Ecosystem Metrics Research Articles

Description and evaluation of the Diat-HadOCC model v1.0: the ocean biogeochemical component of HadGEM2-ES

Abstract. The Diat-HadOCC model (version 1.0) is presented. A simple marine ecosystem model with coupled equations representing the marine carbon cycle, it formed the ocean biogeochemistry sub-model in the Met Office's HadGEM2-ES Earth system model. The equations are presented and described in full, along with the underlying assumptions, and particular attention is given to how they were implemented for the CMIP5 simulations. Results from the CMIP5 historical simulation (particularly those for the simulated 1990s) are shown and compared to data: dissolved nutrients and dissolved inorganic carbon, as well as biological components, productivity and fluxes. Where possible, the amplitude and phase of the predicted seasonal cycle are evaluated. Since the model was developed to explore and predict the effects of climate change on the marine ecosystem and marine carbon cycle, the response of the model to the RCP8.5 future scenario is also shown. While the model simulates the historical and current global annual mean air–sea CO2 flux well and is consistent with other modelling studies about how that flux will change under future scenarios, several of the ecosystem metrics are less well simulated. The total chlorophyll is higher than observations, while the primary productivity is just below the estimated range. In the CMIP5 simulations certain parameter choices meant that the diatoms and the misc-phytoplankton state variables behave more similarly than they should, and the surface dissolved silicate concentration drifts to excessively high levels. The main structural problem with the model is shown to be the iron sub-model.

Ten years of pulling: Ecosystem recovery after long‐term weed management in Garry oak savanna

AbstractEcosystem restoration is the practice of assisting recovery in degraded ecological communities. The aims of restoration are typically broad, involving the reinstatement of composition, structure, function, and resilience to disturbances. One common restoration tactic in degraded urban systems is to control invasive species, relying on passive restoration for further ecosystem‐level recovery. Here, we test whether this is an effective restoration strategy in Garry oak savanna, a highly threatened and ecologically important community in the North American Pacific Northwest. In urban savanna patches surrounding Victoria, British Columbia, community members have been actively removing aggressive invasive exotic species for over a decade. Based on vegetation surveys from 2007, we tested ecosystem changes in structure, composition, and resilience (i.e., functional redundancy and response diversity) across 10 years of varied management levels. We expected higher levels of invasive species management would correspond with improvements to these ecosystem metrics. However, management explained little of the patterns found over the 10‐year‐period. Woody encroachment was a complicated process of native and exotic invasion, while resilience and compositional changes were most closely tied with landscape connectivity. Thus, though invasive species management may prevent further degradation, active restoration strategies after removal are likely required for recovery of the ecosystem.

Model of trawlable area using benthic terrain and oceanographic variables—Informing survey design and habitat maps in the Gulf of Alaska

AbstractBottom trawl surveys provide fishery‐independent data on relative abundance and life history parameters for a wide range of marine taxa. Survey data are used to assess species distribution, biological interactions, and ecosystem structure and to manage marine resources. Not all bottom types or oceanographic conditions accommodate this survey method. We applied National Ocean Service hydrographic smooth sheets to evaluate physical attributes associated with habitat available to surveys. Random forests were used to evaluate the relative influence of benthic terrain and oceanographic predictors in determining accessibility to bottom trawl gear. We examined the marginal importance of each predictor, quantified the response gradient, and applied piecewise regression to determine threshold breakpoint values. Thresholds were used to develop predictive maps and distinguish untrawlable habitat at the scale of discrete towpaths and survey stations. Untrawlable habitat was associated with increased complexity in terrain, roughness, slope, surface curvature, substrate coarseness, current, and aspect. Maps of critical thresholds suggest different variables constrain the probability of a successful trawl in the nearshore, shelf, and continental slope. Overlay analysis of the model projection demonstrates the utility of archived smooth sheet data and identifies areas where higher resolution data might improve results. The model and maps produced in this analysis might be used to identify habitats available to and impacted by commercial trawl fisheries, inform the relative availability of various species and habitat types to bottom trawl surveys, evaluate bias in assessment indices and ecosystem metrics derived from survey data, and advance habitat‐specific biomass estimates.

Quantifying the effectiveness of shoreline armoring removal on coastal biota of Puget Sound.

