August Temperature Research Articles

Temperature sensitivity of blue intensity, maximum latewood density, and ring width data of living black spruce trees in the eastern Canadian taiga

The blue intensity (BI) technique provides opportunities to obtain surrogates to tree-ring density for reconstructing summer temperatures in high-latitude regions. In this study, we compare latewood BI (LBI) and delta BI (DBI), with the conventional X-ray maximum latewood density (MXD) and tree-ring width (TRW) data using 178 living trees of black spruce (Picea mariana (Mill.) B.S.P.), one of the most dominant species of conifers in the Northern Hemisphere, from 17 sites across the eastern Canadian taiga. The regional LBI and DBI chronologies are highly correlated to that of MXD (Pearson’s r = 0.97 and 0.92, respectively), while DBI is also similar to TRW (Pearson’s r = 0.67). Both LBI and DBI exhibit stronger responses to the May–August temperatures than TRW over larger time and spatial scales. However, only DBI is comparable to MXD data from inter-annual to decadal timescales. Low-frequency components of LBI data are likely distorted by color biases even if no obvious discoloration is present, as well as by the potentially low measurement resolution, leading to an overall weaker temperature sensitivity compared to the MXD data. Resampling experiments suggest that a minimum replication of 10 trees is needed to retain ≥90 % of the optimal temperature signal for MXD, LBI, and DBI data, and a minimum of 20 trees is required for TRW data.

Prominent role of volcanism in Common Era climate variability and human history

Climate reconstructions for the Common Era are compromised by the paucity of annually-resolved and absolutely-dated proxy records prior to medieval times. Where reconstructions are based on combinations of different climate archive types (of varying spatiotemporal resolution, dating uncertainty, record length and predictive skill), it is challenging to estimate past amplitude ranges, disentangle the relative roles of natural and anthropogenic forcing, or probe deeper interrelationships between climate variability and human history. Here, we compile and analyse updated versions of all the existing summer temperature sensitive tree-ring width chronologies from the Northern Hemisphere that span the entire Common Era. We apply a novel ensemble approach to reconstruct extra-tropical summer temperatures from 1 to 2010 CE, and calculate uncertainties at continental to hemispheric scales. Peak warming in the 280s, 990s and 1020s, when volcanic forcing was low, was comparable to modern conditions until 2010 CE. The lowest June–August temperature anomaly in 536 not only marks the beginning of the coldest decade, but also defines the onset of the Late Antique Little Ice Age (LALIA). While prolonged warmth during Roman and medieval times roughly coincides with the tendency towards societal prosperity across much of the North Atlantic/European sector and East Asia, major episodes of volcanically-forced summer cooling often presaged widespread famines, plague outbreaks and political upheavals. Our study reveals a larger amplitude of spatially synchronized summer temperature variation during the first millennium of the Common Era than previously recognised.

Surveying topographical changes and climate variations to detect the urban heat island in the city of Málaga (Spain)

The main aim of this research was to detect a possible urban heat island (UHI) in the tourist city of Málaga (Spain). To achieve this goal, different methods to validate annual and monthly temperature data have been used, and the internal variability of the UHI with respect to the topographical changes was also surveyed. Our results showed two types of atmospheric thermal gradients: one characterized by a positive gradient according to an elevation above sea level, and another with a negative gradient related to rural areas. The maximum impact of the UHI was found to be 9.1 ºC for an instantaneous event, 4.4 ºC for daily minimum temperatures in August, with a maximum weighted average difference of 2.3 ºC between data from urban and rural stations. We conclude that the detection of UHI is useful as a tool to help urban planners, in order to reduce the intensity of possible climate changes in cities. It is also concluded that UHI is not only a meteorological phenomenon in Málaga city but a climatic phenomenon, present during most days and across the transect of increasing intensity from the sea to the city.

