Acorn production by oaks in central coastal California: influence of weather at three levels

1996 ◽  
Vol 26 (9) ◽  
pp. 1677-1683 ◽  
Author(s):  
Walter D. Koenig ◽  
Johannes M.H. Knops ◽  
William J. Carmen ◽  
Mark T. Stanback ◽  
Ronald L. Mumme

Mean annual acorn crop size of oaks in central coastal California correlated with weather for four of five species. For the deciduous Quercuslobata and Quercusdouglasii, larger crops were produced in years when April temperatures were warmest, while for the evergreen Quercusagrifalia and Quercuschrysolepis, crops were larger when there was more rain one and two years prior to the year when acorns were produced. No correlations were found between weather and mean annual acorn production by Quercuskelloggii. Within years, individual Q. douglasii that flowered during periods of greater solar radiation produced more acorns, and during 1 of 5 years individual Q. lobata and Q. agrifolia produced larger crops when they flowered during warm, dry periods. These results indicate that conditions favorable for pollination and fertilization strongly enhance mean annual acorn production in Q. lobata and Q. douglasii and may have an effect on differences in acorn crop size among individual Q. lobata, Q. douglasii, and Q. agrifolia. Mean annual acorn crops of these three species were significantly concordant among three sites in central coastal California 300 km apart. Weather conditions were also significantly correlated, especially annual rainfall and mean April temperatures. Thus, the environmental factors that have the strongest influence on mean annual acorn production within a site are also those that are the most geographically concordant. However, we found no relationship between environmental factors and differences in mean annual acorn production by these same three species at the three sites.

PLoS ONE ◽  
2021 ◽  
Vol 16 (9) ◽  
pp. e0257882
Author(s):  
Stephanie L. Shaw ◽  
Kathryn M. Renik ◽  
Greg G. Sass

Angler trip success and catch rates are dependent upon a fishes’ vulnerability to angling. Angling vulnerability can be influenced by angler-specific attributes (i.e., bait choice, lure size, use of a guide), and individual fish traits (i.e., boldness, aggression, stress responsiveness, and memory retention). The mechanisms that function in a fishes’ angling vulnerability, and contribute to catch rate, are likely correlated with environmental factors however, the influence of environmental factors on angling vulnerability are not well understood. We used the long-term (1946 –present) compulsory creel dataset from Escanaba Lake, WI, USA to test for interactions between angling vulnerability (i.e., angler trip success and catch rates) and environmental factors to better understand these dynamics in recreational fisheries. Our objective was to test for the influence of angler associated variables and environmental factors on open water angler trip success (i.e., catch ≥ one fish) and catch rate of walleye Sander vitreus and muskellunge Esox masquinongy during 2003–2015 using a hurdle model approach. Fishing trip success and catch rates for both species were most strongly influenced by angler-related variables (i.e., guide status, bait type, the proportion of the fish population previously caught). Environmental factors associated with lower light intensity (i.e., diel period, mean daily solar radiation, solar-Julian day interaction) had a positive influence on walleye vulnerability. Lower air temperatures and lunar position (moon overhead or underfoot) and phase (gibbous’ and full moon) also had a positive effect on walleye angling. Muskellunge trip success and catch rate were positively influenced by light metrics (i.e., diel period and mean daily solar radiation) and increased with air temperature. Lunar variables (position and phase), as well as wind speed and direction also influenced muskellunge angling vulnerability. A better understanding of the influence of environmental factors on angling vulnerability is an important component of fisheries management as management goals focus on balancing fish populations and creating satisfactory catch rates to enhance the angling experience. Our results suggest that angler-specific variables, light, temperature, lunar, and weather conditions influenced species-specific angling vulnerability for walleye and muskellunge.


2018 ◽  
Vol 1 (3) ◽  
Author(s):  
IJE Manager

In the past century, fossil fuels have dominated energy supply in Indonesia. However, concerns over emissions are likely to change the future energy supply. As people become more conscious of environmental issues, alternatives for energy are sought to reduce the environmental impacts. These include renewable energy (RE) sources such as solar photovoltaic (PV) systems. However, most RE sources like solar PV are not available continuously since they depend on weather conditions, in addition to geographical location. Bali has a stable and long sunny day with 12 hours of daylight throughout the year and an average insolation of 5.3 kWh/m2 per day. This study looks at the potential for on-grid solar PV to decarbonize energy in Bali. A site selection methodology using GIS is applied to measure solar PV potential. Firstly, the study investigates the boundaries related to environmental acceptability and economic objectives for land use in Bali. Secondly, the potential of solar energy is estimated by defining the suitable areas, given the technical assumptions of solar PV. Finally, the study extends the analysis to calculate the reduction in emissions when the calculated potential is installed. Some technical factors, such as tilting solar, and intermittency throughout the day, are outside the scope of this study. Based on this model, Bali has an annual electricity potential for 32-53 TWh from solar PV using amorphous thin-film silicon as the cheapest option. This potential amount to three times the electricity supply for the island in 2024 which is estimated at 10 TWh. Bali has an excessive potential to support its own electricity demand with renewables, however, some limitations exist with some trade-offs to realize the idea. These results aim to build a developmental vision of solar PV systems in Bali based on available land and the region’s irradiation.


