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At least 451 records · Page 25Linked to original sources
USGS2017

Using colony monitoring devices to evaluate the impacts of land use and nutritional value of forage on honey bee health

Colony monitoring devices used to track and assess the health status of honey bees are becoming more widely available and used by both beekeepers and researchers. These devices monitor parameters relevant to colony health at frequent intervals, often approximating real time. The fine-scale record of hive condition can be further related to static or dynamic features of the landscape, such as weather, climate, colony density, land use, pesticide use, vegetation class, and forage quality. In this study, we fit commercial honey bee colonies in two apiaries with pollen traps and digital scales to monitor floral resource use, pollen quality, and honey production. One apiary was situated in low-intensity agriculture; the other in high-intensity agriculture. Pollen traps were open for 72 h every two weeks while scales recorded weight every 15 min throughout the growing season. From collected pollen, we determined forage quantity per day, species identity using DNA sequencing, pesticide residues, amino acid content, and total protein content. From scales, we determined the accumulated hive weight change over the growing season, relating to honey production and final colony weight going into winter. Hive scales may also be used to identify the occurrence of environmental pollen and nectar dearth, and track phenological changes in plant communities. We provide comparisons of device-derived data between two apiaries over the growing season and discuss the potential for employing apiary monitoring devices to infer colony health in the context of divergent agricultural land use conditions.

Agriculture↗
USGS2023

Buzzards Bay salt marshes: Vulnerability and adaptation potential

Salt marshes with lush grass meadows teeming with shorebirds are iconic features of the Buzzards Bay coast and provide opportunities for recreation, aesthetic enjoyment, as well as important environmental benefits. These productive coastal wetlands are important because they protect properties from storm surges, remove nutrients from the water and carbon from the atmosphere, and provide critical habitats for fish, shellfish, and birds. Found where the land meets the sea, salt marshes are naturally dynamic features that change with rising seas, waves, ice, and storms. In the past, humans purposely altered salt marshes by filling them to create buildable land or digging drainage ditches. These major alterations harmed marsh structure and health. In recent decades, however, marshes are degrading because of more diffuse and complex pressures such as nutrient pollution, sea level rise, major storms, and crab overgrazing. As a result, at many places along the East Coast, marshes have crumbling banks and large areas where the plants have died, leaving behind mudflats. The Buzzards Bay Coalition and the Buzzards Bay National Estuary Program began field monitoring of salt marshes around Buzzards Bay in 2019 to document changes (map below shows sites). We partnered with the U.S. Geological Survey and the Woodwell Climate Research Center to use aerial tools to investigate how different characteristics of the long-term marsh sites and their watersheds affect the marsh’s current health and likely future. This report brings together the results of on the ground monitoring with data from aerial imagery to look at marsh status at 12 long-term monitoring sites based on existing stressors, current marsh conditions, and potential for adaptation.

Massachusetts↗
USGS2015

Sea-level rise modeling handbook: Resource guide for coastal land managers, engineers, and scientists

Global sea level is rising and may accelerate with continued fossil fuel consumption from industrial and population growth. In 2012, the U.S. Geological Survey conducted more than 30 training and feedback sessions with Federal, State, and nongovernmental organization (NGO) coastal managers and planners across the northern Gulf of Mexico coast to evaluate user needs, potential benefits, current scientific understanding, and utilization of resource aids and modeling tools focused on sea-level rise. In response to the findings from the sessions, this sea-level rise modeling handbook has been designed as a guide to the science and simulation models for understanding the dynamics and impacts of sea-level rise on coastal ecosystems. The review herein of decision-support tools and predictive models was compiled from the training sessions, from online research, and from publications. The purpose of this guide is to describe and categorize the suite of data, methods, and models and their design, structure, and application for hindcasting and forecasting the potential impacts of sea-level rise in coastal ecosystems. The data and models cover a broad spectrum of disciplines involving different designs and scales of spatial and temporal complexity for predicting environmental change and ecosystem response. These data and models have not heretofore been synthesized, nor have appraisals been made of their utility or limitations. Some models are demonstration tools for non-experts, whereas others require more expert capacity to apply for any given park, refuge, or regional application. A simplified tabular context has been developed to list and contrast a host of decision-support tools and models from the ecological, geological, and hydrological perspectives. Criteria were established to distinguish the source, scale, and quality of information input and geographic datasets; physical and biological constraints and relations; datum characteristics of water and land components; utility options for setting sea-level rise and climate change scenarios; and ease or difficulty of storing, displaying, or interpreting model output. Coastal land managers, engineers, and scientists can benefit from this synthesis of tools and models that have been developed for projecting causes and consequences of sea-level change on the landscape and seascape.

