Agricultural and Food Science in Finland, Vol. 10 (2001): 261–276 261 A G R I C U L T U R A L A N D F O O D S C I E N C E I N F I N L A N D Vol. 10 (2001): 261–276. © Agricultural and Food Science in Finland Manuscript received May 2001 A G R I C U L T U R A L A N D F O O D S C I E N C E I N F I N L A N D Vol. 10 (2001): 261–276. Ground beetle (Coleoptera, Carabidae) diversity in Finnish arable land Juha Helenius Department of Applied Biology, PO Box 27, FIN-00014 University of Helsinki, Finland, e-mail: juha.helenius@helsinki.fi Jarmo K. Holopainen MTT Agrifood Research Finland, Plant Production Research, Plant Protection, FIN-31600 Jokioinen, Finland. Current address: Department of Ecology and Environmental Science, University of Kuopio, PO Box 1627, FIN-70211 Kuopio, Finland Erja Huusela-Veistola MTT Agrifood Research Finland, Plant Production Research, Plant Protection, FIN-31600 Jokioinen, Finland Sirpa Kurppa MTT Agrifood Research Finland, Plant Production Research, Plant Protection, FIN-31600 Jokioinen, Finland. Current address: MTT Agrifood Research Finland, Environmental Research, FIN-31600 Jokioinen, Finland Pia Pokki, Anna-Liisa Varis Department of Applied Biology, PO Box 27, FIN-00014 University of Helsinki, Finland Carabid data compiled from six independent studies, consisting of 97 799 individuals trapped by pitfalls from Finnish agricultural fields and identified to 111 species were analyzed. Shannon-Wiener H’ diversity index was typically around 2.5 and expected species number rarefied to 600 trapped individuals was typically around 30 species. The five most abundant species accounted for 42% of the total catch, and the thirty most abundant species made up 98% of the total catch. Percentage similarities among the assemblages by PS-index were from 16% to 48%. In comparison to published data about carabid diversity in boreal forests, which form the dominating habitat matrix in which Finnish farmland is embedded as relatively small patches, arable fields harbor more species rich assemblages, with more even rank-abundance distributions but variable species composition. Impor- tance of landscape (regional) level, instead of spatial level of crop fields, in understanding carabid diversity in farmland is discussed. Inclusion of carabids into monitoring schemes of agro-biodiversi- ty at landscape level is suggested. Key words: Carabid fauna, agricultural fields, species richness, evenness, similarity, agro-biodiversi- ty, monitoring mailto: juha.helenius@helsinki.fi 262 A G R I C U L T U R A L A N D F O O D S C I E N C E I N F I N L A N D Helenius, J. et al. Ground beetle diversity Introduction Ground beetles (Coleoptera, Carabidae) are ground dwelling, polyphagous or predatory in- sects, abundant in many kinds of terrestrial hab- itats. The larvae are subterranean predators. Carabids may be collected in large numbers us- ing pitfall traps, and due to their abundance and species richness (more than 40 000 species de- scribed) they are popular objects of study. They are abundant in agricultural fields all over the world and may be important natural enemies of agricultural pests. Thiele (1977) investigated the carabids associated with European agricultural crops. For Fennoscandia and Denmark, a com- prehensive key for identification, with short de- scriptions of biology, is available from Lindroth (1985, 1986). Our aim is not to present a review of the extensive literature of agro-carabidology. Among many excellent reviews, see e.g. Lövei and Sunderland (1996), or Kromp (1999). In 1956, Wishart et al. estimated that preda- tory beetles destroyed 70% of cabbage root fly eggs, and Hughes (1959) confirmed that cara- bids were mainly responsible for this. Potts and Vickerman (1974) suggested that polyphagous predators such as carabids (but also some rove beetles (Staphylinidae) and many spiders) are important predators of aphids in cereal ecosys- tems. In decades following these reports, applied research into the role of carabids in agroecosys- tems has proliferated. Kromp (1999) concludes his review on this aspect by asking for more stud- ies that would quantify predation and pest con- trol in open-field conditions, and emphasizing that carabids are only one component in the nat- ural enemy complexes in crop fields. Most of the studies from which our data originates were originally motivated by the beneficial role of carabids. In Finland, Varis and colleagues initiated agro-carabidology by studying egg predation on cabbage root flies (Varis 1982), and abundance and seasonal occurrence of adult carabids in some crops in southern Finland (Varis et al. 1984). She and her students then continued with studies on various applied aspects: studies on trapping methods (Holopainen and Varis 1986, Holopainen 1992), on predation of root flies (Varis 1989) and cereal aphids (Helenius 1990, Holopainen and Helenius 1992), on abundance and reproduction (Helenius et al. 1995, Helenius 1995), and on pollution effects (Holopainen et al. 1995) in agroecosystems. Vasarainen and Kurppa (1996) and Huusela-Veistola (1996, 2000) continued with studies into effects of cul- tivation techniques and pesticide use on carabids. All these studies serve in describing carabid di- versity, but Kinnunen (1999, see also Kinnunen et al. 1996, Kinnunen and Tiainen 1999, Kin- nunen et al. 2001) was the first who focused into understanding the patterns, especially in relation to spatial scales, in communities of carabids in Finnish farmland. Apart from what is listed above, we do not know of other studies that would deal with di- versity of carabids in agricultural fields in Fin- land. As only 9% of the land cover is in agricul- tural use, and practically all the rest is under for- est cover, Finnish biologists have traditionally focused into forest systems. However, Kin- nunen’s (1999) work now provides a landmark for further studies on community ecological as- pects of carabid diversity in agricultural land in Finland. In this report we do not aim into a communi- ty ecological analysis. The basic idea of this study was to pull together our various pitfall data on carabids in many regions and over a 17 years time span in Finnish agroecosystems, in order to provide a reference for future surveys of spe- cies diversity (along the lines of Duelli et al. 1999). We believe that such reference, even if unperfected in many respects, may be useful es- pecially for future studies monitoring biodiver- sity and agroecosystem change in Finland. 263 A G R I C U L T U R A L A N D F O O D S C I E N C E I N F I N L A N D Vol. 10 (2001): 261–276. Material and methods Study areas, data sets and trapping methods All data were from pitfall trapping studies. Al- together 23 subsets of data from 1978 until 1994 were used, and the pooled (total) number of pit- fall samples was 21344. These studies covered a geographic area ranging from the Southwest to the Northeast of Finland (Table 1, Fig. 1). Regional range is from hemiboreal to southern boreal phytogeographical zones (Ahti et al. 1968) and from 1.25 to 0.95 k°C DD above 5°C in the length of the thermal growing season. Pitfall traps varied moderately in design (Ta- ble 2). All studies used circular cups, in which the diameter range was 80 to 100 mm. The most common collecting fluid was water with deter- gent and sometimes NaCl as preservative add- ed. In one study, ethylene glycol, and in anoth- er, formalin solution was used. A lid to shade the trap was sometimes used (Table 2). Traps Table 1. Data sets and study sites (from North to South, see also Fig. 1). Windows of Day Degrees are indicated, and the total catch of carabids given, for the sub-sets of the data. Data set Author Year Trapping period DD range1 Total number of specimens Siilinjärvi Holopainen 1991 4 June – 20 August 74.3 – 876.9 8722 Outokumpu Pokki 1990 9 May – 20 July 76.3 – 580.6 3062 1991 15 May – 21 July 20.2 – 556.7 2315 1993 12 May – 1 July 87.7 – 375.0 1057 1994 18 May – 39 June 66.0 – 322.2 726 Total . 