13,870 results on '"shading"'
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2. MATLAB/SIMULINK and Experimental Studies of Shading Effect on a Photovoltaic Array
- Author
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Mourad, Talbi and Mourad, Talbi
- Published
- 2025
- Full Text
- View/download PDF
3. A general albedo recovery approach for aerial photogrammetric images through inverse rendering.
- Author
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Song, Shuang and Qin, Rongjun
- Abstract
Modeling outdoor scenes for the synthetic 3D environment requires the recovery of reflectance/albedo information from raw images, which is an ill-posed problem due to the complicated unmodeled physics in this process (e.g., indirect lighting, volume scattering, specular reflection). The problem remains unsolved in a practical context. The recovered albedo can facilitate model relighting and shading, which can further enhance the realism of rendered models and the applications of digital twins. Typically, photogrammetric 3D models simply take the source images as texture materials, which inherently embed unwanted lighting artifacts (at the time of capture) into the texture. Therefore, these "polluted" textures are suboptimal for a synthetic environment to enable realistic rendering. In addition, these embedded environmental lightings further bring challenges to photo-consistencies across different images that cause image-matching uncertainties. This paper presents a general image formation model for albedo recovery from typical aerial photogrammetric images under natural illuminations and derives the inverse model to resolve the albedo information through inverse rendering intrinsic image decomposition. Our approach builds on the fact that both the sun illumination and scene geometry are estimable in aerial photogrammetry, thus they can provide direct inputs for this ill-posed problem. This physics-based approach does not require additional input other than data acquired through the typical drone-based photogrammetric collection and was shown to favorably outperform existing approaches. We also demonstrate that the recovered albedo image can in turn improve typical image processing tasks in photogrammetry such as feature and dense matching, edge, and line extraction. [This work extends our prior work "A Novel Intrinsic Image Decomposition Method to Recover Albedo for Aerial Images in Photogrammetry Processing" in ISPRS Congress 2022]. The code will be made available at github.com/GDAOSU/albedo_aerial_photogrammetry [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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4. Influence of steaming duration, chlorophyll‐a and ‐b content and ratio, and pH on the color of green tea processed from multiple tea (Camellia sinensisL.) cultivars.
- Author
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Hirono, Hisako, Yamashita, Shuya, and Hirono, Yuhei
- Subjects
- *
MULTIPLE regression analysis , *UMAMI (Taste) , *TEA , *MANUFACTURING processes , *CHEMICAL industry , *GREEN tea - Abstract
BACKGROUND: The color of green tea is an important quality indicator. In recent years, shading of tea (Camellia sinensis L.) plants has been widely adopted for green tea production to enhance its green color and umami taste. In this study, we identified factors that influence green tea color by (i) examining variation in the chlorophyll content of fresh new tea shoots among cultivars, cropping seasons, and the degree of shading, (ii) investigating the rate of conversion of chlorophyll to pheophytin during the tea manufacturing process, specifically with steaming duration, and (iii) analyzing the effects of the new tea shoot properties and the steaming process on colorimetric values of the steamed new tea shoots. RESULTS: Multiple regression analysis revealed that three factors contributed to the rate of conversion of each chlorophyll type to pheophytin in steamed new tea shoots (ranked by importance): steaming duration > each chlorophyll type (chlorophyll‐a and chlorophyll‐b) content of fresh new tea shoots > pH. The colorimetric hue angle (h) value of steamed new tea shoots was influenced by four factors (ranked by importance): steaming duration > total chlorophyll (chlorophyll‐a + chlorophyll‐b) content in fresh new tea shoots > pH > chlorophyll‐a/chlorophyll‐b ratio in fresh new tea shoots. CONCLUSION: Differences in the color of new tea shoots can be explained by the aforementioned four factors. The findings will be useful for cultivar selection, and determining the appropriate degree of shading and steaming duration, to produce high‐quality green teas with a good appearance. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
5. Light reduction and watering enhance flora memory awakening after forest topsoil translocation.
- Author
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Yuan, Chuang, Zhao, Gaojuan, Shen, Youxin, Chen, Fajun, Xu, Xiaoying, Fu, Xun, Lan, Ya, Hou, Zhengjun, Guo, Yibo, and Zhu, Xiai
- Subjects
- *
FOREST restoration , *FOREST degradation , *PLANT-water relationships , *BOTANY , *TOPSOIL - Abstract
Plant propagules are crucial flora memory materials in restoration practice. Awakening flora memory from plant propagules (i.e. seeds, root fragments, rhizomes, corms, and tubers) in the translocated topsoil from a donor site is a rapid method for forest restoration on degraded sites globally. However, it remains unclear to what extent manageable measures, such as light reduction and watering, affect flora memory awakening. We employed a quadratic saturation D‐optimal design in a forest topsoil translocation experiment to quantify the effects of light reduction and watering on flora memory awakening. We used the cumulative number and richness of plantlets emerging from plant propagules to represent the extent of flora memory awakening. Our results show that any combinations of light reduction and watering significantly increased both the cumulative number and richness of plantlets across different life forms. Light reduction had a significantly more positive effect on flora memory awakening than watering. Different life forms exhibited different parabolic or positive linear relationships in responses to light reduction and watering. Light reduction of about 60% of the degraded site and watering of about 80% of the donor site resulted in the highest number and richness of plantlets. We concluded that light reduction and watering combinations were effective in kick‐starting the flora memory awakening in a semiarid subtropical forest after topsoil translocation. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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6. Developing Guidelines for Azolla microphylla Production as Compost for Sustainable Agriculture.
- Author
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Thepsilvisut, Ornprapa, Srikan, Nuengruethai, Chutimanukul, Preuk, Marubodee, Rusama, and Ehara, Hiroshi
- Abstract
Azolla is a substitute compost that has the potential to enhance nutrient cycling in agricultural systems for sustainable development. In this study, four experiments were conducted to compare the Department of Agriculture (DOA, Thailand)'s methodology for determining the suitable type and rate of animal manure and the optimal light intensity for the growth and yield of Azolla (Azolla microphylla). The results revealed that applying 100% pig manure gave the highest yield of Azolla compared to the other manures. However, there was no discernible (p > 0.05) difference in yield across the various doses (20.16, 30.16, and 40.16 gN m
−2 ) of pig manure treatments, for which the minimal pig manure dosage of 20.16 gN m−2 was chosen. For further experimentation in the optimal light intensity, the 40% shading gave the highest yield of Azolla compared to no shading or 20 and 60% shading (p ≤ 0.01). When compared with the DOA Thailand methodology (1.27 kg m−2 of cow manure and covered with a size 32 mesh net), the findings indicated that the modified method (20.16 gN m−2 of pig manure + 40% shading) gave a 16% greater Azolla yield than that under the DOA Thailand methodology. The current finding method can produce a monthly fresh biomass of A. microphylla of 40.7 t ha−1 year−1 with higher contents of total N (4.92%) and lower C:N ratio (≤10:1) that could release minerals relatively rapidly. Its use can be encouraged by farmers to produce their own ecofriendly biofertilizer or soil amendment for sustainable agriculture. [ABSTRACT FROM AUTHOR]- Published
- 2024
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7. Optimizing Outdoor Thermal Comfort for Educational Buildings: Case Study in the City of Riyadh.
- Author
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Binabid, Jamil, Alymani, Abdulrahman, and Alammar, Ammar
- Abstract
In hot, arid climates, educational buildings often face the challenge of limited outdoor space usage. This research, through comprehensive simulation, aims to propose practical solutions to enhance outdoor thermal comfort, particularly during school break times and student dismissal periods, thereby fostering more comfortable and functional outdoor school environments. That will happen through achieving the main objective of the study, which is evaluating the suggested passive strategies. Riyadh was selected as the case study, and four representative schools were analyzed through simulation and optimization processes to identify key areas for improvement. The research leveraged simulation tools such as Ladybug and Grasshopper in Rhino, highlighting the practicality and impact of this approach. Simulations were performed to assess the existing outdoor thermal conditions using the universal thermal climate index (UTCI) and to pinpoint regions with elevated thermal discomfort. Passive design interventions, such as shading devices and vegetation, were explored and optimized using the Galapagos in Grasshopper. This methodology supports the originality of this research in its integration of simulation tools, such as Ladybug and Grasshopper, with optimization techniques using the Galapagos plugin, specifically applied to the unique site-specific context of educational outdoor environments in a hot, dry climate in Riyadh. Additionally, insights for urban planners and architects demonstrate the possibility of integrating passive design principles to improve the usability and sustainability of outdoor spaces. The findings indicated that fewer apertures in shade devices combined with greater tree canopies might double the effectivity in lowering UTCI values, thereby enhancing thermal comfort, especially during peak summer months. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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8. Varying levels of natural light intensity affect the phyto-biochemical compounds, antioxidant indices and genes involved in the monoterpene biosynthetic pathway of Origanum majorana L.
