Geology Reports⌕ Search

USGS · 70196769

Macroscale patterns of synchrony identify complex relationships among spatial and temporal ecosystem drivers

Abstract

Ecology has a rich history of studying ecosystem dynamics across time and space that has been motivated by both practical management needs and the need to develop basic ideas about pattern and process in nature. In situations in which both spatial and temporal observations are available, similarities in temporal behavior among sites (i.e., synchrony) provide a means of understanding underlying processes that create patterns over space and time. We used pattern analysis algorithms and data spanning 22–25 yr from 601 lakes to ask three questions: What are the temporal patterns of lake water clarity at sub‐continental scales? What are the spatial patterns (i.e., geography) of synchrony for lake water clarity? And, what are the drivers of spatial and temporal patterns in lake water clarity? We found that the synchrony of water clarity among lakes is not spatially structured at sub‐continental scales. Our results also provide strong evidence that the drivers related to spatial patterns in water clarity are not related to the temporal patterns of water clarity. This analysis of long‐term patterns of water clarity and possible drivers contributes to understanding of broad‐scale spatial patterns in the geography of synchrony and complex relationships between spatial and temporal patterns across ecosystems.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Noah R. Lottig, Pang-Ning Tan, Tyler Wagner, Kendra Spence Cheruvelil, Patricia A. Soranno, Emily H. Stanley, Caren E. Scott, Craig A. Stow, Shuai Yuan. 2017-12-13. Macroscale patterns of synchrony identify complex relationships among spatial and temporal ecosystem drivers. https://doi.org/10.1002/ecs2.2024

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related USGS reports

Fire regime shift reveals 17th century socio-ecological change in the Rio Grande del Norte National Monument, New Mexico

Humans have influenced ecosystems for millennia, and social changes can have notable ecological effects. Recent human influence on ecosystems is exemplified by the collapse of fire regimes circa 1900 in the western United States due to increased grazing, fire suppression, and declining Indigenous fire use. Climate can also drive fire regime changes, which is reflected by increasing area burned across the West in recent decades associated with warming and increased aridity. In the southwestern United States during the mid-1600s, large social changes accompanied Spanish colonization. These changes included increases in domestic livestock (e.g., sheep and horses), declines of Indigenous populations and cultural burning, and exploitation of Puebloans that led to the 1680 Pueblo Revolt, an Indigenous uprising that expelled Spanish colonizers for 12 years. The ecological effects of these large social changes are not well studied. The goal of this study was to use tree-ring fire histories to investigate fire dynamics of a sagebrush-dominated landscape in the Rio Grande del Norte National Monument (RGDN) in northern New Mexico, including the effects of historical social and climatic changes. We reconstructed fire history on four forested mountains that rise above the sagebrush/grass plateau. We asked: (1) What was the pre-1900 fire frequency, season, and fire–climate relationship in the RGDN? (2) Was there evidence for fire spread in the sagebrush/grass flats between the mountains? and (3) Did regional social or climate changes influence fire regimes? From 1400 to 1679, we found frequent fire within forests (8–12-year median fire intervals [mfi]) and potential evidence of spreading fire through the sagebrush/grass ecosystem based on greater-than-expected intermountain fire synchrony. However, beginning in the mid-1600s and continuing after the Pueblo Revolt of 1680, there was (1) a significant decline in fire frequency, including 38–166-year mfi and no fire for >350 years at two sites; and (2) only one synchronous fire between mountains. During this 17th century period of socio-ecological change there was no persistent shift in climate. We propose that reduced Indigenous ignitions and increased domestic grazing, which reduced herbaceous fuels and fire spread, are likely causes of the extraordinary early and persistent reduction in fire.

New Mexico↗

Climate-driven changes in wetland hydroperiods predict losses in habitat suitability for amphibian breeding

Environmental regimes are shifting with accelerating climate change, disrupting interactions between species and ecosystems shaped by the climate of the pre-industrial era. Species assemblages that depend on a dynamic network of ephemeral and permanent habitats may be especially sensitive to changing climate, whereby shifting environmental regimes may limit species persistence in landscapes in ways not captured by species physiology or coarse habitat metrics alone. Here we forecasted the loss of montane and subalpine wetlands as breeding habitat for three amphibian species in the US Pacific Northwest, Ambystoma gracile , Ambystoma macrodactylum , and Rana cascadae . We combined historical and recent surveys to build occupancy models of current breeding habitat use. We combined these results with existing hydrological models to predict the loss of suitable breeding habitats by the 2080s due to increased wetland drying. We found that species-specific occupancy of wetlands used for reproduction was predicted by both abiotic (e.g., elevation, wetland area) and biotic (e.g., emergent vegetation) site-level characteristics. Among wetlands currently used for reproduction, we estimated that between 12% and 23% could become unsuitable for the aquatic phase of each species by the 2080s, with watershed-scale losses ranging from 0% to 80%. This suggests that wetland habitat loss could limit the persistence of these species in the Pacific Northwest, though impacts are expected to vary across landscapes. More broadly, we demonstrate a novel approach to quantifying species climate change vulnerability that can be used to identify areas of both risk and resilience in changing landscapes and help to prioritize the application of practical conservation solutions in areas of greatest need.

Washington↗

Sex-specific reproductive investment and survival of adult Atlantic salmon kelts across multiple dams

In adult Atlantic salmon, individual variation in migration and movement within rivers during spawning (i.e., reproductive movement, RM) is an important component of overall reproductive investment that may influence subsequent survival and repeat spawning. We test the cost-of-reproduction hypothesis—which states that increased reproductive investment decreases survival—by first quantifying individual RM of landlocked Atlantic salmon and then evaluating how RM, sex, and dams influence outmigration survival. Consistent with sexual selection for male mobility, male RM was ~4 times greater than that of females: they moved further, were more exploratory, visited a tributary more, went further upstream, and spent longer in the river. Results provide mixed support for a cost of RM on outmigration survival: individuals (inclusive of both sexes) that abandoned spawning and migrated downstream (i.e., “fallbacks”) survived 3.5-fold better than those that spawned (supporting an overall cost-of reproduction). However, males (with higher RM) had 2.8 times higher survival than females, and among males there was no effect of RM on survival (not-supporting a cost-of-RM). The most influential factor on survival was dam interactions, which reduced per-kilometer survival 18-fold relative to migration within free-flowing reaches. Documenting male-biased survival was unexpected given the (1) high RM of males and (2) that most prior studies find higher outmigration survival of female Atlantic salmon. We highlight how dams exacerbate the already high costs of reproduction in Atlantic salmon, which has important implications for contemporary evolution of behavioral tradeoffs.

Vermont↗