Habitat fragmentation affects plant-arthropod interactions through connectivity loss and edge effects
Data files
Dec 16, 2025 version files 158.97 KB
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CARBEL-arthropods.csv
28.83 KB
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CARBEL-floral.csv
108.47 KB
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CARBEL-seeds.csv
11.97 KB
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Patch_type.csv
555 B
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README.md
9.14 KB
Abstract
Habitat fragmentation is widespread globally, but the effects of fragmentation on populations and communities are often unclear. Because species responses to fragmentation are interdependent, examining how fragmentation alters species interactions may clarify community responses to fragmentation. In a large, replicated fragmentation experiment, we tested the effects of inter-patch connectivity, patch-scale edge-to-area ratio, and within-patch distance from an edge on multiple co-occurring plant-arthropod interactions and pollination rate (measured by fruit-flower ratio). Using experimentally planted populations of the sandy-woods chaffhead Carphephorus bellidifolius, we measured three plant arthropod-interactions: plant-pollinator interactions, plant-florivore interactions, and plant-spider interactions (predators of pollinators). Connectivity increased pollinator visitation, highlighting the significance of connectivity for pollinator foraging. Across all arthropod groups, connectivity and edge-to-area ratio affected visitation more than distance from an edge. Despite the strong impact of connectivity on plant-pollinator interactions, connectivity had no effect on fruit-flower ratio, indicating that other local factors may be more significant for pollination and seed set. Taken together, we provide experimental evidence that multiple plant-arthropod interactions are altered by habitat fragmentation through connectivity loss and increased edge-to-area ratio. Incorporating species interactions into fragmentation research will strengthen understanding of the mechanisms by which fragmentation alters populations and communities.
Contact: Katherine Hulting, hultingk@msu.edu
File name: CARBEL-arthropods.csv
Each row contains data for one interaction on one plant.
| Variable | Description |
|---|---|
| block | Site name (8, 10, 52, 57, 53N, 53S, or 54S) |
| patch | Patch Identifier ( B = Connected, C = Wing or Rectangle, D = Wing or Rectangle, E = Wing or Rectangle (labeled clock-wise from patch B) |
| corner | Corner of patch where plant is located. With back to patch A, I = top left, II = top right, III = bottom left, IV = bottom right |
| distance | Categorical distance of plant from edge. 0 = closest to edge, 3 = furthest from edge |
| plant_ID | Unique ID for each focal plant |
| sampling_round | Sampling round of observation (1-4) |
| temp | Air temperature during observation (C) |
| wind | Windspeed during observation (km/hr) |
| cloud_cover | Percent cloud cover during observation |
| date | Date of observation (mm/dd/yyyy) |
| start_time | Start time of survey in which observation took place (hh:mm) |
| visitor_species | Species identification to lowest taxanomic identification. 0 = no observation made during survey |
| visitor_type | Catagorization of observation as pollinator, spider, or florivore. 0 = no observation made during survey |
| edge_type | Catagorization of distance to edge as edge (0-10m) or interior (>10m) |
File name: CARBEL-floral.csv
Each row contains data for one species observed during a floral survey. All floral species were surveyed within 5m of a focal Carphephorus plant.
| Variable | Description |
|---|---|
| block | Site name (8, 10, 52, 57, 53N, 53S, or 54S) |
| patch | Patch Identifier ( B = Connected, C = Wing or Rectangle, D = Wing or Rectangle, E = Wing or Rectangle (labeled clock-wise from patch B) |
| corner | Corner of patch where plant is located. With back to patch A, I = top left, II = top right, III = bottom left, IV = bottom right |
| distance | Categorical distance of plant from edge. 0 = closest to edge, 3 = furthest from edge |
| plant_ID | Unique ID for each focal plant |
| sampling_round | Sampling round of observation (1-4) |
| date | Date of observation (mm/dd/yyyy) |
| start_time | Start time of survey in which observation took place (hh:mm) |
| focal_count | Number of flowering inflorescences on focal plant at time of survey |
| floral_species | Species identification of flowering plant within 5m of focal plant |
| floral_code | Six letter code of species name |
| number_individuals | Number of flowering individuals of one species in survey plot |
| avg_1-avg_10 | Count of flowers on an individual plant. Number of flowers were counted for 10 individuals per species. NA indicates no count, due to less than 10 individuals present in the plot |
File name: CARBEL-seeds.csv
Each row contains data for one inflorescence on one focal plant (up to 3 inflorescences/plant)
| Variable | Description |
|---|---|
| block | Site name (8, 10, 52, 57, 53N, 53S, or 54S) |
| patch | Patch Identifier ( B = Connected, C = Wing or Rectangle, D = Wing or Rectangle, E = Wing or Rectangle (labeled clock-wise from patch B) |
| corner | Corner of patch where plant is located. With back to patch A, I = top left, II = top right, III = bottom left, IV = bottom right |
| distance | Categorical distance of plant from edge. 0 = closest to edge, 3 = furthest from edge |
| plant_ID | Unique ID for each focal plant |
| seed_head | Letter assigned to one of three seed heads per plant (A, B, C) |
| collection_date | Date of seed head collection from plant (mm/dd/yyyy) |
| count_date | Date that seeds were inspected and counted (mm/dd/yyyy) |
| viable | Number of achenes containing a viable seed |
| nonviable | Number of achenes not containing a viable seed |
| no_predation | Number of achenes with evidence of predispersal seed predation damage |
File name: Patch_type.csv
Each row contains data for one patch per block in experimentally fragmented landscapes.
| Variable | Description |
|---|---|
| Block | Site name (8, 10, 52, 57, 53N, 53S, or 54S) |
| Patch | Patch Identifier (B = Connected, C = Wing or Rectangle, D = Wing or Rectangle, E = Wing or Rectangle (labeled clock-wise from patch B) |
| Type | Corresponding patch type (Connected, Winged, Rectangular) |
