Late Spring Summer Research Articles

Short-terms variability of water properties and phytoplankton blooms along the central eastern Florida shelf edge

The central eastern Florida shelf edge is a highly dynamic area that supports an important yet vulnerable deep-sea coral reefs ecosystem, the Oculina Coral Habitat Area of Particular Concern. Rapid and large short-terms (days to weeks) changes of bottom temperature (up to 9 °C) and pCO2 (up to 180 μatm) were observed at the shelfbreak during a two-month (May 13-July 10, 2017) deployment of a lander package. An analysis suggests that these changes are the combined results of tides, the Gulf Stream meandering, and submesoscale eddies and filaments. The processes responsible for sub-tidal variability may include 1) the Gulf Stream frontal movements, 2) upwelling/downwelling of slope waters in association with the Gulf Stream variability, and 3) submesoscale processes and associated vertical movements. Satellite images also frequently show a narrow plume of elevated chlorophyll concentration that stretches from the coast northward up to >200 km along the Gulf Stream front during late spring and early summer. Our analysis indicates that these phytoplankton blooms in the plume are likely supported by the nutrient supply from the nutrients-rich slope waters to the shelf edge and subsequent local vertical mixing. Carbon export associated with these blooms can be an important food source to the Oculina corals. Upwelling of slope waters, on the other hand, will lead to increased CO2 and reduced pH and aragonite saturation state along the shelf edge. Therefore, these dynamic processes may have strong impacts on the health and sustainability of the Oculina coral ecosystem.

Increasing Occurrence of Sudden Turns From Drought to Flood Over China

AbstractThis study focuses on a new compounding concern, the sudden turn from drought to flood (STDF), that is becoming increasingly prominent. This study investigates the long‐term trends and variability of STDFs in China during 1961–2020. The findings indicate that STDFs are prevalent in north and northeast China, and the Yangtze River Delta (YRD). The probability of a drought being followed by a severe flood is approaching 35% in northern and northeastern China. Since 1961, the number of STDFs in China has increased at a rate of average 2.8 events per decade. This increase mainly has occurred in late spring and early summer. The likelihood that a drought being followed by a significant pluvial is also increasing. The increasing STDF in northern China is mainly attributable to the increasing flood frequency and volatility of precipitation. Changes in the STDF trend is more dependent on the drought frequency in the YRD.

MFCC Selection by LASSO for Honey Bee Classification

The recent advances in smart beekeeping focus on remote solutions for bee colony monitoring and applying machine learning techniques for automatic decision making. One of the main applications is a swarming alarm, allowing beekeepers to prevent the bee colony from leaving their hive. Swarming is a naturally occurring phenomenon, mainly during late spring and early summer, but it is extremely hard to predict its exact time since it is highly dependent on many factors, including weather. Prevention from swarming is the most effective way to keep bee colonies; however, it requires constant monitoring by the beekeeper. Drone bees do not survive the winter and they occur in colonies seasonally with a peak in late spring, which is associated with the creation of drone congregation areas, where mating with young queens takes place. The paper presents a method of early swarming mood detection based on the observation of drone bee activity near the entrance to a hive. Audio recordings are represented by Mel Frequency Cepstral Coefficients and their first and second derivatives. The study investigates which MFCC coefficients, selected by the Least Absolute Shrinkage and Selection Operator, are significant for the worker bee and drone bee classification task. The classification results, obtained by an autoencoder neural network, allow to improve the detection performance, achieving accuracy slightly above 95% for the chosen set of signal features, selected by the proposed method, compared to the standard set of MFCC coefficients with only up to 90% accuracy.