- Author
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Hashemifar, Zahra, Sanjarian, Forough, Naghdi Badi, Hassanali, and Mehrafarin, Ali
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ORIGANUM , *LIGHT intensity , *GENE expression , *ESSENTIAL oils , *CYTOCHROME P-450 , *MONOTERPENES - Abstract
Background: Light is a critical environmental factor in plants, encompassing two vital aspects: intensity and quality. To assess the influence of different light intensities on Origanum majorana L., pots containing the herb were subjected to four levels of light intensity: 20, 50, 70, and 100% natural light. After a 60-day treatment period, the plants were evaluated for metabolite production, including total sugar content, protein, dry weight, antioxidant indices, expression of monoterpenes biosynthesis genes, and essential oil compounds. The experimental design followed a randomized complete blocks format, and statistical analysis of variance was conducted. Results: The results indicated a correlation between increased light intensity and elevated total sugar and protein content, which contributed to improved plant dry weight. The highest levels of hydrogen peroxide and malondialdehyde (MDA) were observed under 100% light intensity. Catalase and superoxide dismutase enzymes exhibited increased activity, with a 4.23-fold and 2.14-fold increase, respectively, under full light. In contrast, peroxidase and polyphenol oxidase enzyme activities decreased by 3.29-fold and 3.24-fold, respectively. As light intensity increases, the expression level of the 1-deoxy-D-xylulose 5-phosphate reductoisomerase (DXR) gene increases. However, beyond a light intensity of 70%, the DXR gene expression level decreased. Furthermore, the expression levels of the cytochrome P450 genes CYP71D178 and CYP71D179 exhibited an increasing trend in response to elevated light intensity. Essential oil content increased from 0.02 to 0.5% until reaching 70% light intensity. However, with further increases in light intensity, the essential oil content decreased by 54 to 0.23%. Conclusions: These findings emphasize the importance of balancing plant growth promotion and stress management under different light conditions. The research suggests that sweet marjoram plants thrive best in unshaded open spaces, resulting in maximum biomass. However, essential oil production decreases under the same conditions. For farmers in areas with an average light intensity of approximately 1700 µmol m−2s−1, it is recommended to cultivate sweet marjoram in shade-free fields to optimize biomass and essential oil production. Towards the end of the growth cycle, it is advisable to use shades that allow 70% of light to pass through. The specific duration of shade implementation can be further explored in future research. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
9. Blind Separation of Skin Chromophores from Multispectral Dermatological Images.
- Author
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Zokay, Mustapha and Saylani, Hicham
- Subjects
- *
BLIND source separation , *MULTISPECTRAL imaging , *DEOXYHEMOGLOBIN , *CHROMOPHORES , *OXYHEMOGLOBIN - Abstract
Background/Objectives: Based on Blind Source Separation and the use of multispectral imaging, the new approach we propose in this paper aims to improve the estimation of the concentrations of the main skin chromophores (melanin, oxyhemoglobin and deoxyhemoglobin), while considering shading as a fully-fledged source. Methods: In this paper, we demonstrate that the use of the Infra-Red spectral band, in addition to the traditional RGB spectral bands of dermatological images, allows us to model the image provided by each spectral band as a mixture of the concentrations of the three chromophores in addition to that of the shading, which are estimated through four steps using Blind Source Separation. Results: We studied the performance of our new method on a database of real multispectral dermatological images of melanoma by proposing a new quantitative performances measurement criterion based on mutual information. We then validated these performances on a database of multispectral dermatological images that we simulated using our own new protocol. Conclusions: All the results obtained demonstrated the effectiveness of our new approach for estimating the concentrations of the skin chromophores from a multispectral dermatological image, compared to traditional approaches that consist of using only the RGB image by neglecting shading. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
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10. Algal turf accrues both costs and benefits to growth via association with adjacent stands of Turbinaria ornata, a rapidly expanding macroalga in the South Pacific.
- Author
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Cheh, Adrian S., Hollander, Erin N. R., Condon, Tom, Grier, Shalanda R., and Fong, Peggy
- Subjects
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CORAL reefs & islands , *CORALS , *MARINE algae , *GRAZING , *HERBIVORES - Abstract
Algal turf on coral reefs can transition from short productive forms to longer less productive forms that often form a persistent degraded state. We evaluated whether adjacent communities, such as stands of the macroalga Turbinaria ornata, can drive these transitions in Moorea, French Polynesia. We first found that T. ornata stands that overhang turf reduced growth as restricting canopy movement increased turf height compared to controls, implying an overhanging T. ornata canopy shades or abrades adjacent turf. Second, we manipulated T. ornata presence (intact/completely removed) and herbivore access (uncaged/caged) and found that, in the presence of herbivores, removal of stands reduced the height of adjacent turf compared to plots adjacent to intact Turbinaria stands. The presence of intact stands also deterred grazing, demonstrating they provide a refuge for adjacent turf. Thus, algal turf derives both benefits and costs of proximity to macroalgal stands. It is imperative to explore the relative strengths of these costs and benefits as these interactions may drive local transitions to degraded algal states. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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11. What determines transfer of carbon from plants to mycorrhizal fungi?
- Author
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Bunn, Rebecca A., Corrêa, Ana, Joshi, Jaya, Kaiser, Christina, Lekberg, Ylva, Prescott, Cindy E., Sala, Anna, and Karst, Justine
- Abstract
Summary Biological Market Models are common evolutionary frameworks to understand the maintenance of mutualism in mycorrhizas. ‘Surplus C’ hypotheses provide an alternative framework where stoichiometry and source–sink dynamics govern mycorrhizal function. A critical difference between these frameworks is whether carbon transfer from plants is regulated by nutrient transfer from fungi or through source–sink dynamics. In this review, we: provide a historical perspective; summarize studies that asked whether plants transfer more carbon to fungi that transfer more nutrients; conduct a meta‐analysis to assess whether mycorrhizal plant growth suppressions are related to carbon transfer; and review literature on cellular mechanisms for carbon transfer. In sum, current knowledge does not indicate that carbon transfer from plants is directly regulated by nutrient delivery from fungi. Further, mycorrhizal plant growth responses were linked to nutrient uptake rather than carbon transfer. These findings are more consistent with ‘Surplus C’ hypotheses than Biological Market Models. However, we also identify research gaps, and future research may uncover a mechanism directly linking carbon and nutrient transfer. Until then, we urge caution when applying economic terminology to describe mycorrhizas. We present a synthesis of ideas, consider knowledge gaps, and suggest experiments to advance the field. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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12. 基于神经辐射场遮挡优化的单视图三维重建方法.
- Author
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陈志杰, 邓慧萍, 向 森, and 吴 谨
- Subjects
CONVOLUTIONAL neural networks ,TRANSFORMER models ,ARCHITECTURAL design ,GLOBAL method of teaching ,PYRAMIDS - Abstract
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- Published
- 2024
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13. Estimation of Cucumber Fruit Yield Cultivated Under Different Light Conditions in Greenhouses.
- Author
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Hong, Inseo, Yu, Jin, Hwang, Seung Jae, and Kwack, Yurina
- Subjects
CROP quality ,FRUIT yield ,GREENHOUSE plants ,CROP yields ,CROP growth ,CUCUMBERS - Abstract
In recent years, an increase in the frequency of low-sunlight conditions due to climate change has resulted in a decline in the yield and quality of crops for greenhouse farmers, leading to significant challenges in maintaining optimal plant growth. The crop growth model can be used to predict changes in cucumber yield in response to variations in sunlight, which can help efficiently address sunlight shortages. The objective of this study was to improve and validate the model for predicting cucumber yield under different light environment conditions, including shading and supplemental lighting. The model comprises three steps: LAI prediction, daily assimilate yield prediction, and fruit yield prediction, each of which involves modifying the coefficients applied to suit the cucumber cultivar and environment condition. The improved model demonstrated a high degree of accuracy in predicting cucumber yields in the control and low-sunlight treatments (10, 20, and 30% shading), with a coefficient of determination (R
2 ) > 0.98. When supplemental lighting was incorporated into the control and shading treatments, the accuracy of the improved model in predicting cucumber yield was also high, with a coefficient of determination (R2 ) > 0.99. The model also accurately predicted the decrease in cucumber fruit yield under low-sunlight conditions (shading treatments) and the increase in yield due to supplemental lighting. The findings of this study indicate that the improved cucumber yield prediction model can be applied to assess the efficacy of yield reduction in low-sunlight conditions and the potential for yield enhancement through supplemental lighting. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
14. Varying levels of natural light intensity affect the phyto-biochemical compounds, antioxidant indices and genes involved in the monoterpene biosynthetic pathway of Origanum majorana L.
- Author
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Zahra Hashemifar, Forough Sanjarian, Hassanali Naghdi Badi, and Ali Mehrafarin
- Subjects
Abiotic stress ,Lamiaceae ,Majoram ,Shading ,Sustainable agriculture ,Thymol ,Botany ,QK1-989 - Abstract
Abstract Background Light is a critical environmental factor in plants, encompassing two vital aspects: intensity and quality. To assess the influence of different light intensities on Origanum majorana L., pots containing the herb were subjected to four levels of light intensity: 20, 50, 70, and 100% natural light. After a 60-day treatment period, the plants were evaluated for metabolite production, including total sugar content, protein, dry weight, antioxidant indices, expression of monoterpenes biosynthesis genes, and essential oil compounds. The experimental design followed a randomized complete blocks format, and statistical analysis of variance was conducted. Results The results indicated a correlation between increased light intensity and elevated total sugar and protein content, which contributed to improved plant dry weight. The highest levels of hydrogen peroxide and malondialdehyde (MDA) were observed under 100% light intensity. Catalase and superoxide dismutase enzymes exhibited increased activity, with a 4.23-fold and 2.14-fold increase, respectively, under full light. In contrast, peroxidase and polyphenol oxidase enzyme activities decreased by 3.29-fold and 3.24-fold, respectively. As light intensity increases, the expression level of the 1-deoxy-D-xylulose 5-phosphate reductoisomerase (DXR) gene increases. However, beyond a light intensity of 70%, the DXR gene expression level decreased. Furthermore, the expression levels of the cytochrome P450 genes CYP71D178 and CYP71D179 exhibited an increasing trend in response to elevated light intensity. Essential oil content increased from 0.02 to 0.5% until reaching 70% light intensity. However, with further increases in light intensity, the essential oil content decreased by 54 to 0.23%. Conclusions These findings emphasize the importance of balancing plant growth promotion and stress management under different light conditions. The research suggests that sweet marjoram plants thrive best in unshaded open spaces, resulting in maximum biomass. However, essential oil production decreases under the same conditions. For farmers in areas with an average light intensity of approximately 1700 µmol m−2s−1, it is recommended to cultivate sweet marjoram in shade-free fields to optimize biomass and essential oil production. Towards the end of the growth cycle, it is advisable to use shades that allow 70% of light to pass through. The specific duration of shade implementation can be further explored in future research.
