Forest defoliator outbreaks alter nutrient cycling in northern waters

Woodman, Samuel G.; Khoury, Sacha; Fournier, Ronald E.; Emilson, Erik J. S.; Gunn, John M.; Rusak, James A.; Tanentzap, Andrew J.

doi:10.1038/s41467-021-26666-1

Cited by 15 publications

(8 citation statements)

References 87 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Hence, insect-induced changes to the litter decomposition pathway could result in alterations to the plantlitter-soil feedback (PLSF) pathway (Veen et al 2019b). Despite recent advances in the understanding of the role of litter decomposition in soil nutrient cycling processes (Woodman et al 2021), and how this may affect plant fitness, few studies have considered how insect herbivory might modify the PLSF pathway (e.g., (Burghardt et al 2018).…”

Section: Introductionmentioning

confidence: 99%

Plant-litter-soil feedbacks in common grass species are slightly negative and only marginally modified by litter exposed to insect herbivory

et al. 2022

View full text Add to dashboard Cite

Purpose Insect herbivory affects plant growth, nutrient and secondary metabolite concentrations and litter quality. Changes to litter quality due to insect herbivory can alter decomposition, with knock on effects for plant growth mediated through the plant-litter-soil feedback pathway. Methods Using a multi-phase glasshouse experiment, we tested how changes in shoot and root litter quality of fast- and slow-growing grass caused by insect herbivores affect the performance of response plants in the soil in which the litter decomposed. Results We found that insect herbivory resulted in marginal changes to litter quality and did not affect growth when plants were grown with fast- versus slow-growing litter. Overall, presence of litter resulted in reduced root and shoot growth and this effect was significantly more negative in shoots versus roots. However, this effect was minimal, with a loss of c. 1.4% and 3.1% dry weight biomass in roots versus shoots, respectively. Further, shoot litter exposed to insect herbivory interacted with response plant identity to affect root growth. Conclusions Our results suggest that whether litter originates from plant tissues exposed to insect herbivory or not and its interaction with fast- versus slow-growing grasses is of little importance, but species-specific responses to herbivory-conditioned litter can occur. Taken collectively, the overall role of the plant-litter-soil feedback pathway, as well as its interaction with insect herbivory, is unlikely to affect broader ecosystem processes in this system.

show abstract

Section: Introductionmentioning

confidence: 99%

Plant-litter-soil feedbacks in common grass species are slightly negative and only marginally modified by litter exposed to insect herbivory

et al. 2022

View full text Add to dashboard Cite

show abstract

“…As a result, this N-rich frass leaches into catchment basins, increasing the N concentration in lakes by an average of 0.03 mg L -1 (Woodman et al 2021), which in turn stimulates conditions for increased microbial activity. Growing microbial populations discharges CO2 as an element of egestion, resulting in a recurring pattern of increasing microbial activity and CO2 accumulation near the surface of lakes (Woodman et al 2021). The presence of CO2 in large quantities near lake surfaces suppresses the growth of CO2 assimilating algae (Raven et al, 2012), further exacerbating CO2 concentrations.…”

Section: )mentioning

confidence: 99%

Climate change and human footprint increase insect defoliation across central boreal forests of Canada

Kalamandeen

Gulamhussein²,

Castro³

et al. 2022

Preprint

View full text Add to dashboard Cite

Anthropogenic climate change is contributing to increased insect infestation globally, leading to pest population growth, expansion of niche and geographic range as well as increased outbreak frequencies, resulting in economic losses and reduction in food security. In recent years, spongy moth (Lymantria dispar dispar), jack pine budworm (Choristoneura pinus pinus), large aspen tortrix (Choristoneura conflictana) and spruce budworm (Choristoneura fumiferana) caused widespread defoliation across one of Canada’s most forested provinces, Ontario. Such outbreaks have been limited to field sightings around Ontario, with relatively few studies exploring potential anthropic and climate drivers of infestation. Using random forest probability estimates and satellite data downscaled to 1km spatial resolution from the Moderate Resolution Imaging Spectroradiometer (MODIS), we reveal considerable expansion of insect defoliation across Ontario between 2018 and 2020 than previously recorded. High probability of infestation grew by 1300% from 2018 to 2020, an area expansion of ~40,000 km2 in the northwest and southern parts of the province. Much of the geographic expansion of outbreaks was driven by increasing temperature, and for the first time, linked to the proximity to roads. This expansion presents an important and alarming new challenge for forest conservation and management in Ontario, in particular, and Canada in general.

show abstract

“…The consequences of insect outbreaks contain multiple and interacting influences in ecosystems (Yang 2012; Woodman et al . 2021) and threaten forest biodiversity and ecosystem services (Freer‐Smith & Webber 2017).…”

Section: Introductionmentioning

confidence: 99%

Hundreds of billions of silent outbreaks: A historic outbreak record of the gall midge Schizomyia castanopsisae (Diptera: Cecidomyiidae) on the Izu Islands, Tokyo, Japan, and its potential mechanism

Tokuda

Kawauchi

Matsuda

et al. 2022

Entomological Science

View full text Add to dashboard Cite

Herbivore outbreaks cause serious damage to forest trees. In recent decades, outbreaks of the gall midge Schizomyia castanopsisae (Diptera: Cecidomyiidae) inducing inflorescence galls on Castanopsis sieboldii (Fagaceae) occurred in the Izu Islands, Tokyo, Japan. We investigated the gall density on the islands and estimated the larval population on Miyakejima Island. We also surveyed seasonal changes in larval age structure, presence of natural enemies, larval cold tolerance, and thermal effects on the adult emergence. In addition, we conducted molecular phylogenetic analyses of S. castanopsisae populations among different localities. The gall density was particularly high in southern parts (from Miyakejima to Aogashima) of the Izu Islands. The gall midge seemed to have been expanding its range toward northern parts in recent years. On Miyakejima, the larval population was estimated to be approximately 158 and 36 bn in 2017 and 2018, respectively. Parasitoids were not found in the dissection of galls. A cold temperature treatment did not affect the percentage of adult emergence. Developmental zero and thermal constant during the period from larval departure to adult emergence were estimated to be 4.7 C and 588.2 C-days in males and 7.4 C and 476.2 C-days in females, and the adults were predicted to emerge in April. Populations in Kyushu were genetically distinct from those in Okinawajima and the Izu Islands, but a common haplotype was found between the latter two localities. These imply that S. castanopsisae on the Izu Islands may be a recent invasion, and the absence of natural enemies causes its outbreaks.

show abstract

Forest defoliator outbreaks alter nutrient cycling in northern waters

Cited by 15 publications

References 87 publications

Plant-litter-soil feedbacks in common grass species are slightly negative and only marginally modified by litter exposed to insect herbivory

Plant-litter-soil feedbacks in common grass species are slightly negative and only marginally modified by litter exposed to insect herbivory

Climate change and human footprint increase insect defoliation across central boreal forests of Canada

Hundreds of billions of silent outbreaks: A historic outbreak record of the gall midge Schizomyia castanopsisae (Diptera: Cecidomyiidae) on the Izu Islands, Tokyo, Japan, and its potential mechanism

Contact Info

Product

Resources

About