The effect of landscape structure on insect herbivory and biodiversity: Implications for forest ecosystem services in the Monteregie, Québec
Bibliographic record
Abstract
Anthropogenic disturbances are fragmenting forested areas around the world, fundamentally changing the structure of landscapes in a manner that has poorly understood consequences for biodiversity, ecological processes, and ecosystem services. This lack of understanding makes it difficult for land managers to make optimal decisions that balance environmental benefits and costs of land use change. In this thesis, I address this gap in our understanding by using a combination of theoretical and empirical approaches to quantify how and when fragmentation affects ecosystem processes that have distinct impacts on forest ecosystem services. Specifically, I test the role that insect herbivory plays in mediating the effects of landscape structure on ecosystem services in forest ecosystems in the Montégerie in southwest Quebec. Insect herbivory is a good model system to test these effects because it is sensitive to landscape structure, can have strong effects on ecosystem services, and can be either beneficial or harmful depending on the herbivore species and the ecosystem context. In this thesis, I quantify the effects of landscape structure on insect herbivory and biodiversity, and assesses the implications of these effects for forest ecosystem services in four steps: 1) In the second chapter examine the known relationships between landscape structure, herbivory and ecosystem services through a semi-quantitative literature review and show that herbivory plays an important role mediating effects of connectivity on ecosystem services. The results of this review show assessing the mechanisms that regulate the response of insect herbivores to landscape structure would allow for better predictions regarding this process. 2) In the third chapter, I quantify the relationship between landscape structure and herbivory, and test potential mechanisms (i.e. predation pressure) driving the response, using a manipulative field experiment in the Montérégie. I find that landscape structure alone does not explain levels of herbivory, even though there was strong vertebrate predation pressure on herbivores that varied with landscape structure. Because these results show structure at the landscape scale does not explain patterns of herbivory, my next step was to determine whether insect herbivory is spatially heterogeneous at a finer scale. 3) In the fourth chapter, I measure the spatial heterogeneity of insect herbivory in remnant forest patches at both the landscape and patch level, quantifying herbivore damage on sugar maple trees at the edge, interior, and canopy of remnant forest patches that differ in size and connectivity. I find that patterns of herbivory are affected by the interaction of landscape and patch level sources of spatial heterogeneity. 4) Finally, to better understand the mechanism by which these finer scale patterns occur, I measure the effects of landscape structure and location within a forest patch (i.e., edge, interior, canopy) on arthropod functional and taxonomic biodiversity. I find that canopies of fragmented forest patches are important reservoirs of arthropod biodiversity, even in fragmented forest ecosystems. Human activities, such as fragmentation or restoration, continue to affect the structure of forest ecosystems, with unknown consequences for the ecosystem services provided by forests. My thesis advances our understanding of the effects of landscape structure on ecosystem services by using herbivory as a model system to provide a conceptual framework with which to balance the social and environmental costs and benefits associated with altering landscape structure.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.002 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.002 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".