20.2 – 580.6 7160 Jokioinen Kurppa 1991 31 May – 24 September 66.7 –1087.5 2442 1992 5 May – 26 August 18.8 –1106.9 3666 1993 7 May – 1 September 102.2 –1076.2 3018 1994 6 May – 25 August 51.0 –1047.3 1534 Total . 18.8 –1106.9 10660 SW Finland Huusela-Veistola 1991 17 June – 5 July 81.9 – 510.9 11860 Viikki-I Helenius 1983 26 May – 21 July 132.3 – 792.4 5675 1984 18 May – 20 July 58.3 – 757.4 3703 1985 30 May – 5 September 66.5 –1160.3 1102 1986 29 May – 7 August 189.4 –1040.7 2595 1988 13 May – 22 September 52.3 –1533.8 2812 1989 23 May – 19 June 152.6 – 394.5 555 1990 9 May – 16 September 144.1 –1320.9 11346 1991 13 May – 4 August 40.7 – 807.7 8551 Total . 40.7 –1533.8 36339 Viikki-II Varis 1978 17 May – 14 September 29.4 –1195.5 8348 1979 10 May – 12 September 8.1 –1362.4 9170 1982 31 May – 20 August 134.0 – 982.7 5633 1984 11 June – 26 July 359.4 – 815.1 570 1985 2 June – 27 July 160.6 – 715.8 997 Total . 8.1 –1362.4 24718 Total . . . 99459 1 Range of Day Degrees accumulated from the start to end of the trapping period, obtained from the nearest meteorological station as accumulation of degrees above 5°C from the onset of the thermal growing season. 264 A G R I C U L T U R A L A N D F O O D S C I E N C E I N F I N L A N D Helenius, J. et al. Ground beetle diversity were emptied at intervals of two days to two weeks. Trapping effort is expressed as the total number of trap-days cumulated from the onset to the emptying of the last trap for each of the data sets (Table 2). The Siilinjärvi data (63°03’ N, 27°39’ E) are from the study by Holopainen et al. (1995) who conducted pitfall trapping from 15 spring bar- ley fields and one oat field in the Siilinjärvi municipality. The original aim in this study was to relate carabid diversity to soil properties and to foliar fluoride content. Holopainen (1992) described details of the trapping method, and an independent analysis of species diversity was given by Holopainen et al. (1995). The 1990–1991 subset of Outokumpu data are from an unpublished M.Sc. study by Pokki (Pia Pokki, unpublished MSc thesis, University of Helsinki 1992), which aimed to describe the local diversity of carabids in arable land. Pit- fall trapping was conducted in 8 spring barley fields in the neighboring municipalities of Ou- tokumpu (3 fields; 62°42’ N, 29°05’ E), Liperi (2 fields; 62°36’ N, 29°14’ E), Joensuu (one field; 62°36’ N, 29°34’ E), and Kontiolahti (2 fields, 62°45’ N, 29°49’ E). In each field, three trap sta- tions of two traps 2 m apart were established at 30 m intervals. The 1993–1994 subset of Outo- kumpu data is from an unpublished study by Pokki and Helenius, in which the effect on cara- bid activity-density of undersowing with clover or ryegrass was investigated. Trapping was con- ducted in spring barley fields in Outokumpu (4 fields) and in Liperi (4 fields). The trapping method was the same as for the 1990–1991 Ou- tokumpu data. The Jokioinen data are from a study by Kurp- pa and Vasarainen (Vasarainen and Kurppa 1996), in which activity densities of carabids were compared between various crop rotations and between organic and conventional produc- tion. All the data are from Yöni-farm in Jokioi- nen (60°48’ N, 23°28’ E), from 14 fields. In these fields, according to the crop rotation scheme, the crops were spring barley (either with or without next year’s ley undersown), winter rye, an oat- pea mixture (traditional ‘mixed cereal’), ley, open fallow, or a weedy field uncultivated since the late 1980s. In the middle of each field, five pitfall traps in 10 m intervals were emptied eve- ry two weeks. The SW-Finland data are from an unpub- lished study by Kurppa and Huusela-Veistola. In this study, 127 arable farms in around South and Southwest of Finland were sampled, and pitfall trapping conducted in cereal fields on 43 farms, in sugar beet fields on 49 farms, and in spring rape fields on 35 farms (Fig. 1). Each field was sampled by 10 traps. These were in two sets of five traps, each of the five at 10 m intervals in a row. The traps were run for a two week period. The trapping periods were set to weeks 23 to 25 in cereal fields, 25 to 27 in sugar beet fields and to weeks 26 to 28 in spring rape fields. The Viikki-I data are from studies on epigeal predators (Helenius 1990) in spring-sown cere- al or seed legume crops on Viikki Experimental Fig. 1. Map of sampling locations for the six data sets of the study. 265 A G R I C U L T U R A L A N D F O O D S C I E N C E I N F I N L A N D Vol. 10 (2001): 261–276. Farm (60°13’ N, 25°02’ E) in Helsinki. For sum- maries see Helenius (1991a). In the 1983 exper- iment, the crops were oats, an oat-faba bean mix- ture and faba bean alone, in which pitfall trap- ping was conducted in 8 plots, with 16 traps per plot. Half of the traps were operated within 5 m × 5 m enclosures, enclosed by steel strip 200 mm high, buried 50 mm into the soil (see Helenius 1990). In the 1984 experiment, the crops were also monocrops or mixtures of oats and faba bean. Pitfall trapping was conducted in 24 plots, one trap per plot. One half of the traps were op- erated within egress-only plots, and the other half within plots surrounded by ingress-only trench- es (ca. 8 cm deep trenches, Helenius 1990). In the 1985 experiment, the crops were oats and an oat-faba bean mixture. Trapping was con- ducted in 12 plots, 2 traps per plot. A quarter of the traps were in open plots, another quarter in plots enclosed by an egress-only trench (trench- es as in 1984) for the whole period, a further quarter in plots enclosed by egress-only trench- es until June 24, and the rest in plots trenched after June 24. In the 1986 experiment, the crops were oats and an oat-faba bean mixture, and the trapping was conducted in 12 plots, 2 traps per plot as in 1985. Half of the traps were operated within isolators 57 cm in diameter, 30 cm high, buried 20 cm deep into the soil, covered with an insect net (see Helenius 1991b for description and for some results from oats). In the 1988 to 1991 experiment, one hectare of spring barley, as a monocrop or undersown with ryegrass or clover (1988 to 1991), or spring wheat, was used for studying the possibility of enhancement of carabids by undersowing in ce- Table 2. Details of pitfall trapping. Data set Year Effort Diameter Collecting fluid Lid on trap (trap-days) (mm) Siilinjärvi 1991 1155 90 water+detergent Aluminium Outokumpu 1990 3108 100 water+detergent+salt no 1991 2814 “ “ “ 1993 2016 “ “ “ 1994 1692 “ “ “ Jokioinen 1991 5060 “ water+detergent+salt Plastic foil 1992 6335 “ “ “ 