지형과 고도가 논둑에 서식하는 토양성거미의 군집과 다양성에 미치는 영향을 조사하였다. 지형의 영향평가를 위해 벼재배기에 산간지와 평야지에서 비교한 결과 거미의 군집구조가 달랐으며 발생밀도는 산간지보다 평야지에서 높았다. 늑대거미과가 가장 우점하였으며 이사고늑대거미 (P. isago)의 발생밀도는 산간지보다 평야지에서 높았다. 거미군집의 발생은 국지 (100 km2) 및 지역 (1,000 km2) 범위에서 유사하였다. 고도의 영향과 관련하여 휴한기에 지형이 유사한 장수와 정읍 지역을 비교한 결과 발생밀도는 지역 간 차이가 없었으나, 긴마디늑대거미속 (Pardosa spp.) 3종의 발생밀도는 정읍에서 높았다. 이러한 결과는 지형과 고도가 군집 수준에서 토양성 논거미의 다양성지수에 미치는 영향은 크지 않으나, 종 수준에서 논에 의존적인 늑대 거미과의 우점종에 영향을 줄 수 있다는 것을 보여준다
Epigeic spiders (Araneae) were surveyed in apple orchards under different farming practices (organic and conventional) in Muju-gun, Jeollabuk-do, Korea. The study was conducted from April to October in 2013 with 2 weeks interval using pitfall traps. Collected spiders were identified as 20 species of 6 families from 819 individuals in organic orchardⅠ, 19 species of 10 families from 759 individuals in orchardⅡ and 16 species of 8 families from 209 individuals in conventional orchard for from 1,787 captured spiders. Biodiversity was analyzed with species richness, abundance and Shannon diversity index (H΄). Species richness was statistically higher in organic orchard than in conventional orchard. Organic orchardⅡ comprised the greatest abundance followed by organic orchard and conventional. But species diversity was the highest in organic orchardⅡ, intermediate in conventional orchard and the lowest in orchardⅠ. Lycosidae was the most dominant family in all orchards regardless farming practices. However, Linyphiidae dominated in organic orchards only. The most dominant species were Erigone koshiensis (Linyphiidae) in organicⅠ, Pardosa laura (Lycosidae) in organicⅡ and Arctosa pungcheunensis (Lycosidae) in conventional orchard.
This study was conducted to compare the community structure and biodiversity of epigeic spiders between pear fields cultivated by integrated pest management (IPM) and organic methods. This is the first study of this kind to be conducted in Korea. Eighty-four spider species from 22 families were identified among the collected 2,489 arthropods, with 754 individuals being sampled from IPM fields and 1,735 individuals from organic fields. Generally, Theridiidae, Linyphiidae, Lycosidae, Agelenidae, Gnaphosidae, and Salticidae were the dominant spider families in the pear orchard regardless of the farming methods, and species richness and abundance were higher in organic fields than in IPM fields. The dominant species were the wolf spiders (Lycosidae) and stone spiders (Gnaphosidae), and their cumulative abundance was 70.7% in IPM fields and 72.7% in organic fields. The community structure between organic and IPM fields was heterogeneous, with a 45% similarity level. Biodiversity, species richness, abundance, and species diversity index were higher in organic fields than in IPM fields, and significantly different between the farming methods. Seasonal fluctuations in biodiversity were similar in both IPM and organic fields. The species richness and species diversity index increased and the abundance decreased in the second half of the cultivation period. This study on the community structure and biodiversity of epigeic spiders, which form one of the most important predator groups, will provide principal ecological and faunistic information required to maintain the biodiversity of useful arthropods in agricultural ecosystems and help implement sustainable agriculture based on the active use of natural enemies.