Phytoplankton Dynamics and Biogeochemistry: Model Studies

The seasonal dynamics of the NE Black Sea phytoplankton follow the following pattern: small diatoms (spring) → coccolithophorid Emiliania huxleyi (late spring–early summer) → large diatoms (summer). Our hypothesis states that nitrogen and phosphorus concentrations regulate the seasonal phytoplankton dynamics. A minimum number of parameters is enough to understand the mechanisms of dominant species change. Based on the concept of intracellular regulation, the following parameters were evaluated: the minimum nitrogen and phosphorus quotas; half-saturation constants for nitrogen and phosphorus uptake; the maximum specific growth rate of the dominant phytoplankton species. Computational experiments on the model show the following: (1) in spring, a species with a high maximum specific growth rate becomes dominant; (2) in late spring and early summer, a species with a low minimum nitrogen quota and a low half-saturation constant for nitrogen uptake is observed; (3) in summer, a low minimum phosphorus quota and a low half-saturation constant for phosphorus uptake allow the species to become dominant.

Life cycle and seasonal regulation of Onychogomphus forcipatus unguiculatus in the Seybouse River, Algeria (Insecta: Odonata)

Understanding the seasonal regulation and life cycle patterns of Odonata is critical to identifying the factors that influence their voltinism. While the life history and seasonal regulation of Odonata, particularly gomphids, has been studied extensively, few studies have focused on North African gomphids. This study aims to contribute to the understanding of the life cycle of Onychogomphus forcipatus unguiculatus (Vander Linden, 1823), a western Mediterranean gomphid, on the Seybouse River in northeastern Algeria and discuss its seasonal regulation. Our results imply that a generation of O. f. unguiculatus requires two years to develop. The appearance of small (F-6) larvae in early spring can be attributed to the hatching of eggs in the previous year, followed by their overwintering in interstitial habitats. This abrupt appearance of small larvae is the result of their unique life history strategy of developing and surviving in specialized habitats during winter, then continuously growing and developing. The senior cohort overlaps with its junior counterpart, overwintering primarily in instars F-1, F-2, and, to a lesser extent, F-3, before beginning to emerge in late spring and early summer. By examining the voltinism and life cycle patterns of O. f. unguiculatus, this study contributes to our understanding of the reproductive strategies and population dynamics of this western Mediterranean gomphid, as well as of factors affecting the phenology and ecology of Odonata, particularly in North Africa, and in this manner contributes to overall efforts to protect and manage freshwater ecosystems in this region.

Retrospective Analysis of Suicide Deaths in Allen County Indiana, 2013 – 2022

Suicide rates at a national and state level have been on the rise over the past two decades. Patterns observed at the local level is less understood and underrepresented in research. Since local government can have a large impact on resource allocation in a community, revealing local suicide patterns could help facilitate targeted preventative efforts for at-risk populations. This study aims to analyze demographic patterns observed in Allen County suicides from 2013 –2022, focusing on age groups and education attainment. Data collection was completed on the 604 individuals who died by suicide in Allen County over the past decade. The collection process included documenting various demographics accessed through death certificates and coroner’s files. Within the county, suicide numbers increased over the decade. Results showed that males represented more than a 3:1 ratio of total suicides, a gunshot wound was the method of injury for 53% of all suicides, and decedents with a high school degree or less represented 62% of suicides within the population. These results echo what research has shown at the national level. Additionally, the 20-34 and the 35-54 age groups produced the greatest number of suicides consistently over the 10 years, and these suicides occurred most often in late spring and early summer. Within the 20-34 age group, individuals were more likely to commit suicide by gunshot wound (p = 0.000133). Decedents of minority ethnic and racial groups had lower education attainment compared to non-Hispanic (p = 0.000027) or white (p = 0.003314) individuals. This information could be provided to local schools with the hopes of implementing more targeted preventative measures for at-risk groups. Knowledge of suicide patterns in healthcare could lead to improved care for patients. Finally, public health entities can use these findings to adapt current health initiates to fit the needs of Allen County.

