landscape and European scale, and contribute to many ecosystem functions such as decomposition and pest control. Predatory taxa such as spiders (Araneae), ground beetles (Coleoptera: Carabidae) and rove beetles (Coleoptera: Staphylinidae) encompass, on a European scale, several thousands of species each. They can easily be collected with standardized methods across a variety of ecosystems. Many studies have shown that these groups are sensitive to environmental change and since their ecology is well known, they proved to be ideal short term and long term monitor organisms suitable as multiplepurpose indicators on large geographic scales. We propose to use these groups as indicators of environmental change on a European scale. To our knowledge this approach has not yet been pursued on a European level. Partner UBern s expertise lies in the taxonomy, ecology and distribution of European spiders, thus we will primarily focus on this taxon. Since our standardized collection methods gather at the same time valuable material of other taxa (such as the beetle families mentioned above), this material could be forwarded to other partners or collaborators specialized on these groups. Methods We will use the ALARM field site network FSN and possibly a few other available field sites. 15 field sites, widely distributed over whole Europe, will enable us to collect material at the same time on a continental scale. At each field site, a natural and a disturbed location will be selected. The ideal natural location is wood or scrubland, as close to the potential vegetation of this area as possible. The ideal disturbed location is an agriculturally used area, best is a field with cereals, and next best is a field with other crops. We will mail parcels with the trap material and preservation liquid to the persons in charge of these field sites (field site manager). An easy-to-follow instruction manual will allow them to set up these traps with little effort and manpower. In the Mediterranean part of Europe we will start in late March / early April, in the northernmost parts probably only in June. The pitfall traps will be dug into the soil and filled with preservation liquid. In the following 2 weeks no maintenance is needed while the traps collect epigeic arthropods. After these 2 weeks, the trap content is emptied into a plastic jar. Now a period of 2 weeks without trapping is included, followed by a second period of collecting. In total 3 periods of collecting epigeic arthropods, each 2 weeks, are interrupted by two 2-week-intervals. Thus, the total time amounts to 10 weeks where the field site management is involved. The parcels, containing jars filled with the trap content will be shipped back to Bern after each period of collection.

2 In Bern we will transfer the collected arthropod material from the preservation liquid into another long-term preservation liquid, and we will perform a coarse pre-sorting of the material into major taxa. Taxa of interest will be forwarded to other collaborators where the final analysis on species level will be performed. Spiders will be analysed in Bern, for Carabidae partners in UK and Germany indicated collaboration, other groups may be analysed via an Austrian partner. The pitfall trap method allows us to collect in a highly standardized manner relevant high-quality data simultaneously across whole Europe. Such a European-wide collection, as it is performed in 2006, may be repeated in a few years to allow tracking a possible response of the analysed communities over time. Results The detailed analysis of spider communities across Europe will allow the following results and interpretations: 1. By species identification: Numbers of species per location, gradients of biodiversity within Europe, centres of biodiversity, changes of biodiversity. 2. By a comparison between disturbed and natural field site: Amount of biodiversity change due to disturbance, within a European gradient. Similarity of spider communities of natural or disturbed sites across Europe. 3. Species identification will also give information on the proportion of native and alien species (approximately 5 % of European species are alien) for natural and disturbed field sites. On a European level this will allow conclusions for the threat to special types of ecosystems and for gradients within Europe. 4. By attributing species to ecological guilds: Differences in guild structure on European level and changes herein. 5. Body size is, among others, temperature dependent. If on a European scale the distribution of body size of spiders can be matched with the annual temperature distribution within Europe, the effects of climate change on spider distribution can be forecasted. Amount of work per field site manager Receiving 3 parcels, shipping them individually back to Switzerland, general organisation 0.25 days Search for suitable locations, preparation time 0.5 days Digging 2 x 8 holes into the soil, filling with preserving liquid. 0.5 days Two weeks later, emptying trap content into jars, traps stay empty days Two weeks later, filling traps again days Two weeks later, emptying trap content into jars, traps stay empty days Two weeks later, filling traps again days Two weeks later, emptying trap content into jars, removal of traps days Estimate of total amount of time investment 2.5 days

3 Field sites We will use 11 field sites of FSN 1. Abisco (Sweden) 2. Cluj (Romania) 3. Estland 4. Göttingen (Germany) 5. Krakow 2 (Poland) 6. Lesbos (Greece) 7. Veneto (Italy) 8. Avignon (France) 9. Berkshire (UK) 10. Toledo (Spain) 11. Uppsala (Sweden) Additional field sites have been mentioned and should be included whenever possible: 12. Doñana (Spain) 13. Lithuania 14. Ile de France (France) 15. Scotland (UK) 16. Bern (Switzerland) Materials needed Each field site manager will receive three parcels each containing: - 2 x 8 plastic pitfall traps (plus some spare ones), 0.1 L volume each - 2 x 8 plastic jars for the preserved trap content, 0.1 L volume each - 2 x 8 lids to close pitfall traps - 1 x 2 L bottle with 1.6 L of conservation fluid to fill the traps - Jar labels and parcel label The first parcel contains an instruction manual, a digging tool and a forceps. After each collecting period of 2 weeks, the respective parcel is shipped back to Bern, this first material arrives in Bern second half of April. Check volume, lids? Deadlines 2006 Early March: FSN Management is informed and agrees to the project. Mid of March: all field station managers are known and informed ( ) Mid of March: Parcel material is ready for shipment End of March: Parcels are at the field sites. End of March/Early April: Mediterranean field sites start with pitfall traps. End of April: first collected material arrives in Bern Early May: Central Europe starts End of May / Early June: Northern Europe starts End of August/early September: last material arrives in Bern.