- Published
- 2024
- Full Text
- View/download PDF
15. (Effect of shading and spraying with alcoholic sugars on the physiological lifespan of Seeds celery plant)
- Author
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Omar Harby and Hmood G. Khaleefa
- Subjects
shading ,light ,spraying ,sugar alcohols ,celery ,Agriculture - Abstract
The experiment was carried out at the research station north Ramadi city of the College of Agriculture – University Of Anbar to study the effect of shading and spraying with sugar alcohols (sorbitol) on the physiological lifespan of celery (Apium graveolens L.). The experiment included two levels of shading (0 without shading and 50%) with symbols (S0 and S1) sequentially and spraying with sugar alcohols (sorbitol) at three levels (spraying with distilled water only, 10 and 20 mg L-1) with symbols (K0,K1 and K2) sequentially. The characteristics of plant height, stem diameter, chlorophyll content of leaves, number of days from planting to flowering, number of days required for complete flowering and number of days required for seed maturation were studied.The results showed that the percentage of shading S1 (50%) led to a significant increase in stem diameter and the chlorophyll content of the leaves, while the level of shading S0 (with out shading) significantly increased the height of the plant, the number of days from planting to flowering, the number of days required for full flowering, and the number of days required for seed maturity. As for the spraying factor with alcoholic sugars, the spraying level K3 (20mg L-1) was significantly superior in stem diameter and the chlorophyll content of the leaves. As for spraying with distilled water only, it was significantly superior in the number of days from planting to flowering, the number of days required for complete flowering, and the number of days required for seed maturity.
- Published
- 2024
- Full Text
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16. Effects of shading on the photosynthetic characteristics and leaf structure of Ranunculus ternatus Thunb.
- Author
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WANG Li, ZHAO Dandan, and ZHANG Gexiang
- Subjects
ranunculus ternatus thunb. ,shading ,photosynthetic characteristics ,leaf anatomical structure ,Biology (General) ,QH301-705.5 ,Botany ,QK1-989 - Abstract
Abstract [Objective] The study aims to investigate the effects of different shading levels on the photosynthetic characteristics and leaf anatomical structure of wild plant Ranunculus ternatus Thunb. and provide a theoretical basis for the in-depth understanding of its shading tolerance and large-scale planting. [Methods] This experiment adopts the method of controlling variables with R. ternatus Thunb. as materials. Five shading treatments full light (CK), 30% shading (T1), 50% shading (T2), 70% shading (T3), and 90% shading (T4), were applied. [Results] (1) With the increase of shading, the leaf area reached the maximum under T3 environment. Plant height and stem diameter were decreased with the decrease of light. (2) With the increase of shading, the leaf apparent quantum efficiency (AQE) of R. ternatus was first increased and then decreased, and was lower than other treatments under T4 treatment. Light saturation point (LSP), light compensation point (LCP), dark respiration rate (Rd), and maximum net photosynthetic rate (Pn,max) were decreased gradually. Maximum fluorescence (Fm), variable fluorescence (Fv), maximized chemical efficiency (Fv/Fm), and PSⅡ potential activity (Fv/Fo) were increased first and then decreased, while the electron ratio of heat dissipation (φDo) and the initial fluorescence (Fo) was decreased first and then increased. (3) With the increase of shading, the stomatal density of R. ternatus was first decreased and then increased, and reached the minimum value at T3 treatment. The thickness of the upper and lower epidermis and the thickness of the sponge gradually were decreased, the tissue structure compactness (CTR) was decreased first and then increased, and the tissue structure porosity (SR) was first increased and then decreased. (4) Leaf palisade tissue, sponge tissue, leaf thickness, and upper, and lower epidermal thickness were positively correlated with Rd. Sponge tissue thickness (ST), CTR, and SR were positively correlated with Pn,max. P/S and SR were positively correlated with AQE. However, sponge tissue thickness (ST) and SR were negatively correlated with Fo. [Conclusion] R. ternatus can improve its shading tolerance by reducing photosynthetic rates and changing leaf structures; it grows well in full light and adapts to 30%-70% shading environment.
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- 2024
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17. 低纬度海岛太阳能建筑逆向热工设计方法.
- Author
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何知衡, 杨雯1., and 刘加平
- Subjects
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POWER resources , *ENERGY consumption , *SOLAR energy , *BUILDING protection , *PHOTOVOLTAIC power systems , *ENERGY consumption of buildings - Abstract
To fully utilize solar energy resources for ultra-low energy consumption buildings and create green and livable environments on island reefs, we proposed the "full shading" design principle for build- ings under extreme hot and humid conditions for the first time, An innovative "reverse" thermal design method was developed that couples solar photovoltaic cooling systems with heat protection design for buildings, and a new model of ultra-low energy consumption buildings suitable for low-latitude islands was formed. Experimental and engineering practice results show that full shading design can significantly reduce air conditioning load and energy consumption, For example in the demonstration building on Meiji Island in the South China Sea, the air conditioning load can be reduced by more than 30% after imple- menting the full shading design. By following the reverse thermal design principles, it is possible to signif- icantly improve the thermal transmittance limits of exterior walls, roofs, and windows of marine build- ings.achieving comfortable indoor conditions solely relying on solar energy. The new model of ultra-low energy consumption buildings for low-latitude islands can effectively reduce dependence on building e- quipment and create a more comfortable indoor thermal environment at the building level. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
18. A comprehensive review of matcha: production, food application, potential health benefits, and gastrointestinal fate of main phenolics.
- Author
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Ye, Jian-Hui, Fang, Qi-Ting, Zeng, Lin, Liu, Ru-Yi, Lu, Lu, Dong, Jun-Jie, Yin, Jun-Feng, Liang, Yue-Rong, Xu, Yong-Quan, and Liu, Zhong-Hua
- Subjects
- *
ELEMENTAL diet , *UMAMI (Taste) , *MANUFACTURING processes , *BAKED products , *TEA growing - Abstract
Matcha, a powder processed from tea leaves, has a unique green tea flavor and appealing color, in addition to many other sought after functional properties for a wide range of formulated food applications (e.g., dairy products, bakery products, and beverage). The properties of matcha are influenced by cultivation method and processing post-harvest. The transition from drinking tea infusion to eating whole leaves provides a healthy option for the delivery of functional component and tea phenolics in various food matrix. The aim of this review is to describe the physico-chemical properties of matcha, the specific requirements for tea cultivation and industrial processing. The quality of matcha mainly depends on the quality of fresh tea leaves, which is affected by preharvest factors including tea cultivar, shading treatment, and fertilization. Shading is the key measure to increase greenness, reduce bitterness and astringency, and enhance umami taste of matcha. The potential health benefits of matcha and the gastrointestinal fate of main phenolics in matcha are covered. The chemical compositions and bioactivities of fiber-bound phenolics in matcha and other plant materials are discussed. The fiber-bound phenolics are considered promising components which endow matcha with boosted bioavailability of phenolics and health benefits through modulating gut microbiota. [ABSTRACT FROM AUTHOR]
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- 2024
- Full Text
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19. Optimization Strategy for Thermal Comfort in Railway Stations above Ground Level in Beijing.
- Author
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Li, Xiangyu, Shi, Wenxi, Liu, Yixuan, and Zhang, Nan
- Subjects
THERMAL comfort ,PUBLIC transit ,WINDOW shades ,FIELD research ,WIND speed - Abstract
Urban rail transit, a convenient and fast public transportation mode with rapid construction and development, occupies fewer land resources and accommodates large passenger volumes. However, thermal comfort should be given more attention. Stations above ground level experience poor thermal comfort on the platforms, especially in hot summers. This study combines field research with a simulation analysis to propose a strategy for improving thermal comfort on above-ground urban rail transit platforms. This study analyzed the effects of the skylight opening rate, side window opening rate, design of transparent maintenance structure shading, and the platform profile shape on the thermal comfort of above-ground stations using field research, comparative experiments, and a simulation analysis with the PHOENICS (Command Prompt) software. The results indicate that adding longitudinal sunshade louvers to the skylight of the station platform is a cost-effective method to reduce the average temperature and PMV value, thereby improving thermal comfort. Increasing the skylight opening rate can result in a temperature rise. Adjusting the opening rate of the side windows to 20% and adding sun-shading louvers can also significantly enhance the station's thermal comfort. Taking Wudaokou Station on Beijing Line 13 as an example, the simultaneous installation of additional longitudinal skylight shading and side window shading and increasing the side window opening rate to 20% on the platform resulted in a 2.6 °C decrease in the average temperature, a 4.7% increase in the average wind speed, and a 0.62 decrease in the PMV value, significantly enhancing thermal comfort for passengers. This study confirms that optimizing shading and ventilation systems can significantly reduce the platform temperature and improve passengers' thermal comfort. This study provides theoretical support and innovative methods for optimizing thermal environments in similar environments. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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20. Investigating the interactive effects of habitat type and light intensity on rocky shores.
