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Since the first issue of the International Journal of Biometeorology in 1957, a total of 135 papers have reported on research in or of African countries. The majority of these have been on topics of animal biometeorology (36%), and the greatest proportion (24%) are situated in Nigeria. There has been a considerable increase in papers on African biometeorology since 2011, with those from this past decade accounting for 58% of all African papers in the journal. This occurs concurrent to an increase in the total number of papers published in the journal, driven by a move to the Editorial Manager system. While 66% of the papers on African biometeorology in the journal are authored by at least one person with an affiliation in the African continent, only 15 African countries are represented in the total authorship. As much of the African continent is projected to experience climatic changes exceeding the global mean, as much of the region is involved in animal and plant farming, and as seasonally-fluctuating and climatically affected diseases are common place, this low representation of work in Africa is surprising. This points to the need for greater awareness among African researchers of the discipline of biometeorology, greater involvement of African biometeorologists in International Society of Biometeorology and Commission meetings, and the inclusion of a greater number of African academics in the review process. This would be beneficial to the Society in increasing diversity and encouraging a more cosmopolitan engagement, and to the recognition of scientific development in African countries. [ABSTRACT FROM AUTHOR]

The number and diversity of phenological studies has increased rapidly in recent years. Innovative experiments, field studies, citizen science projects, and analyses of newly available historical data are contributing insights that advance our understanding of ecological and evolutionary responses to the environment, particularly climate change. However, many phenological data sets have peculiarities that are not immediately obvious and can lead to mistakes in analyses and interpretation of results. This paper aims to help researchers, especially those new to the field of phenology, understand challenges and practices that are crucial for effective studies. For example, researchers may fail to account for sampling biases in phenological data, struggle to choose or design a volunteer data collection strategy that adequately fits their project's needs, or combine data sets in inappropriate ways. We describe ten best practices for designing studies of plant and animal phenology, evaluating data quality, and analyzing data. Practices include accounting for common biases in data, using effective citizen or community science methods, and employing appropriate data when investigating phenological mismatches. We present these best practices to help researchers entering the field take full advantage of the wealth of available data and approaches to advance our understanding of phenology and its implications for ecology. [ABSTRACT FROM AUTHOR]

Climate change is affecting many living organisms; however, the responses of many of them remain unknown. In this paper, we present the results regarding the response of a bird species from the rallid family to the increased temperatures during the breeding season. We analysed the breeding data of Eurasian Coots nesting during 30 seasons between 1972 and 2019. During the study period, mean temperatures in April, the month when Coots start nesting, increased by 3.5 °C, and in months corresponding with the species breeding season by 2.6 °C. Breeding Coots advanced their earliest and median laying dates across the study period; however, the duration of their breeding season remained unchanged. We did not detect any significant temporal changes in clutch size, but clutches have become much more variable in size throughout the study period. Nest failures and production of offspring per nest did not change over the study period; however, the production of young per successful nest significantly declined. It is likely that this decline is the effect of mismatch between the period of food abundance (dipterans collected from water), and hatchling emergence, which is advanced due to change in climate. Future studies investigating the occurrence of dipteran resources at water bodies are needed to test this hypothesis. [ABSTRACT FROM AUTHOR]

This paper analyzes a long-term (1991–2019) flowering period of birch in the Czech Republic. Temporal and spatial evaluation in timing of beginning and end of flowering (Fbegin and Fend) and flowering period (Fperiod) of Betula pendula were investigated in different zones of the Czech Republic. The field observations were carried out at 44 sites of the Czech Hydrometeorological Institute phenological network; the detailed analysis including growing degree days (GDD) evaluation to Fbegin and Fend onsets and time of flowering were made at 9 sites in different altitudes. The trends and Pearson's correlation coefficients between Fbegin (Fend) and GDDs were calculated as well. The timing of both phenological stages showed a significant advance to earlier onsets (e.g., − 7.0 d per decade at Měděnec station) and the time of flowering shortens (e.g., − 3.8 d per decade at Rokytnice station). Nevertheless, the most marked shift was observed for mountain area in the north-western and north-eastern part of the Czech Republic. In contrast, the smallest shift was found in the southern part of the Czech Republic. The shift of the GDD values fluctuates from negative to positive values. Pearson's correlation coefficients calculated for both phenophases and period of flowering of Betula pendula showed the highest values in Fperiod (e.g., 0.846 at Modrava station) and in Fend (e.g., 0.711 at Rokytnice station) as well. Thus, our results indicate due to global warming symptoms that birch pollen allergy may appear earlier in the year but for a shorter period. [ABSTRACT FROM AUTHOR]

Phenological data have become increasingly important as indicators of long-term climate change. Consequently, long-term homogeneity of the records is an important aspect. In this paper, we apply a breakpoint detection algorithm to the phenological series from the Swiss Phenology Network (SPN). A combination of three statistical tests is applied and different constraints are tested with respect to the choice of reference series. Breakpoint detection is only possible for a fraction of the series due to the shortness of some series and the lack of suitable reference series. Spring phases are more likely to be suitable than fall phases because of their higher spatial correlation. Out of nearly 3000 phenological series with at least 20 data points, only about 5% were found to be significantly inhomogeneous, although a visual validation indicates that many mid-sized breakpoints remained undetected. The detected breakpoints were compared with metadata and more than half of them could be attributed to a change of observer. [ABSTRACT FROM AUTHOR]

The analysis of changes in the timing of life cycle-events of organisms (phenology) has been able to contribute significantly to the assessment of potential impacts of climate change on ecology. These phenological responses of species to changes in climate are likely to have significant relevance for socio-economic issues such as agriculture, forestry and human health and have proven able to play a role in raising environmental awareness and education on climate change. This paper presents the European Phenology Network (EPN), which aims to increase the efficiency, added value and use of phenological monitoring and research, and to promote the practical use of phenological data in assessing the impact of global (climate) change and possible adaptation measures. The paper demonstrates that many disciplines have to deal with changes in the timing of life-cycle events in response to climate change and that many different user groups are involved. Furthermore, it shows how EPN addresses issues such as (1) raising public awareness and education, (2) the integration and co-operation of existing observing systems, (3) integration and access to phenological information and (4) communication. [ABSTRACT FROM AUTHOR]

In recent decades, phenology has become an important tool by which to measure both the impact of climate change on ecosystems and the feedback of ecosystems to the climate system. However, there has been little attempt to date to systematically quantify the increase in the number of scientific publications with a focus on phenology and climate change. In order to partially address this issue, we examined the number of articles (original papers, reviews and short communications) containing the terms 'phenology' and 'climate change' in the title, abstract or keywords, published in the International Journal of Biometeorology in the 60 years since its inception in 1957. We manually inspected all issues prior to 1987 for the search terms and subsequently used the search facility on the Web of Science online database. The overall number of articles published per decade remained relatively constant (255-378) but rose rapidly to 1053 in the most recent decade (2007-2016), accompanied by an increase (41-172) in the number of articles containing the search terms. A number of factors may have contributed to this rise, including the recognition of the value of phenology as an indicator of climate change and the initiation in 2010 of a series of conferences focusing on phenology which subsequently led to two special issues of the journal. The word 'phenology' was in use from the first issue, whereas 'climate change' only emerged in 1987 and peaked in 2014. New technologies such as satellite remote sensing and the internet led to an expansion of and greater access to a growing reservoir of phenological information. The application of phenological data included determining the impact of warming of phenophases, predicting wine quality and the pollen season, demonstrating the potential for mismatch to occur and both reconstructing and forecasting climate. Even though this analysis was limited to one journal, it is likely to be indicative of a similar trend across other scientific publications. [ABSTRACT FROM AUTHOR]