Professional Paper↗
USGS2026

Decadal shifts in groundwater age detected by environmental tracers across California, USA

Groundwater age offers important insight into recharge, storage, and contamination risk. Although models predict age changes can be driven by pumping and climate variability, direct observational evidence remains limited. Here, we analyzed paired environmental tracer suites (tritium, carbon-14, and tritiogenic helium-3) collected a decade apart from 268 wells across California to assess the prevalence of groundwater age transience. Travel-time distribution models and statistical tests indicated age transience at 29% of sites, occurring most often in agricultural regions, such as the San Joaquin Valley and Southern Coast Ranges, where large carbon-14 changes coincided with substantial nitrate and chloride shifts. Sites with tritiogenic helium-3 data showed more frequent age transience, underscoring the value of multi-tracer data sets. These results provide the first regional evidence of widespread groundwater age change and a method for detecting changing water balances with implications for groundwater sustainability and water quality.

California↗
USGS2021

Emergent biogeochemical risks from Arctic permafrost degradation

The Arctic cryosphere is collapsing, posing overlapping environmental risks. In particular, thawing permafrost threatens to release biological, chemical and radioactive materials that have been sequestered for tens to hundreds of thousands of years. As these constituents re-enter the environment, they have the potential to disrupt ecosystem function, reduce the populations of unique Arctic wildlife and endanger human health. Here, we review the current state of the science to identify potential hazards currently frozen in Arctic permafrost. We also consider the cascading natural and anthropogenic processes that may compound the impacts of these risks, as it is unclear whether the highly adapted Arctic ecosystems have the resilience to withstand new stresses. We conclude by recommending research priorities to address these underappreciated risks.

Nature Climate Change↗
USGS2011

Excess nitrogen in the U.S. environment: Trends, risks, and solutions

It is not surprising that humans have profoundly altered the global nitrogen (N) cycle in an effort to feed 7 billion people, because nitrogen is an essential plant and animal nutrient. Food and energy production from agriculture, combined with industrial and energy sources, have more than doubled the amount of reactive nitrogen circulating annually on land. Humanity has disrupted the nitrogen cycle even more than the carbon (C) cycle. We present new research results showing widespread effects on ecosystems, biodiversity, human health, and climate, suggesting that in spite of decades of research quantifying the negative consequences of too much available nitrogen in the biosphere, solutions remain elusive. There have been important successes in reducing nitrogen emissions to the atmosphere and this has improved air quality. Effective solutions for reducing nitrogen losses from agriculture have also been identified, although political and economic impediments to their adoption remain. Here, we focus on the major sources of reactive nitrogen for the United States (U.S.), their impacts, and potential mitigation options. Sources: ??? Intensive development of agriculture, industry, and transportation has profoundly altered the U.S. nitrogen cycle. ??? Nitrogen emissions from the energy and transportation sectors are declining, but agricultural emissions are increasing. ??? Approximately half of all nitrogen applied to boost agricultural production escapes its intended use and is lost to the environment. Impacts: ??? Two-thirds of U.S. coastal systems are moderately to severely impaired due to nutrient loading; there are now approximately 300 hypoxic (low oxygen) zones along the U.S. coastline and the number is growing. One third of U.S. streams and two fifths of U.S. lakes are impaired by high nitrogen concentrations. ??? Air pollution continues to reduce biodiversity. A nation-wide assessment has documented losses of nitrogen-sensitive native species in favor of exotic, invasive species. ??? More than 1.5 million Americans drink well water contaminated with too much (or close to too much) nitrate (a regulated drinking water pollutant), potentially placing them at increased risk of birth defects and cancer. More research is needed to deepen understanding of these health risks. ??? Several pathogenic infections, including coral diseases, bird die-offs, fish diseases, and human diarrheal diseases and vector-borne infections are associated with nutrient losses from agriculture and from sewage entering ecosystems. ??? Nitrogen is intimately linked with the carbon cycle and has both warming and cooling effects on the climate. Mitigation Options: ??? Regulation of nitrogen oxide (NOX) emissions from energy and transportation sectors has greatly improved air quality, especially in the eastern U.S. Nitrogen oxide is expected to decline further as stronger regulations take effect, but ammonia remains mostly unregulated and is expected to increase unless better controls on ammonia emissions from livestock operations are implemented. ??? Nitrogen loss from farm and livestock operations can be reduced 30-50% using current practices and technologies and up to 70-90% with innovative applications of existing methods. Current U.S. agricultural policies and support systems, as well as declining investments in agricultural extension, impede the adoption of these practices. Society faces profound challenges to meet demands for food, fiber, and fuel while minimizing unintended environmental and human health impacts. While our ability to quantify transfers of nitrogen across land, water, and air has improved since the first publication of this series in 1997, an even bigger challenge remains: using the science for effective management policies that reduce climate change, improve water quality, and protect human and environmental health. ?? The Ecological Society of America.