1993 6055 “ “ “ 1994 5590 “ “ “ SW Finland 1991 17780 95 “ “ Viikki-I 1983 8064 80 water+detergent no 1984 1608 “ “ “ 1985 720 68 50% ethylene glycol “ 1986 1680 80 water+detergent no 1988 4848 100 “ “ 1989 800 “ water+detergent+salt no 1990 3808 “ “ no 1991 1664 “ “ no Viikki-II 1978 7680 80 dry / 2% formalin+det. Plastic foil 1979 4000 “ “ “ 1982 2916 “ water+detergent no 1984 1104 “ “ “ 1985 1320 “ “ “ Total 91817 trap days 266 A G R I C U L T U R A L A N D F O O D S C I E N C E I N F I N L A N D Helenius, J. et al. Ground beetle diversity reals (Holopainen and Helenius 1992, Helenius and Tolonen 1994, Helenius 1995, Helenius et al. 1995). Altogether, 48 traps in 1988, 32 traps in 1989 (half of which were within plots of 2 m × 3 m enclosed by plastic sheet, 10 cm high, buried 2 cm into the soil), and 32 traps in 1990 and 1991 were operated. The Viikki-II data of 1978 and 1979 are from a faunistic study by Varis et al. (1984) and by Holopainen and Varis (1986). One cabbage field, one sugar beet field, and one timothy field in Viikki Experimental Farm were included. Each field was sampled by 64 traps (4 × 16 trap set) in 1978 and by 32 traps (4 × 8 trap set) in 1979. Every fourth trap was filled with a formalin medium; otherwise dry traps were used. The traps were emptied every two to four days. Half of the traps were operated inside 10 m × 10 m plots (16 traps per plot in 1978 and 8 traps per plot in 1979) surrounded by 35 cm high and 15 cm deep plastic barriers in order to restrict the movement of carabids into and from the plots (for details, see Varis et al. 1984, and Holopain- en and Varis 1986). The Viikki-II data of 1982, 1984 and 1985 are from studies by Varis and Tolonen (unpub- lished M.Sc. thesis by Timo Tolonen, Universi- ty of Helsinki 1990), in which carabids were studied as predators of cabbage root flies in Viikki Experimental Farm. The crops were monocropped white cabbage or white cabbage undersown with subterranean clover. The cara- bids were trapped in 1982 in 6 plots, and in the other years in 4 plots by 6 traps per plot. In 1984 and 1985 half of the traps were within enclo- sures of steel strips 10 cm high, 5 cm deep into soil. Identification of species Identification keys by Lindroth (1985, 1986) were used, and the nomenclature follows the enumeration by Silfverberg (1992). Only adult specimens were included. The members of the research teams did taxonomic work. Coleoptera specialists were consulted in a few unclear cas- es. For the Jokioinen data, specimens of the ge- nus Amara were not identified to species level, and for the SW Finland data, only A. aulica, A. eurynota and A. plebeja were identified to spe- cies level. Authors of the scientific names of the species are given in Appendix 1. Meteorological data Cumulative day degrees (DD, in °C above 5°C) were calculated as thermal windows of trapping (Table 1). By definition (Finnish Meteorologi- cal Institute) the accumulation of DD starts in spring as the mean daily temperature at 2 m height above ground is permanently above 5°C, and the snow cover is less than 50%. We used the standard DD statistics from the Finnish Me- teorological Institute. The DD data for each pit- fall study was obtained from a meteorological station closest to the site. The stations do not measure heat sums at ground level, which would be more directly interpreted as conditions expe- rienced by the carabids. However, the thermal windows are better related to phenology of poikilotherms than calendar dates, especially for comparison of sites latitudinally far from each other (e.g. snow melts a month later in the most northern sites than in the most southern sites). Data analysis The data are from several independent studies, with variable pitfall trapping methods, in varia- ble crops and 14 variable growing seasons in several widely distributed locations. Each of these factors is confounded with all or many of the other factors. From the first to the last study, a period of 17 years is covered. No assumptions are made concerning possible trends in diversi- ty during this time. As a consequence of this heterogeneity, the data are used only to obtain an overall picture of the diversity of ground bee- tles in Finnish arable land, rather than to attempt to deepen our understanding about their ecolo- gy and function in agroecosystems. 267 A G R I C U L T U R A L A N D F O O D S C I E N C E I N F I N L A N D Vol. 10 (2001): 261–276. Ranks of the species abundances were cal- culated as means over the relative (%) catches in the six data sets. Among the top 30 species in rank abundance, rank frequencies were com- pared. These were calculated as ranks in the in- cidence, or occurrence in the samples of the pooled data. For further comparison, abundance ranks based on total catch of the species in the pooled data were also calculated. Estimate of Gamma (γ) diversity is the total number of spe- cies caught (S). Shannon-Wiener H’ (see Southwood 1978) was used as a robust and general Alpha (α) di- versity index for the local assemblages represent- ed by the six sets of data: (1) H’ = Σp i lnp i , where p i is N i /N (N stands for total catch of in- dividuals) for species i. H’ was calculated in three different ways, first with Amara-specimens identified to species level, then with Amara ex- cluded, and finally, with Amara sp. at genus lev- el. The last two allowed calculation of the index also for the Jokioinen and the SW Finland data sets. Interpretation of H’ in this study must be done bearing in mind that the ‘local assemblage’ refers to ground beetle communities sampled in each of the individual studies. Thus, due to pool- ing in each of the data sets, H’s do not refer to ecologically meaningful entities (which would be assemblages, or communities, at the same time in the same site). Evenness associated to H’, was calculated as J’ (= H’/lnS). Rarefaction (Simberloff 1978, see also Kou- ki and Haila 1985, Duelli et al. 1999) was used to further study the structure of the assemblages: this method models how species are accumulat- ed with increasing number of individuals caught in the trapping. For any sample size (n) smaller than the original sample N (n < N), the expected number of species E(S n ) is calculated as: where N i is the number of individuals of species i in the original sample. It should be noted that neither rarefaction curves nor H’ use identities of species: in an extreme case, two samples rar- efied to the same number of individuals may have the same number of species, but none of the same species. Similarly, two samples may have the same H’, without sharing the same spe- cies. For comparison of similarities between the different data sets at the level of species’ identi- ties, two Beta (β) diversity indices were calcu- lated (Wolda 1981). Jaccard index is indicative of similarity of the species lists only, ignoring the evenness component. Thus, this index is sen- sitive to species numbers, to the chance event of getting a high number of low frequency species in the catch: (3) Cj = j/(a + b–j) where j is the number of species common to the two samples, and a and b are respectively the total number of species in each sample (South- wood 1978). The other index, Czekanowski-Sø- rensen-Renkonen’s (subsequently