While the climate of Western Europe has been deeply affected by the abrupt climate change that took place in the late '1980s of the twentieth century, a similar signal is detected only few years later, in 1994, in Georgia. Grapevine phenology is deeply influenced by climate and this paper aimed to analyze how phenological timing changed before and after the climatic change of 1994. Availability of thermal resources in the two climatic phases for the five altitudinal belts in the 0-1250-m range was analyzed. A phenological dataset gathered in two experimental sites during the period 2012-2014, and a suitable thermal dataset was used to calibrate a phenological model based on the normal approach and able to describe BBCH phenological stages 61 (beginning of flowering), 71 (fruit set), and 81 (veraison). Calibration was performed for four relevant Georgian varieties (Mtsvane Kakhuri, Rkatsiteli, Ojaleshi, and Saperavi). The model validation was performed on an independent 3-year dataset gathered in Gorizia (Italy). Furthermore, in the case of variety Rkatsiteli, the model was applied to the 1974-2013 thermal time series in order to obtain phenological maps of the Georgian territory. Results show that after the climate change of 1994, Rkatsiteli showed an advance, more relevant at higher altitudes where the whole increase of thermal resource was effectively translated in phenological advance. For instance the average advance of veraison was 5.9 days for 250-500 m asl belt and 18.1 days for 750-1000 m asl). On the other hand, at lower altitudes, phenological advance was depleted by superoptimal temperatures. As a final result, some suggestions for the adaptation of viticultural practices to the current climatic phase are provided. [ABSTRACT FROM AUTHOR]

Plant phenology networks of citizen scientists have a long history and have recently contributed to our understanding of climate change effects on ecosystems. This paper describes the development of the Alberta and Canada PlantWatch programs, which coordinate networks of citizen scientists who track spring development timing for common plants. Tracking spring phenology is highly suited to volunteers and, with effective volunteer management, observers will stay loyal to a phenology program for many years. Over two decades beginning in 1987, Alberta PlantWatch volunteers reported 47,000 records, the majority contributed by observers who participated for more than 9 years. We present a quantitative analysis of factors that determine the quality of this phenological data and explore sources of variation. Our goal is to help those who wish to initiate new observer networks with an analysis of the effectiveness of program protocols including selected plant species and bloom stages. [ABSTRACT FROM AUTHOR]

This paper examines the mean flowering times of 11 plant species in the British Isles over a 58-year period, and the flowering times of a further 13 (and leafing time of an additional 1) for a reduced period of 20 years. Timings were compared to Central England temperatures and all 25 phenological events were significantly related ( P<0.001 in all but 1 case) to temperature. These findings are discussed in relation to other published work. The conclusions drawn from this work are that timings of spring and summer species will get progressively earlier as the climate warms, but that the lower limit for a flowering date is probably best determined by examining species phenology at the southern limit of their distribution. [ABSTRACT FROM AUTHOR]

The Pan European Phenology (PEP) project is a European infrastructure to promote and facilitate phenological research, education, and environmental monitoring. The main objective is to maintain and develop a Pan European Phenological database (PEP725) with an open, unrestricted data access for science and education. PEP725 is the successor of the database developed through the COST action 725 “Establishing a European phenological data platform for climatological applications” working as a single access point for European-wide plant phenological data. So far, 32 European meteorological services and project partners from across Europe have joined and supplied data collected by volunteers from 1868 to the present for the PEP725 database. Most of the partners actively provide data on a regular basis. The database presently holds almost 12 million records, about 46 growing stages and 265 plant species (including cultivars), and can be accessed via http://www.pep725.eu/. Users of the PEP725 database have studied a diversity of topics ranging from climate change impact, plant physiological question, phenological modeling, and remote sensing of vegetation to ecosystem productivity. [ABSTRACT FROM AUTHOR]

Climate change has significantly impacted vegetation phenology across the globe with vegetation experiencing an advance in the spring green-up phases and a delay in fall senescence. However, some studies from high latitudes and high elevations have instead shown delayed spring phenology, owing to a lack of chilling fulfillment and altered snow cover and photoperiods. Here we use the MODIS satellite-derived view-angle corrected surface reflectance data (MCD43A4) to document the four phenological phases in the high elevations of the Sikkim Himalaya and compared the phenological trends between below-treeline zones and above-treeline zones. This analysis of remotely sensed data for the study period (2001-2017) reveals considerable shifts in the phenology of the Sikkim Himalaya. Advances in the spring start of the season phase (SOS) were more pronounced than delays in the dates for maturity (MAT), senescence (EOS), and advanced dormancy (DOR). The SOS significantly advanced by 21.3 days while the MAT and EOS were delayed by 15.7 days and 6.5 days respectively over the 17-year study period. The DOR showed an advance of 8.2 days over the study period. The region below the treeline showed more pronounced shifts in phenology with respect to an advanced SOS and a delayed EOS and DOR that above treeline. The MAT, however, showed a greater delay in the zone above the treeline than below. Lastly, unlike other studies from high elevations, there is no indication that winter chilling requirements are driving the spring phenology in this region. We discuss four possible explanations for why vegetation phenology in the high elevations of the Eastern Himalaya may exhibit trends independent of chilling requirements and soil moisture due to mediation by snow cover. [ABSTRACT FROM AUTHOR]

During the mid-summer month of January each year, the migrating brown-veined white butterflies (Belenois aurota, Fabricius, 1973) move through Johannesburg, South Africa, on their path from the Karoo to Mozambique. The result is a short period of approximately 3 days during which the skies of Johannesburg are filled with white butterflies, a spectacle that has been recorded in print media over the past century, and social media over the past decade. In this study, we mine these traditional and social media archives to produce the first multi-decadal phenological record of butterfly migration timing for South Africa, and explore the changes in timing and the role of climate thereof. We find a statistically significant advance in timing at a rate of 2.9 days per decade (r = 0.34, p = 0.0490). The climatic drivers of shifts in migratory species arrival are difficult to detect, as they involve the role of weather at the point of departure in determining the start of flight, and the weather en route to determine the path followed. However, statistically significant relationships are found between the arrival dates and both Tmin and precipitation in the month of December, and the combination thereof (r = 0.44, p = 0.0437 and r = 0.45, p = 0.0420 respectively). The findings of this study contribute to a growing literature documenting phenological shifts in South Africa, a previously under-represented region. [ABSTRACT FROM AUTHOR]

Phenology has emerged as a key metric to measure how species respond to changes in climate. Innovative means have been developed to extend the temporal and spatial range of phenological data by obtaining data from herbarium specimens, citizen science programs, and biodiversity data repositories. These different data types have seldom been compared for their effectiveness in detecting environmental impacts on phenology. To address this, we compare three separate phenology datasets from Denmark: (i) herbarium specimen data spanning 145 years, (ii) data collected from a citizen science phenology program over a single year observing first flowering, and (iii) data derived from incidental biodiversity observations in iNaturalist over a single year. Each dataset includes flowering day of year observed for three common spring-flowering plant species: Allium ursinum (ramsons), Aesculus hippocastanum (horse chestnut), and Sambucus nigra (black elderberry). The incidental iNaturalist dataset provided the most extensive geographic coverage across Denmark and the largest sample size and recorded peak flowering in a way comparable to herbarium specimens. The directed citizen science dataset recorded much earlier flowering dates because the program objective was to report the first flowering, and so was less compared to the other two datasets. Herbarium data demonstrated the strongest effect of spring temperature on flowering in Denmark, possibly because it was the only dataset measuring temporal variation in phenology, while the other datasets measured spatial variation. Herbarium data predicted the mean flowering day of year recorded in our iNaturalist dataset for all three species. Combining herbarium data with iNaturalist data provides an even more effective method for detecting climatic effects on phenology. Phenology observations from directed and incidental citizen science initiatives will increase in value for climate change research in the coming years with the addition of data capturing the inter-annual variation in phenology. [ABSTRACT FROM AUTHOR]