4 Instruction manual Dear field site manager Thank you very much for cooperating with us within the Field Site Network FSN of the ALARM project. We want to ask you to set up 8 pitfall traps in a natural habitat and 8 pitfall traps in a disturbed habitat. These traps stay for 2 weeks, the content is filled into plastic jars. After 2 weeks of pause, the collecting period is repeated twice, so that there are a total of 3 trapping periods and 2 pauses. We send you all necessary material in 3 parcels, please send each parcel back immediately after you filled the jars with the trap content. So, the time schedule is as follows: 3 parcels received 2 weeks trapping parcel 1 sent back 2 weeks pause 2 weeks trapping parcel 2 sent back 2 weeks pause 2 weeks trapping parcel 3 sent back In case of requests or uncertainty, please contact xxxxxxxxxxx

5 Step by step instruction manual 1. You receive 3 parcels Check the content of each parcel. 8 plastic jars (in plastic bags) for the natural location 8 plastic jars (in plastic bags) for the disturbed location 2 x 8 pitfall traps (plus 8 as reserve) 1 large bottle with preservation fluid and a small bottle with detergent protective gloves measuring cup, funnel Warning The preserving liquid contains 5 % formaldehyde. This is a normal and biodegradable substance but plase be careful and wear the protective gloves when handling it. Avoid contamination or inhalation, wash your hands afterwards. Do not open the bottle inside closed rooms. In case of contamination wash with normal tap water immediately. Eyes, nose and mouth are very sensitive to formaldehyde and should be washed carefully after contamination. Avoid spilling preserving liquid onto the soil around the traps. Waste management: Send us the bottle, where the preserving fluid was in, and all remnants back.

6 Fill the bottle slowly with normal tap water as indicated. After this, add the detergent from the small bottle. Bottle with preservation liquid The first parcel contains a digging tool and a forceps. This digging tool has a similar shape as the plastic beakers used as pitfall traps. Therefore digging the holes is rather easy. 2. Select two locations The natural site Best is forest or scrubland, as close to the potential vegetation of your area as possible.

7 The disturbed site The best disturbed location is an agricultural field with cereals (ideally winter wheat). If this is not available, take a field with another crop, if this is not available select grazed grassland. 3. Set up the pitfall traps (period 1) Place all traps at a standard distance of 20 m from the edge of the habitat. Dig a hole into the soil with the digging tool from parcel 1. Throw soil from this hole more than 3 m apart. The upper border of the traps should be at equal level as the surrounding soil. It is crucial to avoid any projection of the trap edge above the soil surface! Distance to the next trap 3 m. If possible put traps in one line. Avoid dirt in the trap. Fill each trap with 100 ml preserving liquid as indicated. Do not spill preservation liquid onto the soil.

8 4. Wait 2 weeks 5. Empty pitfall traps Empty the content of each pitfall trap into one plastic jar. In case of handling problems, use the forceps. Excess liquid (e.g. after rainfall) can be returned to the bottle and disposed. Per location and date, this yields 8 arthropod samples each in its own jar. Each jar has a label. Put a lid onto the empty pitfall trap to protect it for the next 2 weeks. Protect the 8 jars from one location in one plastic bag. Send parcel 1 back to Bern. parcel to Bern 6. Wait another 2 weeks

9 7. Fill traps again (period 2) Remove lids, check pitfall traps. Replace broken traps. Take preservation liquid from parcel 2 and fill the traps. 8. Wait another 2 weeks 9. Empty pitfall traps Empty the content of one pitfall trap into one plastic jar. Per location this yields 8 filled jars. Each jar has a label. Put a lid (Petri dish) onto the empty pitfall trap to protect it. Protect each 8 jars from one location in one plastic bag. Send parcel 2 back to Bern. 10. Wait another 2 weeks 11. Fill traps again (period 3) Remove lids, check pitfall traps. Replace broken traps. Take preservation liquid from parcel 3 and fill the traps. 12. Wait another 2 weeks 13. Empty pitfall traps Empty the content of one pitfall trap into one plastic jar. Per location this yields 8 filled jars. Each jar has a label. Protect each 8 jars from one location in one plastic bag. Remove pitfall traps. Send parcel 3 back to Bern.

10 14. Make digital photo. If it is possible please make a few digital photos from your investigation: Photo 1: Natural site: landscape Photo 2: Natural site: one trap with surroundings Photo 3: Disturbed habitat: landscape Photo 4: Disturbed habitat one trap with surroundings. You may add a photo showing you at work. Please send these photos per attached to xxxxxxxx Thank you very much for your support