Effects of Environmental Factors on the Abundance, Biomass, and Individual Weight of Juvenile Red King Crabs in the Barents Sea

We examined the effeсts of environmentаl fаctоrs (water temperature, the North Atlantic Oscillation winter index – NAOw, and cod biomass) on the abundance (population number), biomass and mean individual weight of juvenile red king crab (Paralithodes camtschaticus) at a typical coastal site of the Barents Sea, Dalnezelenetskaya Bay, a place of red king crab introduction. Current-year abundance and stock data for 3–5-year-old crabs were positively related to water temperature in September and October. The biomass of crabs at age 0–2 yr was positively correlated with lag 1 water temperature in August, while the abundance of age 0–5 yr was positively correlated to the NAOw indicating more favorable habitat conditions in warmer periods. The abundance of crabs at age 3–5 yr was negatively correlated to December temperature and mean water temperature and temperature anomaly with a 1-year lag. These temperature relationships, together with negative correlations between stock indices of crabs and cod (Gadus morhua) and positive relationships between mean crab weight and cod biomass, suggests that the fish predation, which is higher in warmer years, has a more important role in mortality of 3–5 yr crabs than 0–2 yr crabs. Our findings may be useful for modeling recruitment processes and management of red king crab in the Barents Sea.

A 324-years temperature reconstruction from Pinus latteri Mason at highland in Chiang Mai Province, Thailand

Abstract. Lumyai P, Palakit K, Suangsathaporn K, Wanthongchai K. 2020. A 324-years temperature reconstruction from Pinus latteri Mason at highland in Chiang Mai Province, Thailand. Biodiversitas 21: 3938-3945. The objective of this study was to investigate the relationship between the growth of Pinus latteri and climate data in Chiang Mai Province, Thailand. Dendrochronological techniques were used to analyze 35 sample cores. The cross dated ring width data could be extended back for up to 324 years (1692-2015). The relationship between ring-width index and climate data indicated a significant correlation (p < 0.01) with the monthly rainfall in January, monthly temperature in August and September, extreme maximum temperature in August and mean maximum temperature in March and August. The reconstructed average monthly temperature in August was estimated at around 27.35 °C, a warming period could have occurred in 1694-1702, 1834-1844, 1848-1866, 1873-1876, 1884-1890, 1896-1902, 1911-1927, 1942-1958, and 1986-1990, with cooling periods occurring in 1703-1722, 1739-1752, 1865-1872, 1877-1883, 1891-1895, 1903-1910, 1928-1941, 1959-1961, and 1968-1970, which could explain the high fluctuations in temperature. Periods in the range 2.1-2.5, 10.1 , and 13.5 years were found to be common with the variations in El Niño-Southern Oscillation. In conclusion, the pine growth information can be used to monitor the variations in climate in Thailand.

First Report of Leaf Spot Caused by Alternaria alternata on Anemone japonica in Italy

