Phenology of Coffea canephora from different maturation cycles

As Germany accelerates its renewable energy transition aiming for 80% renewable electricity by 2030, the expansion of wind and solar capacity, the phase-out of fossil fuels, and improvements to grid infrastructure are crucial for ensuring a sustainable and secure energy system. In this context, seasonal forecasts of wind and solar radiation have the potential to support energy reserve management, planning for variable renewable supply, and improving the long-term resilience of the energy system. This study focuses on the development and evaluation of seasonal forecasts for 100m wind speed and solar radiation across Germany. We apply the statistical-dynamical downscaling method EPISODES (Kreienkamp et al., 2019) to hindcast data (1990–2020) from the German Climate Forecasting System Version 2.1 and investigate the predictability and forecast skill of 100m wind speed and solar radiation forecasts on lead times ranging from one to six months. The analysis focuses on the summer season, when solar energy production is highest, and the winter season, when wind energy production peaks. Despite the overall rather low forecast skill of seasonal forecasts for Germany, we find that skillful wind forecasts for the winter season are possible with a reasonable correlation to observations. Furthermore, the forecast model is able to predict solar radiation in summer over southern Germany, a region that contains most of the solar plants in Germany, relatively well. We further employ a statistically selected subsampling approach (Dalelane et al., 2020 and Dalelane et al. 2025, in preparation) to generate a smaller ensemble based on large-scale teleconnections in the North Atlantic and apply it to the forecasts. With this approach, we find a substantial increase in forecast skill for both wind and solar radiation in both summer and winter compared to the full ensemble. Our findings show that skillful seasonal forecasts in winter and summer are possible despite the limitations and challenges of seasonal prediction. In the future, we plan to use multi-model approaches and teleconnection indices to further explore potentials for more skillful seasonal prediction of wind and solar radiation and publish skillful forecasts on the DWD climate prediction webpage (http://www.dwd.de/climatepredictions). This user-oriented website consistently evaluates and displays subseasonal, seasonal and decadal climate predictions at high resolution for Germany.Kreienkamp, F., Paxian, A., Früh, B., Lorenz, P., & Matulla, C. (2019). Evaluation of the empirical–statistical downscaling method EPISODES. Climate dynamics, 52, 991-1026.Dalelane, C., Dobrynin, M., & Fröhlich, K. (2020). Seasonal forecasts of winter temperature improved by higher‐order modes of mean sea level pressure variability in the North Atlantic sector. Geophysical Research Letters, 47(16), e2020GL088717.

Effect of progressive irrigation water reductions on super-high-density olive orchards according to different scarcity scenarios

Thermal and moisture characteristics of the bamboo structure wall were tested in natural climate and three representative variation processes of heat and moisture: heating from solar radiation in summer at normal temperature and humidity, heating from solar radiation in summer at normal temperature and high humidity after rain, humidifying from brash in summer at high temperature and normal humidity. The results show that, in summer, the largest temperature difference between external and internal surface of the 28 mm-thick bamboo plywood wall is 11.73 °C (at 15:40) and the largest strain difference is 136 μm/m (at 18:50), both in ambient and indoor conditioned environment. In heating process, lengthways of the wall surface are in contracting strain while transverse ways are in expanding strain at initial stage and in contracting strain during later period. When the high temperature wall is humidified by rain, the surface temperature drops, moisture content increases and the expanding strain is presented on the surface during the whole process. Temperature and moisture content are two important factors which affect thermal and moisture stress (TMS) of the bamboo structure wall. The TMS is not only related to temperature and moisture content, but also greatly affected by temperature gradient, moisture content gradient and rates of changing.

Simple SummaryThis study of the phytoplankton community in the Adriatic Sea shows increasing species diversity over a 14-year period despite the effects of climate change in terms of increased sea surface temperature and increasing solar radiation in summer. Fluctuations in the dynamics of the different phytoplankton groups were observed in the studied area. The dominant groups were diatoms and phytoflagellates, but their proportions varied depending on the proximity to the coast as shown by the distribution of chlorophyll a.Considering the role of phytoplankton in the functioning and health of marine systems, it is important to characterize its responses to a changing environment. The central Adriatic Sea, as a generally oligotrophic area, is a suitable environment to distinguish between regular fluctuations in phytoplankton and those caused by anthropogenic or climatic influences. This study provides a long-term perspective of phytoplankton assemblage in the central eastern Adriatic Sea, with 14 years of continuous time series data collected at two coastal and two offshore stations. The predominant phytoplankton groups were diatoms and phytoflagellates, but their proportion varied depending on the vicinity of the coast, as evidenced also by the distribution of chlorophyll a. In the coastal environment, the phytoplankton biomass was substantially higher, with a higher proportion of microphytoplankton, while small phytoplankton accounted for the majority of biomass in the offshore area. In addition, a decreasing trend in diatom abundance was observed in the coastal waters, while such trend was not so evident in the offshore area. Using a neural gas algorithm, five clusters were defined based on the contribution of the major groups. The observed increase in diversity, especially in dinoflagellates, which outnumber diatom taxa, could be a possible adaptation of dinoflagellates to the increased natural solar radiation in summer and the increased sea surface temperature.

