scholarly journals About the causes of pine drying in the Belarusian Polesje

2021 ◽  
pp. 82-90
Author(s):  
Katsiaryna V. Matsiusheuskaya ◽  
Viktar N. Kisialiou ◽  
Aliaxey E. Yarotau
Keyword(s):  
Solar Radiation ◽  
21St Century ◽  
Arable Land ◽  
Climatic Conditions ◽  
Direct Solar Radiation ◽  
Limiting Factor ◽  
Natural Conditions ◽  
Pine Trees

Тhe results of identifying the causes of mass drying of pine trees in the Belarusian Polesje are presented. The object of the study is its modern generations on the former depleted sandy arable land and in natural conditions of growth. It is revealed that in the conditions of groundwater reduction after drainage reclamation in modern climatic conditions, the increase in the inflow of direct solar radiation in the 21st century was the limiting factor for the suppression of the stem productivity of pine, which led to the death of the stand.

scholarly journals The role of L/W in the solar radiation for Saharian cities

2019 ◽  
Vol 91 ◽  
pp. 05006
Author(s):  
Rami Qaoud ◽  
Alkama Djamal
Keyword(s):  
Solar Radiation ◽  
Solar Energy ◽  
Energy Levels ◽  
Direct Solar Radiation ◽  
Test Field ◽  
Natural Lighting ◽  
The Difference ◽  
The Impact ◽  
The Relationship

The urban fabric of the desert cities is based on the principle of reducing the impact of urban canyons on direct solar radiation. Here comes this research, which is based on a comparative study of the periods of direct solarisation and values of the solar energy of urban canyons via two urban fabrics that have different building densities, where the ratio between L/W is different. In order to obtain the real values of the solar energy (thermal, lighting), the test field was examined every two hours, each three consecutive days. The measurement stations are positioned by the three types of the relationship between L/W, (L≥2w, L=w, L≤0.5w). According to the results, we noticed and recorded the difference in the periods of direct solarization between the types of urban engineering canyons, reaching 6 hours a day, the difference in thermal values of air, reaching 4 °C, and the difference in periods of direct natural lighting, reaching 6 hours. It should be noted that the role of the relationship between L/W is to protect the urban canyons by reducing the impact of direct solar radiation on urban canyons, providing longer hours of shading, and reducing solar energy levels (thermal, lighting) at the urban canyons. This research is classified under the research axis (the studies of external spaces in the urban environment according to the bioclimatic approach and geographic approach). But this research aims to focus on the tracking and studying the distribution of the solar radiation - thermal radiation and lighting radiation - in different types of street canyons by comparing the study of the direct solarization periods of each type and the quantity of solar energy collected during the solarization periods.

Dynamic Modeling of Solar Radiation Disturbances Based on a Biomimetic Cloud Shading Model

2018 ◽  
Vol 140 (2) ◽  
Author(s):  
Jesús García ◽  
Iván Portnoy ◽  
Ricardo Vasquez Padilla ◽  
Marco E. Sanjuan
Keyword(s):  
Time Series ◽  
Solar Radiation ◽  
Control Strategies ◽  
Ground Level ◽  
Direct Solar Radiation ◽  
Complex Phenomenon ◽  
Two Dimensional ◽  
Multi Objective Optimization ◽  
Tuning Parameters ◽  
Radiation Time

Variation in direct solar radiation is one of the main disturbances that any solar system must handle to maintain efficiency at acceptable levels. As known, solar radiation profiles change due to earth's movements. Even though this change is not manipulable, its behavior is predictable. However, at ground level, direct solar radiation mainly varies due to the effect of clouds, which is a complex phenomenon not easily predictable. In this paper, dynamic solar radiation time series in a two-dimensional (2D) spatial domain are obtained using a biomimetic cloud-shading model. The model is tuned and compared against available measurement time series. The procedure uses an objective function based on statistical indexes that allow extracting the most important characteristics of an actual set of curves. Then, a multi-objective optimization algorithm finds the tuning parameters of the model that better fit data. The results showed that it is possible to obtain responses similar to real direct solar radiation transients using the biomimetic model, which is useful for other studies such as testing control strategies in solar thermal plants.