Anemone japonica L. (Japanese windflower) is a late summer flowering perennial ornamental belonging to the Ranunculaceae. In August 2019, symptoms of a leaf spot were observed on 10-year-old plants, growing in a private garden located near Biella in northern Italy (45°36′00″N, 8°03′00″E). Initial infections appeared as brown to black, circular to oval spots, 5 to 30 mm in diameter, present on both leaf surfaces. Leaf spots gradually developed concentric rings, which then coalesced into large infected areas, resulting in defoliation. At temperatures ranging between 15 and 28°C (average monthly temperature in August of 24°C), 25 to 30% of about 100 plants were affected. Isolations of the causal agent were made by excising infected leaf tissue pieces, previously immersed in a solution containing 1% sodium hypochlorite for 1 min, rinsing in sterile tap water, and placing them on potato dextrose agar (PDA) amended with 25 mg/liter streptomycin sulfate. PDA plates were incubated for 5 days at 20 to 22°C with 12 h of daylight, after which olivaceous to black fungal colonies developed on 90% of the plates. Monoconidial cultures of two fungal isolates were designated 19-51-31 and 19-51-36. On potato carrot agar (Simmons 2007), the two isolates incubated for 10 days at 22°C with 8 h of daylight developed multicellular, obclavate to obpyriform brown conidia that were produced on branched conidiophores, and measured 49 to 115 μm long × 2.4 to 4.7 μm wide, presenting a similar sporulation pattern as for group 4 (Simmons and Roberts 1993). Conidia were formed mainly in chains of 10 to 14 and measured 11.5 to 42.0 µm (average 27.7 µm, n = 40) in length and 3.2 to 13.9 µm (average 9.9 µm, n = 40) in width. Conidia contained zero to three longitudinal and two to five transverse septa, and, when present, beaks measured 0.9 to 10.5 µm. The fungus was identified as Alternaria sp. based on morphological characteristics (Simmons 2007). DNA extraction for molecular identification of the two fungal isolates was carried out using the E.Z.N.A. Fungal DNA Mini Kit (Omega Bio-Tek, Darmstadt, Germany). PCR assays were done using primers for ITS (White et al. 1990), rpb2, Alt a 1, endoPG, and OPA10-2 (Woudenberg et al. 2015). Sequences with 528 to 530 bp (ITS), 933 to 939 bp (rpb2), 439 to 444 bp (Alt a 1), 459 to 460 bp (endoPG), and 615 to 619 bp (OPA10-2) were obtained (GenBank accession nos. MT044149, MT043353, MT043357, MT185590, and MT043355 for fungal isolate 19-51-31; and MT044150, MT043354, MT043358, MT185591, and MT043356 for isolate 19-51-36, respectively). The sequences of both isolates using a BLASTn analysis showed 100% identity with the ex-type CBS 916.96 of Alternaria alternata (Fries) Keissler in ITS, rpb2, and Alt a 1 portions (accession nos. AF347031, KC584375, and AY563301, respectively) and 99% identity in endoPG and OPA10-2 portions (accession nos. JQ811978 and KP124632, respectively). Phylogenetic analysis of endoPG sequences grouped the 19-51-31 and 19-51-36 isolates with the reference isolates of A. alternata and not with the isolates of other Alternaria species. Pathogenicity tests were performed by spraying leaves of 1-year-old healthy potted A. japonica plants with spore suspensions of both fungal isolates that contained 10⁵ conidia/ml. Plants sprayed with tap water only served as negative controls. Five plants per treatment were used in tests carried out twice. Plants were covered with plastic bags for 5 days after inoculation and maintained in a glasshouse at temperatures ranging between 22 and 26°C. Leaf spots, similar to those observed on the garden plants, developed 7 days after inoculation. Control plants remained with no symptoms. To our knowledge, this is the first report of A. alternata on A. japonica in Italy, as well as worldwide. A. alternata previously has been reported on Anemone occidentalis in the United States (Woudenberg et al. 2015). The disease has appeared in several gardens on A. japonica, influencing floral characteristics and reducing market value.

Potential for offshore aquaculture development in North Korea: Focusing on Atlantic salmon farming

This study investigated the potential for Atlantic salmon farming in North Korea. Farmed Atlantic salmon (Salmo salar) are aquaculture products commonly consumed in East Asia, but they are not commercially produced in large quantities. One barrier to Atlantic salmon farming is that the marine environmental conditions (i.e., water temperatures) in much of East Asia are unsuitable. North Korea has recently initiated Atlantic salmon farming assuming it has appropriate locations for it. If North Korea indeed has suitable locations for successful Atlantic salmon aquaculture and the United Nations' sanctions were lifted, the country's Atlantic salmon farming project might have potential for successful inter-Korean economic collaborations. The current study analyzed North Korea's possible farming sites using remote sensing data, and it used those findings to evaluate the feasibility of inter-Korean Atlantic salmon fishery collaborations and to propose policy implications. Remote sensing information estimated sea surface temperatures and hydrodynamic modeling extended that to estimate the sea temperatures at various depths to precisely propose appropriate farming locations in North Korea. The results indicated that most of North Korea's sea surface temperatures were below 20 °C in January through June. However, the surface temperatures in July and August exceeded 20 °C, indicating unsuitability for Atlantic salmon farming during that period. The water temperatures at the 25-m depth were below 20 °C year round, and Atlantic salmon farming would be possible there using submersible farming technologies, such as plant-type offshore fish farming systems.

정기 환경조사 자료를 이용한 전남 양식어장 입지의 적합성 평가

This study was conducted to evaluate the locational suitability of aquaculture grounds in Jeonnam coastal area using seawater and sediment quality monitoring data from 2016 to 2018. It was evaluated that the water temperature of February and August in the inner area of Gamak, Yeoja, Deukryang, and Hampyung bay was not suitable for rockfish based on its tolerable temperature range. It is also revealed that the concentrations of dissolved inorganic nitrogen and phosphorus are lower than the suitable laver growth around the coast of Wando, Jindo, especially in Goheung during the culturing period. Moreover, it was evaluated that the status of sediment eutrophication in the inner area of Yeoja, Deukryang, and especially in Gamak bay could affect the growth of mussel or blood cockle by discharging unfavorable gas if anaerobic condition was formed.