Issues in Ecology↗
USGS2025

Climate change impacts and adaptation in U.S. Rocky Mountain high-elevation ecosystems

From a resource management perspective, climate change is considered to be one of the main threats to high-elevation ecosystems. However, these valuable ecosystems present unique challenges to climate change adaptation (actions in response to environmental change and its effects in a way that seeks to reduce harm) due to their rugged and remote characteristics. Within this context, we summarized literature on climate change impacts and adaptation actions across U.S. Rocky Mountain high-elevation ecosystems to address the important question: What are the knowledge gaps for climate change responses within this ecosystem that limit the ability of natural resource managers to perform successful climate change adaptation? In addressing this question, we focus specifically on the U.S. Rocky Mountains but also place regional conclusions for climate change adaptation in high-elevation ecosystems into a broader context. Overall, we found that the complex topography and temporally variable climate of mountains promote potential refugia that may buffer alpine obligate species in the near-term but also challenge resource managers to consider biological lags within this ecosystem.

Colorado, Idaho, Montana, New Mexico, Wyoming↗
USGS2012

Application of empirical predictive modeling using conventional and alternative fecal indicator bacteria in eastern North Carolina waters

Coastal and estuarine waters are the site of intense anthropogenic influence with concomitant use for recreation and seafood harvesting. Therefore, coastal and estuarine water quality has a direct impact on human health. In eastern North Carolina (NC) there are over 240 recreational and 1025 shellfish harvesting water quality monitoring sites that are regularly assessed. Because of the large number of sites, sampling frequency is often only on a weekly basis. This frequency, along with an 18–24 h incubation time for fecal indicator bacteria (FIB) enumeration via culture-based methods, reduces the efficiency of the public notification process. In states like NC where beach monitoring resources are limited but historical data are plentiful, predictive models may offer an improvement for monitoring and notification by providing real-time FIB estimates. In this study, water samples were collected during 12 dry (n = 88) and 13 wet (n = 66) weather events at up to 10 sites. Statistical predictive models for Escherichiacoli (EC), enterococci (ENT), and members of the Bacteroidales group were created and subsequently validated. Our results showed that models for EC and ENT (adjusted R2 were 0.61 and 0.64, respectively) incorporated a range of antecedent rainfall, climate, and environmental variables. The most important variables for EC and ENT models were 5-day antecedent rainfall, dissolved oxygen, and salinity. These models successfully predicted FIB levels over a wide range of conditions with a 3% (EC model) and 9% (ENT model) overall error rate for recreational threshold values and a 0% (EC model) overall error rate for shellfish threshold values. Though modeling of members of the Bacteroidales group had less predictive ability (adjusted R 2 were 0.56 and 0.53 for fecal Bacteroides spp. and human Bacteroides spp., respectively), the modeling approach and testing provided information on Bacteroidales ecology. This is the first example of a set of successful statistical predictive models appropriate for assessment of both recreational and shellfish harvesting water quality in estuarine waters.

North Carolina↗
USGS2019

The Aleutian Low – Beaufort Sea Anticyclone: A climate index for predicting the timing of springtime melt in the Pacific Arctic cryosphere

Early and late extremes in the timing of snowmelt have recently been observed in the Pacific Arctic. Subseasonal-to-seasonal forecasts of this timing are important for industry, environmental management and Arctic communities. In northern Alaska, the timing is influenced by the advection of marine air from the north Pacific by the Aleutian Low, modulated by high pressure centered in the Beaufort Sea. A new climate index that integrates their interaction could advance melt predictions. We define this index based on 850 hPa geopotential height at four fixed locations referred to as the Aleutian Low –Beaufort Sea Anticyclone (ALBSA). During positive ALBSA in May, advection of +0.5-1.5 K/day is observed through the Bering Strait. ALBSA is correlated with both snowmelt in northern Alaska and the onset of sea ice melt over the adjacent seas. ALBSA, therefore, may be suitable for monitoring the relevant circulation patterns and for developing predictive tools.