- Author
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Schaefer, Nina, Dafforn, Katherine A., Johnston, Emma L., Clark, Graeme F., and Mayer-Pinto, Mariana
- Subjects
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ARTIFICIAL habitats , *BIOTIC communities , *LIGHT transmission , *LIGHT intensity , *SPECIES pools - Abstract
Light availability and habitat complexity are two key drivers of community assembly. Urbanisation has been shown to affect both, with important consequences to ecological communities. On the intertidal, for instance, studies have shown that light intensity is greater on natural rocky shores than on less complex artificial habitats (seawalls), though different habitats can also experience similar light intensities, for example when shaded by urban structures. Understanding therefore how these factors individually, and combined, affect communities is important to understand the mechanisms driving changes in community structure, and consequently provide solutions to tackle the increasing homogenisation of habitats and lightscapes in urbanised spaces through smart infrastructure designs. Here, we assessed how different light levels affect the recruitment of communities in rock pools and on emergent rock on an intertidal rocky shore. We cleared 30 patches of emergent rock and 30 rock pools and manipulated light using shades with different light transmissions (full light, procedural control, 75%, 35%, and 15% light transmission, full shade) and assessed mobile and sessile communities monthly for 6 months. Effects of reducing light levels were generally stronger on rock than in pools. Fully shaded plots supported double the amount of mobile organisms than plots in full sunlight, in both habitats. Algal cover was higher in pools compared to rock, and at intermediate light levels, but effects varied with site. This study highlights the importance of variable light conditions and different habitats for rocky shore communities, which should be considered in future coastal developments to retain natural biodiversity. [ABSTRACT FROM AUTHOR]
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- 2024
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21. The light intensity in the cultivation environment and the impact of glyphosate on plants of the Urochloa genus.
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Augustus Vasconcelos de Oliveira, Victor, Silva Donato, Luan Mateus, Ruas, Murilo Antônio Oliveira, Oliveira, José Ângeles Moreira de, Fernandes de Souza, Richardson, and Tuffi Santos, Leonardo David
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GLYPHOSATE , *SIGNALGRASS , *LIGHT intensity , *PHOTOSYNTHETICALLY active radiation (PAR) , *HERBICIDES , *QUANTUM efficiency , *ELECTRON transport - Abstract
The variation in light within the environment triggers morphophysiological changes in plants and can lead to distinct responses in sun-exposed or shaded plants to glyphosate. The response of Urochloa genotypes subjected to desiccation with 2160, 1622.4, 1080, 524.4, 273.6, and 0.0 g ha−1 of glyphosate was evaluated in full sun and shade conditions. Cayana grass, mulato II grass, and sabiá grass – hybrids recently launched on the market, in addition to palisade grass and congo grass were evaluated. Under full sun, we achieved control of congo grass using 1080 g ha−1 of glyphosate, while the other grasses required 2160 g ha−1. In the low-light environment, sabiá grass was effectively controlled with 524.4 g ha−1 of glyphosate, but the other grasses needed 273.6 g ha−1. In shading, compared to full sun, the savings with glyphosate were 75 and 76% for the control of congo grass and sabiá grass, respectively, and 87% for palisade grass, mulato II grass and cayana grass. Increasing glyphosate doses leads to a decline in the quantum efficiency of photosystem II and in the electron transport rate, especially in the shade. Urochloa genotypes are more sensitive to glyphosate in the shade, which must be considered when determining the herbicide dose. [ABSTRACT FROM AUTHOR]
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- 2024
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22. 遮荫对花生形态结构可塑性的影响.
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刘 柱, 谢立勇, 张 正, 赵新华, 南镇武, 孟维伟, and 万书波
- Abstract
Copyright of Journal of Shenyang Agricultural University is the property of Journal of Shenyang Agricultural University Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
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- 2024
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23. The potential of agroforestry to buffer climate change impacts on suitability of coffee and banana in Uganda.
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Abigaba, David, Chemura, Abel, Gornott, Christoph, and Schauberger, Bernhard
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CLIMATE change adaptation ,COFFEE growing ,REGRESSION trees ,COFFEE ,AGROFORESTRY ,RANDOM forest algorithms - Abstract
Coffee, an important global commodity, is threatened by climate change. Agroforestry has been considered as one option to maintain or enhance coffee production. In this study, we use a machine learning ensemble consisting of MaxEnt, Random Forest and Boosted Regression Trees to assess climate change impacts on the suitability to grow Arabica coffee, Robusta coffee and bananas in Uganda by 2050. Based on this, the buffering potential of Cordia africana and Ficus natalensis, the two commonly used shading trees in agroforestry systems is assessed. Our robust models (AUC of 0.7–0.9) indicate temperature-related variables as relevant for Arabica coffee suitability, while precipitation-related variables determine Robusta coffee and banana suitability. Under current climatic conditions, only a quarter of the total land area is suitable for growing Arabica coffee, while over three-quarters are suitable for Robusta coffee and bananas. Our results suggest that climate change will reduce the area suitable to grow Arabica coffee, Robusta coffee and bananas by 20%, 9% and 3.5%, respectively, under SSP3-RCP7.0 by 2050. A shift in areas suitable for Arabica coffee to highlands might occur, leading to potential encroachment on protected areas. In our model, implementing agroforestry with up to 50% shading could partially offset suitable area losses for Robusta coffee—but not for Arabica coffee. The potential to produce valuable Arabica coffee thus decreases under climate change and cannot be averted by agroforestry. We conclude that the implementation and design of agroforestry must be based on species, elevation, and regional climate projections to avoid maladaptation. [ABSTRACT FROM AUTHOR]
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- 2024
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24. Single-Sensor Global MPPT for PV System Interconnected with DC Link Using Recent Red-Tailed Hawk Algorithm.
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Almousa, Motab Turki, Gomaa, Mohamed R., Ghasemi, Mostafa, and Louzazni, Mohamed
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OPTIMIZATION algorithms , *PARTICLE swarm optimization , *PHOTOVOLTAIC power systems , *GRANULAR flow , *AUTHORSHIP - Abstract
The primary disadvantage of solar photovoltaic systems, particularly in partial shadowing conditions (PSC), is their low efficiency. A power–voltage curve with a homogenous distribution of solar irradiation often has a single maximum power point (MPP). Without a doubt, it can be extracted using any conventional tracker—for instance, perturb and observe. On the other hand, under PSC, the situation is entirely different since, depending on the number of distinct solar irradiation levels, the power–voltage curve has numerous MPPs (i.e., multiple local points and one global point). Conventional MPPTs can only extract the first point since they are unable to distinguish between local and global MPP. Thus, to track the global MPP, an optimized MPPT based on optimization algorithms is needed. The majority of global MPPT techniques seen in the literature call for sensors for voltage and current in addition to, occasionally, temperature and/or solar irradiance, which raises the cost of the system. Therefore, a single-sensor global MPPT based on the recent red-tailed hawk (RTH) algorithm for a PV system interconnected with a DC link operating under PSC is presented. Reducing the number of sensors leads to a decrease in the cost of a controller. To prove the superiority of the RTH, the results are compared with several metaheuristic algorithms. Three shading scenarios are considered, with the idea of changing the shading scenario to change the location of the global MPP to measure the consistency of the algorithms. The results verified the effectiveness of the suggested global MPPT based on the RTH in precisely capturing the global MPP compared with other methods. As an example, for the first shading situation, the mean PV power values varied between 6835.63 W and 5925.58 W. The RTH reaches the highest PV power of 6835.63 W flowing through particle swarm optimization (6808.64 W), whereas greylag goose optimizer achieved the smallest PV power production of 5925.58 W. [ABSTRACT FROM AUTHOR]
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- 2024
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25. Combining modeling and experimental approaches for developing rice–oil palm agroforestry systems.
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Perez, Raphaël P A, Vezy, Rémi, Bordon, Romain, Laisné, Thomas, Roques, Sandrine, Rebolledo, Maria-Camila, Rouan, Lauriane, Fabre, Denis, Gibert, Olivier, and Raissac, Marcel De
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- *
AGROFORESTRY , *OIL palm , *RICE , *RICE oil , *EXTREME weather , *WATER efficiency , *CLIMATE extremes , *PRODUCTION losses - Abstract
Monoculture systems in South East Asia are facing challenges due to climate change-induced extreme weather conditions, leading to significant annual production losses in rice and oil palm. To ensure the stability of these crops, innovative strategies like resilient agroforestry systems need to be explored. Converting oil palm (Elaeis guineensis) monocultures to rice (Oryza sativa)-based intercropping systems shows promise, but achieving optimal yields requires adjusting palm density and identifying rice varieties adapted to changes in light quantity and diurnal fluctuation. This paper proposes a methodology that combines a model of light interception with indoor experiments to assess the feasibility of rice–oil palm agroforestry systems. Using a functional–structural plant model of oil palm, the planting design was optimized to maximize transmitted light for rice. Simulation results estimated the potential impact on oil palm carbon assimilation and transpiration. In growth chambers, simulated light conditions were replicated with adjustments to intensity and daily fluctuation. Three light treatments independently evaluated the effects of light intensity and fluctuation on different rice accessions. The simulation study revealed intercropping designs that significantly increased light transmission for rice cultivation with minimal decrease in oil palm densities compared with conventional designs. The results estimated a loss in oil palm productivity of less than 10%, attributed to improved carbon assimilation and water use efficiency. Changes in rice plant architecture were primarily influenced by light quantity, while variations in yield components were attributed to light fluctuations. Different rice accessions exhibited diverse responses to light fluctuations, indicating the potential for selecting genotypes suitable for agroforestry systems. [ABSTRACT FROM AUTHOR]
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- 2024
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26. Spatially-Varying Illumination-Aware Indoor Harmonization.