Climate change signals in the historical water footprint of wheat production in Zimbabwe

Climate change has been posited as the biggest threat to crop productivity in agro-systems, yet its impact on the water footprints of crop production for many regions remains uncertain. This study sought to determine evidence of historical climate change (1980–2010) and its resultant impact on the blue water footprint of winter wheat production in Zimbabwe. The analysis involved assessing the impact of climate change on wheat yield and crop water requirements, the key factors determining the blue water footprint. The CROPWAT model and the global water footprint assessment (WFA) standard were used to calculate the blue water footprint. Multiple linear regression was used to correlate climate variables to wheat yield, crop water requirements and the blue water footprint. Results show a significant (p < 0.05) warming of temperatures in the country's main wheat growing areas. Crop water requirements for winter wheat decreased by 4.88%, due to positive and negative trends in humidity and wind speed respectively. Between 1980 and 2000 the coupled effects of solar radiation at anthesis and maximum temperatures in July, August and September reduced wheat yields by 6.65%. The cumulative effects of climate change on crop water requirements and wheat yields increased the blue water footprint by 4%. The results of the study suggest that climate change and agricultural management factors might be equally responsible for the increase in the blue water footprint.

Analysis of Urban Heat Islands Using Landsat 8 OLI / TIR Data: Case of the City of Guelma (Algeria)

This study aims to analyze the urban heat islands of the city of Guelma using Landsat 8 data and the geographic information system. The application of the single Chanel algorithm has been applied to extract surface temperature (LST) from Landsat 8 data. The result obtained shows that the surface temperature of August 11, 2019 in the city of Guelma varied from 36 to 47 degrees. However, the correlation between the LST, the NDVI and the NDBI allowed characterizing the effects of the green zones and the water resources thus the grounds built on the urban heat islands. The ecological assessment was performed using an urban thermal field variance index (UTFVI). The result obtained from this ecological assessment shows that 4 km2 of the surface of the city of Guelma represents a much worse ecological quality. It is therefore urgent for this city to strengthen and expand the strategies for reducing the effects of urban heat islands for preserve the quality of urban life of the inhabitants.

Determination of the Effect of Green Roofs on Indoor Temperature by the Use of Simulation in a Tropical Landscape

Aims: To use a simulation base exploration to carry out 6 scenarios of green roof construction methods to determine the most efficient in improving indoor thermal comfort.&#x0D; Study Design: Simulation Design was used as the study design.&#x0D; Place and Duration of Study: The study was conducted at the Department of Horticulture – Kwame Nkrumah University of Science and Technology located at Kumasi-Ghana between 2016 and 2019.&#x0D; Methodology: A simulation experimental setup was done to run for 1 year to cover the two seasons in Ghana. Version 5.0.2 Design Builder and Energy Plus 5.8 was used to work on 6 scenarios using leaf area indexes (LAI) of 2 and 5 as well as soil depth (thickness) of (70-150 mm), 200 mm, 300 mm and 500 mm. Also a real life experiment was done at the Department of Horticulture by constructing 9 test cells and using treatments such as Portulaca grandiflora and Setcreasea purpurea to validate the results for the simulation. The time setup for the simulation was from 12.00 am to 11.59 pm.&#x0D; Results: A leaf area indexes (LAI) of 5 and soil depth of 70 mm-150 mm recorded the lowest simulated temperature ranging from 26.26°C to 29.30°C for scenario one. For scenario two, a leaf area indexes (LAI) of 5 and a soil depth of 200mm recorded the lowest significantly (P≤0.05) indoor temperature in August (26.20°C) and the highest (29.26°C) in March. In February, June and August, significant differences (P≤0.05) were achieved by leaf area indexes (LAI) 5 and soil thickness 500 mm for scenario three. January, March to July indicated significant differences (P≤0.05) between the treatments leaf area indexes (LAI) 2 and soil thickness 300 mm and leaf area indexes (LAI) 5 and soil depth of 300 mm recorded 26.32°C to 29.33°C for August and March respectively for scenario four. A soil depth of 500 mm and leaf area indexes (LAI) of 2 gave significantly (P≤0.05) low temperatures indoors all year (26.27 to 29.32°C) for scenario five and in August leaf area indexes (LAI) 5 and soil thickness of 500 mm recorded the least temperature all year for scenario six.&#x0D; Conclusion: From the exploration, a soil depth of 70 mm – 150 mm and a LAI of 5, LAI of 5 and soil depth of 200 mm and LAI of 2 and soil depth of 500 mm achieved the lowest temperature and performed better in terms of temperature reduction which will lead to thermal comfort of occupants.

