Ground‐dwelling spiders (Arachnida, Araneae) in fragmented old forests and surrounding managed forests in southern Finland

Pajunen, Timo; Haila, Yrjö; Halme, Eero; Niemelä, Jari; Punttila, Pekka

doi:10.1111/j.1600-0587.1995.tb00119.x

Cited by 70 publications

(163 citation statements)

References 19 publications

Supporting

Mentioning

152

Contrasting

Unclassified

Order By: Relevance

“…These stands exhibited high spider species richness and open habitat species richness as well as low dominance (as found by Pajunen et al, 1995) as well as the greatest cover of lower field layer vegetation. The vegetation of the pre-thicket plots was dominated by species typical of open habitats and was generally taller, and probably more structurally diverse, than in the more mature plots.…”

Section: Pre-thicket Standsmentioning

confidence: 99%

Structural indicators of spider communities across the forest plantation cycle

Oxbrough

Gittings

O’Halloran

et al. 2005

Forest Ecology and Management

113

View full text Add to dashboard Cite

Given the expansion of plantation forests in Ireland over recent years, there is a need to assess their impact on biodiversity and to identify how sustainable forest management strategies can incorporate biodiversity. We aimed to assess the impact of plantation forests on spider communities and identify structural indicators of their diversity. Pitfall traps were used to sample spiders in Sitka spruce (Picea sitchensis) and ash (Fraxinus excelsior) plantations at different stages of the forest cycle and cover of vegetation, dead wood and soil organic content were measured within each site. Ordinations revealed that spider assemblages were separated by both forest development and canopy species across the forest cycle. The pre-thicket ash and spruce assemblages were similar, whereas canopy species had a greater effect in the more structurally developed stands. The mature ash plots formed a distinct group from the other stands. Overall species richness was highest in the spruce and ash pre-thicket stands, and in the mature spruce stands with a more open canopy.Mature ash stands had the lowest species richness. Lower field layer vegetation was positively correlated with total spider species richness and open habitat specialist species richness whereas canopy closure had a negative effect on these species variables. Forest spider species were positively correlated with litter cover, depth and twig cover. To enhance the diversity of open and forest spider species within a stand, the growth of lower field layer vegetation should be encouraged at all stages of the forest cycle, whilst retaining features typical of a mature forest. Within a plantation, a mosaic of different aged stands will sustain both open and forest specialists to enhance diversity. The distinct assemblages found in the mature plantations indicate that on a landscape scale, the establishment of both ash and spruce plantations will enhance overall diversity.

show abstract

Section: Pre-thicket Standsmentioning

confidence: 99%

Structural indicators of spider communities across the forest plantation cycle

Oxbrough

Gittings

O’Halloran

et al. 2005

Forest Ecology and Management

113

View full text Add to dashboard Cite

show abstract

“…2F-J ; Davies & Margules, 1998 ;Kotze & Samways, 1999Bolger et al, 2000). In a study of spider communities in forest fragments in Finland, it was shown that large hunting spiders were most abundant near forest edges where the environment was warmer, more open, and the leaf litter layer was thick enough to allow stratification of adults and juveniles, which reduced the probability of cannibalism (Pajunen et al, 1995). By contrast, in the same forest fragments, small web-building spiders were more likely to inhabit the forest interior, where the herb and moss cover provided suitable microhabitat structures for web construction (Pajunen et al, 1995).…”

Section: Edge Effects (1 ) Community Composition At Habitat Bounmentioning

confidence: 99%

Confounding factors in the detection of species responses to habitat fragmentation