Spatio-temporal characteristics and driving factors of flash drought in northern China from 1978 to 2020

In recent years, studies have found that drought can occur rapidly under anomalous atmospheric circulation patterns and underlying surface conditions. This type of drought is defined as “flash drought”. It is more sensitive to global warming compared to traditional drought and may become a common drought phenomenon in the future and require intensive research. But the characteristics and development mechanism of flash drought in northern China has been studied much less than in southern China, and thus deserve further study. Based on the daily station data and GLDAS grid data from 1978 to 2020, this paper identified the flash drought in northern China, analyzed its evolution of temporal-spatial characteristics and explored the meteorological driving factors of flash drought. The main results are as follows: (1)The frequency of flash drought in the year is the highest in WNW (West of Northwest), followed by ENW (East of Northwest), NC (North China) and NE (Northeast China), while the frequency in the plant growing season is the highest in the south of NE and the south of NC, and low in the other regions. (2)The hotspot areas of flash drought showed an obvious eastward trend from WNW to ENW in northern China from the 1980s to 2010s. (3) There is a good relationship between soil moisture and precipitation in WNW and ENW, while the soil moisture is affected by both temperature and precipitation in NC and NE. (4) Flash drought could occur all through the year in WNW and NC, while it mainly occurred in the summer half-year and summer in EWN and NE. The main high occurrence period of flash drought in each region is in late spring and early summer, while a second high occurrence period appears from early September to late October in WNW. (5) From the perspective of the driving of water vapor changes, the flash drought in WNW and ENW is mainly driven by water vapor advection, while that in NC and NE is mainly driven by wind field divergence.

Antarctic polar vortex dynamics in 2019 and 2020 under the influence of the subtropical stratosphere

The trend of strengthening of the Antarctic polar vortex in late spring and early summer (November–December) has been observed in recent decades. A good example of this trend is the dynamics of the Antarctic polar vortex in 2020 when it existed until the last week of December. In 2019, conversely, on the contrary, an unusually early breakup of the polar vortex occurred, a minor sudden stratospheric warming was recorded. Strengthening (or weakening) of the Antarctic polar vortex occurs as a result of an increase (or decrease) in the stratospheric meridional temperature gradient under conditions of growth (or decline) in the temperature of the lower subtropical stratosphere. We considered the temperature variations in the lower subtropical stratosphere in the spring of 2019 and 2020 and the corresponding response of the Antarctic polar vortex. The dynamics of the Antarctic polar vortex in September–October 2019 and November 2020 was largely synchronized with the temperature changes in the lower subtropical stratosphere relative to climatological means. Using correlation analysis, we show that the Antarctic polar vortex dynamics in December is largely due to the temperature changes in the lower subtropical stratosphere that occurred in the second half of November, which manifested itself in 2020.

Seasonal Variability of Near-Inertial/Semidiurnal Fluctuations and Turbulence in the Subarctic North Atlantic

Abstract Six profiling floats measured water-mass properties (T, S), horizontal velocities (u, υ), and microstructure thermal-variance dissipation rates χT in the upper ∼1 km of the Iceland and Irminger Basins in the eastern subpolar North Atlantic from June 2019 to April 2021. The floats drifted into slope boundary currents to travel counterclockwise around the basins. Pairs of velocity profiles half an inertial period apart were collected every 7–14 days. These half-inertial-period pairs are separated into subinertial eddy (sum) and inertial/semidiurnal (difference) motions. Eddy flow speeds are ∼O(0.1) m s−1 in the upper 400 m, diminishing to ∼O(0.01) m s−1 by ∼800-m depth. In late summer through early spring, near-inertial motions are energized in the surface layer and permanent pycnocline to at least 800-m depth almost simultaneously (within the 14-day temporal resolution), suggesting rapid transformation of large-horizontal-scale surface-layer inertial oscillations into near-inertial internal waves with high vertical group velocities through interactions with eddy vorticity gradients (effective β). During the same period, internal-wave vertical shear variance was 2–5 times canonical midlatitude magnitudes and dominantly clockwise-with-depth (downward energy propagation). In late spring and early summer, shear levels are comparable to canonical midlatitude values and dominantly counterclockwise-with-depth (upward energy propagation), particularly over major topographic ridges. Turbulent diapycnal diffusivities K ∼ O(10−4) m2 s−1 are an order of magnitude larger than canonical midlatitude values. Depth-averaged (10–1000 m) diffusivities exhibit factor-of-3 month-by-month variability with minima in early August.