Projected Hydrologic Changes Under Mid-21st Century Climatic Conditions in a Sub-arctic Watershed

2014 ◽  
Vol 29 (5) ◽  
pp. 1467-1487 ◽  
Author(s):  
Debjani Deb ◽  
Jonathan Butcher ◽  
Raghavan Srinivasan
Keyword(s):  
21St Century ◽  
Climatic Conditions

THE IMPORTANCE OF AGRICULTURE FROM AREAS WITH ESPECIALLY UNFAVORABLE NATURAL CONDITIONS IN POLAND IN THE CONTEXT OF THE EUROPEAN GREEN DEAL

2021 ◽  
Vol XXIII (3) ◽  
pp. 156-168
Author(s):  
Marek Zieliński ◽  
Jolanta Sobierajewska
Keyword(s):  
Arable Land ◽  
Economic Assessment ◽  
Production Potential ◽  
Natural Conditions ◽  
Average Value ◽  
Plant Cultivation ◽  
Production Type ◽  
Production Area ◽  
Organization Of Production ◽  
Capital Value

The aim of the study is to characterize agriculture in areas (communes) with particularly unfavorable natural conditions for farming, as well as to assess the production potential, organization of production and economic situation of farms from such areas in Poland. The first part of the study describes the characteristics of agriculture in communes with particularly unfavorable natural conditions. For this purpose, data from the Institute of Soil Science and Plant Cultivation in Puławy, on the average value of the index of Valorization of Agricultural Production Area (VAPA) in communes in Poland, was used. Communes with particularly unfavorable natural conditions were those with an average VAPA index below 52 points out of 120 possible points. The organizational and economic assessment of farms according to production types was also carried out: field crops, grazing animals, and farms with mixed plant-animal production in communes with an average VAPA index lower than 52 points against a background of similar farms from other communes that have continuously kept accounting for Polish FADN in 2017-2019. It was found that communes with unfavorable natural conditions, compared to other communes, were distinguished by a smaller average utilized agricultural area (UAA) on farms, a smaller share of arable land and a greater permanent grassland in UAA, as well as e.g., a lower share of wheat and rape in total and higher total rye in the crop structure. They had, however, a greater share of land used ecologically in total UAA. They also had a higher density of livestock per 1 ha of UAA. In turn, farms from these areas – regardless of the analyzed production type, as compared to other farms, were characterized by a smaller UAA, incurred lower labor input per farm, and had a lower capital value. They also had significantly lower land and labor productivity as well as income per 1 FWU.

Analiza modului de utilizare a terenurilor în Regiunea de Dezvoltare Nord a Republicii Moldova

2020 ◽  
Author(s):  
Iurie Bejan ◽  
Keyword(s):  
Land Use ◽  
Agricultural Land ◽  
Arable Land ◽  
Current Mode ◽  
Climatic Conditions ◽  
Development Region ◽  
Agro Forestry

The land use has undergone some changes in the last 30 years, by reducing the areas with arable land, converting multi-annual plantations into other categories of land, etc. According to the current mode of land use, the Northern Development Region has a pronounced agricultural profile - 80.3% of the total area represents agricultural land. The spatial differentiations regarding the morphological and agro-climatic conditions allowed the identification within the region of areas with agro-forestry and agro-pastoral specializations.

scholarly journals The Potential of Solar Air Heating in the Turkish Industrial Sector

2018 ◽  
Vol 63 (1) ◽  
pp. 57-66
Author(s):  
Balázs Bokor ◽  
Hacer Akhan ◽  
Dogan Eryener ◽  
László Kajtár
Keyword(s):  
Solar Radiation ◽  
Energy Savings ◽  
Measurement Data ◽  
Industrial Sector ◽  
Climatic Conditions ◽  
Cold Climate ◽  
Conventional Heating ◽  
Industrial Building ◽  
High Solar Radiation ◽  
Mathematical Correlation

Transpired solar collector (TSC) systems are simple solutions for the preheating of ventilation air with solar energy. Their performance is a function of several environmental factors, so the climatic conditions of the location play an important role. In this paper, the effect of different climatic zones on the thermal performance of the TSC is investigated. To exclude other sources of influence, the same reference industrial building is examined in four Turkish locations (Antalya, Istanbul, Ankara and Sivas) representing different climatic conditions. RETScreen simulation is carried out for all four regions to obtain the drop of conventional heating requirement in case absorber azimuth of 0°, 45° and 90°. To illustrate the performance, temperature rise, heating energy savings and annual solar fraction are presented. Generally, it can be stated that a location with cold climate and high solar radiation at the same time benefits most from the use of a TSC system. A mathematical correlation has been found showing the solar fraction's dependence on solar radiation and heating degree days. Finally, simulation results have been compared to a set of measurement data from an industrial building's TSC system near Istanbul.

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