Apple phenology is greatly influenced by temperature. For quality apple production in the orchards, knowledge of the real timing of phenological stages is essential for scientific management decisions. In the Kashmir region, the year 2017 had a normal weather phenomenon, whereas the year 2018 had an erratic weather phenomenon wherein unusually high temperatures prevailed in the winter months and may be a clear sign of climate change effect. Due to this higher temperature in winter months of the year 2018 before bud break, earliness of phenological stages happened as compared to the year 2017, viz. silver tip stage by 5.67 days, green tip stage by 6.61 days, pink bud stage by 10.09 days, initial bloom by 10.43 days, full bloom by 9.70 days, and petal fall by 8.00 days. The flowering duration was overall recorded 2.43 days more in 2018 as compared to that in 2017. Due to the earliness of phenological stages in 2018, all twenty-five cultivars of the apple remained at high risk of spring frost and scientific apple orchard interventions were badly hit as growers were surprised and unprepared. The information generated will be very useful for growers, students, researchers, policy makers, and all the concerned stakeholders to understand how apple phenology responds to normal and extreme erratic weather conditions and may happen more frequently in the future due to climate change. [ABSTRACT FROM AUTHOR]

The annual Namaqualand daisy flowering spectacle is a world-renowned environmental event. Using documentary sources, including newspaper archives from The Rand Daily Mail, Volksblad and Die Burger and social media records from Flickr and iNaturalist, the first long-term phenological dataset spanning 1935–2018 was compiled for the Namaqualand region. The dataset contains first flowering, full bloom and end of bloom dates for the Namaqualand daisies. This study explores shifts in the timing of Namaqualand daisy bloom, and the role of climate in driving these phenological shifts. First flowering and full bloom phenology of the Namaqualand daisies are advancing at statistically significant rates of 2.6 days decade−1 and 2.1 days decade−1 respectively. Climatic data from seven Namaqualand weather stations, collectively spanning 1959–2018, were interrogated. For the periods spanned by both climate and phenology data, the relationships between the two were explored. Increasing temperatures are driving the calculated advances of the daisy flowering dates at statistically significant rates of change ranging from 0.01 to 0.11 days °C−1. The main climate drivers of Namaqualand daisy flowering phenology are winter and spring temperatures, the onset of the winter rainy season during April and May, and total winter precipitation. The rates of advance and climate drivers are broadly consistent with global phenological meta-analyses and records for the Southern Hemisphere. The advances in the timing of Namaqualand daisy flowering will have a significant impact on the tourism sector in the region, as flower viewing tours need to be prearranged months in advance. [ABSTRACT FROM AUTHOR]

The phenology of vegetation, namely leaf-out and senescence, can influence the Earth's climate over regional spatial scales and long time periods (e.g., over 30 years or more), in addition to microclimates over local spatial scales and shorter time periods (weeks to months). However, the effects of flowers on climate and microclimate are unknown. We investigate whether flowers can influence light reflected by the land surface and soil microclimate in a subalpine meadow. We conducted a flower removal experiment with a common sunflower species, Helianthella quinquenervis, for 3 years (2015, 2017, and 2019). The flower removal treatment simulates the appearance of the meadow when Helianthella flowers earlier under climate change and loses its flowers to frost (other plant structures are not damaged by frost). We test the hypotheses that a reduction in cover of yellow flowers leads to a greener land surface, lower reflectance, warmer and drier soils, and increased plant water stress. Flower removal plots are greener, reflect less light, exhibit up to 1.2 °C warmer soil temperatures during the warmest daylight hours, and contain ca. 1% less soil moisture compared to controls. However, soils were warmer in only 2 of the 3 years, when flower abundance was high. Helianthella water use efficiency did not differ between removal and control plots. Our study provides evidence for a previously undocumented effect of flowers on soil microclimate, an effect that is likely mediated by climate change and flowering phenology. Many anthropogenic environmental changes alter landscape albedo, all of which could be mediated by flowers: climate change, plant invasions, and agriculture. This study highlights how further consideration of the effects of flowers on land surface albedo could improve our understanding of the effects of vegetation on microclimate. [ABSTRACT FROM AUTHOR]

Drought-adapted geophytes are responding to the effects of climate change in arid and semi-arid environments. In this study, herbarium and historical rainfall data were used to examine the impact of rainfall changes on flowering trends of Pancratium tenuifolium Hochst. ex A.Rich and Scadoxus multiflorus (Martyn) Raf. subsp. multiflorus. Flowering was delayed by approximately 7 days per decade for P. tenuifolium during the period 1930 to 2018 and by approximately 14 days per decade for S. multiflorus subsp. multiflorus during the period 1924 to 2008. Scadoxus multiflorus subsp. multiflorus delayed the day of flowering by approximately 0.3 days per millimetre increase of rainfall, with Pancratium tenuifolium showing a non-significant response to summer rainfall during the same period. Overall, a linear mixed-effects model revealed that the day of flowering was delayed by approximately 8 days per degree rise in latitude and advanced by approximately 9 days per degree rise in longitude. Additionally, summer rainfall had significant effects on the day of flowering with a 1-mm increase in summer rainfall delaying the day of flowering by approximately 0.16 days. These changes in flowering times may ultimately alter the distribution of geophytes in Namibia. [ABSTRACT FROM AUTHOR]

This study examined relationships between temperature, precipitation, geo-topography, and the spring phenology of Fuji and Hongro apple cultivars along spatial gradients across South Korea. Phenology data was gathered from 2011 to 2014 in 42 uniformly managed research orchards which span a range in climate, latitude, and elevation. We used linear models and spatially explicit forecasts to study apple phenology under climate change scenarios. Given dry winters and complex terrain in South Korea, we hypothesized that, in addition to temperature, precipitation and geo-topographic factors influence apple phenology. We also expected responses to climate variation to be similar between (spatial) and within (temporal) orchards, given the controlled conditions and the use of apple clones in this study. With other factors held constant, phenological sensitivity ranged from − 3.2 to − 3.4 days °C−1 for air temperature and − 0.5 to − 0.6 days cm−1 for March precipitation in a combined model. When modeled without temperature, phenology changed by up to 10 days over the full range in March precipitation. Spring temperatures and precipitation in March had very little cross-correlation (r < 0.05), suggesting these patterns are independent; however, in a combined model including temperature, predicted changes in precipitation over the next 80 years have only a small impact on future apple phenology. Combining the best models with climate forecasts for South Korea, spring phenology continues to occur earlier over the next 80 years, mostly due to warming temperatures but with strong variation between regions. This suggests regionally specific climate change adaptation strategies are needed for future apple production in South Korea. [ABSTRACT FROM AUTHOR]