referred to as Renkonen’s index) percentage similarity PS is not dependent on species numbers, being sensi- tive to the evenness component of α-diversity: (4) PS = Σ min(p 1i , p 2i ) where p i is the proportion of the species i in the total catch in data sets 1 and 2 (Wolda 1981). For all the diversity indices, Viikki I data were sorted to exclude samples from the plots in which beetle movement had been experimentally ma- nipulated, giving 62 species from a catch of 31934 specimens in this sub sample. This pre- caution reduced the estimated value of H’, for example, by only 0.01 to 0.02 units. Cj and PS were also calculated from sub-sets of data within the same thermal window of DD- range 20.2–580.6°C, set by the narrowest win- dow of the data sets, that of Outokumpu. This was done in order to allow phenologically more realistic comparison than the comparisons be- E(S n ) = Σ 1– S i =1 N – N i n( ) N n( ){ }(2) 268 A G R I C U L T U R A L A N D F O O D S C I E N C E I N F I N L A N D Helenius, J. et al. Ground beetle diversity tween the original data sets with variable trap- ping times and variable thermal periods. Results Altogether, 111 species of Carabidae were iden- tified from the total of 97799 specimens deter- mined to species level, in the total catch of 99459 beetles (Table 3, Appendix 1). This gives an av- erage catch rate of 1.08 ground beetles per trap day. Order of H’ values were not sensitive to the inclusion or exclusion of Amara sp. at the genus level. The values of H’ ranged from 2.32 to 2.97 in the three data sets with all species identified (Table 3). The highest alpha-diversity H’, but with relatively low evenness J’ values, were from cabbage and sugar beet crops of Viikki II data (Table 3). Number of species in the data sets ranged from 45 to 82. As a cautious, conservative rule of thumb (in judging from the rarefaction curves), Finnish crop fields typically harbor cara- bid communities of at least 30 to 40 species. Rarefied to sample size of 600 individuals (which is sufficiently small sample to include all our data sets), expected species number was in every case over 20 species (Fig. 2). Expected species number at 600 individuals in northern (Outokumpu) barley crops was 31 and 32 spe- cies, 5 and 9 species more than in southern (Viik- ki) barley crops in 1990 and 1991, respectively (Table 4, Fig. 2a–b). With this sampling effort, highest expected species number was found from Viikki cabbage and sugar beet (Fig. 2c) crops in 1978 and 1979 (Table 4). The five most abundant species accounted for 41.96% of the total catch in the pooled data Table 3. Number of Carabidae species, number of identified specimens, total catch, α-diversity index H’, and evenness index (J’). Because for two of the data sets (Jokioinen and SW Finland), no data of Amara at species level were available, H’ and J’ are calculated in three versions: first, with Amara species included, then by excluding the genus, and last, by includ- ing the genus. (The data sets are in approximate order from North to South: Siilinjärvi-Outokumpu-Jokioinen-SW Finland- Viikki I-Viikki II.) Summary statistics Data set Total Sii Out Jok S-W Fi Viik-I Viik-II Number of species 45 51 n.a. n.a. 65 82 111 (excluding Amara species) (33) (39) (27) (39) (47) (61) (84) No. of specimens identified to species 8722 7160 9844 11453 35908 24712 97799 Total catch 8722 7160 10660 11860 36339 24718 99459 Shannon-Wiener H’ (and J’ for row 1.) 1. with Amara identified 2.32 2.67 n.a. n.a. 2.53 2.97 . (evenness J’) (0.34) (0.37) n.a. n.a. (0.31) (0.33) 2. with Amara excluded 2.28 2.57 2.41 2.59 2.40 2.77 . 3. with Amara at genus level 2.30 2.62 2.53 2.67 2.49 2.78 . Table 4. Expected number of species E(S) of carabids rare- fied to sample size of 600 individuals. Examples from north- ern and southern spring cereal fields, and southern row crop fields. (SD standard deviation) Sub-set of data field crop E(S) SD Outokumpu 1990 barley 30.6 2.12 Outokumpu 1991 barley 32.2 2.11 Viikki I 1990 barley 25.6 1.78 Viikki I 1991 barley 23.2 1.86 Viikki II 1978 cabbage 34.8 1.84 Viikki II 1979 cabbage 33.9 2.12 Viikki II 1978 sugar beet 37.7 1.82 Viikki II 1979 sugar beet 29.2 1.15 269 A G R I C U L T U R A L A N D F O O D S C I E N C E I N F I N L A N D Vol. 10 (2001): 261–276. Fig. 2. Expected (rarefied) species number against number of individuals caught in pitfalls in Outokumpu and Viikki I spring barley crops (solid line 1990, dashed line 1991), and in Viikki II sugar beet (solid line 1978, dashed line 1979). (The middle line is the mean, and the upper and lower lines are + and – SD, respectively). 270 A G R I C U L T U R A L A N D F O O D S C I E N C E I N F I N L A N D Helenius, J. et al. Ground beetle diversity (Fig. 3). These were, in terms of means of the relative catch over the data sets, in rank order Pterostichus melanarius, Clivina fossor, Bembid- ion guttula, Patrobus atrorufus, and Pterostichus cupreus (Table 5). Trechus secalis and T. discus ranked among the top five in abundance in the pooled data, but not quite in terms of mean rela- tive abundance. They were numerous in the large data set (high total catch) of Viikki I. These spe- cies were all included in the list of only 17 spe- cies that were shared by all the data sets. The 17 species (numbered 1–10, 12–15, 19–21, 23 in Table 5) were also among the thirty most abun- dant species. Among the top 30 species, two spe- cies were present in the two northern data sets only. These were Carabus cancellatus and Agon- um muelleri. Another two species were missing from both northern data sets: these were Trechus micros and Acupalpus meridianus. Top 30 spe- cies made up 97.86% of the total catch (Table 5, Fig. 3). The most frequently collected species was C. fossor (Table 5), which was found in 11.7% of samples of the pooled data. The ranks in fre- quencies roughly followed the ranks in mean relative abundance (Fig. 4). Notably more fre- quent than numerous, i.e. common but not abun- dant species within the top 30 were Harpalus rufipes and T. micros. Among the numerous but not as frequent species were P. atrorufus, P. cu- preus, P. niger, B. bruxellense, B. gilvipes, Agon- um muelleri and P. crenatus, in order of rank in abundance (Fig. 4). Percentage similarities (PS) of the species assemblages ranged from 48.4% between the two Viikki data sets, to only 16.4% between the northern Siilinjärvi data from cereals and the very southern (coastal) Viikki II data including row crops. Jaccard’s Cj of similarity between species lists varied less, and ranged from 0.39 between the previous two data sets, to 0.55 be- tween the two northern sets from cereals, name- ly Siilinjärvi and Outokumpu. Notably, as for PS, Cj was also high between the two Viikki data sets (Table 6). Positive correlation between Cj and PS was weak (R2 = 0.54, P = 0.095). Pheno- logically more realistic comparison (subsets of data from the same early season thermal win- Fig. 3. Relative abundance (% in catch), as mean of the proportions of total catches in pitfalls over the six data sets, against rank in the mean relative abundance. (Thirty most abundant species. Error bars: SE). 