2021 ◽  
Vol 7 (1) ◽  
Author(s):  
K. Pugh ◽  
M. M. Stack

AbstractErosion rates of wind turbine blades are not constant, and they depend on many external factors including meteorological differences relating to global weather patterns. In order to track the degradation of the turbine blades, it is important to analyse the distribution and change in weather conditions across the country. This case study addresses rainfall in Western Europe using the UK and Ireland data to create a relationship between the erosion rate of wind turbine blades and rainfall for both countries. In order to match the appropriate erosion data to the meteorological data, 2 months of the annual rainfall were chosen, and the differences were analysed. The month of highest rain, January and month of least rain, May were selected for the study. The two variables were then combined with other data including hailstorm events and locations of wind turbine farms to create a general overview of erosion with relation to wind turbine blades.


2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Abolfazl Mohammadbeigi ◽  
Salman Khazaei ◽  
Hamidreza Heidari ◽  
Azadeh Asgarian ◽  
Shahram Arsangjang ◽  
...  

AbstractObjectivesLeishmaniasis is a neglected and widespread parasitic disease that can lead to serious health problems. The current review study aimed to synthesize the relationship between ecologic and environmental factors (e.g., weather conditions, climatology, temperature and topology) and the incidence of cutaneous leishmaniasis (CL) in the Old World.ContentA systematic review was conducted based on English, and Persian articles published from 2015 to 2020 in PubMed/Medline, Science Direct, Web of Science and Google Scholar. Keywords used to search articles were leishmaniasis, environmental factors, weather condition, soil, temperature, land cover, ecologic* and topogr*. All articles were selected and assessed for eligibility according to the titles or abstracts. The quality screening process of articles was carried out by two independent authors. The selected articles were checked according to the inclusion and exclusion criteria.Summary and outlookA total of 827 relevant records in 2015–2020 were searched and after evaluating the articles, 23 articles met the eligibility criteria; finally, 14 full-text articles were included in the systematic review. Two different categories of ecologic/environmental factors (weather conditions, temperature, rainfall/precipitation and humidity) and land characteristics (land cover, slope, elevation and altitude, earthquake and cattle sheds) were the most important factors associated with CL incidence.ConclusionsTemperature and rainfall play an important role in the seasonal cycle of CL as many CL cases occurred in arid and semiarid areas in the Old World. Moreover, given the findings of this study regarding the effect of weather conditions on CL, it can be concluded that designing an early warning system is necessary to predict the incidence of CL based on different weather conditions.


Author(s):  
Jhon Charles Donato Rondón ◽  
Yaira Ayarith Abuhatab Aragón

This study assessed short-term succession and related changes in diversity and succession of benthic diatom assemblages in a tropical rainforest stream in the biogeographic region of Chocó, Colombia. Diatom colonization in situ was studied over a 60-day period, in which we analyzed the number of valves and the taxonomic changes. The Shannon index ranged from 2.06 to 3.02 bits. A total of 127 species were identified and the most abundant were acidophilic species such as Eunotia intermedia, E. veneris, E. bilunaris var. mucophila, E. pirla and E. bilunaris. A Detrended Canonical Correspondence Analysis (DCCA) was used to explore the succession of diatom assemblages and its driving environmental factors. The DCCA explained 74.1% of the correlation between environmental variables and diatom species and 16.2% of the data variance. The species fell into four groups, the first group (Eunotia incisa, Frustulia saxonica, Fragilaria capucina var. acatu, among others) was related to lower nitrate concentrations, acidic pH and lower water temperature. The second group (Fragilaria capensis, Gomphonema olivaceum, Cymbella gracilis, among others) was associated to higher alkalinity and lower solar radiation availability. The third group (Nitzschia obtusa, N. amphibia, Naviculadicta vitabunda, Navicula cryptocephala, among others) was related to lower phosphate, higher nitrate concentrations, lower pH, and higher temperatures. The fourth group (Eunotia soleirolli, Frustulia vulgaris and F. rhomboides) was associated with higher solar radiation and lower alkalinity. These results underscore the importance of diatom diversity in Neotropical streams and the relevance of small variations in environmental factors on the composition of reference assemblages of Neotropical fluvial systems.