Geophysical Research Letters↗
USGS2022

Can we avert an Amazon tipping point? The economic and environmental costs

The Amazon biome is being pushed by unsustainable economic drivers towards an ecological tipping point where restoration to its previous state may no longer be possible. This degradation is the result of self-reinforcing interactions between deforestation, climate change and fire. We assess the economic, natural capital and ecosystem services impacts and trade-offs of scenarios representing movement towards an Amazon tipping point and strategies to avert one using the Integrated Economic-Environmental Modeling (IEEM) Platform linked with spatial land use-land cover change and ecosystem services modeling (IEEM + ESM). Our approach provides the first approximation of the economic, natural capital and ecosystem services impacts of a tipping point, and evidence to build the economic case for strategies to avert it. For the five Amazon focal countries, namely, Brazil, Peru, Colombia, Bolivia and Ecuador, we find that a tipping point would create economic losses of US$256.6 billion in cumulative gross domestic product by 2050. Policies that would contribute to averting a tipping point, including strongly reducing deforestation, investing in intensifying agriculture in cleared lands, climate-adapted agriculture and improving fire management, would generate approximately US$339.3 billion in additional wealth and a return on investment of US$29.5 billion. Quantifying the costs, benefits and trade-offs of policies to avert a tipping point in a transparent and replicable manner can support the design of regional development strategies for the Amazon biome, build the business case for action and catalyze global cooperation and financing to enable policy implementation.

Amazon↗
USGS2013

Wetlands serve as natural sources for improvement of stream ecosystem health in regions affected by acid deposition

For over 40 years, acid deposition has been recognized as a serious international environmental problem, but efforts to restore acidified streams and biota have had limited success. The need to better understand the effects of different sources of acidity on streams has become more pressing with the recent increases in surface water organic acids, or 'brownification' associated with climate change and decreased inorganic acid deposition. Here, we carried out a large scale multi-seasonal investigation in the Adirondacks, one of the most acid-impacted regions in the United States, to assess how acid stream producers respond to local and watershed influences and whether these influences can be used in acidification remediation. We explored the pathways of wetland control on aluminum chemistry and diatom taxonomic and functional composition. We demonstrate that streams with larger watershed wetlands have higher organic content, lower concentrations of acidic anions, and lower ratios of inorganic to organic monomeric aluminum, all beneficial for diatom biodiversity and guilds producing high biomass. Although brownification has been viewed as a form of pollution, our results indicate that it may be a stimulating force for biofilm producers with potentially positive consequences for higher trophic levels. Our research also reveals that the mechanism of watershed control of local stream diatom biodiversity through wetland export of organic matter is universal in running waters, operating not only in hard streams, as previously reported, but also in acid streams. Our findings that the negative impacts of acid deposition on Adirondack stream chemistry and biota can be mitigated by wetlands have important implications for biodiversity conservation and stream ecosystem management. Future acidification research should focus on the potential for wetlands to improve stream ecosystem health in acid-impacted regions and their direct use in stream restoration, for example, through stream rechanneling or wetland construction in appropriate hydrologic settings.

Global Change Biology↗
USGS2016

Toward more realistic projections of soil carbon dynamics by Earth system models

Soil carbon (C) is a critical component of Earth system models (ESMs), and its diverse representations are a major source of the large spread across models in the terrestrial C sink from the third to fifth assessment reports of the Intergovernmental Panel on Climate Change (IPCC). Improving soil C projections is of a high priority for Earth system modeling in the future IPCC and other assessments. To achieve this goal, we suggest that (1) model structures should reflect real-world processes, (2) parameters should be calibrated to match model outputs with observations, and (3) external forcing variables should accurately prescribe the environmental conditions that soils experience. First, most soil C cycle models simulate C input from litter production and C release through decomposition. The latter process has traditionally been represented by first-order decay functions, regulated primarily by temperature, moisture, litter quality, and soil texture. While this formulation well captures macroscopic soil organic C (SOC) dynamics, better understanding is needed of their underlying mechanisms as related to microbial processes, depth-dependent environmental controls, and other processes that strongly affect soil C dynamics. Second, incomplete use of observations in model parameterization is a major cause of bias in soil C projections from ESMs. Optimal parameter calibration with both pool- and flux-based data sets through data assimilation is among the highest priorities for near-term research to reduce biases among ESMs. Third, external variables are represented inconsistently among ESMs, leading to differences in modeled soil C dynamics. We recommend the implementation of traceability analyses to identify how external variables and model parameterizations influence SOC dynamics in different ESMs. Overall, projections of the terrestrial C sink can be substantially improved when reliable data sets are available to select the most representative model structure, constrain parameters, and prescribe forcing fields.