The inter-annual and inter-decadal variation of temperature in Dabie Mountain of West Anhui Province is analyzed according to actually measured data of daily average temperature, maximum temperature and minimum temperature during 1960-2013 in five meteorological stations in Dabie Mountain. Results show: The quarterly and annual average temperature, average maximum temperature and average minimum temperature (except the average maximum temperature in summer) in Dabie Mountain of West Anhui Province are all in a rising tendency. The annual average temperature increases remarkably at an amplitude of 0.165°C/10 years. The increase amplitude of average minimum temperature is 1-2 times of the average maximum temperature, and the daily range shows obvious reduction. The annual extremely maximum temperature and extremely minimum temperature are both on the rise, and the amplitude of the latter is larger than that of the former. From 1960s, the average temperature, average maximum temperature and average minimum temperature turned rising in Dabie Mountain of West Anhui Province. The abnormally warm years are 1967, 1968, 206, 207, 1998 and 2013, while the abnormally cold years are 1967 and 1981.

Descriptions of structure and flowering phenology of the tropical tree species Cedrela mexicana, Cordia glabra, Erythrina poeppigiana. Tabebuia rosea, and Tabebuia ochrea ssp. neochrysantha are used to analyze and illustrate the complex relations between structure, vegetative development, and flowering in tropical trees. Because of the strong positional differentiation within tree crowns and the repetition of vegetative and reproductive growth cycles in trees, flower development and its control are more complex than in herbaceous plants. Formation of terminal inflorescences, as found in Cedrela, Cordia, and Tabebuja, regularly occurs at the end of a flush of determinate shoot growth; flower initation, like shoot growth cessation, is therefore controlled by internal, correlative factors rather than by environmental changes. Initiation of lateral inflorescences is usually preceded by growth cessation in the indeterminate, vegetative shoot, but the timing and control of flower induction in lateral buds are unknown. For many tropical trees, particularly those growing in seasonal climates, flower development is discontinuous, i.e., flower initiation and anthesis are separated by a prolonged rest period and must be controlled separately. Delayed anthesis is usually triggered by rehydration of previously water-stressed trees resulting from leaf shedding or, in dry habitats, by rainfall. Because of different degrees of seasonal water stress, leaf fall and subsequent anthesis in several species extend over three to four months. The observed periodicity of anthesis in tropical trees is thus largely determined by seasonal changes in tree water status and is unlikely to be the result of selection for optimum tree-pollinator interaction. IN MOST TROPICAL TREES, flowering, like vegetative growth is episodic, and seasonal peaks of flowering have been recorded for many tropical forests (e.g., Fournier and Salas 1966, Janzen 1967). During recent years, tropical ecologists have considered the temporal pattern of flowering the result of coevolution of trees with pollinators and seed predators. It has been argued that peaks of flowering occur during periods of high pollinator activity, and that overlapping, but different, flowering periods in related species reduce competition for pollinators and assure a continuous source of nectar to pollinators (Janzen 1967, Gentry 1976, Stiles 1978). If the temporal pattern of flowering is adaptive, then mechanisms for the specific timing of flowering must have evolved in tropical trees. The timing of flowering in tropical trees usually has been ascribed to environmental control mechanisms analogous to those that have evolved in temperate plants to adapt vegetative and reproductive development to a growing season of limited duration (Larcher 1980). Relations between tree architecture, vegetative growth and flowering of tropical trees have been rarely considered. In this paper, I shall use descriptions of the flowering behavior of five tropical tree species as a basis for discussing the relations between tree architecture, vegetative development, and flowering, as well as our scant knowledge of their internal and environmental controls. I will show that evolution of the temporal pattern of flowering in tropical trees cannot be adequately explained as resulting from biotic interactions alone, but must be seen in the context of overall tree development as determined by a given set of climatic, edaphic, and biotic factors. STUDY SITES AND METHODS Most of the phenological observations on flowering of tropical trees discussed in this paper were made on the Pacific slope of Costa Rica, Central America, along an altitudinal gradient extending from the deciduous lowland forest of Guanacaste Province (Janzen 1967, Daubenmire 1972, Frankie et al. 1974, Opler et al. 1976, Reich and Borchert 1982, 1984) through the lower montane forest at Villa Col6n (800 m altitude) and Santa Ana (900 m; Fournier and Salas 1966, Fournier 1969) to the Central Valley of Costa Rica (La Sabana, 1100 m; San Pedro Montes de Oca, 1200 m; Granadilla, 1350 m) (Fournier 1969, Borchert 1980). The climate in the entire area is characterized by a dry season lasting from late November to April/May and a wet season providing adequate rainfall (approx. 2000 mm) for the remainder of the year. With increasing altitude, the severity of the dry season diminishes and some species change from a deciduous to an evergreen habit (e.g., Erythrina poeppigiana, Tabebuia rosea; Fournier 1969, Borchert 1980). The discussion of tree morphology is based on the analysis of tropical tree architecture by Hall6 et al. 1978, where definitions of all morphological terms can be found. MORPHOLOGY AND PHENOLOGY OF FLOWERING IN FIVE TROPICAL TREE SPECIES TABEBUIA ROSEA (BERTOL.) DC, BIGNONIACEAE.-The shoot system of T. rosea is composed of many orthotropic, symBIOTROPICA 15(2): 81-89 1983 81 This content downloaded from 157.55.39.17 on Fri, 02 Sep 2016 06:06:02 UTC All use subject to http://about.jstor.org/terms

