scholarly journals EFFECT OF SOLAR RADIATION INTENSITY ON THE VEGETATIVE GROWTH AND YIELD OF COFFEE

1969 ◽  
Vol 26 (4) ◽  
pp. 73-90
Author(s):  
J. Guiscafré Arrillaga ◽  
Luis A. Gómez
Keyword(s):  
Soil Moisture ◽  
Relative Humidity ◽  
Solar Radiation ◽  
Ecological Factors ◽  
The Other ◽  
Growth And Yield ◽  
Full Sunlight ◽  
Solar Radiation Intensity ◽  
Yearly Average ◽  
One Year

Tn this study, four ecological factors were observed: solar radiation, air temperature, relative humidity and soil moisture. Of the four, solar radiation fluctuates more than any other and undoubtedly the other threefactors are influenced by solar radiation to a great extent. 1—Solar radiation varies widely with season and year. 2—The greatest intensity takes place during the months of June to September and the lowest from November to February. 3—The greatest intensity recorded under full sunlight was 1.91 gr. cal./ min./ cm.2 and the lowest was 1.35 gr. cal./ min./ cm.2. 4—The yearly average solar radiation under full sunlight was 144,754. 40 gr. cal./ cm.2. 5—The cumulative radiation for the 3 years that lasted the experiment was 434,263.20 gr. cal./ cm.2, under full sunlight. 6—Shade regulates solar radiation making it more uniform from one year to the other. 7-As solar radiation increases, growth and yield of coffee decrease. 8—Yield, and growth of coffee were definitely higher under 1/2 and 1/3 than under 2/3 and full sunlight. 9—Statistically significant differences in yield, were not found between plots with 1/2 and 1/3 sunlight. Growth was significantly higher under 1/3 exposure. 10—Radiation, produces distinctive formative effects on coffee. Plants under full sunlight were very weak, chlorotie and poorly developed. 11—Four ecological factors were measured: solar radiation, temperature, relative humidity and soil moisture. All are affected by radiation to a great extent, but other factors as vegetation have also some effect. 12—Solar radiation is negatively correlated with yields and growth. 13—Growth and yields are positively correlated. As expected low temperature and yield are associated and soil moisture acts independently in relation to growth. 14—Plants under full sunlight accumulated greater amounts of nitrogen and potash and to a less extent of phosphorous than under any other exposure. 15—An average of 53,143.20 gram calories per square centimeter per year is the optimum cumulative solar radiation for yield and growth of coffee. This amount is obtainable under natural shade of Guaba trees (Inga Inga) planted at not less than 16 x 16 feet.

scholarly journals Study on the improvement of indoor hot and humid environment in Tibetan-style residential areas in northwest Sichuan

2020 ◽  
Vol 165 ◽  
pp. 04074
Author(s):  
Sun Yidan
Keyword(s):  
Relative Humidity ◽  
Solar Radiation ◽  
Wall Temperature ◽  
Thermal Environment ◽  
Cold Weather ◽  
Living Room ◽  
Residential Areas ◽  
The West ◽  
Solar Radiation Intensity ◽  
Indoor And Outdoor

Indoor and outdoor thermal environment is under a definite impact on the human body, and to a large extent affects the comfort of people living. In this paper, the indoor and outdoor thermal and humidity parameters of Dongma village in the west of Sichuan Province were measured. On the living room and bedroom hot and humid comfort survey, the outside wall temperature and the local climate to do analysis, get January Dongma village typical residential indoor humidity environment, including the temperature of the living room is 6.6~19.5°C, the relative humidity is 28.9~45.3%rH, the bedroom temperature is 3.5~19.8°C, the relative humidity is 35.7~52.8%rH, the outdoor temperature is 2.4~27.4°C, the temperature in the east is -11.1~-3.3°C, -3.9~11.2°C at the west, -8~2.8°C at the south, -10.4~-2.5 °C at the north, 1.6~29.2 °C at the roof, and the solar radiation intensity is 422~739W/m^2. Combined with the above data, it is found that the overall insulation performance of the wall is good, but by the influence of the cold weather outside, the indoor temperature is still low, it is difficult to respond to the comfort needs of residents. The wall temperature is altered due to solar radiation. In view of the current situation of the indoor thermal environment in Dongma village, a series of optimization suggestions are submitted at the end of the paper.