Studies have demonstrated that plant phenophases (e.g. budburst, flowering, ripening) are occurring increasingly earlier in the season across diverse ecologies globally. Despite much interest that climate change impacts have on coffee (Coffea arabica), relatively little is known about the driving factors determining its phenophases. Using high-resolution microclimatic data, this study provides initial insights on how climate change is impacting C. arabica phenophases in Tanzania. In particular, we use generalized additive models to show how warming nocturnal temperatures (Tnight), as opposed to day-time or maximum temperatures, have a superseding effect on the ripening of coffee and subsequent timing of harvest. A warm night index (WNI), generated from mean nocturnal temperature, permits accurate prediction of the start of the harvest season, which is superior to existing methods using growing degree days (GDD). The non-linear function indicates that a WNI of 15 °C is associated with the latest ripening coffee cherries (adjusted R2 = 0.95). As the WNI increases past the inflection point of ~ 16 °C, ripening occurs earlier and progresses more or less linearly at a rate of ~ 17 ± 1.95 days for every 1 °C increase in WNI. Using the WNI will thus not only allow farmers to more accurately predict their harvest start date, but also assist with identifying the most suitable adaptation strategies which may reduce harvest-related costs and buffer potential losses in quality and production. [ABSTRACT FROM AUTHOR]

As a result of climate change, causing high temperature, erratic precipitation, and extreme meteorological events, in recent times in Italy productivity of Maize is becoming less reliable. Climate change effects are accompanied by the increase in the presence of mycotoxins and various pathogens, which contribute to the reduction of the possibility of successfully producing Maize. In this framework, Proso Millet (Panicum miliaceum L.) may be an interesting alternative, as it is a relatively low-demanding crop, highly drought-resistant, and can be employed, similarly to Sorghum, in rotation, maintaining a certain amount of biodiversity and contributing to the revenue for the farmers. Moreover, Proso Millet has a very short cycle, and may be used as a catch crop, when other crops have failed or after their harvest. Millet used to be cultivated in ancient times in Italy, but then it was abandoned in favor of Maize, so now it is necessary to re-define proper agricultural practices and managements, as well as to remedy to the lack of an exact description of its phenological development. In the frame of a Life-CCA EU project, called Growing REsilience AgriculTure—Life (GREAT LIFE), aim of this work is to encode phenology of Proso Millet using BBCH scale. The lack of an exact definition of Proso Millet phenology is a major drawback in progressing in research on this crop, which could be a very valuable tool for improving the resilience of agro-ecosystems to climate change in the Mediterranean basin. For this purpose, Proso Millet was cultivated in two experimental sites in the Emilia-Romagna region (North of Italy). The crop was closely monitored throughout the life cycle, in order to document, even photographically, the achievement of the subsequent phenological phases (including the time necessary to reach each phenological stage, expressed as Days After Sowing—DAS). Thanks to weather data collection from agrometeorological stations close to the experimental fields, it was possible to correlate the phenological development to temperature-driven heat-unit accumulation (Cumulated Growing Degree Days—CGDD), using the single triangle method (useful tool for forecasting purposes). Ancillary agronomic data have also been collected, for completeness. This study well describes primary and secondary phenological stages of Proso Millet, managing at encoding them in the BBCH scale and contextually providing DAS and CGDD values necessary to achieve the different phenophases. The difference observed between the two experimental sites in reaching each BBCH stage according to both CGDD and DAS is mostly restrained, suggesting that this work may represent a valid first tool in defining the phenological development of Proso Millet in the areas of Northern Italy. The effort made to encode Proso Millet phenology in BBCH scale may be useful to give to researchers comprehensive indications for future agronomic surveys on the crop. The agronomic data collected show that the crop had a good agronomic performance despite the adverse weather pattern during the season, enlightening for farmers the opportunity offered by Millet in Italy as a resilient crop. [ABSTRACT FROM AUTHOR]

Anthropogenic warming's effects on phenology across environmental and temporal gradients are well recognized. Long-term phenological monitoring data are often limited in duration and geographic scope, but recent efforts to digitize herbaria collections make it possible to reliably reconstruct historic flowering phenology across broad geographic scales and multiple species, lending to an increased understanding of community response to climate change. In this study, we examined collection dates (1901 to 2015) of 8540 flowering specimens from 39 native species in the Pacific Northwest (PNW) region of North America. We hypothesized that flowering phenology would be sensitive to temperature but that sensitivity would vary depending on blooming season and geographic range position. As expected, we found that early-season bloomers are more sensitive to temperature than later-season bloomers. Sensitivity to temperature was significantly greater at low elevations and in the maritime (western) portion of the PNW than at higher elevations and in the eastern interior, respectively. The elevational and longitudinal effects on flowering sensitivity reflect spring "arriving" earlier at low elevations and in the maritime portion of the PNW. These results demonstrate that phenological responses to warming vary substantially across climatically diverse regions, warranting careful and nuanced consideration of climate warming's effects on plant phenology. [ABSTRACT FROM AUTHOR]

Climatic factors are of a big importance for the determination of phenological stages of several fruit tree species, including apple, during the pre- and post-blooming periods causing their modifications and consequently affecting the fruit quality and productivity. This study aimed to identify the important dormancy phases (chilling and forcing periods) involved in determination of the flowering time in Gala apple trees in order to estimate temperature and chill/heat requirements, useful to assess the effect of climatic factors and phenological modifications on apple productivity and quality. Phenological and climatic data (temperatures, rainfall, irrigation, chilling and heat requirements) were collected, calculated, and measured from orchard in Imouzzer-Kandar, Morocco. Fruit productivity and quality parameters (total yield, fruit weight, size, firmness, and sweetness) were measured. Results showed a prolonged chilling period basing on the pre-blooming phases identified using partial least squares regression. Inadequate chill during warm seasons (insufficient chilling requirements) induces some phenological perturbations: late flowering, extended flowering duration, and period from flowering to harvesting. These phenological anomalies affect negatively the fruit quality of apple as a cause of inadequate climatic factors, mainly temperature and chilling requirements during the chilling period. Our findings demonstrated that sufficient chilling and heat requirements correlate positively with fruit weight, size, and firmness, although the low irrigation applied during the period from flowering to the harvesting times. In unfavorable conditions, total yield and fruit sweetness could be improved by supplementary irrigation during the same period. Practically, chilling requirements of 645–677 chill hours, 709–1157 chill units, and 43.4–55.2 chill portions according to 0–7 °C, Utah model, and Dynamic model respectively and heat requirements of 26,290–27,057 growing degree hours are sufficient for good fruit quality. These are equivalent to temperature of 9.3–9.9 °C during the chilling period and 11.1–12.5 °C during the forcing period. These findings are useful for eventual management measures in order to improve apple production in their cropping area. At long terms, we propose necessity of rearrangement of high-chill apple varieties by low-chill cultivars as a way of apple crop adaptation to climate variations. [ABSTRACT FROM AUTHOR]

In the south of France, the so-called climate hiatus from 1998 to 2013 was associated with a late winter cooling which has affected the phenology of several reptiles and amphibian species, delaying their dates of first appearances in spring. This episode has been related to a period of frequently negative values of the North Atlantic Oscillation index (NAOi). The recent increase of this index after this episode marks the end of the "hiatus" and provides an opportunity to verify the impact of the North Atlantic Oscillation (NAO) on the fauna of the North Mediterranean region. Most of the emergence dates of amphibians and reptiles in spring have rapidly advanced from 1983 to 1997 and then receded or stabilized from 1998 to 2010. They began to advance again since 2010. These phenological changes covary with the temperature of February–March in the study area, which is itself related to the variations of the NAO index. These changes confirm the influence of the NAO on the phenology of terrestrial organisms in northern Mediterranean where its influence is sometimes assumed to be attenuated. [ABSTRACT FROM AUTHOR]