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Hu, Zhongyun, Li, Jiahao, Wang, Xue, and Wang, Qing
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- *
ARTIFICIAL neural networks - Abstract
In this paper, we address the problem of spatially-varying illumination-aware indoor harmonization. Existing image harmonization works either focus on extracting no more than 2D information (e.g., low-level statistics or image filters) from the background image or rely on the non-linear representations of deep neural networks to adjust the foreground appearance. However, from a physical point of view, realistic image harmonization requires the perception of illumination at the foreground position in the scene (i.e., Spatially-Varying (SV) illumination), especially for indoor scenes. To solve indoor harmonization, we present a novel learning-based framework, which attempts to mimic the physical model of image formation. The proposed framework consists of a new neural harmonization architecture with four compact neural modules, which jointly learn SV illumination, shading, albedo, and rendering. In particular, a multilayer perceptron-based neural illumination field is designed to recover the illumination with finer details. Besides, we construct the first large-scale synthetic indoor harmonization benchmark dataset in which the foreground focuses on humans and is rendered and perturbed by SV illuminations. An object placement formula is also derived to ensure that the foreground object is placed in the background at a reasonable size. Extensive experiments on synthetic and real data demonstrate that our proposed approach achieves better results than prior works. [ABSTRACT FROM AUTHOR]
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- 2024
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27. The potential of shading to optimize the performance ratio of a solar power system
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Muhammad Dihyah Marwan, Suhono Suhono, and Lukman Subekti
- Subjects
Azimuth ,Performance ratio ,Photovoltaic ,Shading ,Tilt ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 - Abstract
The aim of this research is to investigate the effect of shading to evaluate the performance ratio (PR) of a solar power system. In order to accomplish the objective of this study, the PVsyst software was utilized to assess the impact of shading, generate an energy input/output loss diagram and determine the PR during the entire year. This work only considers shading effect due to the position of a building and the location of the PV site. The suggested method also evaluates the financial analysis of the proposed PV system, specifically focusing on the payback period (PBP) and return on investment (ROI). Two types of perspective design of the PV position for the values of tilt and azimuth have been evaluated. The value of tilt and azimuth were 15o and 0° for design-1 and design-2 with different perspective, such as North building and South building for design-1 and design-2, respectively. The result of optimization illustrated that the PR yearly levels for Designs-1 and 2, were 0.821 and 0.759, respectively. In addition, the financial analysis investigated to examine PBP and ROI, were 8.1 years with 140.5 % return rate; 8.7 years with 110 % return rate, respectively. The proposed method has been simulated and analysed for applied on the rooftop of Teaching Industrial Learning Centre building, the University of Gadjah Mada (UGM) Yogyakarta-Indonesia.
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- 2024
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28. An Approach of Colored Shade Nets on Photosynthetic Efficiency of Capsicum chinense and Capsicum frutescens
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Renata Ranielly Pedroza Cruz, Ariana Mota Pereira, Erli Pinto dos Santos, Toshik Iarley da Silva, Felipe Douglas Ferreira, Wellington Souto Ribeiro, Luiz Alexandre Peternelli, and José Antônio Saraiva Grossi
- Subjects
chlorophyll fluorescence ,dry matter conversion ,photosynthetic process ,shading ,ornamental plants ,Biotechnology ,TP248.13-248.65 - Abstract
Abstract This study aimed to assess the effect of red, pearl and aluminet shading nets on the photosynthetic efficiency of Capsicum chinense and C. frutescens. The experiment was carried in entirely randomized block design. C. chinense and C. frutescens were cultivated under red, pearl and aluminet with 35% shading and direct sunlight as control for 150 days. Leaf area, area duration and area ratio; specific leaf area and harvest index were higher in C. frutescens. Net CO2 assimilation and stomatal conductance were higher in C. frutescens cultivated under red net and C. chinense cultivated under aluminet net. Transpiration was higher in C. chinense cultivated under the aluminet net. Water use efficiency and relative chlorophyll content and intrinsic water use efficiency were higher in C. frutescens cultivated under the red net. Initial and maximum chlorophyll were also higher in C. frutescens cultivated under red net. Maximum quantum efficiency and chlorophyll fluorescence rate decrease were lower in C. chinense cultivated under red net. Linear flux electron was lower in C. chinense cultivated in the control. PSII open centers fraction was higher in control, pearl net for C. frutescens. Non-photochemical extinction coefficient and dissipation of absorbed light were higher in C. chinense cultivated under red net. C. frutescens cultivated under red net had higher photosynthetic efficiency, considering water use efficiency in dry matter conversion and several mechanisms to maximize the photosynthetic process under shaded conditions.
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- 2024
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29. Stepwise Mathematical Modeling, Simulation of Photovoltaic Solar Module/Array Using MATLAB/Simulink and Study of the Effects of Partial Shading on PV Array
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Kamboj, Sandeep, Sambariya, D. K., Kacprzyk, Janusz, Series Editor, Gomide, Fernando, Advisory Editor, Kaynak, Okyay, Advisory Editor, Liu, Derong, Advisory Editor, Pedrycz, Witold, Advisory Editor, Polycarpou, Marios M., Advisory Editor, Rudas, Imre J., Advisory Editor, Wang, Jun, Advisory Editor, Das, Swagatam, editor, Saha, Snehanshu, editor, Coello, Carlos A. Coello, editor, Rathore, Hemant, editor, and Bansal, Jagdish Chand, editor
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- 2024
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30. Modeling Shading and Inter-building Longwave Radiative Exchanges: Comparative Study Using BESTEST Case
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Ach-chakhar, Manal, Guernouti, Sihem, Romani, Zaid, M’Saouri EI Bat, Adnane, Draoui, Abdeslam, Chaari, Fakher, Series Editor, Gherardini, Francesco, Series Editor, Ivanov, Vitalii, Series Editor, Haddar, Mohamed, Series Editor, Cavas-Martínez, Francisco, Editorial Board Member, di Mare, Francesca, Editorial Board Member, Kwon, Young W., Editorial Board Member, Trojanowska, Justyna, Editorial Board Member, Xu, Jinyang, Editorial Board Member, Ali-Toudert, Fazia, editor, Draoui, Abdeslam, editor, Halouani, Kamel, editor, Hasnaoui, Mohammed, editor, Jemni, Abdelmajid, editor, and Tadrist, Lounès, editor
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- 2024
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31. The Effect of Shading, Organic Fertilizer( vermicompost ), and Chelated Iron on the Vegetative Growth Characteristics of Gardenia jasmoida
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zainab mustafa
- Subjects
shading ,organic fertilizer ,chelated iron ,gardenia jasmonida ,vegetative growth ,Agriculture - Abstract
The experiment was conducted in a private nursery (Mohammed Nursery) located on Erbil Road in Kirkuk, situated at 44.38°E longitude and 35.58°N latitude. The experiment lasted five months from 01/04/2022 to 01/10/2022 to study the effects of shading with two levels: 0% (under direct sunlight) and 75% (under saran cover), as well as the effect of organic fertilizer (vermicompost) at two levels: 0% and 25%, where the fertilizer was added and mixed with loamy soil. The experiment was conducted using a completely randomized block design. The plants were randomly arranged on the experimental units with three replicates. Duncan's multiple range test was used to compare the means at a probability level of 0.05%.The results indicated that the 75% shading had a significant effect on some characteristics, such as plant height, dry leaf weight, and leaf area, which reached (82.27 cm), (12.14 g), and (3086.10 cm²) respectively. On the other hand, plants grown under direct sunlight showed a significant increase only in stem diameter (10.69 mm).Regarding the effect of organic fertilization, a significant increase was observed with the use of 25% vermicompost on the following characteristics: plant height (73.55 cm), dry weight (12.63 g), and chlorophyll content in leaves (29.24 CCI).It was also found that the use of chelated iron had a significant effect on most characteristics, where the concentration of 0.2 g.L⁻¹ resulted in the highest significant increase in plant height (75.00 cm), main stem diameter (10.37 mm), dry weight (15.35 g), and chlorophyll content in leaves (29.10 CCI).
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- 2024
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32. 遮阴处理对睡菜 (Menyanthes trifoliata L.) 生长和生理响应的影响.
- Author
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康晓静, 付俊秋, 陈旭, 西战, 施艳霞, and 陈燕
- Abstract
In order to understand the effect of shading on the growth and physiological respond of Menyanthes trifoliata L.and to provide suitable habitat in Beijing area for its protection and utilization. Growth and physiological index of M.trifoliata during different periods were studied under four shading treatments, including full sunlight, 50% shading, 75% shading and 90% shading. The microclimatic factors were also monitored under same conditions. The results showed that height growth, rhizome growh and leaf area growth of M.trifoliata under 50%-90% shading treatment for 60 days during summer were significantly higher than those in full sunlight; SPAD and Fv/Fm of M.trifoliata were effectively increased under 50% shading, compared with CK; moderate shading could effectively reduce light intensity, daily maximum temperatures and increase air humidity. In conclusion, 50% shading of M.trifoliata for 60-90 days in summer is the most favorable cultivation method. [ABSTRACT FROM AUTHOR]
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- 2024
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33. Density-dependent facilitation and inhibition between submerged and free-floating plants.