INFLUENCE OF SOLAR RADIATION AND SOIL MOISTURE ON GROWTH AND YIELD OF CHINOOK WHEAT

1969 ◽  
Vol 49 (6) ◽  
pp. 685-699 ◽  
Author(s):  
C. A. Campbell ◽  
W. L. Pelton ◽  
K. F. Nielsen
Keyword(s):  
Soil Moisture ◽  
Solar Radiation ◽  
Light Intensity ◽  
Crude Protein ◽  
Soluble Sugars ◽  
Moisture Stress ◽  
Growth And Yield ◽  
Regression Equations ◽  
Soil Moisture Stress ◽  
Net Assimilation

The influence of solar radiation on the growth and yield of Chinook wheat was determined in a 5-year field shading study, and a 1-year, 3 × 3 shading × soil moisture lysimeter experiment.In the field, shading with saran mesh reduced solar radiation and wind but had little effect on air or soil temperature. In moist years shade maintained soil moisture at a higher level than no shade. Generally, mean leaf area ratio decreased and mean net assimilation rate and relative growth rate increased linearly with increases in the log of light intensity. There were interactions between shading × years (weather) relative to dry matter yield. The efficiency with which solar energy was used for grain production increased with shading. The effect of shading on crude protein and soluble sugars in grain was variable.In the lysimeter shading study, regression equations were used to relate several plant characters to shading and soil moisture (in the available range). Plant height, stem diameter, days to head, number of tillers, weights of grain and of straw, and percent cellulose were negatively related to soil moisture stress; crude protein was positively related. Days to head and crude protein were negatively related to light intensity, but all the other characters were positively related. The partial regression coefficients indicated that the influence of soil moisture stress was much more important than solar radiation on the crude protein content of the grain.

scholarly journals Environmental, economic and energetic benefits from implantation of several modes of solar collector movements

2021 ◽  
Vol 12 (3) ◽  
pp. 313-321
Author(s):  
Mustafa Hamad ◽  
Mhanna Obaid
Keyword(s):  
Solar System ◽  
Solar Radiation ◽  
Solar Collector ◽  
The Other ◽  
Tracking Systems ◽  
Optical Efficiency ◽  
Solar Radiation Intensity ◽  
Solar Radiation Incident ◽  
The One ◽  
East West

In this research, the performance of a moving solar system on two axes was studied, the east-west axis, this axis represents the tilt angle of the solar collector. The other movement is the surface's rotation around the perpendicular axis on the surface in the east and west directions, which in turn represents the azimuth angle of the solar collector. All possibilities for these movements were also studied, in order to reach the optimal option, which in turn depends on the importance of alication and the available space on the one hand, and the economic conditions on the other hand. The maximum value of solar radiation intensity was adopted as a guide to compare the performance of six options for tracking systems. Despite the high costs of tracking systems, they often have a positive economic return, as these systems increase the efficiency of the solar system, whether it is electric or thermal twice, the first one by increasing the intensity of the solar radiation incident on the solar collector, and the second one by increasing the optical efficiency of the solar collectors and thus increasing the overall efficiency of the device. The percentage of increase in the sixth type of solar energy is about 38% compared to the fixed mode. The minimum optical efficiency of the dual tracking mode has been found as 84%, while for fixed mode is about 48%.