Rainy season onset date in Southwest China and the related atmospheric circulations

The rainy season onset date (RSOD) in the Southwest China (SWC) has important guiding significance for agricultural planting, and the abnormal RSOD is easy to cause drought or flood disasters in late spring and early summer. However, the RSOD in SWC and its related atmospheric circulation on daily scale and large regional scale has been less explored in the past literature. Therefore, this study aims to explore the circulation characteristics of RSOD on a daily scale in the whole SWC using the long-term observation and reanalysis datasets from 1961 to 2021. Results revealed that the RSOD in SWC advances from the east toward the west, with an average RSOD of May 27 and a standard deviation of 9.19 days. It is found that from around 10 days before the RSOD, the intensity of the India-Burma Trough and the Somali cross-equatorial jet stream were enhanced; the East Asian subtropical westerly jet begin to southward shift, which bring the upward movement, water vapor accumulation and the intersection of cold and warm air in southwest China, causing an earlier onset of rainy season in SWC. Moreover, May 5–25 are crucial to the early or late onset of the rainy season in SWC. When an anomalous zonal dipole of geopotential height in the upper level and an anomalous meridional dipole of geopotential height in the lower level occurred in May 5–25, the rainy season onset earlier. The atmospheric circulation changes approximately 10 days before the RSOD, and the anomalous circulation modes revealed in this study are of great importance for the prediction of RSOD in SWC.

Seasonal Susceptibility of Sweet Cherry Pruning Wounds to Calosphaeria pulchella, Cytospora sorbicola, and Eutypa lata.

Fungal canker pathogens commonly infect trees at pruning wounds leading to branch dieback and loss of productivity in sweet cherry orchards. However, the seasonal susceptibility of sweet cherry pruning wounds to Calosphaeria pulchella, Cytospora sorbicola, and Eutypa lata is not well understood. This study compared the susceptibility of sweet cherry pruning wounds made during the dormant season (January) and the postharvest season (late May to June) to infection by main canker pathogens in California. Field trials were conducted in three cherry orchards and trees were pruned at the different periods over 2 years. Fresh pruning wounds were inoculated with spores of each pathogen, and pathogen recovery was assessed through microbiological isolations at 3 to 4 months after inoculations. Pruning wounds made in late May and June resulted in significantly higher infection by Cal. pulchella compared to pruning wounds made in January. Pruning wounds made during both seasons were generally equally susceptible to Cyt. sorbicola and E. lata infections. However, there was one orchard where dormant pruning wounds were more susceptible to infection by E. lata and there was one particularly cold winter where Cyt. sorbicola did not infect pruning wounds. Overall, our findings suggest that Cal. pulchella infections of cherry pruning wounds are more likely to occur during periods of warm temperatures such as late spring and early summer. However, infections by Cyt. sorbicola and E. lata can occur year-round if inoculum is present and if winter temperatures are not abnormally low for California. Finally, our results suggest that the emergence of Cal. pulchella as a major canker pathogen of sweet cherry in California may be the result of a shift from dormant to after-harvest pruning of sweet cherry trees.

Study on O3 Variations in Nanjing and the Surrounding Source Analysis

To understand the transport patterns and major sources of ozone (O3) in Nanjing, this study carried out the 48-hour backward trajectories of air masses in Nanjing from March 2021 to March 2022, based on the HYSPLIT backward trajectory model driven by GDAS global reanalysis data. The primary transmission routes and putative source locations of O3 pollution in Nanjing were determined through the integration of trajectory clustering analysis, potential source contribution function (PSCF), and concentration-weighted trajectory (CWT) analysis with meteorological data and O3 concentration data. The results showed that the high O3 concentrations and exceedance rates in Nanjing were in late spring and early summer, with the highest in June. The diurnal variation of O3 concentrations in all seasons exhibited a single peak with a maximum from 13:00 to 16:00. The southeasterly flow passing through Zhenjiang, Changzhou, Wuxi, Suzhou, and Shanghai dominated the O3 pollution in Nanjing. The PSCF and CWT presented a high consistency of O3 potential sources in Nanjing. Zhenjiang, Ma’anshan, Changzhou, Wuxi, Suzhou, and Huzhou were identified as the main potential source regions of O3 pollution in Nanjing. This study provides accurate theoretical references for regional joint prevention and control of O3 pollution in Nanjing.