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Szabó, Sándor, Csizmár, Aliz, Koleszár, Gergő, Oláh, Viktor, Birk, Sebastian, and Peeters, Edwin T. H. M.
- Subjects
- *
POTAMOGETON , *ALGAL growth , *PLANT spacing , *PLANT growth , *GROUND cover plants , *FIELD research - Abstract
This study aimed at testing the hypothesis that free-floating plants may facilitate the growth of submerged plants under hypertrophic conditions and intermediate plant density. The effects of Lemna presence on the growth of two submerged plants (Elodea nuttallii and Ceratophyllum demersum) over a nitrogen gradient were experimentally investigated. This was complemented with analysing the presence of C. demersum and E. nuttallii in Hungary and in Germany in relation to the density of free-floating plants. Results showed a negative exponential pattern between underwater light intensity and Lemna cover. Ceratophyllum and Elodea relative growth rate decreased with increasing nitrogen concentrations and additional low Lemna density stimulated Ceratophyllum and suppressed Elodea. Elodea decreased linearly with Lemna density while Ceratophyllum showed a unimodal response. Total algal biomass (epiphytic and planktonic) was higher in Ceratophyllum than in Elodea treatments and decreased rapidly with increasing Lemna density. The field studies showed a positive relationship between Ceratophyllum and a negative one between Elodea and free-floating plant cover. This study clearly showed that free-floating plants can have either facilitating or inhibiting impact on the growth of submerged plants depending on cover density and macrophyte species. The facilitating effect on Ceratophyllum is most likely due to suppressing epiphytic algal growth. [ABSTRACT FROM AUTHOR]
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- 2024
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34. Diseminasi Optimalisasi Lahan melalui Budidaya Sayuran-Ikan Secara 3- in-1 di Lahan Perkotaan.
- Author
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Lakitan, Benyamin, Rizar, Fitra Fadhilah, Muda, Strayker Ali, Nurshanti, Dora Fatma, Ria, Rofiqoh Purnama, Gustiar, Fitra, Fadilah, Lya Nailatul, Wijaya, Andi, and Aidilfitri, Siti Nurul
- Abstract
The 3-in-1 vegetable-fish cultivation is an innovative cultivation system that integrates floating and climbing vegetable cultivation with fish culture. This cultivation is a solution to the problem of narrow land in urban areas for vegetable-fish cultivation to create: a) Fish farming in a concrete pool at the bottom position, b) Shadetolerant vegetables cultivated using a floating culture system, and c) Climbing vegetables on a dedicated nettedframes as high as 2 meters above the pool. The dimensions of the pool correspond to the available land. The floating raft was constructed using 69 units of 1.5 L plastic bottles as floaters, assembled into a raft with a surface area of 2 m². The buoyancy capacity of the raft is 120 kg. The raft has been patented with Granted patent No. IDP 000065141. The community service activities are a) Open demonstrations for 3-in-1 vegetable-fish farming installations; b) Socialization and assistance to communities interested in implementing it; and c) Collection of data and information for evaluation and publication materials. Static demonstration activities during one cycle of cultivation and socialization to three potential community groups, namely: a) Urban communities as the primary target; b) Journalists for more enlarging coverage of the dissemination; and c) Agricultural students for the learning process. Urban communities can adopt the dissemination of land optimization through 3-in-1 vegetable-fish cultivation on urban land. Community interest in this cultivation system innovation is outstanding, as represented by the community's enthusiasm for this program. [ABSTRACT FROM AUTHOR]
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- 2024
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35. Assessing the combined effect of PV panels' shading and cool materials on building energy loads in different climates.
- Author
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Vakilinezhad, Roza and Ziaee, Navid
- Subjects
RADIANT heating ,ENERGY consumption of buildings ,THERMOPHYSICAL properties ,CITIES & towns ,ELECTRIC power production ,COOLING loads (Mechanical engineering) ,THERMAL insulation - Abstract
PV panels are vastly used for sustainable electricity generation, while they can also help the environment by improving buildings' energy consumption. The best placement for PV panels installation in buildings with flat roofs is the roof. When placed on a building's roof, PV panels affect the building's energy loads by shading the roof surface. However, the shading effect of PV panels could be different depending on the roof's thermal properties and surface materials. The combined effect of shading caused by PV panels and cool materials could significantly change the roof surface temperature, and the building energy demand. In light of the lack of studies considering this combined effect, the present study aims to evaluate the energy-saving effects of different roof materials covered with solar PV panels for a typical residential building in four cities with different climate conditions in Iran. Applying a simulation tool, Ladybug Tools have been utilized for determining the building energy loads and PV panels' power generation. The obtained results indicate that PV panels significantly affect the cooling load of the building, especially during peak times. The hottest city, Bandar-Abbas, benefits the most, with a maximum saved energy ratio (SER) of 3.4%, while the coldest city, Ardabil, has the least SER, 0.5%. Additionally, in cold and moderate climates, the highest SER occurs for the lowest R-value and solar absorption roof, while for hot climates, the highest SER occurs for the roofs with the highest R-value and the lowest solar absorption. Overall, the shading effect of PV panels becomes more significant when solar absorption is high, and the roof R-value is low. Despite the decrease in cooling energy load, PV panels might increase the heating load. Depending on the climate, this contradictory effect of the roof's thermal properties and PV panels shading should be considered in the design process of buildings. Highlights: Cities with hot-humid and cold climates have the highest and the lowest SER, respectively. PV shading is more significant on roofs with high solar absorption and low R-value. The effect of PV panels on heating load varies based on climate. [ABSTRACT FROM AUTHOR]
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- 2024
- Full Text
- View/download PDF
36. Effect of Shading, Organic Fertilizer (vermicompost), and Chelated Iron on the Vegetative Growth Characteristics of Gardenia jasmoida.
- Author
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Mustafa nuftaji, Zainab kamal and AL- Bakkar, Alaa Hussien A.-Q.
- Subjects
ORGANIC fertilizers ,IRON ,CHLOROPHYLL ,VERMICOMPOSTING ,PROBABILITY theory - Abstract
Copyright of Journal of Kirkuk University for Agricultural Sciences is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
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- 2024
- Full Text
- View/download PDF
37. 不同遮阴处理对 4 种麦冬光合特性的影响.
- Author
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曹 娜, 刘 云, 岳 伟, 孙 南, 孙国栋, and 王 闯
- Abstract
With Liriope spicata, L. graminifolia, L. muscari var.variegata and L. spicata var.prolifera as experimental material, the effects of different shading degrees on the photosynthetic properties of 4 kinds of Ophiopogon japonicus have been studied after 90 d of treatment with dif- ferent shading levels, in order to provide theoretical basis for selecting suitable Ophiopogon japonicus for different lighting environments in gar- dens. The results showed that proper shading could promote the synthesis of photosynthetic pigments. The chlorophyll content of L. spicata and L. graminifolia were the maximum under 25% shading, and the contents were 2.38 and 2.10 mg/g respectively. The chlorophyll content of L. muscari var. variegata and L.spicata var. prolifera were the maximum under 50% shading, and the contents were 1.22 and 1.81 mg/g, respec- tively. The maximum net photosynthetic rate of L. spicata was 11.13 µmol/(m²·s) under 25% shading. The maximum net photosynthetic rate of L. graminifolia, L. muscari var. Variegata and L.spicata var. prolifera were 6.15, 6.82 and 8.01 µmol/(m²·s) under 50% shading respective- ly. All factors considered, the optimal shading degree of Liriope spicata was 25% shading. The optimal shading degree of L.graminifolia was be- tween 25%-50% shading. The optimal shading degree of L. muscari var.variegata and L.spicata var.prolifera were 50% shading. [ABSTRACT FROM AUTHOR]
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- 2024
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38. Analysing the Effects of Thin Object Shading on PV Sources: A Dual Approach Combining Outdoor and Laboratory Solar Simulator Experimentation.
- Author
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Axisa, Matthew, Demicoli, Marija, and Mule'Stagno, Luciano
- Subjects
- *
ENERGY harvesting , *LABORATORIES , *PHOTOVOLTAIC power systems - Abstract
The impact of shading has been a prominent subject of discourse within the realm of photovoltaic (PV) energy harvesting and is recognized as a significant detriment to the system's overall efficiency. Nevertheless, prevailing investigations, which predominantly focus on the hard shading originating from building structures and vegetation, singularly address the umbra shadow phenomenon while overlooking the complexity of shadow properties and their varying intensities. In this context, this present research aims to analyze the impact of shading caused by thin objects, wherein shadow formation deviates from a singular-intensity umbra to a blend of umbra and penumbra, exhibiting diverse intensities. In the initial experimental approach, outdoor trials produced statistically significant findings, identifying both the distance and thickness of shading objects as primary determinants influencing the impact of thin object shading on the power output of PV systems. Furthermore, the analysis of the results revealed that under the specified parameters and assumptions, when considering a thin object with a thickness-to-distance ratio of 2.3 mm/225 cm, the resulting power loss of 1.65% is statistically insignificant. Remarkably, laboratory investigations unveiled a notable correlation between penumbra and power loss, contrasting with outdoor experimentation results. The findings highlight the distinction between indoor and outdoor methodologies, stemming from discrepancies in shadow formation characteristics, thereby emphasizing the necessity of acknowledging and comprehending these variations. [ABSTRACT FROM AUTHOR]
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- 2024
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39. The Influence of Shade on the Growth and Production of Butterfly Pea Plants (Clitoria ternatea L.).