Shoreline armoring is prevalent around the world with unprecedented human population growth and urbanization along coastal habitats. Armoring structures, such as riprap and bulkheads, that are built to prevent beach erosion and protect coastal infrastructure from storms and flooding can cause deterioration of habitats for migratory fish species, disrupt aquatic–terrestrial connectivity, and reduce overall coastal ecosystem health. Relative to armored shorelines, natural shorelines retain valuable habitats for macroinvertebrates and other coastal biota. One question is whether the impacts of armoring are reversible, allowing restoration via armoring removal and related actions of sediment nourishment and replanting of native riparian vegetation. Armoring removal is targeted as a viable option for restoring some habitat functions, but few assessments of coastal biota response exist. Here, we use opportunistic sampling of pre- and post-restoration data for five biotic measures (wrack % cover, saltmarsh % cover, number of logs, and macroinvertebrate abundance and richness) from a set of six restored sites in Puget Sound, WA, USA. This broad suite of ecosystem metrics responded strongly and positively to armor removal, and these results were evident after less than one year. Restoration responses remained positive and statistically significant across different shoreline elevations and temporal trajectories. This analysis shows that removing shoreline armoring is effective for restoration projects aimed at improving the health and productivity of coastal ecosystems, and these results may be widely applicable.

Variance and Rate‐of‐Change as Early Warning Signals for a Critical Transition in an Aquatic Ecosystem State: A Test Case From Tasmania, Australia

AbstractCritical transitions in ecosystem states are often sudden and unpredictable. Consequently, there is a concerted effort to identify measurable early warning signals (EWS) for these important events. Aquatic ecosystems provide an opportunity to observe critical transitions due to their high sensitivity and rapid response times. Using palaeoecological techniques, we can measure properties of time series data to determine if critical transitions are preceded by any measurable ecosystem metrics, that is, identify EWS. Using a suite of palaeoenvironmental data spanning the last 2,400 years (diatoms, pollen, geochemistry, and charcoal influx), we assess whether a critical transition in diatom community structure was preceded by measurable EWS. Lake Vera, in the temperate rain forest of western Tasmania, Australia, has a diatom community dominated by Discostella stelligera and undergoes an abrupt compositional shift at ca. 820 cal yr BP that is concomitant with increased fire disturbance of the local vegetation. This shift is manifest as a transition from less oligotrophic acidic diatom flora (Achnanthidium minutissimum, Brachysira styriaca, and Fragilaria capucina) to more oligotrophic acidic taxa (Frustulia elongatissima, Eunotia diodon, and Gomphonema multiforme). We observe a marked increase in compositional variance and rate‐of‐change prior to this critical transition, revealing these metrics are useful EWS in this system. Interestingly, vegetation remains complacent to fire disturbance until after the shift in the diatom community. Disturbance taxa invade and the vegetation system experiences an increase in both compositional variance and rate‐of‐change. These trends imply an approaching critical transition in the vegetation and the probable collapse of the local rain forest system.

Interspecific Interactions May Influence Reef Fish Management Strategies in the Gulf of Mexico

AbstractThis study highlights the importance of interspecific interactions among marine organisms and the effect that these trophic interactions have on the development of effective, adaptive management strategies for reef fishes in the Gulf of Mexico. To represent the spatially and temporally constrained, interspecific interactions among reef fishes we employ Atlantis (a spatially explicit, biogeochemical ecosystem model) as our simulation tool. Within Atlantis, we evaluate the performance of a two‐point harvest control rule (HCR) that adaptively increases fishing mortality linearly between upper and lower biomass thresholds based on the available biomass of the stocks. This example demonstrated the use of a “blanket” two‐point HCR that assessed the available biomass of several reef fish species (often co‐caught in fishing gear) both simultaneously and objectively. To estimate the impact of reef fish fishing on species abundance and biodiversity in the ecosystem, we examined four “low” and four “high” fishing mortality (F) scaler scenarios. All model projections are forward looking, representing a 50‐year time horizon (2010 to 2060). We evaluated the performance of the two‐point HCRs under the eight fishing mortality scenarios using ecosystem metrics that were previously found to robustly track changes in ecosystem function caused by fishing. We found that the lower F scenarios produced an ecologically distinct ecosystem state compared with the higher F scenarios, where relatively higher levels of fishing mortality (particularly on predators such as the deep Serranidae group) resulted in an increase in prey availability in later years of the simulation. This led to an increase in the overall productivity of the ecosystem over time and higher catch and biomass of most other reef fish groups at equilibrium (year 50). Our results suggest that a better understanding of interspecific interactions among targeted reef fishes and their prey is critical to developing ecosystem‐based management strategies for the Gulf of Mexico.