Change in photosynthetic pigments of Date palm offshoots under abiotic stress factors

Abstract Increasing world temperatures are bringing about climate changes creating abiotic stress in plants. Date palm offshoot leaves (Khadrawi cv.) were analyzed for chlorophyll Chl a, Chl b, Total Chl, Chl a/b ratio, anthocyanin and carotenoid subject to salinity, drought and temperature stress under field conditions. Results demonstrated that drought and salinity stress accompanied by high temperatures in July and August significantly reduced the Chl a, Chl b, and Total Chl relative to the control. Anthocyanins, carotenoids, hydrogen peroxide, and malondialdehyde were markedly higher in July and August (45 ºC), whereas September showed lower values in these substances. Temperature reduction to 35 °C accompanied by drought or salinity stress, brought about a critical increment in relative water content and a decrease in electrolyte leakage. Although the impact of drought and salinity stress continued, the reduced temperatures in September resulted in a reduction of abscisic acid and proline concentration. Cluster analysis showed the two groups. In this first group, the significant similarity between the treatments is illustrated by the influence of the high temperature of 43–45 ºC. Recovery of photosynthesis following low-temperature, for the most part, determines plant flexibility to water deficiencies and salinity. Thermal stress, associated with salinity or drought stress is more damaging to the photosynthetic pigments than any single factor.

MATHEMATICAL MODELS OF HIGH-STARCH MAIZE HYBRIDS OF DIFFERENT GROUND GROUPS

The article presents the results of mathematical modeling based on the construction and usage of different images of an object, process or system. The research expected to study the dependence of the productivity level and the economically valuable features of corn hybrids in the form of mathematical models. Field studies were carried out during 2011-2017 at the field of research of the Department of Plant, Selection and Bioenergy Crops of SE EF “Kordelivske” of IP NAASU of Vinnytsia National Agrarian University under the conditions of the Forest-Steppe of the Right-Bank, in accordance with the recommendations presented in the Methodology Of The Maize Field Study. The soils in the study variants are represented by black earth soil of deep medium loamy on the loessial soil. The humus content (according to Tiurin) in the tilth soil was 4.60%. Soil reaction - pH (salt) 5.7. The soils contain lightly hydrolyzed nitrogen (according to Kornfield) 106 mg per 1 kg of soil, mobile phosphorus and exchangeable potassium (according to Chirikov) 186 and 160 mg per 1 kg of soil, respectively. The experiments established the economic and biological evaluation of corn hybrids depending on the sowing period, the size of the fraction and the depth of seed wrapping, foliar fertilizers by micro fertilizers. The plot area for hybrids was 10.5 m2. Repeatability in experiments for hybrids is 3 times. Placement of plots is by the method of randomized blocks. An ecological-genetic model of quantitative features was used to study the phenotypic productivity of maize hybrids and to establish the influence on the formation of their traits. The model construction is based on the hierarchy of production traits demonstration in ontogeny and the correspondence of their manifestation in organogenesis. The model consists of three modules of features, i.e. the resultant and two components which reflecting the phenotypic implementation of the genetic formula. Resulting features are those that have an environmentally stable relationships and the highest total contribution to the intended property, yield. As a result of the conducted research, the mathematical models of the duration of the growing season of early-maturing maize hybrids allowed us to determine that the biggest influence does sums of effective temperatures (≥ + 10° C) for May, June, August and September over correlation rate at r = -0.62 and r = -0.51, r = 0.59 and r = 0.39, respectively. Also precipitation amount significantly influenced on the duration of the growing season and the correlation coefficient was r = -0.44, and the influence of the HTI was at the level of r = -0.34. For middle-early hybrids the sum of effective temperatures (≥ + 10° C) in May and June r = -0.46 and r = -0.28, respectively, and also the sum of effective temperatures (≥ + 10° C) in August – r = 0.18 had a strong effect. However, for medium-maturing maize hybrids, the duration of the growing season was determined by the sum of effective temperatures (≥ + 10° C) for May, June and July – r = -0.37, r = -0.34 and r = -0.28, and the sum of effective temperatures (≥ + 10° C) in August – r = 0,18. It is also possible to note the influence and the total sum of effective temperatures (≥ + 10° C) during vegetation at the level of correlation coefficient r = -0.51. According to the research results of mathematical models of the influence of weather conditions on the formation of phenotypic productivity of maize hybrids of different maturity groups both general biological regularities and group differences of features formation were established. Thus, if we analyze the differences between groups of early-ripening and middle-early corn hybrids, their growth and development in general are influenced by the sum of the effective temperatures, rainfall and HTI. In fact, the studied groups of ripeness differ slightly and the main differences are observed only in the variability of the studied features or their close relationship with each other. However, middle-aged hybrids respond somewhat differently to environmental factors, which allow developing the elements of adaptive growing technology for each of the maturity groups. Key words: corn, hybrid, phenotype, mathematical model, productivity, economic and valuable features.