Evaluation of chilling requirements of cultivars of temperate fruit trees provides key information to assess regional suitability, according to winter chill, for both industry expansion and ongoing profitability as climate change progresses. Traditional methods for calculating chilling requirements use climate-controlled chambers and define chilling requirements (CR) using a fixed bud burst percentage, usually close to 50% (CR-50%). However, this CR-50% definition may estimate chilling requirements that lead to flowering percentages that are lower than required for orchards to be commercially viable. We used sweet cherry to analyse the traditional method for calculating chilling requirements (CR-50%) and compared the results with a more restrictive method, where the chilling requirement was defined by a 90% bud break level (CRm-90%). For sweet cherry, this higher requirement of flowering success (90% as opposed to 50%) better represents grower production needs as a greater number of flowers leads to greater potential yield. To investigate the future risk of insufficient chill based on alternate calculations of the chilling requirement, climate projections of winter chill suitability across Europe were calculated using CR-50% and CRm-90%. Regional suitability across the landscape was highly dependent on the method used to define chilling requirements, and differences were found for both cold and mild winter areas. Our results suggest that bud break percentage levels used in the assessment of chilling requirements for sweet cherry influence production risks of current and future production areas. The use of traditional methods to determine chilling requirements can result in an underestimation of productivity chilling requirements for tree crops like sweet cherry which rely on a high conversion of flowers to mature fruit to obtain profitable yields. This underestimation may have negative consequences for the fruit industry as climate change advances with climate risk underestimated. [ABSTRACT FROM AUTHOR]

Variation in ambient temperature affects various life stages of organisms. It has been suggested that climate change not only implies higher global temperatures but also more unpredictable weather and more frequent extreme weather events. Temperature has a major influence on the optimal laying-incubation-hatching dates of insectivorous passerines, because it poses energetic constraints and affects the timing of food abundance. We have been studying breeding characteristics of great tits Parus major and blue tits Cyanistes caeruleus in two areas, an urban parkland and a deciduous forest, around the city of Łódź since 2002. During the egg-laying period in 2017, both tit species at both study areas faced an unusual cold spell as reflected by a sudden decrease in the mean ambient temperature to ca. 2-3 °C for about 5 days, which caused mean hatching delays of up to 6 days. Since flexibility of behavior plays a major role in adjusting to unpredictable weather conditions, examining its limits may be an important goal for future research. [ABSTRACT FROM AUTHOR]

A national biodiversity and climate change adaptation plan is being developed for Ireland by the Department of Communications, Climate Action, and Environment. In order to inform such a plan, it was necessary to review and synthesize some of the recent literature pertaining to the impact of climate change on biodiversity in Ireland. Published research on this topic fell within three broad categories: (i) changes in the timing of life-cycle events (phenology) of plants, birds, and insects; (ii) changes in the geographic range of some bird species; and (iii) changes in the suitable climatic zones of key habitats and species. The synthesis revealed evidence of (i) a trend towards earlier spring activity of plants, birds, and insects which may result in a change in ecosystem function; (ii) an increase in the number of bird species; and (iii) both increases and decreases in the suitable climatic area of key habitats and species, all of which are expected to impact Ireland’s future biodiversity. This process identified data gaps and limitations in available information both of which could be used to inform a focused research strategy. In addition, it raises awareness of the potential implications of climate change for biodiversity in Ireland and elsewhere and demonstrates the need for biodiversity conservation plans to factor climate change into future designs. [ABSTRACT FROM AUTHOR]

Shifts in the timing of phenological events in plants and animals are cited as one of the most robust bioindicators of climate change. Much effort has thus been placed on the collection of phenological datasets, the quantification of the rates of phenological shifts and the association of these shifts with recorded meteorological data. These outputs are of value both in tracking the severity of climate change and in facilitating more robust management approaches in forestry and agriculture to changing climatic conditions. However, such an approach requires meteorological and phenological records spanning multiple decades. For communities in the Delta State of Nigeria, small-scale farming communities do not have access to meteorological records, and the dissemination of government issued daily to seasonal forecasts has only taken place in recent years. Their ability to survive inter-annual to inter-decadal climatic variability and longer-term climatic change has thus relied on well-entrenched indigenous knowledge systems (IKS). An analysis of the environmental cues that are used to infer the timing and amount of rainfall by farmers from three communities in the Delta State reveals a reliance on phenological events, including the croaking of frogs, the appearance of red millipedes and the emergence of fresh rubber tree and cassava leaves. These represent the first recorded awareness of phenology within the Delta State of Nigeria, and a potentially valuable source of phenological data. However, the reliance of these indicators is of concern given the rapid phenological shifts occurring in response to climate change. [ABSTRACT FROM AUTHOR]

In order to anticipate the ecological impacts of climate change and model changes to forests, it is important to understand the factors controlling spring leaf out. Leaf out phenology in woody trees and shrubs is generally considered to be strongly controlled by a combination of spring warming, winter chilling requirement, and photoperiod. However, researchers have recently suggested that temperature-related air humidity, rather than temperature itself, might be the main trigger of the spring leaf-out of woody plants. Here, we sought to examine the relationship between air humidity and leaf-out across a range of humidities and plant functional groups. We did not find any consistent, measurable effect of high humidity advancing leaf-out in the 15 woody shrubs and trees examined in this study, and we did not see progressive patterns of earlier leaf-out in successively higher humidities. Our results indicate that more work must be done on this topic before researchers can properly determine the effect of humidity on the leafing out process for woody species. [ABSTRACT FROM AUTHOR]

Climate warming and a shift in the timing of phenological phases, which lead to changes in the duration of the vegetation period may have an essential impact on the productivity of winter crops. The main purpose of this study is to examine climate change-related long-term (1961-2015) changes in the duration of both initial (pre-winter) and main (post-winter) winter wheat vegetation seasons and to present the projection of future phenological changes until the end of this century. Delay and shortening of pre-winter vegetation period, as well as the advancement and slight extension of the post-winter vegetation period, resulted in the reduction of whole winter wheat vegetation period by more than 1 week over the investigated 55 years. Projected changes in the timing of phenological phases which define limits of a main vegetation period differ essentially from the observed period. According to pessimistic (Representative Concentration Pathways 8.5) scenario, the advancement of winter wheat maturity phase by almost 30 days and the shortening of post-winter vegetation season by 15 days are foreseen for a far (2071-2100) projection. An increase in the available chilling amount is specific not only to the investigated historical period (1960-2015) but also to the projected period according to the climate change scenarios of climate warming for all three projection periods. Consequently, the projected climate warming does not pose a threat of plant vernalization shortage in the investigated geographical latitudes. [ABSTRACT FROM AUTHOR]

Historical temperature data and maturity records were analyzed for 45 vineyard blocks in 15 winegrowing regions across Australia in order to evaluate the suitability of common viticultural indices to estimate date of grape maturity. Five temperature-based viticultural indices (mean January temperature, mean growing season temperature, growing degree days, biologically effective degree days, Huglin Index) along with four springtime temperature indices (mean and maximum temperature summations for September, October, and November; growing degree days and biologically effective degree days modified to include September) were compared to maturity data in order to investigate index relationship to observed maturity timing. Daily heat summations for the months of September, October, and November showed the best correlation to day of year of maturity, suggesting that springtime temperatures are important relative to the timing of grape maturity. Mean January temperature, a commonly used index, had the poorest correlation with day of year of maturity of all the indices included in this study. Indices that included the month of April had poorer correlation than indices that shifted the months included in the growing season to be from September to March inclusive. Calculated index values for the past 30 years for every region included in this study showed increasing temporal trends to various degrees, indicating that all regions studied are experiencing warming temperatures during the growing season. These results emphasize the need to reevaluate viticultural indices in the context of a changing climate. [ABSTRACT FROM AUTHOR]

A correction is presented to the article "Grapevine phenology and climate change in Georgia" that was presented in the 8 December 2016 issue.