Seasonal occurrence of toxic phytoplankton and phycotoxins at a mussel aquaculture site in Nova Scotia, Canada

A three-year field study at a mussel (Mytilus edulis) aquaculture site in Ship Harbour, Nova Scotia, Canada was carried out between 2004 and 2006 to detect toxic phytoplankton species and dissolved lipophilic phycotoxins and domoic acid. A combination of plankton monitoring and solid phase adsorption toxin tracking (SPATT) techniques were used. Net tow and pipe phytoplankton samples were taken weekly to determine the abundance of potentially toxic species and SPATT samplers were deployed weekly for phycotoxin analysis. Mussels were also collected for toxin analysis in 2005. Liquid chromatography–tandem mass spectrometry (LC–MS/MS) was used to analyse the samples for spirolides (SPXs), pectenotoxins (PTXs), okadaic acid group toxins (OA, DTXs) and domoic acid (DA). Phycotoxins were detected with SPATT samplers beginning from the time of deployment until after the producing organisms were no longer observed in pipe samples. Seasonal changes in toxin composition occurred over the sampling period and were related to changes in cell concentrations of Alexandrium Halim, Dinophysis Ehrenberg and Pseudo-nitzschia (Hasle) Hasle. Spirolides peaked in late spring and early summer, followed by DA in mid-July. Okadaic acid, DTX1 and PTXs occurred throughout the field season but peaked in late summer. Concentrations of some phycotoxins detected in SPATT samplers deployed within the area where mussels were suspended on lines were lower than in those deployed outside the mussel farm. The SPATT samplers provided a useful tool to detect the presence of phycotoxins and to establish trends in their appearance in the Ship Harbour estuary.

Assessment of tropospheric ozone simulations in a regional chemical transport model using GEOS-Chem outputs as chemical boundary conditions

Regional chemical transport models (e.g., Community Multiscale Air Quality (CMAQ) Modeling System) are widely used to simulate the physical and chemical process of regional ozone (O3) pollution and its variation trend in recent years. However, chemical boundary condition (CBC) is an important input of these models and contributes to the model bias against observations. In this study, we develop a tool named GC2CMAQ that provides the CMAQ model with the CBCs from the GEOS-Chem simulation. Two experiments using different CBCs were conducted to evaluate their effect on seasonal O3 simulation in China. The Default experiment utilized the model-default static condition (the relatively clean atmosphere in the eastern United States), and the GC experiment employed the GEOS-Chem simulation results. Compared with the observation, the GC experiment has a much better performance in reproducing elevated O3 levels in the higher troposphere and lower stratosphere during different seasons. Near the earth's surface, the simulated concentrations of pollutants O3 (and PM2.5) in the GC experiment were also closer to the observation in April and July. The accuracy of simulation results in provinces close to the boundary was improved by approximately 20 %–30 % relative to the Default experiment. The CBCs provided by GEOS-Chem enabled a better simulation of stratosphere-troposphere O3 exchange in late spring and early summer, which then affected the pollutant concentration near surfaces through vertical transport. This finding was confirmed by a case study in southwestern Tibet on April 28, 2017, in which we quantified the contributions of different physical and chemical processes to O3 variations at different altitudes using the process analysis method. This study highlights the importance of using a reliable CBC for the regional chemical transport model to derive a better performance of O3 simulation.

The essential habitat role of a unique coastal inlet for a widely distributed apex predator.