The Use of Marine Ecosystem Metrics for Preseason Forecasts of Salmon Harvest

The Use of Marine Ecosystem Metrics for Preseason Forecasts of Salmon Harvest

A condition metric for Eucalyptus woodland derived from expert evaluations.

The evaluation of ecosystem quality is important for land-management and land-use planning. Evaluation is unavoidably subjective, and robust metrics must be based on consensus and the structured use of observations. We devised a transparent and repeatable process for building and testing ecosystem metrics based on expert data. We gathered quantitative evaluation data on the quality of hypothetical grassy woodland sites from experts. We used these data to train a model (an ensemble of 30 bagged regression trees) capable of predicting the perceived quality of similar hypothetical woodlands based on a set of 13 site variables as inputs (e.g., cover of shrubs, richness of native forbs). These variables can be measured at any site and the model implemented in a spreadsheet as a metric of woodland quality. We also investigated the number of experts required to produce an opinion data set sufficient for the construction of a metric. The model produced evaluations similar to those provided by experts, as shown by assessing the model's quality scores of expert-evaluated test sites not used to train the model. We applied the metric to 13 woodland conservation reserves and asked managers of these sites to independently evaluate their quality. To assess metric performance, we compared the model's evaluation of site quality with the managers' evaluations through multidimensional scaling. The metric performed relatively well, plotting close to the center of the space defined by the evaluators. Given the method provides data-driven consensus and repeatability, which no single human evaluator can provide, we suggest it is a valuable tool for evaluating ecosystem quality in real-world contexts. We believe our approach is applicable to any ecosystem.

Improving performance of eco-industrial parks

Industrial Ecology hypothesises that networks of industries designed to be analogous to the structure and properties of food webs may approach a similarly sustainable and efficient state. Although ecology is the metaphor for designing Eco-Industrial Parks (EIPs), prior research has shown that EIPs are inferior in performance compared to natural ecosystems. One EIP design approach is to enlarge EIPs by combining two or more synergistic networks to create a larger, and hopefully more successful, synergistic mega-network. A quantitative analysis using structural ecosystem metrics is presented in this paper in order to test the potential of this approach. The findings indicate that merely enlarging EIPs by significant amounts may not be the best strategy for improving performance, but that special attention should be placed on the inclusion of key actors like agriculture that act like detritivores and promote more intense internal cycling.

Estimating uncertainty in ambient and saturation nutrient uptake metrics from nutrient pulse releases in stream ecosystems

AbstractNutrient spiraling is an important ecosystem process characterizing nutrient transport and uptake in streams. Various nutrient addition methods are used to estimate uptake metrics; however, uncertainty in the metrics is not often evaluated. A method was developed to quantify uncertainty in ambient and saturation nutrient uptake metrics estimated from saturating pulse nutrient additions (Tracer Additions for Spiraling Curve Characterization; TASCC). Using a Monte Carlo (MC) approach, the 95% confidence interval (CI) was estimated for ambient uptake lengths (Sw‐amb) and maximum areal uptake rates (Umax) based on 100,000 datasets generated from each of four nitrogen and five phosphorous TASCC experiments conducted seasonally in a forest stream in eastern Tennessee, U.S.A. Uncertainty estimates from the MC approach were compared to the CIs estimated from ordinary least squares (OLS) and non‐linear least squares (NLS) models used to calculate Sw‐amb and Umax, respectively, from the TASCC method. The CIs for Sw‐amb and Umax were large, but were not consistently larger using the MC method. Despite the large CIs, significant differences (based on non‐overlapping CIs) in nutrient metrics among seasons were found with more significant differences using the OLS/NLS vs. the MC method. We suggest that the MC approach is a robust way to estimate uncertainty, as the calculation of Sw‐amb and Umax violates assumptions of OLS/NLS while the MC approach is free of these assumptions. The MC approach can be applied to other ecosystem metrics that are calculated from multiple parameters, providing a more robust estimate of these metrics and their associated uncertainties.

Anthropogenic impacts drive niche and conservation metrics of a cryptic rattlesnake on the Colorado Plateau of western North America.