271 A G R I C U L T U R A L A N D F O O D S C I E N C E I N F I N L A N D Vol. 10 (2001): 261–276. Table 5. Thirty most abundant species numbered in rank order of mean relative pitfall catch calculated over the data sets (first two columns, see also Fig. 3). Ranks in the data sets (in approximate order from north to south) Siilinjärvi-Outo- kumpu-Jokioinen-SW Finland-Viikki I-Viikki II, and mean over these ranks (nc stands for ‘not caught’, i.e. absent from the data set) (middle columns). Species’ share in the total catch (pooled data) and rank in this share (two columns next to the last column). Ranks in frequency (presence-absence) in pitfall samples at level of the pooled data (last column). Note: Amara sp. at genus level, due to incomplete data of species in two of the subsets of data (Jokioinen and SW Finland). Top 30 species in rank order of Abundance ranks in Total catch: Ranks in mean relative abundance the data sets mean rank % rank frequency 1. Pterostichus melanarius 2-4-3-2-1-10 3.7 13.38 1. 3. 2. Clivina fossor 6-1-11-1-3-2 4.0 12.64 2. 1. 3. Bembidion guttula 11-6-2-4-4-36 10.5 6.74 5. 4. 4. Patrobus atrorufus 1-7-14-3-14-12 8.5 4.90 7. 11. 5. Pterostichus cupreus 4-5-1-7-22-46 14.2 4.30 10. 15. 6. Bembidion quadrimaculatum 15-3-9-6-10-7 8.3 4.84 8. 7. 7. Trechus secalis 14-22-8-5-5-3 9.5 7.27 3. 5. 8. Amara sp.* 16-11-5-10-7-1 8.3 6.61 6. 2. 9. Pterostichus niger 3-21-6-9-15-22 12.7 3.23 12. 16. 10. Trechus discus 8-20-19-13-2-19 13.5 7.10 4. 8. 11. Bembidion bruxellense 5-2-nc-14-29-24 . 1.65 16. 20. 12. Harpalus rufipes 23-18-13-11-6-6 12.3 4.56 9. 6. 13. Bembidion properans 28-12-21-21-8-4 15.7 4.08 11. 10. 14. Trechus quadristriatus 21-34-7-15-9-8 15.7 2.82 14. 9. 15. Bembidion lampros 17-10-15-8-16-9 12.5 2.04 15. 13. 16. Calathus melanocephalus 27-28-nc-23-13-5 . 2.88 13. 12. 17. Bembidion gilvipes nc-24-4-18-nc-41 . 1.08 20. 25. 18. Carabus cancellatus 7-9-nc-nc-nc-nc . 0.63 23. 22. 19. Harpalus affinis 25-17-17-12-17-13 16.8 1.15 18. 18. 20. Loricera pilicornis 13-13-12-20-18-16 15.3 0.84 21. 19. 21. Synuchus vivalis 10-30-24-17-11-18 18.3 1.39 17. 17. 22. Dyschirius globosus nc-8-26-24-25-35 . 0.38 25. 23. 23. Pterostichus strenuus 19-15-10-16-35-30 20.8 0.45 24. 24. 24. Trechus micros nc-nc-22-19-12-17 . 1.12 19. 14. 25. Agonum muelleri 9-16-nc-nc-nc-nc . 0.30 28. 34. 26. Calathus erratus nc-35-28-28-19-11 . 0.70 22. 21. 27. Asaphidion flavipes 30-14-nc-27-29-46 . 0.14 35. 28. 28. Pterostichus crenatus 12-19-nc-25-26-46 . 0.16 31. 35. 29. Acupalpus meridianus nc-nc-nc-34-24-14 . 0.35 26. 30. 30. Carabus granulatus 24-30-15-nc-38-41 . 0.14 34. 29. Total 97.86% * of which the most abundant: Amara bifrons 42.79 A. apricaria 9.18 A. plebeja 5.17 A. communis 3.96 A. aulica 3.64 A. municipalis 2.69 In all from total of Amara sp. 67.42% 272 A G R I C U L T U R A L A N D F O O D S C I E N C E I N F I N L A N D Helenius, J. et al. Ground beetle diversity dow defined by DD sums) increased PS values by a mean of 4.6%-units (SD 0.85), and Cj val- ues by 0.04 (SD 0.03) (Table 6), but did not change the order in the comparison. Discussion For a reliable diversity estimate, sampling should access all species equally and in proportion of their population densities. Pitfall trapping meas- ures a combination of density and activity of the individuals, and even trappability may vary be- tween species and be sensitive to slight modifi- cations of the trap design (see e.g. Greenslade 1964, Holopainen 1992, Sundarland et al. 1995). On the other hand, pitfall trapping is cheap and effective in collecting large numbers over short periods of time. Most importantly, pitfall trap- ping is by far the most frequently used method in even ecological studies of ground beetles (Kromp 1999), its shortcomings are known, and in many cases, activity density is exactly what is needed, especially for studies concerning func- Fig. 4. Rank in frequency (occurrence or incidence in samples) against rank in mean relative abundance of the thirty most abundant species in the pooled data. (Species’ order as in Fig. 3, and in Table 5.) Table 6. Similarity (beta-diversity) indices of Jaccard (Cj: above the diagonal) and Renkonen (PS-%: be- low the diagonal) for the data sets (including only the sets for which all the specimens, including Amara sp., were identified to species level). For a phenologically adjusted comparison, index values are also given for early season sub-sets of data set by Outokumpu day-degree (DD) window (in parentheses: in- cluding catches at DD range 20.2–580.6) Data set: Siilinjärvi Outokumpu Viikki I Viikki II Siilinjärvi ------------- 0.55 0.40 0.39 Outokumpu 44.3 ------------- 0.44 (0.45) 0.39 (0.46) Viikki I 35.7 44.2 (48.2) ------------- 0.54 (0.58) Viikki II 16.4 33.7 (39.1) 48.4 (52.7) ------------- 273 A G R I C U L T U R A L A N D F O O D S C I E N C E I N F I N L A N D Vol. 10 (2001): 261–276. tional diversity of this family. In estimating spi- der diversity by four different methods, Codding- ton et al. (1996) found that each method collect- ed clearly different set of species. Future stud- ies of carabid diversity would benefit from such a comparison of sampling methods. Here, we discuss our results keeping in mind that the esti- mates are specific to pitfall sampling. Our estimate of regional (or Gamma) diver- sity of farmland carabids in Finland was 111 species. Six more species would be added from a total pitfall sample of 36675 beetles from farm- land around Lammi Biological Station in south- ern Finland in 1991–1996, analyzed by Kinnunen et al. (1996, 2001), and Kinnunen and Tiainen (1999). The 117 species is 40% of carabid spe- cies found in Finland, including forests and all other habitats (Lindroth 1985, 1986). The alpha-diversities calculated from our data (from pooled samples) do not refer to gen- uine local communities in one place and time. However, the H’ values may be used as rough indices of richness and evenness of the assem- blages sampled. We present these in order to al- low comparison to possible further monitoring studies, which may conveniently be based on meta-analysis of several data sets, as in this study. Using rarefaction, we came up with an esti- mate of at least 30 to 40 species in an ordinary agricultural field in Finland. This would include all species from the early season ones (adult overwinterers) to late season ones (larval over- winterers). Duelli et al. (1999), using sophisti- cated extrapolation from rarefaction curves, re- port estimates of 37.9 ± 5.6 (SD) and 43.1 ± 6.8 species in winter wheat and maize in Switzer- land. They sampled by funnel-type pitfalls, which are more efficient than cup type ones (Obrist and Duelli 1996). Their estimates as well as the rarefaction curves they present are remark- ably close to the ones we report here. We con- sider these estimates being conservative rather than liberal. Exhaustive sampling would result in higher estimates: Kinnunen et al. (Heidi Kin- nunen, Seppo Rekolainen and Maximillian Posch, manuscript: see Kinnunen 1999) trapped 18724 carabid beetles with 900 pitfalls in 45 days in a one hectare plot within a bare fallow field, and caught 60 species. Boreal coniferous forests dominate Finnish landscapes. Fields are embedded in the taiga. In comparison to rarefaction curves for carabid beetle assemblages in the southern Finnish taiga, provided by Niemelä et al. (1990), the curves for the