Global Biogeochemical Cycles↗
USGS2020

Storm impacts on phytoplankton community dynamics in lakes

In many regions across the globe, extreme weather events such as storms have increased in frequency, intensity, and duration due to climate change. Ecological theory predicts that such extreme events should have large impacts on ecosystem structure and function. High winds and precipitation associated with storms can affect lakes via short‐term runoff events from watersheds and physical mixing of the water column. In addition, lakes connected to rivers and streams will also experience flushing due to high flow rates. Although we have a well‐developed understanding of how wind and precipitation events can alter lake physical processes and some aspects of biogeochemical cycling, our mechanistic understanding of the emergent responses of phytoplankton communities is poor. Here we provide a comprehensive synthesis that identifies how storms interact with lake and watershed attributes and their antecedent conditions to generate changes in lake physical and chemical environments. Such changes can restructure phytoplankton communities and their dynamics, as well as result in altered ecological function (e.g., carbon, nutrient and energy cycling) in the short‐ and long‐term. We summarize the current understanding of storm‐induced phytoplankton dynamics, identify knowledge gaps with a systematic review of the literature, and suggest future research directions across a gradient of lake types and environmental conditions.

Global Change Biology↗
USGS2019

Integrating behavior and physiology into strategies for amphibian conservation

The amphibian decline crisis has been challenging to address because of the complexity of factors—and their multitude of interactive effects—that drive this global issue. Dissecting such complexity could benefit from strategies that integrate multiple disciplines and address the mechanistic underpinnings of population declines and extirpations. We examine how the disciplines of behavior and physiology could be used to develop conservation strategies for amphibians and identify eight research gaps that provide future directions for the emerging fields of conservation behavior and conservation physiology. We present two case studies on imperiled salamanders that show how studies of behavior and physiology may support amphibian conservation efforts. We found several applications of stress physiology to amphibian conservation, but long-term studies are needed to understand how stress ultimately affects individual fitness and population resilience. Additionally, multiple measures of physiological health are needed to provide a more holistic assessment of an individual’s overall condition. Previous behavioral and physiological studies have been instrumental for understanding how amphibians respond to habitat modification, pathogens and parasites, contaminants, and invasive species. Some behavior-based approaches to mitigating invasive species issues have been successful in short-term studies with individual species. However, widespread application of these tactics has not yet been integrated into conservation and management strategies for ecologically-similar species. A diversity of modeling approaches has enhanced understanding of how climate change may impact amphibian populations, but model predictions need empirical tests to provide conservation managers with workable approaches to multiple perturbations associated with global environmental change. We illustrate that behavior and physiology can have broad utility for amphibian conservation, but evidence is scant that such studies have actually been used to inform strategies for amphibian conservation and management.

Frontiers in Ecology and Evolution↗
USGS1997

Test-trench studies in the Amargosa Desert, southern Nevada: Results and application of information to landfill covers in arid environments

As arid sites in the western United States are increasingly sought for disposal of the Nation's hazardous wastes and as volumes of locally generated wastes increase, concern about the potential effect of contaminants on environmental quality is being raised. Studies at the U.S. Geological Survey's Amargosa Desert research site near Beatty, Nevada are being done to evaluate mechanisms that can affect waste isolation in an arid environment. Precipitation at the site averages about 108 mm yr -1 . Results have shown that, under undisturbed conditions, the naturally stratified soils in combination with native plants are effective in limiting the potential for percolation of precipitation. Under nonvegetated waste-site conditions, data indicated the accumulation and shallow, but continued, penetration of infiltrated water, However, water potentials below the test trenches and below the 2-m depth for nonvegetated soil indicated the persistence of an upward driving force for water flow during the 5-yr test period. General trends in trench-cover subsidence suggested a positive relation with cumulative precipitation, but subsidence did not appear to have a measurable effect on the water balance. Erosion rates were inversely related to near-surface rock-fragment content. Results suggest that the ultimate fate of contaminants buried at properly managed solid-waste sites may be determined largely by the interactions among climate and the surface-cover features of the disposal facility, and how these factors change with time.