Ecosystems transition quickly in the Anthropocene, whereas biodiversity adapts more slowly. Here we simulated a shifting woodland ecosystem on the Colorado Plateau of western North America by using as its proxy over space and time the fundamental niche of the Arizona black rattlesnake (Crotalus cerberus). We found an expansive (= end-of-Pleistocene) range that contracted sharply (= present), but is blocked topographically by Grand Canyon/Colorado River as it shifts predictably northwestward under moderate climate change (= 2080). Vulnerability to contemporary wildfire was quantified from available records, with forested area reduced more than 27% over 13 years. Both ‘ecosystem metrics' underscore how climate and wildfire are rapidly converting the Plateau ecosystem into novel habitat. To gauge potential effects on C. cerberus, we derived a series of relevant ‘conservation metrics' (i.e. genetic variability, dispersal capacity, effective population size) by sequencing 118 individuals across 846 bp of mitochondrial (mt)DNA-ATPase8/6. We identified five significantly different clades (net sequence divergence = 2.2%) isolated by drainage/topography, with low dispersal (FST = 0.82) and small sizes (2Nef = 5.2). Our compiled metrics (i.e. small-populations, topographic-isolation, low-dispersal versus conserved-niche, vulnerable-ecosystem, dispersal barriers) underscore the susceptibility of this woodland specialist to a climate and wildfire tandem. We offer adaptive management scenarios that may counterbalance these metrics and avoid the extirpation of this and other highly specialized, relictual woodland clades.

Experimental Evidence of an Eco-evolutionary Feedback during Adaptive Divergence

Differences in how organisms modify their environment can evolve rapidly and might influence adaptive population divergence. In a common garden experiment in aquatic mesocosms, we found that adult stickleback from a recently diverged pair of lake and stream populations had contrasting effects on ecosystem metrics. These modifications were caused by both genetic and plastic differences between populations and were sometimes comparable in magnitude to those caused by the presence/absence of stickleback. Lake and stream fish differentially affected the biomass of zooplankton and phytoplankton, the concentration of phosphorus, and the abundance of several prey (e.g., copepods) and non-prey (e.g., cyanobacteria) species. The adult-mediated effects on mesocosm ecosystems influenced the survival and growth of a subsequent generation of juvenile stickleback reared in the same mesocosms. The prior presence of adults decreased the overall growth rate of juveniles, and the prior presence of stream adults lowered overall juvenile survival. Among the survivors, lake juveniles grew faster than co-occurring stream juveniles, except in mesocosm ecosystems previously modified by adult lake fish that were reared on plankton. Overall, our results provide evidence for reciprocal interactions between ecosystem dynamics and evolutionary change (i.e., eco-evolutionary feedbacks) in the early stages of adaptive population divergence.

An Integrated Coral Reef Ecosystem Model to Support Resource Management under a Changing Climate.

Millions of people rely on the ecosystem services provided by coral reefs, but sustaining these benefits requires an understanding of how reefs and their biotic communities are affected by local human-induced disturbances and global climate change. Ecosystem-based management that explicitly considers the indirect and cumulative effects of multiple disturbances has been recommended and adopted in policies in many places around the globe. Ecosystem models give insight into complex reef dynamics and their responses to multiple disturbances and are useful tools to support planning and implementation of ecosystem-based management. We adapted the Atlantis Ecosystem Model to incorporate key dynamics for a coral reef ecosystem around Guam in the tropical western Pacific. We used this model to quantify the effects of predicted climate and ocean changes and current levels of current land-based sources of pollution (LBSP) and fishing. We used the following six ecosystem metrics as indicators of ecosystem state, resilience and harvest potential: 1) ratio of calcifying to non-calcifying benthic groups, 2) trophic level of the community, 3) biomass of apex predators, 4) biomass of herbivorous fishes, 5) total biomass of living groups and 6) the end-to-start ratio of exploited fish groups. Simulation tests of the effects of each of the three drivers separately suggest that by mid-century climate change will have the largest overall effect on this suite of ecosystem metrics due to substantial negative effects on coral cover. The effects of fishing were also important, negatively influencing five out of the six metrics. Moreover, LBSP exacerbates this effect for all metrics but not quite as badly as would be expected under additive assumptions, although the magnitude of the effects of LBSP are sensitive to uncertainty associated with primary productivity. Over longer time spans (i.e., 65 year simulations), climate change impacts have a slight positive interaction with other drivers, generally meaning that declines in ecosystem metrics are not as steep as the sum of individual effects of the drivers. These analyses offer one way to quantify impacts and interactions of particular stressors in an ecosystem context and so provide guidance to managers. For example, the model showed that improving water quality, rather than prohibiting fishing, extended the timescales over which corals can maintain high abundance by at least 5–8 years. This result, in turn, provides more scope for corals to adapt or for resilient species to become established and for local and global management efforts to reduce or reverse stressors.

