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We quantified temporal dynamics of wood storage, input, and transport over a 24‐year period in adjacent old‐growth and second‐growth forested reaches in Mack Creek, a third‐order stream in the Cascade Range of Oregon. The standing stocks of large wood in the old‐growth reach exceeded those at the second‐growth reach by more than double the number of wood pieces and triple the wood volume. Annual inputs of large wood were highly variable. Wood numbers delivered into the old‐growth reach were 3× higher and wood volume 10× greater than in the second‐growth reach. The movement of number and volume of logs did not differ significantly between the two reaches over time. Less than 2% of the logs moved in most years, and the highest proportion moved in the year of the 1996 flood (9% in old growth and 22% in second growth). Most of the large wood aggregated as jams in both reaches. The second‐growth reach lacked major jams, but 29% of the logs in the old growth were in full‐channel spanning jams. Long‐term observations of annual storage, input, and movement reveal the temporal dynamics of wood rather than static representations of the characteristics of wood. Input events and transport of wood in Mack Creek were episodic and varied greatly over the 24‐year study, which illustrates one of the major challenges and opportunities for understanding the cumulative dynamics of wood in streams.
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Hubbard Brook Experimental Forest and Adirondack Mountains: In-stream large wood and riparian forest structure, 2002-2019
This dataset presents data on the in-stream large wood in 16 stream reaches in the Hubbard Brook Experimental Forest as well as the riparian forest structure and composition at these streams. It also provides data on the large wood in 13 stream reaches in old-growth forests in the Adirondack Mountains of New York.
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- PAR ID:
- 10573316
- Publisher / Repository:
- Environmental Data Initiative
- Date Published:
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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{"Abstract":["This data set includes spatially explicit mark-recapture data of the\nNorthern Spring Salamander (Gyrinophilus porphyriticus) collected during\nthe summer months (June \u2013 August) from downstream and upstream reaches\nin multiple streams in the Hubbard Brook Experimental Forest. Downstream\nreaches begin at the confluence with the Main Hubbard and extend\nupstream 500 meters and upstream reaches begin at the weir and extend\ndownstream 500 meters. Downstream reaches contain brook trout and\nupstream reaches do not. We used a robust design framework with\napproximately 9 surveys per reach each summer (3 primary occasions with\n3 secondary occasions each). Salamanders were captured by hand and\nmarked with either Visual Implant Elastomer and/or a PIT tag.\n These data were gathered as part of the Hubbard Brook Ecosystem Study\n(HBES). The HBES is a collaborative effort at the Hubbard Brook\nExperimental Forest, which is operated and maintained by the USDA Forest\nService, Northern Research Station.\n These data have been published in the following papers: \n Lowe WH, Addis\nBR, Smith MR, Davenport JM. The spatial structure of variation in\nsalamander survival, body condition and morphology in a headwater stream\nnetwork. Freshwater Biol. 2018;63:1287\u20131299.\nhttps://doi.org/10.1111/fwb.13133\n Lowe, W. H., and Addis, B. R.. 2019. Matching habitat choice and plasticity contribute to phenotype\u2013environment covariation in a stream salamander. Ecology 100( 5):e02661. 10.1002/ecy.2661 \n Lowe, W.H., et al. Hydrologic variability contributes to reduced survival through metamorphosis in a stream salamander. Proceedings of the National Academy of Sciences 2019; 116.39: 19563-19570.\n Bryant, A.R., Gabor, C.R., Swartz, L.K., Wagner, R., Cochrane, M.M., Lowe, W.H. Differences in corticosterone release rates of larval Spring Salamanders (Gyrinophilus porphyriticus) in response to native fish presence. Biology 2022; 11.484. https://doi.org/10.3390/biology11040484\n Addis, B.R., and W.H. Lowe. Environmentally associated variation in dispersal distance affects inbreeding risk in a stream salamander." The American Naturalist 2022."]}more » « less
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Abstract Cyclonic storms, or hurricanes, are expected to intensify as ocean heat energy rises due to climate change. Ecological theory suggests that tropical forest resistance to hurricanes should increase with forest age and wood density. However, most data on hurricane effects on tropical forests come from a limited number of well‐studied long‐term monitoring sites, restricting our capacity to evaluate the resistance of tropical forests to hurricanes across broad environmental gradients.In this study, we assessed whether forest age and aridity mediate the effects of hurricanes Irma and Maria in Puerto Rico, Vieques and Culebra islands. We leveraged functional trait data for 410 tree species, remotely sensed measurements of canopy height and cover, along with data on forest stand characteristics of 180 of 338 forest monitoring plots, each covering an area of 0.067 ha. The plots represent a broad mean annual precipitation (MAP) gradient from 701 to 4598 mm and a complex mosaic of forest age from 5 to around 85 years since deforestation.Hurricanes resulted in a 25% increase in basal area mortality rates, a 45% decrease in canopy height and a 21% reduction in canopy cover. These effects intensified with forest age, even after considering proximity to the hurricane path. The links between forest age and hurricane disturbances were likely due the prevalence of tall canopies.Tall forest canopies were strongly linked with low community‐weighted wood density (WD). These characteristics were on average more common in moist and wet forests (MAP >1250 mm). Conversely, dry forests were dominated by short species with high wood density (WD > 0.6 g cm−3) and did not show significant increases in basal area mortality rates after the hurricanes.Synthesis. Our findings show that selection towards drought‐tolerant traits across aridity gradients, such as short stature and dense wood, enhances resistance to hurricanes. However, forest age modulated responses to hurricanes, with older forests being less resistant across the islands. This evidence highlights the importance of considering the intricate links between ecological succession and plant function when forecasting tropical forests’ responses to increasingly strong hurricanes.more » « less
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