Net Primary Productivity of Pinus massoniana Dependence on Climate, Soil and Forest Characteristics

Understanding the spatial variation of forest productivity and its driving factors on a large regional scale can help reveal the response mechanism of tree growth to climate change, and is an important prerequisite for efficient forest management and studying regional and global carbon cycles. Pinus massoniana Lamb. is a major planted tree species in southern China, playing an important role in the development of forestry due to its high economic and ecological benefits. Here, we establish a biomass database for P. massoniana, including stems, branches, leaves, roots, aboveground organs and total tree, by collecting the published literature, to increase our understanding of net primary productivity (NPP) geographical trends for each tree component and their influencing factors across the entire geographical distribution of the species in southern China. P. massoniana NPP ranges from 1.04 to 13.13 Mg·ha−1·year−1, with a mean value of 5.65 Mg·ha−1·year−1. The NPP of both tree components (i.e., stem, branch, leaf, root, aboveground organs, and total tree) show no clear relationships with longitude and elevation, but an inverse relationship with latitude (p &lt; 0.01). Linear mixed-effects models (LMMs) are employed to analyze the effect of environmental factors and stand characteristics on P. massoniana NPP. LMM results reveal that the NPP of different tree components have different sensitivities to environmental and stand variables. Appropriate temperature and soil nutrients (particularly soil available phosphorus) are beneficial to biomass accumulation of this species. It is worth noting that the high temperature in July and August (HTWM) is a significant climate stressor across the species geographical distribution and is not restricted to marginal populations in the low latitude area. Temperature was a key environmental factor behind the inverse latitudinal trends of P. massoniana NPP, because it showed a higher sensitivity than other factors. In the context of climate warming and nitrogen (N) deposition, the inhibition effect caused by high temperatures and the lack or imbalance of soil nutrients, particularly soil phosphorus, should be paid more attention in the future. These findings advance our understanding about the factors influencing the productivity of each P. massoniana tree component across the full geographical distribution of the species, and are therefore valuable for forecasting climate-induced variation in forest productivity.

Some (do not) like it hot: shrub growth is hampered by heat and drought at the alpine treeline in recent decades.