- Author
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Asnur, Paranita, Kalsum, Ummu, Kanny, Putri Irene, and Yuliani, Siska
- Subjects
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CENTROSEMA , *MEDICINAL plants , *PLANT growth , *EFFECT of shade on plants , *PLANT yields - Abstract
Butterfly pea (Clitoria ternatea L.) is a medicinal plant known for its anthocyanin pigment content, which imparts a blue color to its flowers. This study aimed to evaluate the influence of shading on butterfly pea flower growth and production. The research design utilized a randomized complete block design (RCBD) for shading treatments. We replicated each treatment level four times, resulting in 20 experimental units, each containing four plants, for a total population of 80 plants. We conducted the experiment at the Experimental Garden of Gunadarma University Campus F7, implementing shade nets at different intensity levels (55%, 65%, 75%, and 85%), along with a control treatment without shading. We made observations on various plant growth parameters such as leaf count, plant length, days to first flower appearance, flower count, fresh weight, and dry weight. The results indicated that shading significantly influenced butterfly pea plants' growth. Plants without shading tended to exhibit better growth in several parameters, such as increased leaf count, higher plant length, and earlier days to first flower appearance. These findings underscore the importance of sunlight in supporting the growth and production of butterfly pea plants. Therefore, careful consideration of shade management is essential in agricultural practices to ensure optimal growth and maximum yield from butterfly pea plants. [ABSTRACT FROM AUTHOR]
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- 2024
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40. Farklı Gölgelendirme Uygulamalarının Domates Bitkisinde Verim, Kalite ve Antioksidan Açısından Tepkisi.
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KARTAL, Adnan, AKHOUNDNEJAD, Yelderem, DAŞGAN, Hayriye Yıldız, TEMUR, Baki, and ERSOY, Lale
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Copyright of Journal of Agriculture & Nature / Kahramanmaraş Sütçü İmam Üniversitesi Tarım & Doğa Dergisi is the property of Kahramanmaras Sutcu Imam Universitesi and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
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- 2024
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41. Effect of Visible Light Blocking Ratio, Irrigation Intervals and Free Amino Acids on Vegetative Growth Parameters of Chrysanthemum.
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Bdewi, Mawj M. and Kadhim, Ahmed A.
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CHRYSANTHEMUMS ,AMINO acids ,PLANT growth ,IRRIGATION ,HUMIDITY - Abstract
Objectives: An experiment was conducted under plastic shades set up for this purpose in the Mashroo Almussaib area (45 km north of Babil Province) to improve vegetative growth indicators for chrysanthemum plants Minngopher cultivar with red flowers. Methods: Use 3 factors in the experiment include the first factor different percentages of visible light blocking (50 and 75) %, The second factor treating plants with three Irrigation Intervals (daily, every 24 hours, and every 48 hours) as for the third factor spraying plants with several concentrations of free amino acids (0,1, 1.50 and 2.00) mg L
-1 . The experiment design in a (2x3x4) factorial design using a R.C.B.D. with three replicates per treatment. Each replicate contained three pots, each with one plant. The results: Showed the study factors have significant impact of the studied parameters, the interaction (75% shading, daily irrigation, and 150 mg L-1 ) give significant impact in the number of leaves (129.0 leave) and the length of the vegetative branch (15.33 cm) while achieved the triple treatment (75% shading, daily irrigation, and 200 mg L-1 ) significant impact in number of vegetative branches (7.67 vegetative branches) and the main stem diameter (6.76 mm), as for the height of the plant, the interactions treatment was impact (75% shading, daily irrigation, and 100 mg L-1 ). Conclusions: From here we conclude that shading ratios play an important role in reducing the impact of stress intensity humidity and thermal associated with treating plants with free amino acids spraying on vegetative plant. [ABSTRACT FROM AUTHOR]- Published
- 2024
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42. From Oasis to Desert: The Struggle of Urban Green Spaces Amid Heatwaves and Water Scarcity.
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Scharfstädt, Lennart, Schöneberger, Peer, Simon, Helge, Sinsel, Tim, Nahtz, Tim, and Bruse, Michael
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In the summer of 2022, an intense heatwave swept through Northern Europe, with London bearing a significant impact. While nature-based solutions are often considered to be ideal responses to such heatwaves, experiences from the 2022 heatwave and others revealed potential drawbacks, particularly for urban green spaces. Prolonged dry spells, frequently accompanying heatwaves, result in excessively dry soil and the subsequent decline of vegetation in large parks. In the present study, microclimate simulations were conducted for Hyde Park in London, a location that experienced such drought during the 2022 heatwave, to examine its microclimatic performance in terms of thermal comfort and tree health. In alignment with the observations, ENVI-met could replicate the lack of noticeable cooling effects during the daytime and only marginal cooling during the nighttime. To address these challenges, mitigation scenarios were explored, incorporating heat mitigation measures such as part-time irrigation, temporary sun sails, and façade greenery. The findings demonstrated that implementing these measures could reduce heat stress by up to 13 K PET (physiologically equivalent temperature). These practical solutions emerged as effective remedies for mitigating the impact of heatwaves on urban green spaces and, hence, improving future urban development overall. [ABSTRACT FROM AUTHOR]
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- 2024
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43. Intermittent shading can moderate coral bleaching on shallow reefs.
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Butcherine, Peter, Tagliafico, Alejandro, Ellis, Sophia L., Kelaher, Brendan P., Hendrickson, Conor, and Harrison, Daniel
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CORAL bleaching ,SOLAR radiation management ,MARINE resources conservation ,CORAL declines ,CORAL reef conservation ,THERMAL stresses ,ECOSYSTEM management ,WATER temperature - Abstract
The health of coral reefs is declining from the effects of human activity and climate change. Mass coral bleaching is often triggered by elevated water temperature and excessive solar irradiance. Shading can reduce coral bleaching risk. Shading-based management interventions, such as whole-ofreef marine fogging, have been proposed as a conservation tool for periods when coral undergoes excessive thermal stress. This study examined the effect of intermittent shade (30% for 0, 4, or 24 h) on two coral species, Duncanopsammia axifuga and Turbinaria reniformis, held at either 26.4°C or 32.4°C for 18 days. Coral fragments were assessed for bleaching (relative mean intensity of grey, chlorophyll a, and symbiont density), photochemistry (PAM fluorometry), and antioxidant biomarkers (SOD and CAT). Shading responses were species-specific, with T. reniformis more responsive to shading than D. axifuga. Thirty per cent shading delayed bleaching up to three-degree heat weeks (DHW), and 24 h shade was more protective than 4 h shade. Shading suppressed catalase activity in T. reniformis. Overall, our results suggest that intermittently shading corals for 4 h can moderate light stress and slow bleaching in some corals and could improve the efficiency of active solar radiation management in marine ecosystems. [ABSTRACT FROM AUTHOR]
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- 2024
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44. Investigation of the Relationship between Shaded Cell Temperature and the Operating Point of PV Systems.
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Smara, Zoubeyr and Aissat, Abdelkader
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THERMAL stresses ,OPEN-circuit voltage ,SOLAR cells ,PHOTOVOLTAIC power systems ,SHORT circuits ,MAXIMUM power point trackers ,BUILDING-integrated photovoltaic systems - Abstract
The building integrated photovoltaic applications (BIPV) are mostly affected by partial shading, which results in a significant decrease in energy efficiency and leads to the apparition of multiple power peaks on the I-V characteristic curve of photovoltaic generators. In mitigating this problem, sophisticated maximum power point tracking techniques (MPPT) are used to track the global peak among the other locals. These techniques do not take into account the overheating of the shaded cells given that, under some critical situations, shaded cell performances may degrade, thus affecting the lifespan of the photovoltaic modules. In this regard, the present work aims to investigate in which peak on the I-V characteristic curve the PV module should operate appropriately with less overheating risk. For that, the shaded cells' temperatures and currents at different operating points were monitored. The results show that the worst-case scenario occurs for small shadow ratios (in the studied case, the shadow ratio 'sr' = 25%) where the temperature of the shaded cell reached approximately three times (300%) the temperature of non-shaded cells. This temperature decreases as the operating point is moved from the short circuit current towards the open-circuit voltage; as a result, the PV module works safely with minimum thermal stress for the maximum power peak near the open-circuit voltage. [ABSTRACT FROM AUTHOR]
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- 2024
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45. The provision of water and shade but not soil amendments in degraded habitats increases the seedling survival of woody species in restoration processes of the Chilean sclerophyllous forest.