assemblages in the agricultural fields in- dicate more species rich and more even commu- nities. For a sample of 100 individuals from a forest community, ca. 10 species were found (Niemelä et al. 1990), whereas in our samples from agricultural land, the same effort would yield twice as many species. Rarefied species number for 600 individuals ranged from 16.6 ± 0.5 species to 20.6 ± 0.6 species in forests (Niemelä et al. 1990), again almost only half of the values in our data. Why should agricultural fields have higher diversity than successionally mature, relatively stable and undisturbed forests? Although the analysis is outside the scope of this paper, we suggest the contemporary disturbance (non-equilibrium) theory to be applicable. It ex- plains how richness may peak at intermediate level of disturbance frequency (Bagon et al. 1996, p. 813–827, 908–912 and references there- in. See also Pachepsky et al. 2001). Agricultural fields are not in a succession and they are pre- dictable habitats. Although ‘disturbed’, the dis- turbance pattern is rather stable irrespective of crop rotation (‘same procedure as last year’, con- cerning ploughing, sowing etc.). Percentage similarities measured by Renko- nen PS among the data sets were in every case lower (always less than 50%) than those report- ed from forest communities (usually 50% or higher: Niemelä et al. 1990). Assemblages are more variable in fields than in forests. This is in agreement with Kinnunen (1999, p. 10), who concludes: “In forests (…) communities of near- by sites were very similar. The fields instead seem to support less predictable communities.” Again, the disturbance theory provides a way to under- stand the pattern. Communities of carabids in surrounding for- est patches provide a source of immigrants into 274 A G R I C U L T U R A L A N D F O O D S C I E N C E I N F I N L A N D Helenius, J. et al. Ground beetle diversity fields. 24 (70.6%) of the 34 species found by Niemelä et al. (1990) were also included in our list. Effect of drawing from a same regional pool may best (and in agreement with disturbance theory and the patch-dynamics concept) explain why relatively high similarity (by both Cj and PS) was associated with regional closeness (the two northern data sets, vs. the two southern data sets), rather than to same or similar (as a habi- tat) agricultural crops. Our data are only indica- tive in this respect, but in full agreement with Kinnunen et al. (2001) who found that carabid communities varied significantly among patch- es of farmland but not between fields of differ- ent crops within the patches. This and formerly published research strongly suggest that it is the landscape level of spatial hierarchy at which carabids form communities, and at field or crop level, patterns are less clear and the carabids appear as random assemblages (Thiele 1977, Burel 1989, Burel and Baudry 1995, Östman et al. 2001, see also Kromp 1999, Kinnunen 1999). Carabids are a species rich family in farm- land. Their activity-densities are high through- out growing season. As generalists they are not dependent on any pest species as prey: they are always present in the fields, and may contribute to natural control of pests as a buffer against in- vaders. Economic significance of the group would become obvious only if carabids were missing from the crop fields (see Helenius 1990 for a result of ca. 20% yield reduction in oats, following only partial removal of carabids). Because of their diversity and potential role as beneficials, we suggest including carabids into monitoring of biodiversity in agroecosystems. In designing such schemes, we suggest landscape level sampling frames, rather than randomly choosing individual fields for sampling. Pitfall sampling has an advantage of being much used, which eases comparisons to earlier studies. Acknowledgements. We would like to thank Virpi Vorne for collating the data and Lauri Jauhiainen for program- ming for the rarefaction. Also, our thanks are due to Arja Vasarainen, Timo Tolonen, Ilpo Mannerkoski, Ilpo Rutanen and many others who helped collect the raw material and in compiling the data. The study was financed by public grants from the Academy of Finland, by Ministry of Agri- culture and Forestry, and by a private grant to Juha Hele- nius from the Finnish Entomological Society. References Ahti, T., Hämet-Ahti, L. & Jalas, J. 1968. Vegetation zones and their sections in northwestern Europe. Annales Botanici Fennici 5: 169–211. Bagon, M., Harper, J.L. & Townsend, C.R. 1996. Ecology. Individuals, populations and communities. 3rd Ed. Blackwell Science, Oxford. 1068 p. Burel, F. 1989. Landscape structure effects on carabid beetles spatial patterns in western France. Land- scape Ecology 2: 215–226. – & Baudry, J. 1995. Species biodiversity in changing agricultural landscapes: a case study in the Pays d’Auge France. Agriculture, Ecosystems and Environ- ment 55: 193–200. Coddington, J.A., Young, L.H. & Coyle, F.A. 1996. Esti- mating spider species richness in a southern Appa- lachian cove hardwood forest. The Journal of Arach- nology 24: 111–128. Duelli, P. Obrist, M.K. & Schmatz, D.R. 1999. Biodiversity evaluation in agricultural landscapes: above ground insects. Agriculture, Ecosystems and Environment 74: 33–64. Greenslade, P.J.M. 1964. Pitfall trapping as a method for studying populations of Carabidae (Coleoptera). Jour- nal of Animal Ecology 33: 301–310. Helenius, J. 1990. Effect of epigeal predators on infesta- tion by the aphid Rhopalosiphum padi and on grain yield of oats in monocrops and mixed intercrops. Entomologia experimentalis et applicata 54: 225–236. – 1991a. Insect numbers and pest damage in intercrops vs. monocrops: concepts and evidence from a sys- tem of faba bean, oats and Rhopalosiphum padi (Homoptera, Aphididae). Journal of Sustainable Ag- riculture 1: 57–80. – 1991b. Integrated control of Rhopalosiphum padi, and the role of epigeal predators in Finland. IOBC / WPRS Bulletin 14: 123–130. – 1995. Rate and local scale spatial pattern of adult emergence of the generalist predator Bembidion gut- tula in an agricultural field. Acta Jutlandica 70, 2: 101– 111. –, Holopainen, J., Muhojoki, M., Pokki, P., Tolonen, T. & Venäläinen, A. 1995. Effect of undersowing and green 275 A G R I C U L T U R A L A N D F O O D S C I E N C E I N F I N L A N D Vol. 10 (2001): 261–276. manuring on abundance of ground beetles (Coleop- tera, Carabidae) in cereals. Acta Zoologica Fennica 1996: 156–159. – & Tolonen, T. 1994. Enhancement of generalis aphid predators in cereals: effect of green manuring on re- cruitment of ground beetles (Col., Carabidae). IOBC / WPRS Bulletin 17: 201–210. Holopainen, J.K. 1992. Catch and sex ratio of Carabidae (Coleoptera) in pitfall traps filled with ethylene glycol or water. Pedobiologia 36: 257–261. –, Bergman, T., Hautala, E.L. & Oksanen, J. 1995. The ground beetle fauna (Coleoptera: Carabidae) in rela- tion to properties and foliar fluoride content in spring cereals. Pedobiologia 39: 193–206. – & Helenius, J. 1992. Gut contents of ground beetles (Col., Carabidae), and activity of these and other epigeal predators during an outbreak of Rhopal- osiphum padi (Hom., Aphididae). Acta Agriculturae Scandinavica 42: 57–61. – & Varis, A.