Mountain ecosystems are particularly sensitive to climate change. However, only a very small number of studies exist so far using annually resolved records of alpine plant growth spanning the past century. Here we aimed to identify the effects of heat waves and drought, driven by global warming, on annual radial growth of Rhododendron ferrugineum. We constructed two century-long shrub ring-width chronologies from R. ferrugineum individuals on two adjacent, north- and west-facing slopes in the southern French Alps. We analyzed available meteorological data (temperature, precipitation and drought) over the period 1960-2016. Climate-growth relationships were evaluated using bootstrapped correlation functions and structural equation models to identify the effects of rising temperature on shrub growth. Analysis of meteorological variables during 1960-2016 revealed a shift in the late 1980s when heat waves and drought increased in intensity and frequency. In response to these extreme climate events, shrubs have experienced significant changes in their main limiting factors. Between 1960 and 1988, radial growth on both slopes was strongly controlled by the sum of growing degree days during the snow free period. Between 1989 and 2016, August temperature and drought have emerged as the most important. Increasing air temperatures have caused a shift in the growth response of shrubs to climate. The recently observed negative effect of high summer temperature and drought on shrub growth can, however, be buffered by topographic variability, supporting the macro- and microrefugia hypotheses.

Climatic Causes of Plant Flowering Time Displacement in the Central Forest Reserve

Meteorological series and phenological data in the framework of our environmental monitoring in the South taiga Central Forest Reserve were analyzed. During 1984– 2017, the average annual air temperature was 4.63±0.41°C, and the average annual rainfall was 2.14±0.12 mm/day. For eight of the 43 (19%) climatic parameters, reliable linear trends of variability were found: an increase of air temperature in July, August, September, and December; an increase of soil temperature in December; an increase of precipitation in November and December; and a decrease of precipitation in September. Three causes of their directed long-term changes were revealed, namely: a shift of the winter timing, violation of the annual dynamics of climatic parameters and a change in the precipitation type during a longer autumn – snow to be replaced by rain. Of the 11 species of vascular plants, the statistical significance of the long-term displacement of phenological dates was proven for Anemone nemorosa: the longer the autumn and softer the beginning of the winter, the earlier the onset of its flowering. Two classification types of vascular plants in identifying interspecific synchrony in the phenological events variation were considered. Variability components of phenological phenomena occurrence was estimated: the share of long-term trends of the shift in phenological dates timing due to changes in reserve climatic system is from 20 to 68% of the total sign dispersion; interannual climatic fluctuations explain 5–34% of its variability; and the proportion of variability under unaccounted factors influence is high (21–64%). Species with a high proportion of their long-term variability components (Anemone nemorosa: more than 60%) are recommended to use as indicators of climate change under the conditions of the study area.

Drought/wetting variations in a semiarid and sub-humid region of China

It has been widely accepted that the global climate will change, with a ‘dry gets drier, wet gets wetter’ pattern. Recent studies found that such changes were overestimated. Drought/wetting variations were detected in a semiarid and sub-humid transitional region of China. The aridity index based on precipitation and reference evapotranspiration was applied to estimate drought/wetting variations. The results showed that the climate in the annual mean of the Zhangjiakou region showed a wetting trend from 1960 to 2017. The wetting trend also occurred in January, February, May and the wet season, especially in June, and in September, October, December and the dry season, and the wetting trend was significant. However, the drought trend occurred in March, April, July, August and November. Moreover, the most obvious wetting and drought changes occurred in September and August, respectively. Climate drought/wetting conditions are primarily driven by precipitation. Although increasing temperatures resulted in enhanced evaporation, precipitation increased, which could offset the increase in evaporation. In addition to precipitation and temperature, humidity was an important influencing factor on drought/wetting variation. The impact of humidity on drought/wetting conditions was greater than that of temperature in January, February, July, August and September. The influencing factors of drought/wetting variations are complicated in the Zhangjiakou region and are mainly influenced by the southeast monsoon, southwest monsoon and plateau monsoon in the Tibetan Plateau, westerly circulation and West Pacific subtropical high.

Association between Japanese cedar and cypress pollen counts and climate factors over a 10-year period in Tsu city, Japan

Japanese cedar pollen and cypress pollen are the most common causes of seasonal allergic rhinitis in Japan. In the present study, we examined the relationship between climate factors and Japanese cedar and cypress pollen counts in Tsu city, Mie prefecture, Japan. Cedar and cypress pollen measurements were taken between 2009 and 2018 using a gravitational method (Durham’s sampler). Each year, during this 10-year period, measurements were taken daily from the beginning of February until the middle of May. The relationship between cedar and cypress pollen counts and the highest temperature, sunshine duration, and average humidity of a given year and the previous year were analyzed using multiple linear regression analysis. Sunshine duration in April of a given year and November of the previous year and average humidity in August of the previous year were associated with cedar and cypress pollen counts (R2 = 0.980, p < 0.000). Sunshine hours in April of a given year and temperature in August of the previous year were associated with cypress pollen counts; however, the temperature in October of the previous year was not (R2 = 0.872, p < 0.001). In addition, the temperature in January of a given year had an inverse association with cedar pollen counts (R2 = 0.338, p < 0.045). Thus, the evaluation of cedar and cypress pollen counts and weather conditions in Tsu city will provide valuable information to physicians for predicting pollen prevalence and treating patients with allergies effectively.