Essential habitats support specific functions for species, such as reproduction, feeding or refuge. For highly mobile aquatic species, identifying essential habitats within the wider distribution range is central to understanding species ecology, and underpinning effective management plans. This study examined the movement and space use patterns of sevengill sharks (Notorynchus cepedianus) in Caleta Valdés (CV), a unique coastal habitat in northern Patagonia, Argentina. Seasonal residency patterns of sharks were evident, with higher detectability in late spring and early summer and lower during autumn and winter. The overlap between the residency patterns of sharks and their prey, elephant seals, suggests that CV functions as a seasonal feeding aggregation site for N. cepedianus. The study also found sexual differences in movement behaviour, with males performing abrupt departures from CV and showing increased roaming with the presence of more sharks, and maximum detection probability at high tide. These movements could be related to different feeding strategies between sexes or mate-searching behaviour, suggesting that CV may also be essential for reproduction. Overall, this study highlights the importance of coastal sites as essential habitats for N. cepedianus and deepens our understanding of the ecological role of this apex predator in marine ecosystems.

Quantifying Photovoltaic surplus at an urban scale: A case study in Seoul

With the increasing photovoltaic (PV) penetration in urban buildings, the temporal overproduction of PV electricity presents both a challenge and an opportunity for solar energy utilization in high-PV-penetration urban environments. While existing research has focused on strategies for improving self-consumption, little to no information exists on the magnitude and implications of PV surplus at the urban level. Questions such as when and where PV surplus occurs in the urban area remain unanswered, and there is a lack of established knowledge about how urban contexts relate to PV surplus. Therefore, this study aimed to quantify the PV surplus in a high roof-PV penetration scenario at an urban scale, using a method that couples hourly PV production and electricity consumption data from individual buildings in urban areas. The paper explored two aspects of PV surplus, namely PV surplus hours (PVsH) and PV surplus energy (PVsE), which were utilized to identify the temporal occurrence and quantify the amount of PV surplus, respectively. One residential and one office area in Seoul were examined. Results showed abundant PV surplus resources in case areas, especially in residential buildings. A wide range of surplus distribution was found among the buildings, especially in the office area. The PV surplus peaked between late spring and early summer. A noticeable correlation between building morphology and PVsE was detected. The results suggested the PV surplus of the residential area is sufficient for localizing charging demand by comparing PV surplus against the electricity demand from a hypothetical scenario of a full electric vehicle (EV) community.

The Effect of Month and District on 100-Day In-Calf Rate in Year-Round Calving Dairy Herds.

Monitoring 100-day in-calf rate (100DICR) is an integral part of the assessment of reproductive performance in year-round calving dairy herds. The objective of this study was to investigate the effect of month on 100DICR in year-round calving herds in New South Wales (NSW), Australia and determine whether a fluctuating 100DICR target is an appropriate alternative to a constant 100DICR target. The 100DICR is defined as the percentage of all current lactating cows over 100 days in milk (DIM) that conceive on or before 100 DIM. As dairy cows are typically dried off 7 months after conception, 100DICR was an approximate 7-month rolling average. Mean monthly 100DICRs were calculated with a generalised linear model for six NSW north coast herds located 15-140 km from the coast and four NSW south coast herds located less than 10 km from the coast, over a two-year period. The mean 100DICR was lowest in May at 28.62% (95%CI 28.31-28.93) and increased during winter and spring, peaking in December at 34.74% (95%CI 34.32-35.15). The observed trend was similar for north and south coast herds, although north coast herds experienced a greater change in 100DICR from the peak to a nadir of 27.58% (95%CI 27.18-27.98), a 7.15-point difference, compared to south coast herds with a nadir of 30.18% (95%CI 29.69-30.67), a 4.67-point difference between the peak and nadir. In conclusion, 100DICR is affected by month with the lowest 100DICRs observed in late autumn and the highest 100DICRs observed in late spring and early summer. Therefore, a fluctuating target 100DICR is an appropriate alternative to a constant target when assessing reproductive performance in year-round calving herds. While the district does not affect mean 100DICR per se, the district does affect the difference between peak and nadir 100DICR.

