Saproxylic insect assemblages are essential functional components of forest ecosystems that can be affected by forest management.We used a split-plot ANOVA design to analyze differences in selected saproxylic insects...Saproxylic insect assemblages are essential functional components of forest ecosystems that can be affected by forest management.We used a split-plot ANOVA design to analyze differences in selected saproxylic insects（all arthropod orders and dipteran and parasitic hymenopteran families） emerging from dead wood of sites with different logging histories（horse-logged,mechanically-logged and unlogged）,tree species（Populus and Picea）,stage of decay（early-and late-decay stages） and posture（standing and downed logs） in the boreal forest of central Canada.No clear effects of logging history were seen for the studied taxa; however,interaction between logging history and other dead wood features was apparent.Cecidomyiidae consistently emerged more from Populus than from Picea dead wood.Most of the studied saproxylic families were more abundant in late-decay than in early-decay wood.Dipterans of the Cecidomyiidae,Ceratopogonidae,Empididae,Mycetophilidae and Sciaridae families,and hymenopterans of the Diapriidae and Ichneumonidae families were significantly more abundant in downed than in standing dead wood.In contrast,Mymaridae was most abundant in standing dead wood.Our study provides evidence that some insects at high taxonomic levels respond differently to dead wood quality,and this could inform future management strategies in the boreal forest for the conservation of saproxylic fauna and their ecological functions.展开更多
Soil invertebrates contribute to critical ecosystem processes in tropical regions,being highly diverse yet poorly studied.The addition of pyrolyzed biomass(biochar)to tropical soils can increase forest productivity by...Soil invertebrates contribute to critical ecosystem processes in tropical regions,being highly diverse yet poorly studied.The addition of pyrolyzed biomass(biochar)to tropical soils can increase forest productivity by enhancing the availability of P and micronutrients,but effects on the invertebrate community have received little attention.Here,we present a 3-year study of litter invertebrates captured in pitfall traps in secondary forests experimentally enriched with non-timber forest product(NTFP)species and amended with kiln and traditional mound biochars at 10 t ha^(−1)in the Ecuadorian Amazon in a poorer alluvial sandy soil,and a colluvial soil with higher nutrient content.Soil conditions and seasonality were the main determinants of soil invertebrate community structure in multivariate analyses;however,biochar treatment effects were also detectable.Predators(ants and spiders)and microbivores(especially Poduromorpha)were the dominant functional groups in the study,with predators increasing over the collection seasons and microbivores decreasing.Microbivores showed reduced abundance at high Al availability,which was reduced by biochar addition.In contrast,predators showed increased abundance with increasing soil Al,but this pattern was only pronounced in the poorer alluvial soil and mixed NTFP treatment.In the colluvial soil,with higher nutrient content,parasitoid wasps increased in abundance with biochar additions relative to controls,while isopods showed a positive response to kiln-made biochar in the mixed NTFP treatment only.The findings indicate responses of soil invertebrates,in particular Poduromorpha,ants,and parasitoid wasps,to biochar amendments,but with patterns that vary over time and that are dependent on the specific biochar used as well as the soil type.展开更多
基金supported by the Ontario Ministry of Natural Resources and Forestry(OMNRF)funded through the Sustainable Forest Management Network and the Faculty of Forestry,University of Toronto
文摘Saproxylic insect assemblages are essential functional components of forest ecosystems that can be affected by forest management.We used a split-plot ANOVA design to analyze differences in selected saproxylic insects（all arthropod orders and dipteran and parasitic hymenopteran families） emerging from dead wood of sites with different logging histories（horse-logged,mechanically-logged and unlogged）,tree species（Populus and Picea）,stage of decay（early-and late-decay stages） and posture（standing and downed logs） in the boreal forest of central Canada.No clear effects of logging history were seen for the studied taxa; however,interaction between logging history and other dead wood features was apparent.Cecidomyiidae consistently emerged more from Populus than from Picea dead wood.Most of the studied saproxylic families were more abundant in late-decay than in early-decay wood.Dipterans of the Cecidomyiidae,Ceratopogonidae,Empididae,Mycetophilidae and Sciaridae families,and hymenopterans of the Diapriidae and Ichneumonidae families were significantly more abundant in downed than in standing dead wood.In contrast,Mymaridae was most abundant in standing dead wood.Our study provides evidence that some insects at high taxonomic levels respond differently to dead wood quality,and this could inform future management strategies in the boreal forest for the conservation of saproxylic fauna and their ecological functions.
基金Funding for this research was provided to P.R.G.by the Connaught Fund Doctoral Awards from the University of Toronto.Universidad Estatal Amazonica provided additional financing by the internal grant ID-GCA-002-2014.Additional funding was provided by grants from the Canadian Natural Sciences and Engineering Research Council to S.T.,and S.S.
文摘Soil invertebrates contribute to critical ecosystem processes in tropical regions,being highly diverse yet poorly studied.The addition of pyrolyzed biomass(biochar)to tropical soils can increase forest productivity by enhancing the availability of P and micronutrients,but effects on the invertebrate community have received little attention.Here,we present a 3-year study of litter invertebrates captured in pitfall traps in secondary forests experimentally enriched with non-timber forest product(NTFP)species and amended with kiln and traditional mound biochars at 10 t ha^(−1)in the Ecuadorian Amazon in a poorer alluvial sandy soil,and a colluvial soil with higher nutrient content.Soil conditions and seasonality were the main determinants of soil invertebrate community structure in multivariate analyses;however,biochar treatment effects were also detectable.Predators(ants and spiders)and microbivores(especially Poduromorpha)were the dominant functional groups in the study,with predators increasing over the collection seasons and microbivores decreasing.Microbivores showed reduced abundance at high Al availability,which was reduced by biochar addition.In contrast,predators showed increased abundance with increasing soil Al,but this pattern was only pronounced in the poorer alluvial soil and mixed NTFP treatment.In the colluvial soil,with higher nutrient content,parasitoid wasps increased in abundance with biochar additions relative to controls,while isopods showed a positive response to kiln-made biochar in the mixed NTFP treatment only.The findings indicate responses of soil invertebrates,in particular Poduromorpha,ants,and parasitoid wasps,to biochar amendments,but with patterns that vary over time and that are dependent on the specific biochar used as well as the soil type.