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Becerra, Pablo I., Arellano, Eduardo C., Vilagrosa, Alberto, Hernández, Gabriel, and Figueroa, César
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Key message: Using artificial shading in reforested seedlings is recommended for different species, irrigation levels and soil treatments in semiarid ecosystems, but the application of pork sludge and horse guano are ineffective. Application of irrigation, artificial shade and soil amendments can increase the survival of seedlings in plant restoration processes of semiarid ecosystems, however, the effects of shade and soil amendment could occur only without or with low levels of irrigation. In this study, we tested these hypotheses in four woody species (Quillaja saponaria, Lithrea caustica, Schinus polygamus, and Colliguaja odorifera) from the Mediterranean-type climate region of Chile. By mean a factorial experiment, we evaluated different irrigation frequencies (1 L/week and 1 L/2 weeks during the five driest months, no irrigation), artificial shade types (polypropylene shelter, black mesh, deep hole, and no shade) and soil amendment types (natural soil, pork sludge, and horse guano). In 2014, a total of 720 plants per species were planted at each of two sites located in a pre-Andean and a coastal area, and monitored until September 2016. The effect of the type of artificial shade did not depend on the level of irrigation. All shade treatments produced positive effects on the survival of all the species, but the mesh and polypropylene shelter had a greater positive impact than planting in a deep hole. Irrigation treatments increased the survival of all species, although the effect of the highest frequency depended on the site and species. The soil amendment treatments did not have significant positive effects under any condition. In conclusion, the use of artificial shading may be recommended for different species, sites, irrigation and soil treatments in semiarid ecosystems, although the type of shade may depend on the species. [ABSTRACT FROM AUTHOR]
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- 2024
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46. Silvopastoral system with high-density of trees accelerates degradation of tropical grass
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Alyce Monteiro, Fagner Junior Gomes, Lucas Gimenes Mota, Luiz Jardel Müller Motta, Lívia Vieira de Barros, Felipe Gomes da Silva, Carla Heloísa Avelino Cabral, and Carlos Eduardo Avelino Cabral
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forest ,integration ,shading ,Aquaculture. Fisheries. Angling ,SH1-691 ,Animal culture ,SF1-1100 - Abstract
ABSTRACT Tree density is an important aspect in silvopastoral system (SPS) planning, since low luminosity can limit forage perenniality, especially for tropical forages of C4 metabolism. The objective with this study was to verify if an SPS with high tree density accelerates the pasture degradation process and changes the forage chemical composition. The experiment was carried out by comparison of marandu palisade grass [Urochloa brizantha (Hochst. ex A. Rich.) R. D. Webster] pasture in two systems: silvopastoral and open pasture. In the SPS, teak (Tectona grandis) was planted with a density of 750 trees ha-1. Evaluations were carried out over three years (2015, 2016 and 2017). SPS shading reduced herbage mass, tiller density and soil cover over the years. In the marandu palisade grass in the SPS there was a greater stem proportion, which favoured lesser potential digestible dry matter in the first year. Even with a higher amount of stem, higher crude protein concentration and minerals were observed in the SPS. Due to the high density of trees, excessive shading accelerated the process of degradation of the pasture, which demonstrates that planning of the spatial arrangement of tree species is crucial.
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- 2024
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47. Chlorophyll fluorescence, physiology, and yield of winter wheat under different irrigation and shade durations during the grain-filling stage
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Muhammad Asad Naseer, Sadam Hussain, Ahmed Mukhtar, Qian Rui, Guo Ru, Haseeb Ahmad, Zhi Qin Zhang, Li Bo Shi, Muhammad Shoaib Asad, Xiaoli Chen, Xun Bo Zhou, and Xiaolong Ren
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winter wheat ,grain-filling ,shading ,drought ,photochemistry ,photosynthesis ,Plant culture ,SB1-1110 - Abstract
The uneven spatial and temporal distribution of light resources and water scarcity during the grain-filling stage pose significant challenges for sustainable crop production, particularly in the arid areas of the Loess Plateau in Northwest China. This study aims to investigate the combined effects of drought and shading stress on winter wheat growth and its physio-biochemical and antioxidative responses. Wheat plants were subjected to different drought levels— full irrigation (I100), 75% of full irrigation (I75), 50% of full irrigation (I50), and 25% of full irrigation (I25), and shading treatments — 12, 9, 6, 3 and 0 days (SD12, SD9, SD6, SD3, and CK, respectively) during the grain-filling stage. The effects of drought and shading treatments reduced yield in descending order, with the most significant reductions observed in the SD12 and I25 treatments. These treatments decreased grain yield, spikes per plant, 1000-grain weight, and spikelets per spike by 160.67%, 248.13%, 28.22%, and 179.55%, respectively, compared to the CK. Furthermore, MDA content and antioxidant enzyme activities exhibited an ascending trend with reduced irrigation and longer shading durations. The highest values were recorded in the I75 and SD12 treatments, which increased MDA, SOD, POD, and CAT activities by 65.22, 66.79, 65.07 and 58.38%, respectively, compared to the CK. The Pn, E, Gs, and iCO2 exhibited a decreasing trend (318.14, 521.09, 908.77, and 90.85%) with increasing shading duration and decreasing irrigation amount. Drought and shading treatments damage leaf chlorophyll fluorescence, decreasing yield and related physiological and biochemical attributes.
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- 2024
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48. Pre-defoliation canopy height for signal grass ‘Basilisk’ in silvopastoral systems
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Victor Augustus Vasconcelos de Oliveira, Rafael Bolina da Silva, Anielede Cássia Rodrigues Veloso, Matheus Almeida Alves, Marinalva Martins dos Santos, Rodrigo Augusto Cortez Passetti, Lívia Vieira de Barros, Mário Henrique França Mourthé, Manoel Eduardo Rozalino Santos, and Thiago Gomes dos Santos Braz
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Canopy structure ,Chemical composition ,Forage production ,Shading ,Urochloa decumbens. ,Agriculture (General) ,S1-972 - Abstract
The objective of this study was to compare the response of Urochloa decumbens cv. Basilisk pastures in monoculture and silvopastoral systems (SPS), and to determine the most suitable pre-defoliation canopy height for managing this species in SPS. Four pre-defoliation canopy heights (20, 30, 40, and 50 cm) were tested for signal grass in SPS, alongside a control treatment involving defoliation at 20 cm in full sun. The experiment was conducted using a randomized block design with four replicates. The forage accumulation rate was higher in monoculture (36.5 kg ha-1 day-1 of DM) compared to the silvopastoral system (22.0 kg ha-1 day-1 of DM), and there was no significant effect of pre-defoliation canopy height within the SPS. The density of tillers in monoculture was comparable to that observed in canopies managed at a height of 50 cm within the SPS. Leaf mass and leaf percentage were maximized at heights of 40 cm and 50 cm, respectively. Neither the cultivation system nor the pre-defoliation canopy heights in the SPS influenced the fiber and protein content. Leaf accumulation and mass were higher in monoculture, but the cultivation system did not affect the chemical composition of the forage. Heights between 40 cm and 50 cm in the SPS should be used to maximize tillering, mass, and leaf percentage of signal grass ‘Basilisk’. The chemical composition of the produced forage did not undergo significant changes, neither between systems nor across pre-defoliation heights.
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- 2024
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49. Optimizing Outdoor Thermal Comfort for Educational Buildings: Case Study in the City of Riyadh
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Jamil Binabid, Abdulrahman Alymani, and Ammar Alammar
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outdoor thermal comfort ,educational building ,simulation ,optimization ,shading ,passive solutions ,Building construction ,TH1-9745 - Abstract
In hot, arid climates, educational buildings often face the challenge of limited outdoor space usage. This research, through comprehensive simulation, aims to propose practical solutions to enhance outdoor thermal comfort, particularly during school break times and student dismissal periods, thereby fostering more comfortable and functional outdoor school environments. That will happen through achieving the main objective of the study, which is evaluating the suggested passive strategies. Riyadh was selected as the case study, and four representative schools were analyzed through simulation and optimization processes to identify key areas for improvement. The research leveraged simulation tools such as Ladybug and Grasshopper in Rhino, highlighting the practicality and impact of this approach. Simulations were performed to assess the existing outdoor thermal conditions using the universal thermal climate index (UTCI) and to pinpoint regions with elevated thermal discomfort. Passive design interventions, such as shading devices and vegetation, were explored and optimized using the Galapagos in Grasshopper. This methodology supports the originality of this research in its integration of simulation tools, such as Ladybug and Grasshopper, with optimization techniques using the Galapagos plugin, specifically applied to the unique site-specific context of educational outdoor environments in a hot, dry climate in Riyadh. Additionally, insights for urban planners and architects demonstrate the possibility of integrating passive design principles to improve the usability and sustainability of outdoor spaces. The findings indicated that fewer apertures in shade devices combined with greater tree canopies might double the effectivity in lowering UTCI values, thereby enhancing thermal comfort, especially during peak summer months.
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- 2024
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50. Developing Guidelines for Azolla microphylla Production as Compost for Sustainable Agriculture
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Ornprapa Thepsilvisut, Nuengruethai Srikan, Preuk Chutimanukul, Rusama Marubodee, and Hiroshi Ehara
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Azolla ,manure ,shading ,nutrient content ,fresh biomass yield ,Science - Abstract
Azolla is a substitute compost that has the potential to enhance nutrient cycling in agricultural systems for sustainable development. In this study, four experiments were conducted to compare the Department of Agriculture (DOA, Thailand)’s methodology for determining the suitable type and rate of animal manure and the optimal light intensity for the growth and yield of Azolla (Azolla microphylla). The results revealed that applying 100% pig manure gave the highest yield of Azolla compared to the other manures. However, there was no discernible (p > 0.05) difference in yield across the various doses (20.16, 30.16, and 40.16 gN m−2) of pig manure treatments, for which the minimal pig manure dosage of 20.16 gN m−2 was chosen. For further experimentation in the optimal light intensity, the 40% shading gave the highest yield of Azolla compared to no shading or 20 and 60% shading (p ≤ 0.01). When compared with the DOA Thailand methodology (1.27 kg m−2 of cow manure and covered with a size 32 mesh net), the findings indicated that the modified method (20.16 gN m−2 of pig manure + 40% shading) gave a 16% greater Azolla yield than that under the DOA Thailand methodology. The current finding method can produce a monthly fresh biomass of A. microphylla of 40.7 t ha−1 year−1 with higher contents of total N (4.92%) and lower C:N ratio (≤10:1) that could release minerals relatively rapidly. Its use can be encouraged by farmers to produce their own ecofriendly biofertilizer or soil amendment for sustainable agriculture.
- Published
- 2024
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