Temporal and small-scale spatial variation in spatfall of the mussel Mytilus edulis platensis: Basis for culture management at San Jorge Gulf, Patagonia Argentina

Despite the commercial potential of mussel populations along the Patagonian coast of Argentina, studies on mussel farming and fisheries to the south of parallel 42° S are clearly insufficient thus far. In this study, variations in mussel settlement (between sites and across depths) were monitored for 12 months at two contrasting sites in San Jorge Gulf, Argentina. The effect of depth on spat density was evaluated through monthly samples taken from artificial collectors at three depths (3, 7 and 11 m). The temporal settlement pattern was consistent at both sites, with the maximum spatfall recorded in early March (late summer), coinciding with the peak of sea water temperature. Settlement also correlated with Chl a and particulate organic carbon peak values, typically manifesting 2–3 months later and followed the initial decline in mussel condition during late spring and early summer. Significant differences between localities were detected in settlement abundance. The optimal temporal gap for mussel settlement was observed in mid / late summer, suggesting that this is the optimal time to deploy spat collectors in the field. Settlement was uniform between depths, thereby implying that the specific depth of collector placement did not appear to emerge as a key factor of settlement success.

High Productivity at High Latitudes? Photosynthesis and Leaf Ecophysiology in Arctic Forests of the Eocene

AbstractThe Arctic forests of the Eocene, which thrived under elevated CO2, a temperate climate, high precipitation and annually extremely different daylengths, represent a quite spectacular no‐analogue habitat of Earth's greenhouse past. The aim of this study was to improve our understanding of the ecophysiology of Arctic broad‐leaved deciduous forests of the Eocene, by analyzing leaf photosynthesis and tree productivity based on gas exchange modeling for two fossil Eocene sites, Svalbard and Ellesmere Island. For this, a single‐leaf photosynthesis model that includes heat transfer and leaf senescence was derived. Environmental conditions were based on available palaeoclimate data and a CO2 level of 800 μmol/mol. Additionally, different light regimes (diffusivity and transmissivity) were considered. With this model, annual photosynthesis was calculated on the basis of annual temperature and day lengths (derived by celestial mechanics). To obtain productivity of a whole deciduous broad‐leaved tree, the single leaf data were then upscaled by a canopy model. The results indicate that productivity was enhanced at both high latitude sites by elevated CO2, temperature of the growing season and high maximum daylength (24 hr) during late spring and early summer. With productivity values about 30%–60% higher as for a mid‐latitude continental European forest, the results indicate a potential for high productivity at the Eocene polar sites which is in the range of extant tropical forests. In contrast to speculations, no evidence for a selective advantage of large leaf size—as shown by various fossil leaves from high latitude sites—could be found.

Flower visits of cockroaches (Insecta: Blattodea) in the Iberian Peninsula: Are they neglected pollinators?

AbstractAlthough several insect orders have been deeply studied in plant–animal interactions (e.g. pollination) cockroaches have traditionally been ignored in taxonomic and ecological studies. However, they could be playing a role in the reproduction of several plants. To date, 8 plant species use cockroaches as a pollination agent. In our study, we have reviewed 2865 records from citizen science platforms and our own data from the Iberian Peninsula to find flower visits made by cockroaches. We have detected 51 interaction records involving at least 8 different cockroach species and 35 plant species. Furthermore, nearly half of the detected cockroaches carried pollen on various parts of their bodies. These insects were found to mainly visit white, yellow and pink flowers from Apiaceae, Asteraceae and Cistaceae plant families (among others) mainly in late spring and early summer. However, for the confirmation of effective pollination, new studies must be carried out. Additionally, although the existence of pollination syndrome is far from being understood, we provide new insights that could help shed some light on this unknown relationship. Here we provide the first approximation of cockroach floral perception and we have detected that white flowers show the best fit and higher conspicousness to cockroach colour vision, as suggested for other neglected pollinator insects.