-L. 1986. Effects of mechanical barrier and formalin preservative on pitfall catches of carabid beetles (Coleoptera, Carabidae) in arable fields. Jour- nal of Applied Entomology 102: 440–445. Hughes, R.D. 1959. The natural mortality of Erioischia brassicae (Bouché) (Diptera, Anthomyiidae) during the egg stage of the first generation. Journal of Ani- mal Ecology 28: 343–357. Huusela-Veistola, E. 1996. Effects of pesticide use and cultivation techniques on ground beetles (Col., Cara- bidae) in cereal fields. Annales Zoologici Fennici 33: 197–205. – 2000. Effects of pesticide use and perennial grass strips on arthropod fauna in northern field ecosys- tems. Annales Universitatis Turkuensis Ser. AII Tom. 130. 95 p. Kinnunen, H. 1999. In search of spatial scale – Carabid beetle communities in agricultural landscapes. A PhD dissertation, Department of Ecology and Systemat- ics, University of Helsinki. Helsinki. –, Järveläinen, K., Pakkala, T. & Tiainen, J. 1996. The effects of isolation on the occurrence of farmland carabids in a fragmented landscape. Annales Zoo- logici Fennici 33: 165–171. – & Tiainen, J. 1999. Carabid distribution in a farmland mosaic: the effect of patch type and location. Annal- es Zoologici Fennici 36: 149–158. –, Tiainen, J. & Tukia, H. 2001. Farmland carabid beetle communities at multiple levels of spatial scales. Ec- ography 24: 189–197. Kouki, J. & Haila, Y. 1985. Lajimäärä, näytekoko ja rare- faktio – lajimäärän vertailun ongelma. Luonnon Tut- kija 89: 156–159. Kromp, B. 1999. Carabid beetles in sustainable agricul- ture: a review on pest control efficacy, cultivation im- pacts and enhancement. Agriculture, Ecosystems and Environment 74: 187–228. Lindroth, C.H. 1985. The Carabidae (Coleoptera) of Fen- noscandia and Denmark. Fauna Entomologica Scan- dinavica 15, 1. 225 p. – 1986. The Carabidae (Coleoptera) of Fennoscandia and Denmark. Fauna Entomologica Scandinavica 15, 2. 497 p. Lövei, G.L. & Sunderland, K.D. 1996. Ecology and be- haviour of ground beetles (Coleoptera: Carabidae). Annual Review of Entomology 41: 231–256. Niemelä, J., Haila, Y., Halme, E., Pajunen, T. & Punttila, P. 1990. Diversity variation in carabid beetle assem- blages in the southern Finnish taiga. Pedobiologia 34: 1–10. Obrist, M.K. & Duelli, P. 1996. Trapping efficiency of fun- nel- and cup-traps for epigeal arthropods. Mitteilun- gen den Schweizerischen Entomologischen Ge- schellshaft 69: 361–369. Östman, Ö., Ekbom, B., Bengtsson, J. & Weibull, A.-C. 2001. Landscape complexity and farming practice influence the condition of polyphagous carabid bee- tles. Ecological Applications 11: 480–488. Pachepsky, E., Crawford, J.W., Brown, J.L. & Squire, G. 2001. Towards a general theory of biodiversity. Na- ture 410: 923–926. Potts, G.R. & Vickerman, G.P. 1974. Studies on the cere- al ecosystem. Advances in Ecological Research 8: 107–197. Silfverberg, H. 1992. Enumeratio Coleopterorum Fenno- scandiae, Daniae et Baltiae. Helsinki, Helsingin Hyön- teisvaihtoyhdistys. Simberloff, D. 1978. Use of rarefaction and related meth- ods in ecology. In: Dickson, K.L. et al. (eds.). Biolog- ical Data in Water Pollution Assessment: Quantita- tive and Statistical Aanalyses. ASTM STP 652, Amer- ican Society for Testing and Materials, p. 150–165. Southwood, T.R.E. 1978. Ecological methods. Chapman and Hall. London, New York. 524 p. Sunderland, K.D., De Snoo, G.R., Dinter, A., Hance, T., Helenius, J., Jepson, P., Kromp, B., Lys, J.-A., Samu, F., Sotherton, N.W., Toft, S. & Ulber, B. 1995. Density estimation for invertebrate predators in agr- oecosystems. Acta Jutlandica 70, 2: 133–162. Thiele, H.-U. 1977. Carabid beetles in their environments. Springer Verlag, Berlin. 396 p. Varis, A.-L. 1982. Insekticidernas effect på carabidpreda- torerna av kålflugor. Integrerad bekämpning I grön- saker på friland med särskild hänblick på skadedjur, NJF Seminarium nr. 31. p. 25. – 1989. Cabbage field Carabidae (Coleoptera) and their role as natural enemies of Delia radicum and D. flo- ralis (Diptera, Anthomyiidae). Acta Entomologica Fennica 53: 61–63. –, Holopainen, J.K. & Koponen, M. 1984. Abundance and seasonal occurrence of adult Carabidae (Cole- optera) in cabbage, sugar beet and timothy fields in southern Finland. Zeitschrift für angewandte Ento- mologie 98: 62–73. Vasarainen, A. & Kurppa, S. 1996. Vegetation and cara- bid fauna affected by conventional and biological cultivation. In: Proceedings of the 20th International Congress of Entomology, Firenze, Italy, 25–31 Au- gust 1996. p. 661. Wishart, G., Doane, F.J. & Maybee, G.E. 1956. Notes on beetles as predators of eggs of Hylemya brassicae (Bouché) (Diptera, Anthomyiidae). Canadian Ento- mologist 88: 634–639. Wolda, H. 1981. Similarity indices, sample size and di- versity. Oecologia 50: 296–302. 276 A G R I C U L T U R A L A N D F O O D S C I E N C E I N F I N L A N D Helenius, J. et al. Ground beetle diversity SELOSTUS Maakiitäjäisten lajimonimuotoisuus suomalaisilla peltoviljelmillä Juha Helenius, Jarmo K. Holopainen, Erja Huusela-Veistola, Sirpa Kurppa, Pia Pokki ja Anna-Liisa Varis Helsingin yliopisto ja MTT (Maa- ja elintarviketalouden tutkimuskeskus) Maakiitäjäisten lajimonimuotoisuutta suomalaisilla peltoviljelmillä selvitettiin kuudesta toisistaan riip- pumattomasta tutkimuksesta, joista vanhin oli vuo- delta 1978 ja uusin vuodelta 1994. Kuoppa-ansapyyn- nillä koottu aineisto käsitti 97 799 maakiitäjäisyksi- löä, jotka määritettiin 111 lajiin. Shannonin-Wienerin diversiteetti-indeksin H’ arvo oli tyypillisesti noin 2,5. Kuudensadan yksilön otoskokoon rarefoitu, odo- tettavissa oleva lajimäärä yksittäiseltä peltolohkolta oli noin 30 lajia. Viisi runsainta lajia muodostivat 42 % ja 30 runsainta lajia 98 % koko yksilömääräs- tä. Lajimäärän ja runsaussuhteet huomioon ottava Renkosen prosentuaalisen samankaltaisuuden indek- si PS sai arvoja 16 % samankaltaisuudesta aina 48 % samankaltaisuuteen osa-aineistojen välillä. Samalta maantieteelliseltä alueelta pyydetyt aineistot olivat kasvustotyypistä riippumatta samankaltaisempia kuin eri alueilta pyydetyt aineistot. Suomessa pellot ovat tyypillisesti ainakin osittain metsien ympäröimiä. Verrattuna metsälajistosta jul- kaistuihin tietoihin, peltomaiden maakiitäjäisyhteisöt ovat lajirikkaampia, ja niissä lajien väliset runsaus- suhteet ovat tasaisempia kuin metsien maakiitäjäis- yhteisöissä. Tarkastelemme tätä yhteisöekologisen häiriöteorian valossa, jonka mukaan yhteisöjen laji- diversiteetit ovat korkeimmillaan kohtuullisesti (kes- kinkertaisen usein) häirityissä elinympäristöissä. Tuloksemme korostavat viljelyalueen (alue-eko- logisen tason) merkitystä lohkotason tai viljelykas- vilajin sijasta, pyrittäessä ymmärtämään viljelymai- den maakiitäjäisdiversiteetin vaihtelua paikasta toi- seen. Ehdotamme, että maakiitäjäislajistot otetaan mukaan maatalousympäristön biodiversiteetin seuran- taan, ja että seuranta näiden osalta järjestettäisiin vil- jelyalueiden mittakaavassa. 