Effect of shading at different times on the growth and yield of the potato

1976 ◽  
Vol 27 (4) ◽  
pp. 557 ◽  
Author(s):  
PJM Sale
Keyword(s):  
Dry Weight ◽  
The Other ◽  
Growth And Yield ◽  
Tuber Initiation ◽  
Full Sunlight ◽  
Tuber Bulking ◽  
Total Dry Weight ◽  
Bulking Rate

The effect of shading during the periods of new tuber initiation and subsequent bulking were studied with three crops of field-grown potatoes cv Sebago Plots were shaded (34% reduction on full sunlight) up to or after the stage when the young tubers had formed (3 weeks after the onset of initiation), receiving full sunlight for the other half of growth In other treatments plots were shaded throughout growth or not shaded at all In two experiments plots were split for two planting densities (7.14 and 14.28 tubers planted m-2), but density had no effect on the response to shade. Shade during the first part of growth did not affect the numbers of tubers initiation but, compared with unshaded plots, did reduce the numbers which reached a size of 1 cm in diameter or more, which was the same as the final numbers harvested at maturity Shade also delayed by a few days the onset of the rapid tuber-bulking period. Shade during later growth had some additional effect In reducing the maximum bulking rate achieved, so that the final yields from the differentially shaded plots were intermediate between those from the plots either unshaded or shaded throughout Plants receiving late shade had a higher percentage of their total dry weight In the haulm than did unshaded plants.

scholarly journals Sombreamento na produção inicial de hastes florais de Strelitzia reginae em Acorizal, MT

2015 ◽  
Vol 21 (1) ◽  
pp. 39
Author(s):  
Carmen Lúcia Ferreira Fava ◽  
Roseli Muniz Giachini ◽  
José Luiz da Silva ◽  
Mário Zortéa Antunes Júnior ◽  
Tonny José Araújo da Silva
Keyword(s):  
Relative Humidity ◽  
Environmental Factors ◽  
Solar Radiation ◽  
Production Process ◽  
Radiation Effect ◽  
The Other ◽  
Fresh Weight ◽  
Strelitzia Reginae ◽  
Medium Weight

The aim of this study was to evaluate the solar radiation effect in greenhouses for initial production of flower stalks of Strelitzia reginae. We evaluated number, height, diameter and fresh weight of buds and inflorescence lengths. The yield was higher in full sun, with 37 flower stalks and fresh weight of 100.2 g, followed by A3 environmental, with 24 rods and medium weight which did not differ significantly from the previous 18 and A5 showed rods with variables similar to previous environments, but with fresh weight (79.74 g) and diameters inferior to the other environments, while the A2 and A4 environments did not yield. The number, height, diameter and fresh weight of stems, reaching its highest values in environments with up to 30% shade and in conditions where light is limited, there is delay in the initial production of flower stalks. The radiation ensures the production process, but when it focuses directly on the plant, combined with other environmental factors like temperature and relative humidity, affects the pattern of trade of culture.

Stubble height effects on microclimate, yield and water use efficiency of spring wheat grown in a semiarid climate on the Canadian prairies

1997 ◽  
Vol 77 (3) ◽  
pp. 359-366 ◽  
Author(s):  
H. W. Cutforth ◽  
B. G. McConkey
Keyword(s):  
Solar Radiation ◽  
Water Use Efficiency ◽  
Water Use ◽  
Spring Wheat ◽  
Dry Matter ◽  
Soil Surface ◽  
The Other ◽  
Growth And Yield ◽  
Canadian Prairies ◽  
Use Efficiency

In the semiarid region of the western Canadian prairies, seeding directly into standing cereal stubble is gaining popularity. This four year study was conducted at Swift Current, SK, to determine how seeding into tall (>30 cm high), short (about 15 cm high) and cultivated cereal stubble altered the microclimate thereby affecting the growth and yield of hard red spring wheat (Triticum aestivum L.). The treatments were deployed immediately before seeding on plots that had overwintered with tall stubble. Seeding wheat into tall stubble increased grain yield and water use efficiency by about 12% compared to wheat seeded into cultivated stubble. Yield and water use efficiency for wheat seeded into short stubble were intermediate to the other stubble treatments. As well, wheat seeded into tall stubble grew taller than wheat seeded into the cultivated stubble. Further, there was a tendency for spring wheat grown in tall stubble to produce more dry matter and more leaf area, to have a lower proportion of dry matter as leaves and a higher proportion as stems, and to have a lower harvest index than the other treatments.Growing season evapotranspiration (ET) was not affected by stubble height. When the seedlings were small, compared to cultivated stubble, tall stubble altered the microclimate near the soil surface by reducing the daily average windspeed, soil temperature, and incoming solar radiation, and increasing the reflected solar radiation. Throughout much of the growing season, potential ET at the soil surface, measured with minilysimeters, was significantly lower in the tall stubble. Tall stubble, compared to cultivated stubble, increased the proportion of ET that was transpired by the wheat. As well, reduced windspeeds and increased photosynthetic area may have increased the efficiency of net carbon assimilation. To increase grain yields, producers in the semiarid prairies who direct-seed spring wheat are advised to seed into stubble left standing as tall as practical (at least 30 cm). Key words: Standing stubble, wheat, microclimate, water use, yield