Nevada↗
USGS2017

Patterns of distribution, abundance, and change over time in a subarctic marine bird community

Over recent decades, marine ecosystems of Prince William Sound (PWS), Alaska, have experienced concurrent effects of natural and anthropogenic perturbations, including variability in the climate system of the northeastern Pacific Ocean. We documented spatial and temporal patterns of variability in the summer marine bird community in relation to habitat and climate variability using boat-based surveys of marine birds conducted during the period 1989–2012. We hypothesized that a major factor structuring marine bird communities in PWS would be proximity to the shoreline, which is theorized to relate to aspects of food web structure. We also hypothesized that shifts in physical ecosystem drivers differentially affected nearshore-benthic and pelagic components of PWS food webs. We evaluated support for our hypotheses using an approach centered on community-level patterns of spatial and temporal variability. We found that an environmental gradient related to water depth and distance from shore was the dominant factor spatially structuring the marine bird community. Responses of marine birds to this onshore-offshore environmental gradient were related to dietary specialization, and separated marine bird taxa by prey type. The primary form of temporal variability over the study period was monotonic increases or decreases in abundance for 11 of 18 evaluated genera of marine birds; 8 genera had declined, whereas 3 had increased. The greatest declines occurred in genera associated with habitats that were deeper and farther from shore. Furthermore, most of the genera that declined primarily fed on pelagic prey resources, such as forage fish and mesozooplankton, and few were directly affected by the 1989 Exxon Valdez oil spill. Our observations of synchronous declines are indicative of a shift in pelagic components of PWS food webs. This pattern was correlated with climate variability at time-scales of several years to a decade.

Alaska↗
USGS2014

Polar bears from space: Assessing satellite imagery as a tool to track Arctic wildlife

Development of efficient techniques for monitoring wildlife is a priority in the Arctic, where the impacts of climate change are acute and remoteness and logistical constraints hinder access. We evaluated high resolution satellite imagery as a tool to track the distribution and abundance of polar bears. We examined satellite images of a small island in Foxe Basin, Canada, occupied by a high density of bears during the summer ice-free season. Bears were distinguished from other light-colored spots by comparing images collected on different dates. A sample of ground-truthed points demonstrated that we accurately classified bears. Independent observers reviewed images and a population estimate was obtained using mark- recapture models. This estimate (N: 94; 95% Confidence Interval: 92-105) was remarkably similar to an abundance estimate derived from a line transect aerial survey conducted a few days earlier (N: 102; 95% CI: 69-152). Our findings suggest that satellite imagery is a promising tool for monitoring polar bears on land, with implications for use with other Arctic wildlife. Large scale applications may require development of automated detection processes to expedite review and analysis. Future research should assess the utility of multi-spectral imagery and examine sites with different environmental characteristics.

PLoS ONE↗
USGS2022

Higher temperature sensitivity of flowering than leaf-out alters the time between phenophases across temperate tree species

Aim The aims of this study were to evaluate the changes in the length of the time period between leaf-out and flowering across temperate tree species, and associate these changes with potential physiological and environmental drivers to enhance mechanistic insight into these phenomena. Location Central Europe. Time period 1980–2016. Major taxa studied Six temperate woody species. Methods Statistical analyses were carried out based on long-term ground observations of both spring leaf-out and flowering across temperate tree species during 1980–2016, a period characterized by rapid warming. Results The temperature sensitivity of flowering (−5.4 ± 0.04 days/℃, mean ± SE ) was higher than that of leaf-out (−4.6 ± 0.04 days/℃) across all species, regardless of whether leaf-out occurred before or after flowering. This study postulates a hypothesis attributing the different temperature sensitivities to different thermal sensitivities, thermal requirements, and photoperiodic controls. Main conclusions The larger temperature sensitivity of flowering than leaf-out resulted in an extended time period between flowering and leaf-out in species that bloom before leafing out, but a shorter time period between these phenophases in species with the opposite strategy. We would like to emphasize the importance of changes in time period between different phenophases, and we recommend conducting experimental research to reveal the underlying mechanisms of plant phenology response to climate change, and to explore its potential ecological implications.

Global Ecology and Biogeography↗