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Evidence-based responses to climate change by society require operational and sustained information including biophysical indicator systems that provide up-to-date measures of trends and patterns against historical baselines. Two key components linking anthropogenic climate change to impacts on socio-ecological systems are the periodic inter- and intra-annual variations in physical climate systems (seasonality) and in plant and animal life cycles (phenology). We describe a set of national indicators that reflect sub-seasonal to seasonal drivers and responses of terrestrial physical and biological systems to climate change and variability at the national scale. Proposed indicators and metrics include seasonality of surface climate conditions (e.g., frost and freeze dates and durations), seasonality of freeze/thaw in freshwater systems (e.g., timing of stream runoff and durations of lake/river ice), seasonality in ecosystem disturbances (e.g., wildfire season timing and duration), seasonality in vegetated land surfaces (e.g., green-up and brown-down of landscapes), and seasonality of organismal life-history stages (e.g., timings of bird migration). Recommended indicators have strong linkages to variable and changing climates, include abiotic and biotic responses and feedback mechanisms, and are sufficiently simple to facilitate communication to broad audiences and stakeholders interested in understanding and adapting to climate change.

In this age of rapid biodiversity loss, we must continue to refine our approaches to describing variation in life on Earth. Combining knowledge and research tools from multiple disciplines is one way to better describe complex natural systems. Understanding plant community diversity requires documenting both pattern and process. We must first know which species exist, and where (i.e., taxonomic and biogeographic patterns), before we can determine why they exist there (i.e., ecological and evolutionary processes). Floristic botanists often use collections-based approaches to elucidate biodiversity patterns, while plant ecologists use hypothesis-driven statistical approaches to describe underlying processes. Because of these different disciplinary histories and research goals, floristic botanists and plant ecologists often remain siloed in their work. Here, using a case study from an urban greenway in Colorado, USA, we illustrate that the collections-based, opportunistic sampling of floristic botanists is highly complementary to the transect- or plot-based sampling of plant ecologists. We found that floristic sampling captured a community species pool four times larger than that captured using ecological transects, with rarefaction and non-parametric species estimation indicating that it would be prohibitive to capture the “true” community species pool if constrained to sampling within transects. We further illustrate that the discrepancy in species pool size between approaches led to a different interpretation of the greenway’s ecological condition in some cases (e.g., transects missed uncommon cultivated species escaping from nearby gardens) but not others (e.g., plant species distributions among functional groups were similar between species pools). Finally, we show that while using transects to estimate plant relative abundances necessarily trades off with a fuller assessment of the species pool, it is an indispensable indicator of ecosystem health, as evidenced by three non-native grasses contributing to 50% of plant cover along the highly modified urban greenway. We suggest that actively fostering collaborations between floristic botanists and ecologists can create new insights into the maintenance of species diversity at the community scale.

The foothills and shortgrass prairie ecosystems of Colorado, United States, have undergone substantial and sustained anthropogenic habitat change over the past two centuries. Riparian systems have been dramatically altered by agriculture, hydrological engineering, urbanisation and the introduction of non-native invasive species. In 2016, Denver Botanic Gardens began a restoration effort of Deer Creek which seeks to modify the hydrology of the creek by mimicking the effects of beaver dams with artificial structures. The site, owned by the US Army Core of Engineers and managed by Denver Botanic Gardens, had been the subject of previous botanical surveys. With the initiation of the restoration project, permanent transects were established along the stream and are sampled for ground vegetation richness and abundance, canopy cover, soil and stream conditions and aquatic macroinvertebrate community makeup on an annual basis. To provide a means for tracking any post-intervention changes in the riparian ecosystem, this resource reports all recorded occurrences and measurements, along with methodologies and motivations from past and current surveys in the form of a sampling event dataset. The current project and past surveys document 382 plant taxa and 157 aquatic macroinvertebrate taxa. A total of 16304 occurrences and 7422 measurements are included in the resource. Occurrence and measurement data taken from transects provide a means to measure species abundance, ground cover and other biotic and abiotic characteristics relevant to assessing the effects of hydrological restoration on riparian plant communities.