Global Invader Impact Network (GIIN): toward standardized evaluation of the ecological impacts of invasive plants

Terrestrial invasive plants are a global problem and are becoming ubiquitous components of most ecosystems. They are implicated in altering disturbance regimes, reducing biodiversity, and changing ecosystem function, sometimes in profound and irreversible ways. However, the ecological impacts of most invasive plants have not been studied experimentally, and most research to date focuses on few types of impacts, which can vary greatly among studies. Thus, our knowledge of existing ecological impacts ascribed to invasive plants is surprisingly limited in both breadth and depth. Our aim was to propose a standard methodology for quantifying baseline ecological impact that, in theory, is scalable to any terrestrial plant invader (e.g., annual grasses to trees) and any invaded system (e.g., grassland to forest). The Global Invader Impact Network (GIIN) is a coordinated distributed experiment composed of an observational and manipulative methodology. The protocol consists of a series of plots located in (1) an invaded area; (2) an adjacent removal treatment within the invaded area; and (3) a spatially separate uninvaded area thought to be similar to pre-invasion conditions of the invaded area. A standardized and inexpensive suite of community, soil, and ecosystem metrics are collected allowing broad comparisons among measurements, populations, and species. The method allows for one-time comparisons and for long-term monitoring enabling one to derive information about change due to invasion over time. Invader removal plots will also allow for quantification of legacy effects and their return rates, which will be monitored for several years. GIIN uses a nested hierarchical scale approach encompassing multiple sites, regions, and continents. Currently, GIIN has network members in six countries, with new members encouraged. To date, study species include representatives of annual and perennial grasses; annual and perennial forbs; shrubs; and trees. The goal of the GIIN framework is to create a standard yet flexible platform for understanding the ecological impacts of invasive plants, allowing both individual and synthetic analyses across a range of taxa and ecosystems. If broadly adopted, this standard approach will offer unique insight into the ecological impacts of invasive plants at local, regional, and global scales.

Temporal Trends of Ecosystem Development on Different Site Types in Reclaimed Boreal Forests

Forest development after land reclamation in the oil sands mining region of northern Alberta, Canada was assessed using long-term monitoring plots from both reclaimed and natural forests. The metrics of ecosystem development analyzed included measures of plant community structure and composition and soil nutrient availability. Early seral reclamation plots were grouped by site type (dry and moist-rich) and age categories, and these were compared with mature natural forests. There were few significant differences in ecosystem metrics between reclamation site types, but natural stands showed numerous significant differences between site types. Over time, there were significant changes in most plant community metrics such as species richness and cover of plant community groups (e.g., forbs, shrubs, and non-native species), but these were still substantially different from mature forests 20 years after reclamation. Available soil nitrogen did not change over time or by reclamation site type but available soil phosphorus did, suggesting that phosphorus may be a more suitable indicator of ecosystem development. The significant temporal changes in these reclaimed ecosystems indicate that studies of ecosystem establishment and development on reclaimed areas should be conducted over the long-term, emphasizing the utility of monitoring using long-term plot networks.

Rapid ecosystem response to restoration in an urban stream

Stream restoration seeks to re-establish ecological structure and function of river systems, and understanding its ecological consequences is a current focus of stream ecology. To characterize the short-term ecosystem response to restoration in an urbanized Pacific Northwest stream, we measured whole-system ammonium and phosphorus uptake, benthic and drifting aquatic insects, and fish community composition before and after restoration. We predicted that (1) nutrient demand would temporarily decrease ammonium and phosphorus concentrations, (2) periphyton accrual would structure the insect consumer response, and (3) restoration would change the fish community. After restoration, nutrient demand for ammonium and phosphorus temporarily increased to levels that have rarely been reported, but demand for both recovered to background levels within 35 days. Aquatic insect density tracked rapid periphyton accrual after restoration, and benthic insect density stabilized in less than a month whereas composition continued changing for 10 weeks. Within 11 months, the fish community returned to its pre-restoration composition dominated by non-native eastern brook trout (Salvelinus fontinalis). Restoration did not alter the community and ecosystem metrics we studied, but this urban stream underwent rapid succession during restoration-induced disturbance, perhaps because urban streams have resilient communities well-suited to rapid recovery.