Effect of storage system and sprout removal on post-harvest yam (Dioscorea spp.) fresh weight losses

1998 ◽  
Vol 130 (3) ◽  
pp. 329-336 ◽  
Author(s):  
O. GIRARDIN ◽  
C. NINDJIN ◽  
Z. FARAH ◽  
F. ESCHER ◽  
P. STAMP ◽  
...  
Keyword(s):  
Weight Loss ◽  
Relative Humidity ◽  
Solar Radiation ◽  
Storage Systems ◽  
Storage System ◽  
The Other ◽  
Fresh Weight ◽  
Effective Protection ◽  
Weight Losses ◽  
Range Of Variation

Two aspects of yam storage practice were tested from 1994 to 1995 in central Côte d'Ivoire. The first experiment compared the storage environment in pits or sheds with that of the traditional yam open barn method. The pits allowed the daily range of variation in temperature to be reduced while maintaining a high relative humidity (RH), whereas the temperature and RH in the sheds were similar to those of the yam barns. Differences in temperature and RH between the storage systems had little effect on the fresh weight losses of the tubers. The more effective protection against solar radiation and rain afforded by the sheds and pits reduced fresh weight losses in D. cayenensis rotundata by 12% over 6·5 months in comparison with the barns. The second experiment tested the regular removal of the sprouts. Sprout removal reduced fresh weight losses equally over 5 and 6 months' storage. The reduction in fresh weight loss was 12% for cv. Gnan (D. cayenensis rotundata) during 6 months' storage. Monthly sprout removal gave an equal benefit in pits, in sheds and on yam barns. The monthly cutting of sprouts at the base should be encouraged in places where this is not already done. The total loss is mainly determined by the growth of the sprouts and the reduction in weight after onset of sprouting, which are highly dependent on species and cultivar. Bètè bètè yams had better keeping qualities than all the other cultivars tested.

The effects of delayed planting and soil consolidation on potato yields

1966 ◽  
Vol 66 (2) ◽  
pp. 271-276 ◽  
Author(s):  
J. L. Beveridge
Keyword(s):  
Soil Moisture Content ◽  
Delay Period ◽  
The Other ◽  
Growth And Yield ◽  
Potato Seed ◽  
Soil Consolidation ◽  
Seed Tubers ◽  
Series Of Experiments ◽  
Potato Yields ◽  
One Year

1. Two series of experiments designed to investigate the effects of delaying planting potato seed tubers after drawing ridges in preparation for planting and of consolidation of soil beneath seed tubers on the growth and yield of potatoes are described and the results discussed.2. Delayed planting reduced the yield of saleable ware-size (> I¾ in.) tubers in one year by as much as 1.7 + 0.59 tons/acre, but had little effect in the other years, and it is argued that the effect was dependent on the tilth obtained in preparation for planting, the soil moisture content at the time the ridges were drawn, the amount of moisture lost during the delay period, and the rainfall after planting.

scholarly journals What’s the relative humidity in tropical caves?