Aerobiology and biometeorology are related fields. Here we provide a broad review of aerobiology articles published in the International Journal of Biometeorology (IJB) over the past 60 years. We consider how the quantity of such work has varied over this period as well as which regions and countries have been the focus of such work, and where there is a relative paucity. We then focus on a number of highlights and themes in this research, including aerobiology and climate change and aerobiological modelling and forecasting. While much of the article focusses on airborne pollen research, we also discuss the extent to which other airborne organic particles such as fungal spores and bacteria have been the focus of research published in IJB. Also considered are knowledge gaps and research needs and priorities with respect to the field of aerobiology. While the IJB has been one of the main platforms for presenting aerobiological research over recent decades, the article highlights the need for the field of aerobiology to embrace new sampling technologies such as spectral analysis and next-generation sequencing to identify and quantify airborne biological particles. [ABSTRACT FROM AUTHOR]

Although the responses of living organisms to climate change are being widely investigated, little attention has been given to such effects late in the growing season. We studied the late-season flight times of 20 species of butterflies in a geographically limited region, the state of Massachusetts in the USA, by examining change in dates of flight over a 22-year period and in response to average monthly temperature and precipitation. By analyzing the last 10% of each year's observations reported by observers of the Massachusetts Butterfly Club, we found that seven species remain in flight significantly later into the fall than they did two decades earlier, while two species show reduced late-season flight. Life history characteristics of the species, particularly voltinism and average fall flight dates, influenced whether warmer fall months led to increases or decreases in fall flight. Warmer Novembers often led to later fall flight, and wetter Augusts usually extended fall flight. These results document the effects of climate on late-season flight times of butterflies, add to an understanding of how warmer autumn conditions alter the phenology of different butterfly species, and show the usefulness of citizen science data. [ABSTRACT FROM AUTHOR]

Long-term phenological data have been crucial at documenting the effects of climate change in organisms. However, in most animal taxa, time series length seldom exceeds 35 years. Therefore, we have limited evidence on animal responses to climate prior to the recent warm period. To fill in this gap, we present time series of mean first arrival dates to Central Europe for 13 bird species spanning 183 years (1828-2010). We found a uniform trend of arrival dates advancing in the most recent decades (since the late 1970s). Interestingly, birds were arriving earlier during the cooler early part of the nineteenth century than in the recent warm period. Temperature sensitivity was slightly stronger in the warmest 30-year period (−1.70 ± SD 0.47 day °C) than in the coldest period (−1.42 ± SD 0.89 day °C); however, the difference was not statistically significant. In the most recent decades, the temperature sensitivity of both short- and long-distance migrants significantly increased. Our results demonstrate how centennial time series can provide a much more comprehensive perspective on avian responses to climate change. [ABSTRACT FROM AUTHOR]

Long-term changes of plant phenological phases determined by complex interactions of environmental factors are in the focus of recent climate impact research. There is a lack of studies on the comparison of biogeographical regions in Europe in terms of plant responses to climate. We examined the flowering phenology of plant species to identify the spatio-temporal patterns in their responses to environmental variables over the period 1970-2010. Data were collected from 12 countries along a 3000-km-long, North-South transect from northern to eastern Central Europe. Biogeographical regions of Europe were covered from Finland to Macedonia. Robust statistical methods were used to determine the most influential factors driving the changes of the beginning of flowering dates. Significant species-specific advancements in plant flowering onsets within the Continental (3 to 8.3 days), Alpine (2 to 3.8 days) and by highest magnitude in the Boreal biogeographical regions (2.2 to 9.6 days per decades) were found, while less pronounced responses were detected in the Pannonian and Mediterranean regions. While most of the other studies only use mean temperature in the models, we show that also the distribution of minimum and maximum temperatures are reasonable to consider as explanatory variable. Not just local (e.g. temperature) but large scale (e.g. North Atlantic Oscillation) climate factors, as well as altitude and latitude play significant role in the timing of flowering across biogeographical regions of Europe. Our analysis gave evidences that species show a delay in the timing of flowering with an increase in latitude (between the geographical coordinates of 40.9 and 67.9), and an advance with changing climate. The woody species (black locust and small-leaved lime) showed stronger advancements in their timing of flowering than the herbaceous species (dandelion, lily of the valley). In later decades (1991-2010), more pronounced phenological change was detected than during the earlier years (1970-1990), which indicates the increased influence of human induced higher spring temperatures in the late twentieth century. [ABSTRACT FROM AUTHOR]

There is growing concern about declines in pollinator species, and more recently reservations have been expressed about mismatch in plant-pollinator synchrony as a consequence of phenological change caused by rising temperatures. Long-term changes in honeybee Apis mellifera phenology may have major consequences for agriculture, especially the pollinator market, as well as for honey production. To date, these aspects have received only modest attention. In the current study, we examine honeybee and beekeeping activity in southern Poland for the period 1965-2010, supplemented by hive yields from a beekeeper in southern UK in the same period. We show that despite negative reports on honeybee condition, and documented climate change, the studied apiary managed to show a marked increase in honey production over the 46 year study period, as did that from the UK. The proportion of the annual yield originating from the first harvest decreased during the study period and was associated with rising temperatures in summer. Honeybee spring phenology showed strong negative relationships with temperature but no overall change through time because temperatures of key early spring months had not increased significantly. In contrast, increasing yields and an increased number of harvests (and hence a later final harvest and longer season) were detected and were related to rising temperatures in late spring and in summer. [ABSTRACT FROM AUTHOR]

An observed increase in air temperature can lead to significant changes in the phenology of plants and, consequently, changes in agricultural production. The aim of the study was to evaluate the spatial differentiation of thermal resources in Poland and their variability during a period of changing thermal conditions in Europe. Since the variability of thermal conditions is of paramount importance for perennial crops, the study focused on apple, plum, and cherry orchard regions in Poland. The analysis was conducted for the period of 1951-2010 using air temperature daily data. Thermal resources have been defined using the growing degree days (GDD) index calculated independently for the whole year and during in frost-free season for three air temperature thresholds: 0, 5, and 10 °C, which determine the non-winter period, growing season, and the period of full plant growth, respectively. In addition, due to the high significance for perennials in particular, the incidence and intensity of frost during flowering were calculated. In this study, a detailed analysis of the spatial differentiation of thermal resources was first performed, followed by an evaluation of long-term variability and associated change patterns. The obtained results confirmed an increase in thermal resources in Poland as a consequence of the lengthening of the growing season. However, the frequency and intensity of spring frost, especially during flowering or even during ripening of plants, remain a threat to harvests in both the eastern and western parts of the country. [ABSTRACT FROM AUTHOR]

Many avian species in Europe breed earlier as a result of higher temperatures caused by global climate changes. Climate change means not only higher temperatures but also more frequent extreme weather events, sometimes contrasting with the long-term trends. It was suggested that we should look closely at every extreme phenomenon and its consequences for the phenology of organisms. Examining the limits of phenotypic plasticity may be an important goal for future research. Extremely low spring temperatures in 2013 (coldest spring in 40 years) resulted in birds laying unusually late, and it was followed in 2014 by the earliest breeding season on record (warmest spring in 40 years). Here, we present results concerning breeding phenology and double-broodedness in the Great Tit ( Parus major) and the Blue Tit ( Cyanistes caeruleus) in 2013 and 2014 in an urban parkland and a deciduous forest in central Poland. Great Tits started laying eggs 18.2 days later in 2013 than in 2014 in the parkland, whereas the analogous difference was 21.1 days in the forest. Blue Tits started laying eggs in the parkland 18.5 days later in 2013 than in 2014, while the analogous difference was 21.6 days in the forest. The difference in the proportion of second clutches in Great Tits between 2013 (fewer second clutches) and 2014 (more second clutches) was highly significant in the parkland and in the forest. This rather large extent of breeding plasticity has developed in reaction to challenges of irregular inter-annual variability of climatic conditions. Such a buffer of plasticity may be sufficient for Blue Tits and Great Tits to adjust the timing of breeding to the upcoming climate changes. [ABSTRACT FROM AUTHOR]