Mango trees have no distinct phenology: The case of mangoes in the tropics

This study aims at understanding the relationship between climatic factors and its impact on sugarcane productivity in Karnataka. To understand the above objective we estimated the factors that affect sugarcane productivity. After appropriate statistical analysis, the strength of empirical results was checked through fixed effects panel regression model and Prais–Winsten model with panel corrected standard errors models. The data point has 592 observations corresponding to 16 districts of Karnataka, selected on the basis of the agro-climatic region to which they belong, with panel data for a period of 1966–2002. Since our prime interest was sugarcane productivity it was entered as a dependent variable in the models. Average rainfall, average maximum and average minimum temperature, area under irrigation and consumption of fertilizers are considered as explanatory variables. In order to capture the variability in the climatic factors it was decomposed into four seasons, viz., monsoon, summer, autumn and winter. The results conclude that though the average rainfall in different seasons has a direct positive impact, the rainfall in summer is significantly affecting sugarcane yield. The climatic variables of average minimum and maximum temperatures in different seasons have varied impacts on the yield of sugarcane. The maximum temperature in summer and the minimum temperatures in monsoon, winter and autumn have a significant positive impact on the sugarcane yield in Karnataka, whereas maximum temperature in autumn and minimum temperature in summer has negative relationship. The study suggests that adaptation strategies need special attention on technologies and management regimes that will enhance sugarcane tolerance to fluctuating temperatures.

Grassland located in the arid and semi-arid ecosystems has an evident ecological fragility and is easily vulnerable to climatic variations. Although several studies have shown the close relationship between net primary production (NPP) and seasonal or annual climate changes, it is currently unclear that whether such response in semi-arid regions is associated with grassland types that have different physiological characteristics, especially in the grassland ecosystem of Inner Mongolia that spans meadow-typical-desert steppe. This study used NPP estimated by Carnegie–Ames Stanford Approach (CASA) model, and focused on grassland type-dependent spatiotemporal changes of NPP and its response to climate factors on annual and seasonal scales. The results showed that the NPP simulated by the CASA model was in good agreement with the ground-observed NPP (R2 = 0.62, P < 0.001), and the RMSE value was 22.91 gC ∙ m−2. From 2001 to 2018, grassland NPP increased marginally with the increment of 0.89gC ∙ m−2 ∙ yr−1, the average NPP was 341.55gC ∙ m−2 ∙ yr−1, and there was a gradual decline from northeast to southwest. On the annual scale, grassland NPP had the strongest positive correlation with precipitation, followed by solar radiation and a negative correlation with temperature. On the seasonal scale, precipitation still had the greatest impact on NPP. In spring, grassland and solar radiation were positively correlated, but in summer and autumn, there was no significant correlation. In autumn, grassland had a positive correlation with temperature, while in spring and summer, there showed a negative correlation. For different grassland types, precipitation was the most important factor that influencing temperate typical steppe and temperate salted meadow in spring and summer, while solar radiation had the strongest effect on temperate desert steppe and temperate meadow. Temperate meadow steppe and temperate swamp meadow were most affected by precipitation in spring, while they were most affected by solar radiation in summer.