First measurements of Blue intensity from Pinus peuce and Pinus heldreichii tree rings and potential for climate reconstructions

Climate changes, their regional patterns, origin, and prediction are currently one of the most important scientific challenges. Tree-rings are among the most widely used proxies for past climate variation. However tree-ring width (TRW) from certain tree species and regions often do not contain robust climate signal. Other parameters such as Maximum latewood density (MXD) of conifer tree rings are more sensitive to summer temperatures, but the measurements have high costs. A potential surrogate for MXD is blue intensity (BI), which is based on the measurements of high-resolution images of the wood. The method has been tested and applied for several species. However it has not been tested up to now for Pinus heldreichii Christ (PIHE) and Pinus peuce Griseb. (PIPE). Those species are with limited distribution on the Balkan Peninsula and due to their longevity (frequently more than 500 years with potential to more than 1000 years) may serve as one of the best proxies for past climate variation in SE Europe.We composed BI chronologies following standard procedures from PIHE and PIPE trees from subalpine locations in the Pirin Mts, Bulgaria. The correlation analysis with climate parameters revealed strong and significant positive correlations of PIHE BI (ΔBI and Latewood BI (LwBI) series) and summer temperatures. The highest were 0.74 (p < 0.05) with July-August average temperatures for the period 1933–1983. The correlation values of ΔBI remained higher than 0.6 for the whole period (1933–2014) and sub-periods both for average monthly and average maximum temperatures. LwBI values of the PIHE chronology had correlation coefficients above 0.52 (highest 0.64) with August and August-July temperatures. The PIPE BI chronologies were also positively correlated with summer temperatures, but showed lower values than PIHE with lower temporal stability. The most stable were the correlations with LwBI average August temperatures, which were above 0.52. Delta BI series displayed high correlations for the 1933–1983 period, but then decreased and this caused overall lower correlations with August temperatures. Our data shows that there is potential to develop long BI chronologies and proxy climate reconstructions from the studied species and in this way complement the knowledge of the past climate of SE Europe.

Abies spectabilis shows stable growth relations to temperature, but changing response to moisture conditions along an elevation gradient in the central Himalaya

A better understanding of growth-climate responses of high-elevation tree species across their distribution range is essential to devise an appropriate forest management and conservation strategies against adverse impacts of climate change. The present study evaluates how radial growth of Himalayan fir (Abies spectabilis D. Don) and its relation to climate varies with elevation in the Manaslu Mountain range in the central Himalaya. We developed tree-ring width chronologies of Himalayan fir from three elevational belts at the species’upper distribution limit (3750−3900 m), in the middle range (3500−3600 m), and at the lower distribution limit (3200−3300 m), and analyzed their associations with climatic factors. Tree growth of Himalayan fir varied synchronously across elevational belts, with recent growth increases observed at all elevations. Across the elevation gradient, radial growth correlated positively (negatively) with temperature (precipitation and standardized precipitation-evapotranspiration index, SPEI-03) during the summer (July to September) season. However, the importance of summer (July to September) temperatures on radial growth decreased with elevation, whereas correlations with winter (previous November to current January) temperatures increased. Correlations with spring precipitation and SPEI-03 changed from positive to negative from low to high elevations. Moving correlation analysis revealed a persistent response of tree growth to May and August temperatures. However, growth response to spring moisture availability has strongly increased in recent decades, indicating that intensified spring drought may reduce growth rates of Himalayan fir at lower elevations. Under sufficient moisture conditions, increasing summer temperature might be beneficial for fir trees growing at all elevations, while trees growing at the upper treeline will take additional benefit from winter warming.