Over a large temperature range, the statistical association between spring phenology and temperature is often regarded and treated as a linear function. There are suggestions that a sigmoidal relationship with definite upper and lower limits to leaf unfolding and flowering onset dates might be more realistic. We utilised European plant phenological records provided by the European phenology database PEP725 and gridded monthly mean temperature data for 1951-2012 calculated from the ENSEMBLES data set E-OBS (version 7.0). We analysed 568,456 observations of ten spring flowering or leafing phenophases derived from 3657 stations in 22 European countries in order to detect possible nonlinear responses to temperature. Linear response rates averaged for all stations ranged between −7.7 (flowering of hazel) and −2.7 days °C (leaf unfolding of beech and oak). A lower sensitivity at the cooler end of the temperature range was detected for most phenophases. However, a similar lower sensitivity at the warmer end was not that evident. For only ∼14 % of the station time series (where a comparison between linear and nonlinear model was possible), nonlinear models described the relationship significantly better than linear models. Although in most cases simple linear models might be still sufficient to predict future changes, this linear relationship between phenology and temperature might not be appropriate when incorporating phenological data of very cold (and possibly very warm) environments. For these cases, extrapolations on the basis of linear models would introduce uncertainty in expected ecosystem changes. [ABSTRACT FROM AUTHOR]

Trends in the timing of spring and autumn phenophases of Betula pubescens were investigated in the southern, middle, and northern boreal zones in Finland. The field observations were carried out at 21 sites in the Finnish National Phenological Network in 1997-2013. The effective temperature sum of the thermal growth period, i.e. the sum of the positive differences between diurnal mean temperatures and 5 °C (ETS1), increased annually on average by 6-7 degree day units. Timing of bud burst remained constant in the southern and middle boreal zones but advanced annually by 0.5 day in the northern boreal zone. The effective temperature sum at bud burst (ETS2) showed no trend in the southern and middle boreal zones, whereas ETS2 increased on average from 20-30 to 50 degree day units in the northern boreal zone, almost to the same level as in the other zones. Increase in ETS2 indicates that the trees did not start their growth in very early spring despite warmer spring temperatures. The timing of leaf colouring and leaf fall remained almost constant in the southern boreal zones, whereas these advanced annually by 0.3 and 0.6 day in the middle boreal zone and by 0.6 and 0.4 day in the northern boreal zone, respectively. The duration of the growth period remained constant in all boreal zones. The results indicate high buffering capacity of B. pubescens against temperature changes. The study also shows the importance of the duration of phenological studies: some trends in spring phenophases had levelled out, while new trends in autumn phases had emerged after earlier studies in the same network for a shorter observation period. [ABSTRACT FROM AUTHOR]

Urbanization and its resultant urban heat island provide a means for evaluating the impact of climate warming on vegetation phenology. To predict the possible response of vegetation phenology to rise of temperature, it is necessary to investigate factors influencing vegetation phenology in different climate zones. The start of growing season (SOS) in seven cities located in the middle temperate humid, semi-humid, semi-arid, and arid climate zones in China was extracted based on satellite-derived normalized difference vegetation index (NDVI) data. The dynamics of urban SOS from 2000 to 2009 and the correlations between urban SOS and land surface temperatures (LST), precipitation, and sunshine duration, respectively, were analyzed. The results showed that there were no obvious change trends for urban SOS, and the heat island induced by urbanization can make SOS earlier in urban areas than that in adjacent rural areas. And the impact of altitude on SOS was also not negligible in regions with obvious altitude difference between urban and adjacent rural areas. Precipitation and temperature were two main natural factors influencing urban SOS in the middle temperate zone, but their impacts varied with climate zones. Only in Harbin city with lower sunshine duration in spring, sunshine duration had more significant impact than temperature and precipitation. Interference of human activities on urban vegetation was non-negligible, which can lower the dependence of urban SOS on natural climatic factors. [ABSTRACT FROM AUTHOR]

Following an age-old tradition, since 1740, in the town of Kőszeg in western Hungary, samples of grapevine shoots are annually harvested on St. George's Day, 24 April, and then are pictorially reproduced in the so-called Book of Vinesprouts. Given the strong relationships between temperature and grapevine phenology, the book represents a potential source for reconstructing past spring temperatures. However, this document has been little utilized so far, due to high varietal heterogeneity and lingering uncertainty regarding cultivar identity. This research developed an approach to address these difficulties, by means of a single-cultivar-based modeling analysis, associated with a set of alternative hypotheses about cultivar early development for the period to be reconstructed. Each hypothesis allowed the calculation of a different past temperature reconstruction, which was evaluated against contemporary independent observational data. The results showed that all the development stages recorded before 1900 were compatible with a vine type with a very low heat requirement for bud burst. Estimates were derived from a model calibrated on a subset of drawings of unknown cultivars executed between 1875 and 1898. The model based on this data subset was the only one giving a consistent reconstruction of spring temperatures, expressed as accumulated growing degree days going back to 1740. Although some uncertainty still exists regarding the reconstruction, the research shows that the Book of Vinesprouts contains generally consistent information about spring temperatures for a period of over 269 years for this region of Hungary. [ABSTRACT FROM AUTHOR]

Understanding how changing climate and cultivars influence crop phenology and potential yield is essential for crop adaptation to future climate change. In this study, crop and daily weather data collected from six sites across the North China Plain were used to drive a crop model to analyze the impacts of climate change and cultivar development on the phenology and production of winter wheat from 1981 to 2005. Results showed that both the growth period (GP) and the vegetative growth period (VGP) decreased during the study period, whereas changes in the reproductive growth period (RGP) either increased slightly or had no significant trend. Although new cultivars could prolong the winter wheat phenology (0.3∼3.8 days per decade for GP), climate warming impacts were more significant and mainly accounted for the changes. The harvest index and kernel number per stem weight have significantly increased. Model simulation indicated that the yield of winter wheat exhibited increases (5.0∼19.4 %) if new cultivars were applied. Climate change demonstrated a negative effect on winter wheat yield as suggested by the simulation driven by climate data only (−3.3 to −54.8 kg ha year, except for Lushi). Results of this study also indicated that winter wheat cultivar development can compensate for the negative effects of future climatic change. [ABSTRACT FROM AUTHOR]

In the USA, thousands of volunteers are engaged in tracking plant and animal phenology through a variety of citizen science programs for the purpose of amassing spatially and temporally comprehensive datasets useful to scientists and resource managers. The quality of these observations and their suitability for scientific analysis, however, remains largely unevaluated. We aimed to evaluate the accuracy of plant phenology observations collected by citizen scientist volunteers following protocols designed by the USA National Phenology Network (USA-NPN). Phenology observations made by volunteers receiving several hours of formal training were compared to those collected independently by a professional ecologist. Approximately 11,000 observations were recorded by 28 volunteers over the course of one field season. Volunteers consistently identified phenophases correctly (91 % overall) for the 19 species observed. Volunteers demonstrated greatest overall accuracy identifying unfolded leaves, ripe fruits, and open flowers. Transitional accuracy decreased for some species/phenophase combinations (70 % average), and accuracy varied significantly by phenophase and species ( p < 0.0001). Volunteers who submitted fewer observations over the period of study did not exhibit a higher error rate than those who submitted more total observations. Overall, these results suggest that volunteers with limited training can provide reliable observations when following explicit, standardized protocols. Future studies should investigate different observation models (i.e., group/individual, online/in-person training) over subsequent seasons with multiple expert comparisons to further substantiate the ability of these monitoring programs to supply accurate broadscale datasets capable of answering pressing ecological questions about global change. [ABSTRACT FROM AUTHOR]