2005

View full text Add to dashboard Cite

Habitat loss has pervasive and disruptive impacts on biodiversity in habitat remnants. The magnitude of the ecological impacts of habitat loss can be exacerbated by the spatial arrangement -or fragmentation -of remaining habitat. Fragmentation per se is a landscape-level phenomenon in which species that survive in habitat remnants are confronted with a modified environment of reduced area, increased isolation and novel ecological boundaries. The implications of this for individual organisms are many and varied, because species with differing life history strategies are differentially affected by habitat fragmentation. Here, we review the extensive literature on species responses to habitat fragmentation, and detail the numerous ways in which confounding factors have either masked the detection, or prevented the manifestation, of predicted fragmentation effects.Large numbers of empirical studies continue to document changes in species richness with decreasing habitat area, with positive, negative and no relationships regularly reported. The debate surrounding such widely contrasting results is beginning to be resolved by findings that the expected positive species-area relationship can be masked by matrix-derived spatial subsidies of resources to fragment-dwelling species and by the invasion of matrix-dwelling species into habitat edges. Significant advances have been made recently in our understanding of how species interactions are altered at habitat edges as a result of these changes. Interestingly, changes in biotic and abiotic parameters at edges also make ecological processes more variable than in habitat interiors. Individuals are more likely to encounter habitat edges in fragments with convoluted shapes, leading to increased turnover and variability in population size than in fragments that are compact in shape. Habitat isolation in both space and time disrupts species distribution patterns, with consequent effects on metapopulation dynamics and the genetic structure of fragment-dwelling populations. Again, the matrix habitat is a strong determinant of fragmentation effects within remnants because of its role in regulating dispersal and dispersalrelated mortality, the provision of spatial subsidies and the potential mediation of edge-related microclimatic gradients.We show that confounding factors can mask many fragmentation effects. For instance, there are multiple ways in which species traits like trophic level, dispersal ability and degree of habitat specialisation influence specieslevel responses. The temporal scale of investigation may have a strong influence on the results of a study, with short-term crowding effects eventually giving way to long-term extinction debts. Moreover, many fragmentation effects like changes in genetic, morphological or behavioural traits of species require time to appear. By contrast, synergistic interactions of fragmentation with climate change, human-altered disturbance regimes, species interactions and other drivers of population decline may magnify the impacts...

show abstract

“…Ha tájléptékű diverzitást vizsgálunk, akkor a fajszám-élőhelyméret összefüggés az egyik legfontosabb ökológiai elmélet (Lawton 1999). Miyashita et al (1998) a habitat mérete és a pókközösségek fajszáma közt pozitív korrelációt, Hopkins és Webb (1984), Webb és Hopkins (1984) negatív kapcsolatot mutatott ki, mert a környező foltok populációi növekvő arányban bejutnak az élőhelyre (Usher et al 1993), Pajunen et al (1995), Bonte et al (2002), Gibb és Hochuli (2002) nem talált összefüggést. Pearce et al (2005) vizsgálata szerint a kis foltokban alacsonyabb a fajszám és az egyedszám, mert a növekvő mérettel növekedik a mikrohabitatok száma/változatossága a folton belül.…”

Section: Tájléptékű Váltózók Hatása a Pókközösségekreunclassified

“…Hopkins és , Webb és Hopkins (1984) negatív kapcsolatot talált a habitat mérete és a fajszám közt, számos szerző vizsgálata alapján nincs köztük összefüggés (Pajunen et al 1995, Bolger et al 2000, Bonte et al 2002, Gibb és Hochuli 2002, Pearce et al 2005, Miyashita et al (1998) Az egyes élőhelyfoltok közti "mátrix‖ kevésbé veszélyes az elsősorban az élőhely-szigetekre jellemző fajok számára, mint a valódi szigetek esetén, itt hosszabb ideig túlélhetnek, és valószínűleg nagyobb távolságokat tehetnek meg . A fülöpházi vizsgálat során is gyűjtöttünk erdei fajokat a nyílt homoki gyepen (pl.…”

Ground‐dwelling spiders (Arachnida, Araneae) in fragmented old forests and surrounding managed forests in southern Finland

Cited by 70 publications

References 19 publications

Structural indicators of spider communities across the forest plantation cycle

Structural indicators of spider communities across the forest plantation cycle

Confounding factors in the detection of species responses to habitat fragmentation

Dél-alföldi pókközösségek szerkezete

Contact Info

Product

Resources

About