Phenology is one of the best indicators to observe plant responses to climate change and predict future changes in plant communities. Choosing indicator species to monitor biological responses to climate change may be improved if herbarium specimens are combined with ongoing monitoring efforts to understand phenological responses over longer periods. We analyzed herbarium specimen data from Colorado’s alpine region, as alpine areas are predicted to be especially sensitive to climate change. We assessed phenological patterns in relation to temperature and precipitation for 287 species and growing degree days (GDD) for 235 species. Average low temperature, maximum GDD, and average precipitation increased over the study period. As temperature and GDD increased, phenology advanced, but as precipitation increased, phenology was delayed. Even with this variability of environmental responses, a significant trend of earlier flowering appeared when all species were analyzed together. Of the species that showed significantly earlier flowering dates, they advanced on average more than 39 days over the 61 years of the study. When assessing only specimens of species monitored in a national program (USA National Phenology Network), we found that these species showed similar trends to the entire dataset. When selecting species for ongoing monitoring efforts, herbarium specimens are an important resource to incorporate historical patterns into assessments of climate change and phenological drivers.

International audience; Parasites and pathogens are increasingly recognized as significant drivers of ecological and evolutionary change in natural ecosystems. Concurrently, transmission of infectious agents among human, livestock, and wildlife populations represents a growing threat to veterinary and human health. In light of these trends and the scarcity of long‐term time series data on infection rates among vectors and reservoirs, the National Ecological Observatory Network (NEON) will collect measurements and samples of a suite of tick‐, mosquito‐, and rodent‐borne parasites through a continental‐scale surveillance program. Here, we describe the sampling designs for these efforts, highlighting sampling priorities, field and analytical methods, and the data as well as archived samples to be made available to the research community. Insights generated by this sampling will advance current understanding of and ability to predict changes in infection and disease dynamics in novel, interdisciplinary, and collaborative ways.

© 2016 Elmendorf et al. Phenology is an integrative science that comprises the study of recurring biological activities or events. In an era of rapidly changing climate, the relationship between the timing of those events and environmental cues such as temperature, snowmelt, water availability, or day length are of particular interest. This article provides an overview of the observer-based plant phenology sampling conducted by the U.S. National Ecological Observatory Network (NEON), the resulting data, and the rationale behind the design. Trained technicians will conduct regular in situ observations of plant phenology at all terrestrial NEON sites for the 30-yr life of the observatory. Standardized and coordinated data across the network of sites can be used to quantify the direction and magnitude of the relationships between phenology and environmental forcings, as well as the degree to which these relationships vary among sites, among species, among phenophases, and through time. Vegetation at NEON sites will also be monitored with tower-based cameras, satellite remote sensing, and annual high-resolution airborne remote sensing. Ground-based measurements can be used to calibrate and improve satellite-derived phenometrics. NEON's phenology monitoring design is complementary to existing phenology research efforts and citizen science initiatives throughout the world and will produce interoperable data. By collocating plant phenology observations with a suite of additional meteorological, biophysical, and ecological measurements (e.g., climate, carbon flux, plant productivity, population dynamics of consumers) at 47 terrestrial sites, the NEON design will enable continental-scale inference about the status, trends, causes, and ecological consequences of phenological change.

Effective management of invasive species spread requires understanding the potential of exotic species to colonize different habitat types. In the case of Bromus tectorum, colonization potential includes persisting in variable environments via phenotypic plasticity or via genetic variation. Bromus tectorum L. (cheatgrass or downy brome) is a highly invasive, self-pollinating, winter annual grass that was introduced to the intermountain region of North America around 1890 and expanded to its modern range within 40 years. Common garden studies have helped shed light on outcrossing frequency, microsite effects on establishment and growth, traits that could confer invasiveness, and variation in germination, morphology, and physiology. Here, we review the evidence for existing local adaptation and phenotypic plasticity in B. tectorum in its invaded range along with the potential for responses to climate change and discuss implications of both for its success as an invader and future management. All of these studies show that B. tectorum can tolerate a wide range of habitats as the result of genetic variation among populations, a range of locally adapted ecotypes, and phenotypic plasticity. The success of B. tectorum could be due to its ability to maintain fitness in both high-quality and marginal environments.

Prior molecular work using ITS and chloroplast sequence data revealed that the endemic Lithophragma trifoliatum and the broad-ranging L. parviflorum form a tight clade with a third species, L. affine. We used AFLPs to assess the fine scale relationship of these three species from populations where their distributions overlap in northern California. Our results revealed two groups of L. trifoliatum, one nested within a group of L. affine and L. parviflorum and the other grouped with other populations of L. parviflorum, contrary to predictions based on plant morphology alone. The morphological pattern was not supported by the molecular data, suggesting that pink flowers evolved more than once, concurrently with other floral traits such as size and nectary length. It is also possible that this pattern is due to recent evolution or gene flow between the two color morphs. The possible ecological importance of these differences in floral traits (e.g., for pollination) warrants further study, as well as...