Climate change significantly affects insects' behaviors. Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) is one of the most serious insect pests in the world. Much is known about the survival of the overwintering population and spring emergence of H. armigera. However, little is known about the effects of climate change on overwintering and spring emergence of H. armigera. This study investigated the effects of changes of air and soil temperatures and precipitation on overwintering pupae of H. armigera by analyzing historical data from Magaiti County in northwest China using statistical methods. The results showed that during the period of 1989-2006, the climate warming advanced the first-appearance date of overwintering pupae eclosion (FD) and end date of overwintering pupae eclosion (ED) by 1.276 and 0.193 days per year, respectively; the duration between the FD and ED (DFEPE) was prolonged by 1.09 days per year, which resulted in more eclosion of overwintering pupae. For a 1 °C increase in the maximum air temperature ( T) in winter, the FD became earlier by 3.234 days. Precipitation in winter delayed the FD and ED and produced little relative influence on DFEPE. A 1-mm increase of precipitation in winter delayed the FD and ED by 0.850 and 0.494 days, respectively. Mean air temperature ( T) in March, with a 41.3 % relative influence, precipitation in winter, with a 49.0 % relative influence, and T in March, with a 37.5 % relative influence, were the major affecting factors on FD, ED, and DFEPE, respectively. T in February with a 53.0 % relative influence was the major affecting factor on the mortality of overwintering pupae (MOP). Increased soil temperatures in October and November and autumn and air temperatures in winter could decrease the MOP, though the relative influences were lower than T in February. Increased precipitation in winter increased the MOP, but the relative influence was only 4.2 % because of little precipitation. T in October had the greatest influence on the pre-wintering density of pupae (PDP). Increasing soil temperatures in October, November, and autumn increased PDP. A higher PDP increased overwintering survival and advanced FD and prolonged DFEPE. The overwintering boundary air temperatures of H. armigera should be expanded due to higher soil temperature and snow covering. Thus, climate warming helped to enhance the survival of overwintering pupae. [ABSTRACT FROM AUTHOR]

Although many studies have indicated the consistent impact of warming on the natural ecosystem (e.g., an early flowering and prolonged growing period), our knowledge of the impacts on agricultural systems is still poorly understood. In this study, spatiotemporal variability of the heading-flowering stages of single rice was detected and compared at three different scales using field-based methods (FBMs) and satellite-based methods (SBMs). The heading-flowering stages from 2000 to 2009 with a spatial resolution of 1 km were extracted from the SPOT/VGT NDVI time series data using the Savizky-Golay filtering method in the areas in China dominated by single rice of Northeast China (NE), the middle-lower Yangtze River Valley (YZ), the Sichuan Basin (SC), and the Yunnan-Guizhou Plateau (YG). We found that approximately 52.6 and 76.3 % of the estimated heading-flowering stages by a SBM were within ±5 and ±10 days estimation error (a root mean square error (RMSE) of 8.76 days) when compared with those determined by a FBM. Both the FBM data and the SBM data had indicated a similar spatial pattern, with the earliest annual average heading-flowering stages in SC, followed by YG, NE, and YZ, which were inconsistent with the patterns reported in natural ecosystems. Moreover, diverse temporal trends were also detected in the four regions due to different climate conditions and agronomic factors such as cultivar shifts. Nevertheless, there were no significant differences ( p > 0.05) between the FBM and the SBM in both the regional average value of the phenological stages and the trends, implying the consistency and rationality of the SBM at three scales. [ABSTRACT FROM AUTHOR]

In recent years, a growing body of evidence has emerged indicating that the relationship between flowering phenology and climate may differ throughout various portions of the growing season. These differences have resulted in long-term changes in flowering synchrony that may alter the quantity and diversity of pollinator attention to many species, as well as altering food availability to pollenivorous and nectarivorous animal species. However, long-term multi-season records of past flowering timing have primarily focused on temperate environments. In contrast, changes in flowering phenology within humid subtropical environments such as the southeastern USA remain poorly documented. This research uses herbarium-based methods to examine changes in flowering time across 19,328 samples of spring-, summer-, and autumn-flowering plants in the southeastern USA from the years 1951 to 2009. In this study, species that flower near the onset of the growing season were found to advance under increasing mean March temperatures (−3.391 days/°C, p = 0.022). No long-term advances in early spring flowering or spring temperature were detected during this period, corroborating previous phenological assessments for the southeastern USA. However, late spring through mid-summer flowering exhibited delays in response to higher February temperatures (over 0.1.85 days/°C, p ≤ 0.041 in all cases). Thus, it appears that flowering synchrony may undergo significant restructuring in response to warming spring temperatures, even in humid subtropical environments. [ABSTRACT FROM AUTHOR]

The Tibetan Plateau, a unique cold and dry region recognized as the Earth's third pole, is primarily composed of alpine grasslands (>60 %). While a warming climate in the plateau is being recorded, phenology of alpine grasslands and its climatic dependencies are less investigated. This study tests the feasibility of the frequently observed Moderate Resolution Imaging Spectroradiometer (MODIS) time series (500 m, 8 days) in examining alpine phenology in the plateau. A set of phenological metrics are extracted from the MODIS Normalized Difference Vegetation Index (NDVI) series in each year, 2000-2010. A nonparametric Mann-Kendall trend analysis is performed to find the trends of these phenological metrics, which are then linked to monthly climatic records in the growing season. Opposite trends of phenological change are observed between the east and west of the plateau, with delayed start of season, peak date, and end of season in the west and advanced phenophases in the east. The correlation analysis indicates that precipitation, with a decreasing trend in the west and increasing trend in the east, may serve as the primary driver of the onset and peak dates of greenness. Temperature increases all over the plateau. While the delay of the end of season in the west could be related to higher late-season temperature, its advance in the east needs further investigation in this unique cold region. This study demonstrates that frequent satellite observations are able to extract phenological features of alpine grasslands and to provide spatiotemporally detailed base information for long-term monitoring on the plateau under rapid climate change. [ABSTRACT FROM AUTHOR]

With global warming, an advance in spring leaf phenology has been reported worldwide. However, it is difficult to forecast phenology for a given species, due to a lack of knowledge about chilling requirements. We quantified chilling and heat requirements for leaf unfolding in two European tree species and investigated their relative contributions to phenological variations between and within populations. We used an extensive database containing information about the leaf phenology of 14 oak and 10 beech populations monitored over elevation gradients since 2005. In parallel, we studied the various bud dormancy phases, in controlled conditions, by regularly sampling low- and high-elevation populations during fall and winter. Oak was 2.3 times more sensitive to temperature for leaf unfolding over the elevation gradient and had a lower chilling requirement for dormancy release than beech. We found that chilling is currently insufficient for the full release of dormancy, for both species, at the lowest elevations in the area studied. Genetic variation in leaf unfolding timing between and within oak populations was probably due to differences in heat requirement rather than differences in chilling requirement. Our results demonstrate the importance of chilling for leaf unfolding in forest trees and indicate that the advance in leaf unfolding phenology with increasing temperature will probably be less pronounced than forecasted. This highlights the urgent need to determine experimentally the interactions between chilling and heat requirements in forest tree species, to improve our understanding and modeling of changes in phenological timing under global warming. [ABSTRACT FROM AUTHOR]