PLoS ONE ◽  
2020 ◽  
Vol 15 (11) ◽  
pp. e0241794
Author(s):  
Maroua Jerbi ◽  
Sonia Labidi ◽  
Anissa Lounès-Hadj Sahraoui ◽  
Hatem Chaar ◽  
Faysal Ben Jeddi

Whereas the role of arbuscular mycorrhizal fungi (AMF) in plant growth improvement has been well described in agroecosystems, little is known about the effect of environmental factors on AMF root colonization status of barley, the fourth most important cereal crop all over the world. In order to understand the influence of environmental factors, such as climatic and soil physico-chemical properties, on the spontaneous mycorrhizal ability of barley (Hordeum vulgare L.), a field investigation was conducted in 31 different sites in sub-humid, upper and middle semi-arid areas of Northern Tunisia. Mycorrhizal root colonization of H. vulgare varied considerably among sites. Principal component analysis showed that barley mycorrhization is influenced by both climatic and edaphic factors. A partial least square structural equation modelling (PLS-SEM) revealed that 39% (R²) of the total variation in AMF mycorrhizal rate of barley roots was mainly explained by chemical soil properties and climatic characteristics. Whereas barley root mycorrhizal rates were inversely correlated with soil organic nitrogen (ON), available phosphorus amounts (P), altitude (Z), average annual rainfall (AAR), they were directly correlated with soil pH and temperature. Our results indicated that AMF root colonization of barley was strongly related to climatic characteristics than chemical soil properties. The current study highlights the importance of the PLS-SEM to understand the interactions between climate, soil properties and AMF symbiosis of barley in field conditions.


1962 ◽  
Vol 10 (4) ◽  
pp. 247-253
Author(s):  
G. Stanhill

DM production from a heavily fertilized lucerne crop grown at Gilat and irrigated daily was compared with potential photosynthesis calculated from meteorological data [see F.C.A. 12: 1940]. After corrections were applied for losses due to respiration, root growth and light wasted beneath the crop canopy, calculated amounts agreed well with those measured. The percentage of light utilized was 33% with cutting at 31-day intervals and 46% with cutting at 48-day intervals. DM production was correlated positively with solar radiation and negatively with air temperature.-R.B. (Abstract retrieved from CAB Abstracts by CABI’s permission)


Author(s):  
Yu. O. Tararico ◽  
Yu. V. Soroka ◽  
R. V. Saidak

Relevance of research. Due to ongoing climate change, almost the entire territory of the Steppe of Ukraine by annual humidity factor belongs to the dry and very dry zones, the relative area of ​​which has increased by 13.2% of the total area of ​​the country compared to the 1960-1990s. At the same time, for today in Ukraine only about 500 thousand hectares are actually irrigated, that is 19% of the potential area. Purpose of research. To determine the patterns and trends of climate change in the western part of the dry Steppe of Ukraine and analyze the economic indicators of production activity in the region as to the variable weather conditions. Research methodology. Climate change was estimated on the basis of Climate Water Balance (CWB) and Hydrothermal Coefficient (HTC) values. The analysis of the economic efficiency of agricultural production was carried out by analyzing the statistical data for Odessa region and for the chosen agricultural enterprise. Research results and conclusions. The use of significant heat supply in the dry Steppe zone is limited by insufficient water supply conditions. In the years of 1991-2016  the average annual rainfall was 480 mm and since the early 2000s there has been a slight increase in that. However, even having 500-550 mm of average annual rainfall that has been observed over the past five years, it is not enough for providing high-yield agricultural production. High thermal regime couses high evaporation that in turn, leads to water supply deficit, which at the end of the growing season amounts to 336-436 mm. According to the HTC index in the region 80% of cases show severe and moderately arid vegetation conditions. At the same time, irrigation area in the region has decreased to a minimum, which has led to the domination of winter cereals and sunflower in the cropping system. Under variable weather conditions, winter wheat yields ranged from 19.4 to 38.5 c/ ha (31.4 c/ha on average) and sunflower - from 12.2 to 21.4 c/ha (17.4 c/ha on average), winter rape - from 13.1 to 20.9 c/ha (18.2 c/ha). It was proved a close direct relationship between the sale price of products of all studied crops and their cost price, as well as the inverse relationship of these indicators with the crop yield. The profitability of winter wheat from 2011 till 2016 ranged from 17 to 153 USD/ha with an average value of 86 USD/ha, winter rape - from 39 to 273 USD/ha with an average value of 166 USD  ha and sunflower - from 116 to 315 USD/ha with an average value of 192 USD/ha. Corn and soybeans have proven to be unprofitable in some years, which obviously explains rather small areas under these crops in the region. Above mentioned demonstrates the high economic instability of agricultural production in changing weather conditions, which is accompanied by significant risks for producers, especially when attracting credits. This situation, in turn, leads to a limited use of intensification means, in particular mineral fertilizers, which promotes agrochemical soil degradation. Under unstable water supply, the magnitude of net profit variation per hectare of arable land in Odessa region is 33-188 USD/ha (111 USD/ha on average). It is possible to increase these indicators by increasing the share of winter rape in the cropping system. With the optimization of the water and air soil regimes as well as crop rotation factor, the profitability of agricultural production in the region can be increased up to 580-600 USD/ha. Similar results were obtained after analyzing the statistical data from the southern regions within the dry steppe zone.


PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e12373
Author(s):  
Lili Jin ◽  
Sasa Zhou ◽  
Qing He ◽  
Alim Abbas

The characteristics of solar radiation and the influence of sand and dust on solar radiation in the northern margin of Taklimakan Desert were analyzed using radiation observation data from 2018. The results showed that the annual total radiation, direct radiation, and scattered radiation at Xiaotang were 5,781.8, 2,337.9, and 3,323.8 MJ m−2, respectively. The maximum monthly total radiation, direct radiation, and scattered radiation were observed in July (679.8 MJ m−2), August (317.3 MJ m−2), and May (455.7 MJ m−2), respectively. The aerosol optical depth corresponded well with the scattered radiation, and the maximum value was in May. Further analysis showed a significant correlation between the total radiation and solar height angle under different weather conditions. Under the same solar height angle, total radiation was higher during clear days but lower on sandstorm days. Calculation of atmospheric transmittance showed that the average atmospheric transmittance on a clear day was 0.67; on sand-and-dust days, it was 0.46. When the atmospheric transmittance was 0.5, the increase in scattering radiation by aerosol in the air began to decrease. Probability analysis of radiation indicated the following probabilities of total radiation <500 W m−2 occurring on clear, floating-dust, blowing-sand, and sandstorm days: 67.1%, 76.3%, 76.1%, and 91.8%, respectively. Dust had the greatest influence on direct radiation; the probabilities of direct radiation <200 W m−2occurring on clear, floating-dust, blowing-sand, and sandstorm days were 44.5%, 93.5%, 91.3%, and 100%, respectively, whereas those of scattered radiation <600 W m−2were 100%, 99.1%, 98.1%, and 100%, respectively. Therefore, the presence of dust in the air will reduce scattered radiation.


Formulation of the problem. Understanding that solar energy is the main source of the majority of biological, chemical and physical processes on Earth, investigation of its influence on different climatic fields allows us to define the features of its space and hour fluctuations. To define radiation and temperature regime of the territory it is necessary to determine climatic features of the spreading surface, which absorbs and will transform solar energy. Considering the fact that modern climatic changes and their consequences cover all components of the system, today there is a problem of their further study for comprehension of atmospheric processes, modeling weather conditions on different territories depending on the properties. The purpose of the article is to determine interrelations between indexes of solar radiation (the Wolf's number) and air temperature, atmospheric pressure on the territory of Ukraine during 1965-2015, their change in space and time. Methods. Correlative method is one of the main methods of a statistical analysis which allows us to receive correlation coefficients of solar radiation variability indexes, air temperature, atmospheric pressure on the territory of the research. This technique estimates the extent of solar radiation influence on temperature regime of the territory and distribution of atmospheric pressure. Results. Coefficients of correlation, which characterize variability of solar radiation indexes, air temperature and atmospheric pressure on the explored territory have been received by means of statistical correlation analysis method. This technique allows us to estimate the degree and nature of solar radiation influence on a temperature regime of the territory and distribution of atmospheric pressure. It has been defined that direct correlative connection between indexes of solar radiation is characteristic of air temperature and atmospheric pressure fields. Significant statistical dependence between incoming solar radiation on the territory of Ukraine and atmospheric pressure has been noted during the spring and autumn periods mainly at the majority of stations. Between indexes of solar radiation and air temperature the inverse correlative connection in winter will be transformed to a direct connection during the spring and summer periods. Scientific novelty and practical significance. Physical processes, which happen in the atmosphere, are characterized by complex interrelations. For further research it is important to define solar radiation value and the extent of influence on climatic conditions.


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