PLoS ONE ◽  
2021 ◽  
Vol 16 (9) ◽  
pp. e0250396
Author(s):  
Luis Mejía-Ortíz ◽  
Mary C. Christman ◽  
Tanja Pipan ◽  
David C. Culver
Keyword(s):  
Global Warming ◽  
Relative Humidity ◽  
Large River ◽  
The Other ◽  
Quintana Roo ◽  
High Humidity ◽  
Dark Zone ◽  
Negative Effect ◽  
One Year ◽  
Strong Seasonality

Relative humidity (RH) was measured at hourly intervals for approximately one year in two caves at seven stations near Playa del Carmen in Quintana Roo, Mexico. Sistema Muévelo Rico is a 1.1 km long cave with 12 entrances and almost no dark zone. Río Secreto (Tuch) is a large river cave with more than 40 km of passages, and an extensive dark zone. Given the need for cave specialists to adapt to saturated humidity, presumably by cuticular thinning, the major stress of RH would be its deviation from saturation. RH in Río Secreto (Tuch) was invariant at three sites and displayed short deviations from 100% RH at the other four sites. These deviations were concentrated at the end of the nortes and beginning of the rainy season. Three of the sites in Sistema Muévelo Rico showed a similar pattern although the timing of the deviations from 100% RH was somewhat displaced. Four sites in Sistema Muévelo Rico were more variable, and were analyzed using a measure of amount of time of deviation from 100% RH for each 24 hour period. Strong seasonality was evident but, remarkably, periods of constant high humidity were not the same at all sites. In most Sistema Muévelo Rico sites, there was a detectable 24 hour cycle in RH, although it was quite weak in about half of them. For Río Secreto (Tuch) only one site showed any sign of a 24 hour cycle. The troglomorphic fauna was more or less uniformly spread throughout the caves and did not concentrate in any one area or set of RH conditions. Compared to temperature, RH is much more constant, perhaps even more constant than the amount of light. However, changes in RH as a result of global warming may have a major negative effect on the subterranean fauna.

scholarly journals Influence of Climatic Variables on Whole-plant Water use of Cocoa under Limited Soil Moisture Condition

2019 ◽  
pp. 1-8
Author(s):  
Femi S. Omotayo ◽  
Philip G. Oguntunde ◽  
Ayorinde A. Olufayo
Keyword(s):  
Soil Moisture ◽  
Relative Humidity ◽  
Solar Radiation ◽  
Correlation Coefficient ◽  
Water Use ◽  
Vapour Pressure ◽  
Plant Water ◽  
Plant Water Use ◽  
Whole Plant ◽  
Cocoa Plantation

Cocoa (Theobroma cacao L.) is a cash crop that is cultivated in many tropical regions of the world and is highly productive under favourable climatic conditions. Cocao, being originally an under storey tree of rainforests in tropical America, is traditionally cultivated below the canopy of shade trees. This study is carried out to establish the influence of climatic variables on whole-plant water use of cocoa under limited soil moisture conditions. An experimental plot was made in an even – aged 54 years old cocoa plantation which was demarcated while Water use measurement carried out for 20 consecutive days at the center of the cocoa plantation field at the Federal University of Technology, Akure using the temperature difference method (Sap flow meter). The results of evaporation rate and water consumed by crops led to decrease in soil water in the monitored root zone from 0.049 to 0.015 m3 m-3. Solar radiation reached a high value of 1002.37 Wm-2, with day time average of 238.02 Wm-2. Temperature ranges between 16.41 and 34.19ºC with a daily average of about 24.39ºC. Relative humidity varied from 98.60% to less than 32.37% with daily mean of around 74.90%. Vapour pressure varied from 0.01 to 2.87 kpa. The day time wind speeds rarely exceed 5.2 ms-1 while the daily averages were generally around 1.09 ms-1.  The results also show that transpiration, (Ec) is mostly influenced by solar radiation with a correlation coefficient of 0.71 while other variable like temperature, Vapour pressure deficit, and Relative humidity has correlation coefficient of 0.62, 0.50 and 0.58 respectively. The total amount of rainfall during the experiment was 38.9 mm. This shows that solar radiation has greater influence on the transpiration of the cocoa plant than other variables in the study area.

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