Extinction and invasion do not add up in noisy dynamic ecological networks

Species extinction and invasion concurrently affect the composition and properties of ecological communities, yet their effects have largely been studied separately, and with more focus on species and ecological functional groups than the whole-community level. We adopted a dynamic ecological network approach to compare the effects of simultaneous single-species primary extinction and invasion on a set of ecosystem metrics to the effects of extinction and invasion in isolation. We also investigated the relationship between the impact and reversibility of extinction or invasion through reintroduction or eradication, respectively. We used Monte Carlo simulations of bioenergetic ecological network models that combined trophic and mutualistic interactions, contained either prey-dependent or ratio-dependent trophic functional responses, and incorporated either white or pink environmental stochasticity. As the separate extinction or invasion impact increased, the simultaneous extinction–invasion impact increased but was decreasingly additive of the two separate impacts, across all ecosystem metrics. Greater extinction or invasion impact was associated with lower reversibility for most model types and ecosystem metrics. There were also systematic differences between models with prey- and ratio-dependent functional responses. These results highlight the importance of considering the combined effects of extinction and invasion in ecological studies, management and restoration.

Lack of eutrophication in a tallgrass prairie ecosystem over 27 years.

Many North American grasslands are receiving atmospheric nitrogen (N) deposition at rates above what are considered critical eutrophication thresholds. Yet, potential changes in grassland function due to anthropogenic N deposition are poorly resolved, especially considering that other dynamic factors such as land use and precipitation can also affect N availability. To better understand whether elevated N deposition has altered ecosystem structure or function in North American grasslands, we analyzed a 27-year record of ecophysiological, community, and ecosystem metrics for an annually burned Kansas tallgrass prairie. Over this time, despite increasing rates of N deposition that are within the range of critical loads for grasslands, there was no evidence of eutrophication. Plant N concentrations did not increase, soil moisture did not decline, forb diversity did not decline, and the relative abundance of dominant grasses did not shift toward more eutrophic species. Neither aboveground primary productivity nor N availability to plants increased. The fates of deposited N in grasslands are still uncertain, and could include management losses through burning and grazing. However, evidence from this grassland indicates that eutrophication of North American grassland ecosystems is not an inevitable consequence of current levels of N deposition.

Ignoring discards biases the assessment of fisheries' ecological fingerprint

Understanding the pressures of fisheries on the ecosystem is crucial for effective management. Fishery removals, or catch, are composed of both landings and discards. However, the use of discards data in studies investigating the effect of the fishing pressures is sparse. Here, we explore the individual contribution of both these catch components to the overall pressure of fisheries on the ecosystem metrics. Using Irish observer data, we compare the linear relationship between several ecological metrics calculated for landings and discards with those of catch. Our results show that in fisheries with high discarding rates, discards can drive the fisheries' ecological fingerprint and highlight the need to rectify landings-based estimates to make them representative of those of catch in order to gain a robust picture of the impact of fisheries.

Effect of the current major insect outbreaks on decadal phenological and LAI trends in southern Rocky Mountain forests

Remote sensing is a valuable tool for monitoring the impact of landscape-scale disturbances on ecosystem structure and function. We explore the impact of the ongoing insect outbreaks (Dendroctonus ponderosae, D. rufipennis, and Ips spp.) on southern Rocky Mountain forests, with the goal of assessing the sensitivity of leaf area index (LAI) and phenology metrics to different disturbance severities. Specifically, we investigate the influence of the outbreaks on two important ecosystem metrics, LAI, and phenology (e.g. green-up date, green-up speed, amplitude, etc.). Both were assessed via MODIS: 1000 m LAI (MOD15A2) and 250 m NDVI (MYD13Q1) for the phenology assessment. Trends (2002–2010) in phenology metrics and LAI were compared to different cumulative severities and timing of tree mortality, as determined from aerial surveys. Trends in phenology were significantly correlated with disturbance severity but with very low predictive power. This seems likely due to yearly variations in the onset of snow-fall and snow-melt, which dominate the phenologic signal at the regional scale of this study. Trends in LAI were associated more strongly with both disturbance severity and timing, with landscapes disturbed early in the observation period showing recovery (e.g. a positive trend) in LAI. The LAI, which is related to various vital ecosystem properties like water use and gas exchange, seems to be fairly resilient to even heavy mortality. Further work determining the relative contribution of the various functional groups (trees, shrubs, and grasses) to the LAI recovery is needed to better understand the implications of this large-scale, pervasive disturbance on forest structure and function.