277 A G R I C U L T U R A L A N D F O O D S C I E N C E I N F I N L A N D Vol. 10 (2001): 261–276. Species of Carabidae and their total catch using pitfall-traps. Thermal window of Day Degrees (DD. above 5°C) of trapping, as well as DD range in which the species was trapped. The DD range gives an indication of thermal activity range, but is artificially limited by the period of pitfall trapping (see also Table 1). (Note: ‘0’ denotes not caught, ‘–’ denotes not identi- fied). Species Sii Out Jok SW Fin Viik I Viik II DD range: 74.3- 20.2- 18.8 81.9 40.7 8.1 min max 876.9 580.6 -1106.9 510.9 1533.8 1362.4 Acupalpus meridianus (Linnaeus) 0 0 0 6 14 332 66.5 849.3 A. parvulus (Sturm) 0 0 0 0 5 28 87.4 529.9 Agonum fuliginosum (Panzer) 41 0 0 0 0 3 74.3 876.9 A. gracile Sturm 0 0 0 13 0 0 231.5 483.3 A. micans Nicolai 1 0 0 0 0 0 74.3 876.9 A. muelleri (Herbst) 245 53 0 0 0 0 32.7 876.9 A. piceum (Linnaeus) 0 9 0 0 0 0 69 400.7 A. sexpunctatum (Linnaeus) 47 16 0 0 0 0 74.3 876.9 Amara aenea (Degeer) 5 7 – – 0 9 74.3 1007.3 A. apricaria (Paykull) 3 14 – – 480 106 56.6 1320.9 A. aulica (Panzer) 3 4 – 5 73 154 74.3 1160.3 A. bifrons (Gyllenhal) 14 8 – – 236 2554 8.1 1257.1 A. brunnea (Gyllenhal) 0 0 – – 0 1 970.8 1028.4 A. communis (Panzer) 3 21 – – 3 233 8.1 1127 A. consularis (Duftschmid) 0 0 – – 29 50 168.3 1238 A. convexiuscula (Marsham) 0 0 – – 0 16 413.5 1040.2 A. curta Dejean 0 1 – – 3 0 85.6 807.7 A. cursitans Zimmermann 0 0 – – 0 1 1136.6 1169.7 A. equestris (Duftschmid) 0 0 – – 7 2 168.3 965.1 A. eurynota (Panzer) 1 0 – 23 115 33 61.6 1320.9 A. famelica Zimmermann 2 2 – – 20 0 74.3 883.1 A. familiaris (Duftschmid) 0 17 – – 7 3 88 715.4 A. fulva (Müller) 0 0 – – 8 110 134 1195.5 A. gebleri Dejean 0 1 – – 0 0 231.2 313.5 A. ingenua (Duftschmid) 0 0 – – 2 172 193.9 1227.4 A. littorea Thomson 0 0 – – 0 1 1136.6 1169.7 A. lunicollis Schiödte 0 8 – – 1 2 102.2 764 A. majuscula (Chaudoir) 0 0 – – 7 39 115.8 1205.4 A. montivaga Sturm 0 0 – – 1 2 58.3 444 A. municipalis (Duftschmid) 0 0 – – 1 176 328.7 1257.1 A. nitida Sturm 1 0 – – 0 0 74.3 876.9 A. ovata (Fabricius) 2 0 – – 1 2 74.3 876.9 A. plebeja (Gyllenhal) 23 101 – 9 207 0 35.9 1257.1 A. quenseli (Schönherr) 1 0 – – 0 0 74.3 876.9 A. similata (Gyllenhal) 2 6 – – 0 5 35.9 952 Amara sp. 0 0 745 293 371 5 18.8 1533.8 Anchomenus dorsalis (Pontoppidan) 0 0 0 1 53 132 58.3 1197.8 Anisodactylus binotatus (Fabricius) 0 1 0 0 0 0 313.5 400.7 Asaphidion flavipes (Linnaeus) 1 110 0 18 6 3 20.2 876.9 A. pallipes (Duftschmid) 0 12 0 0 1 162 135.1 1040.2 Badister bullatus (Schrank) 0 0 0 0 0 1 328.7 358.5 B. lacertosus Sturm 0 0 0 0 1 0 152.6 206.9 Bembidion biguttatum (Fabricius) 0 0 0 2 0 0 287.1 472.8 B. bruxellense Wesmaël 390 928 0 202 6 111 20.2 970.8 B. femoratum Sturm 6 0 0 0 0 75 74.3 1147.9 continued on the next page A G R I C U L T U R A L A N D F O O D S C I E N C E I N F I N L A N D Appendix 1 278 A G R I C U L T U R A L A N D F O O D S C I E N C E I N F I N L A N D Helenius, J. et al. Ground beetle diversity continued from the preceding page Species Sii Out Jok SW Fin Viik I Viik II DD range: 74.3- 20.2- 18.8 81.9 40.7 8.1 min max 876.9 580.6 -1106.9 510.9 1533.8 1362.4 B. gilvipes Sturm 0 12 976 79 0 5 18.8 1106.9 B. guttula (Fabricius) 112 668 1938 1019 2957 11 18.8 1320.9 B. lampros (Herbst) 53 227 121 393 363 874 8.1 1533.8 B. nigricorne Gyllenhal 0 0 0 0 3 0 180.6 395.8 B. properans (Stephens) 2 131 38 57 1217 2614 16.6 1533.8 B. quadrimaculatum (Linnaeus) 61 876 341 964 1011 1561 8.1 1533.8 B. tetracolum Say 0 0 0 0 0 2 18.8 934.3 Bembidion sp. 0 0 6 0 54 0 728.6 1227.4 Bradycellus caucasicus Chaudoir 0 1 0 0 0 4 45.7 1195.5 B. harpalinus (Audinet-Serville) 0 0 0 0 0 3 1169.7 1227.4 Broscus cephalotes (Linnaeus) 0 0 0 0 2 38 187.4 1147.9 Calathus ambiguus (Paykull) 0 0 0 0 1 309 271.8 1197.8 C. erratus (Sahlberg) 0 2 1 16 97 579 26 1227.4 C. melanocephalus (Linnaeus) 4 7 0 33 808 2017 26 1533.8 C. micropterus (Duftschmid) 0 0 0 0 4 0 443.7 715.4 Carabus cancellatus Illiger 355 270 0 0 0 0 20.2 876.9 C. granulatus Linnaeus 10 5 121 0 2 5 18.8 1106.9 C. hortensis Linnaeus 0 0 0 0 1 1 830.5 1007.3 C. nemoralis Müller 0 0 2 19 8 47 52.3 1362.4 C. violaceus Linnaeus 0 0 0 0 1 0 810.9 934.3 Carabus sp. 0 0 2 44 0 0 51 663.6 Clivina fossor (Linnaeus) 366 1073 202 2073 5819 3041 8.1 1533.8 Cychrus caraboides (Linnaeus) 0 0 0 0 1 2 248.9 1177.3 Dicheirotrichus rufithorax (Sahlberg) 0 0 0 0 0 7 231.4 911.5 Dromius sigma (Rossi) 0 0 3 4 0 5 26 483.5 Dyschirius globosus (Herbst) 0 316 2 32 13 13 20.2 799.8 D. politus (Dejean) 0 0 0 0 0 3 134 483.5 D. thoracicus (Rossi) 0 7 0 0 0 0 83.9 400.7 Dyschirius sp. 0 0 41 0 0 0 18.8 1106.9 Elaphrus riparius (Linnaeus) 1 12 0 0 0 1 74.3 876.9 Elaphrus sp. 0 0 0 5 0 0 95.2 455.1 Harpalus affinis (Schrank) 8 36 102 219 253 522 29.4 1320.9 H. latus (Linnaeus) 0 5 68 57 4 10 18.8 1047.3 H. luteicornis (Duftschmid) 0 0 0 0 1 0 87.4 127.2 H. quadripunctatus Dejean 1 0 0 0 3 15 74.3 1195.5 H. rufipes (Degeer) 19 28 133 243 2245 1866 52.3 1533.8 H. tardus (Panzer) 0 0 0 0 0 6 66.7 586.5 Harpalus sp. + Ophonus sp. 0 0 2 28 2 0 187.4 716.3 Lebia chlorocephala (Hoffmannsegg) 0 1 0 1 0 0 273.2 523.8 Leistus ferrugineus (Linnaeus) 0 0 0 0 0 6 735.7 1227.4 L. terminatus (Hellwig) 0 1 5 0 16 27 145 1320.9 Leistus sp. 0 0 0 0 1 0 715.4 792.4 Loricera pilicornis (Fabricius) 71 125 136 74 210 224 16.6 1320.9 Microlestes minutulus (Goeze) 0 0 0 9 53 17 133.5 846.5 Notiophilus aquaticus (Linnaeus) 0 0 0 0 0 74 16.6 1301.2 N. palustris (Duftschmid) 0 0 0 4 0 1 231.5 1227.4 Notiophilus sp. 0 0 1 0 0 0 1 663.6 822.6 Olisthopus rotundatus (Paykull) 0 0 0 15 0 0 95.2 232 continued on the next page A G R I C U L T U R A L A N D F O O D S C I E N C E I N F I N L A N D Appendix 1 279 A G R I C U L T U R A L A N D F O O D S C I E N C E I N F I N L A N D Vol. 10 (2001): 261–276. continued from the preceding page Species Sii Out Jok SW Fin Viik I Viik II DD range: 74.3- 20.2- 18.8 81.9 40.7 8.1 min max 876.9 580.6 -1106.9 510.9 1533.8 1362.4 Oodes helopioides (Fabricius) 0 1 0 0 0 0 250.6 335.2 Ophonus nitidulus Stephens 0 0 0 0 0 1 444.2 496.7 O. puncticollis (Paykull) 0 0 0 0 5 5 196.5 846.5 O. rufibarbis (Fabricius) 0 0 0 1 0 84 134 1169.7 Patrobus assimilis Chaudoir 0 0 0 0 1 0 135.3 180.6 P. atrorufus (Ström) 2230 376 124 1156 457 532 20.2 1502.7 Platynus livens (Gyllenhal) 0 0 0 0 1 0 538.7 566 P. obscurus (Herbst) 0 0 0 13 0 0 226.7 483.3 Pterostichus crenatus (Duftschmid) 96 27 0 19 12 3 52.3 1070.1 P. cupreus (Linnaeus) 758 739 2064 693 19 3 18.8 1533.8 P. melanarius (Illiger) 1650 761 1409 2042 6630 811 18.8 1533.8 P. minor (Gyllenhal) 0 0 96 0 0 0 18.8 1076.2 P. niger (Schaller) 1556 21 668 386 448 134 58.3 1320.9 P. nigrita (Paykull) 0 5 0 0 0 0 76.3 197.9 P. oblongopunctatus (Fabricius) 31 0 0 10 0 2 29.4 876.9 P. strenuus (Panzer) 44 59 219 90 3 31 16.6 1227.4 Pterostichus sp. 0 0 17 0 0 0 66.7 997.6 Stomis pumicatus (Panzer) 0 0 0 0 0 3 328.7 448.6 Syntomus foveatus (Geoffroy) 0 0 0 0 0 1 248.9 288.1 S. truncatellus (Linnaeus) 0 0 0 0 0 150 8.1 1147.9 Synuchus vivalis (Illiger) 123 5 4 81 989 183 74.3 1502.7 Trechus discus (Fabricius) 272 23 87 217 6292 171 74.3 1533.8 T. micros (Herbst) 0 0 27 75 809 199 40.7 1320.9 T. quadristriatus (Schranck) 36 3 592 124 1041 1004 18.8 1533.8 T. rubens (Fabricius) 1 0 0 0 7 0 74.3 1030 T. secalis (Paykull) 69 18 365 993 2814 2967 18.8 1533.8 Trechus sp. 0 0 2 0 3 1 305.3 1106.9 Trichocellus placidus (Gyllenhal) 2 0 0 0 0 1 16.6 876.9 A G R I C U L T U R A L A N D F O O D S C I E N C E I N F I N L A N D Appendix 1 Title Introduction Material and methods Results Discussion References SELOSTUS