&amp;lt;p&amp;gt;Japan has plenty of diaries in the 17th to 19th centuries, which include records of daily weather conditions (&amp;quot;fine&amp;quot;, &amp;quot;cloudy&amp;quot;, &amp;quot;rainy&amp;quot;, etc.) It is well known that they have been used for reconstructing climate variation and events, although it provided qualitative data, not instrumental observations.&amp;lt;/p&amp;gt;&amp;lt;p&amp;gt;We estimate global solar radiation from weather conditions. Global solar radiation is an important factor for the energy balance of the Earth, and is also fundamental to the hydrological cycle and agricultural productivity. Our method is effective for all seasons and which could produce reconstruction with higher temporal resolution than other proxy data, for example tree rings.&amp;lt;/p&amp;gt;&amp;lt;p&amp;gt;Weather descriptions are classified into 3 categories and weather categories convert to solar radiation. The parameters of conversion are calculated by using JMA observations from 1995 to 1999.&amp;lt;/p&amp;gt;&amp;lt;p&amp;gt;We reconstructed monthly mean global solar radiation from 1821 to 1850 based on the weather records described in 11 historical diary documents. We focused on the years of Tempo Famine from 1833 to 1839.&amp;lt;/p&amp;gt;&amp;lt;p&amp;gt;In 1836, monthly solar radiation in summer in the east-west zone of Japan including Kanto, Kinki, and northern Kyushu was smaller than the provisional normal (average of 1821-1850). It was 10% or more smaller than the normal in July and August. However, it was not particularly small in Tohoku to the north of the zone and in southern Kyushu to the south of the zone. The characteristic of reconstruction in 1836 is that lower solar radiation prolonged from May to September in the central area of Japan. This suggests that climatic condition similar to Baiu was prolonged, and that it was cold in Tohoku. On the other hand, in 1833 and 1838, when famines also occurred, the reconstructed solar radiation was low in Tohoku.&amp;lt;/p&amp;gt;&amp;lt;p&amp;gt;We also checked the effect on market economy by observing the daily price of rice, the main crop at that time. For 1836, we can observe the sharp rise of the price in July. It suggests that the market had reacted to the bad climate condition before the harvest season. After this sharp rise, four times higher than usual, rice price reached a plateau then fell in September 1837.&amp;lt;/p&amp;gt;&amp;lt;p&amp;gt;While the rice price in 1833 and 1838 also rose up in summer, they were only two or three times higher than usual and, more importantly, they quickly bounced back.&amp;lt;/p&amp;gt;&amp;lt;p&amp;gt;Cross check between the reconstructed solar radiation and the rice price data support thus enables us to conclude that there existed a big difference even among the years recorded as &amp;amp;#8220;famine years&amp;amp;#8221; on the historical documents.&amp;lt;/p&amp;gt;

Disentangling the response of vegetation dynamics to natural and anthropogenic drivers over the Qinghai-Tibet Plateau using dimensionality reduction and structural equation model

In recent times and across the globe, the concept of climate has gained much relevance because of its dynamic and complex nature and the significant influence it has on various aspects of the environment, including the increasing threat of global climate change. This study focuses on the assessment of climatic variation in Ilorin based on the variations in rainfall and temperature within the period 1980-2015. Time Series Analysis was used to determine the trend of rainfall and temperature within the period 1980-2015. The 5-Year Moving Average was used to smoothen the time series and to eliminate unwanted fluctuations. Linear Regression was used to estimate the value of variable Y (total rainfall or average minimum temperature), corresponding to a given value of variable X (time), while MAKESEN software was used to determine the temporal trend of rainfall indices within the study period. Furthermore, the study focused on the spatial variations of total rainfall and average minimum temperature in the study area. The result revealed that there is downward trend of 0.814 mm per year in the annual mean rainfall and also there is an upward trend of 0.029 per year in average annual minimum temperature and total annual maximum temperature has an upward trend of 0.01 mm per year. Thus, the rainfall is decreasing and temperature tends to increase. Key word: Climate variability, Rainfall, Temperature, Period, Temporal trend, Kwara state

The present research was conducted during 2012 in order to determine the essential oil content and composition of Echinophora tenuifolia subsp. sibthorpiana Tutin. Plants were collected during rosette, vegetative growth, full flowering and fruit-ripening stages. Oil was extracted using Clavenger hydro-distillation apparatus from either fresh, shade dried or sun dried samples. Oil composition was determined with a GC/MS. Oil content of samples showed significant variation during the vegetative stages of development. Oil contents of fresh samples were found to be 0.76% at seedling stage whereas oil content has risen to 1.06% at seed set. The shade-dried samples had higher oil contents than the fresh and sun dried samples. The oil composition of pickling herb changed with drying method and growth stage. Throughout the growth stage of the plant, the oil was composed of 21 components and the main components were found to be α- phellandrene (47.43 - 66.39%) and methyl eugenol (21.29 – 38.72%). While methyl eugenol content decreased during vegetation period for both fresh and dried samples, α-phellandrene level increased. Attention should be given to the collection time and drying method of pickling herb for different uses since vegetative stage and drying method influence oil content and composition.

Influence of Low Air Temperature and Insufficient Solar Radiation in Summer of 2015 on Yield of Paddy Rice in Soma, Fukushima Prefecture

No abstract available