Shade Type Research Articles

The Effect of Soil Amendments and Shading on the Yield of Red Chili (Capsicum annum L.) in a Sandy Dryland

Low nutrient along with intense sunlight levels in sandy drylands, often lead to poor crops yield. This study examined the effects of soil amendments and shading on the yield of red chili plants cultivated in a sandy (70% sand, 15% clay and 15% silt) dryland environment. The experiment was conducted in Gumantar Village, North Lombok Regency from May to September 2024. The C-organic content of the soil was 1.11% with only 0.09% of total nitrogen. The soil amendment treatments included no soil amendment, chicken manure, and seaweed biochar. The shading treatments consisted of two levels: no shading and shading using a 200-micron UV plastic with 14% diffusive ultraviolet ray. All treatments were arranged factorially using a randomized block design with three replications. The results indicated that soil amendments and shading did not significantly affect plant growth, certain soil chemical properties, or microbial populations, possibly due to its short time effect. However, both types of soil amendments and UV plastic shading increased the yield of red chili plants by approximately 6.0% compared to the treatment without any amendments or without shading. This study shows that soil amendment and shading with UV plastic improve tomato yield in sandy dryland soils.

A novel mathematical control algorithm (HNU Shading) for different window shades based on HNU solar model

Window shading control helps maximize daylight use for creating comfortable indoor luminous environments and reduces over-illuminance and glare discomfort. This study proposes a novel mathematical algorithm (the HNU Shading algorithm) for calculating the distribution of direct sunlight indoors and adjusting window shades to avoid over-illuminance and glare indoors. The algorithm uses the sun position, window-ambient illuminance, window design parameters, and the controlled area (desktop and occupant’s head) as inputs to control different window shades (the vertical blind, horizontal blind, exterior awning, and interior shutter in this study), and the performance was verified via experiments and simulations. The results show that the HNU Shading algorithm has a high precision level of predicting the distribution area of direct sunlight with the error at 0.01–0.07 m. And it prevents the high illuminance from the desktop and keeps it lower than 3,000 lx under most of conditions with different window directions, shade types, seasons, and sunlight intensities. Meanwhile, with the HNU Shading algorithm, the Daylight Glare Probability (DGP) is lower than 0.4 during the period when intolerable glare happens. This study contributes to configuring practical and universal real-time window shading controls for different buildings with different window shade types, such as offices, classrooms, libraries, airports, and railway stations.

Impact of tent shade on heat exposures and simulated heat strain for people experiencing homelessness.

Concurrent increases in homelessness and heat intensity, duration, and frequency translate to an urban heat risk trap for the unsheltered population. Homelessness is both a driver and consequence of poor health, co-creating distinct geographies with various risk factors that exacerbate heat vulnerability. We tested the efficacy of different tent shadings over identical tents often observed in the Phoenix area (white bedsheet, mylar, tarp, and aluminum foil) and compared them to a control tent (uncovered) and ambient conditions. We monitored all meteorological variables at all six locations, notably Mean Radiant Temperature (MRT). The in-tent microclimate variability was applied to complete statistical and physiological modeling including substance use on heat strain. Findings indicate that tent shadings resulted in significantly lower in-tent MRT during the day (p < 0.05), but exacerbated in-tent thermal risk during the night compared to the control tent and ambient conditions. Furthermore, we found evidence that the temperature metric matters, and using only either MRT or air temperature (Tair) to assess "heat" could lead to inconsistent conclusions about in-tent microclimate. Interactions between shade types and time significantly amplified in-tent thermal risk. Physiological modeling indicates a higher risk of heat strain (core temperature beyond 40˚C) for people using substances. Decision makers should promote testing different heat intervening strategies toward realizing effective means of protecting human life and preventing heat illnesses. This study illuminates the need for an interdisciplinary approach to studying tents as shelters that considers the total heat load with heat strain modeling.

Characterisation of view relative to solar-control systems

Solar shading can be an effective way of avoiding overheating by reducing solar gains in buildings. However, solar shading systems can block or obscure the view-out with the consequence that occupants may refrain from using the shading system. As such, there is a need to quantify the effects of shading on occupants’ perception of the view.In this study, we developed a method to identify the photometric parameters and compositions that are effective in characterising the view-out in relation to different solar-control systems. We hypothesized that the photometric composition, e.g., contrast, in the visual environment as a result of using solar-control systems impacts the subjective assessment of the view. We conducted objective photometric measurements using calibrated luminance cameras and subjective responses from 64 participants in a semi-controlled work environment to test the hypotheses. The participants were randomly allocated to a combination of five view-outs and six solar shading systems in a work environment where they answered questions related to the indoor environment and view quality. The relation between view and solar-control systems and their impact on the subjective view assessment was tested using linear mixed-effects models. The models were developed using forward and backward selection based on AIC and likelihood ratio tests (LRT) to test the effects of adding or removing variables. The achromatic contrast calculated based on the measured luminance data both locally and globally was significantly associated with view assessment and satisfaction when using different shading types.

Effects of heat stress mitigation strategies on feedlot cattle performance, environmental, and economic outcomes in a hot climate

The increase in average global temperatures presents a challenge for the beef industry, especially in the feedlot sector where heat stress is a major animal welfare and economic concern. Shade is one of the most practical methods to mitigate heat stress in feedlot cattle. An experiment was conducted as a completely randomized design with 1 560 Bos indicus bulls (initial BW=287 kg) where three shade structure types were used to investigate the effects of different heat stress mitigation methods on cattle growth performance, environmental, and economic outcomes using live animal data, and a partial lifecycle assessment using the Integrated Farm System Model. The live animal portion of the experiment was done once a year over a 2-year period with three pen replications per treatment per year (n = 6 per treatment). Four shade structures used were conventional shade (SC; steel shade 1.8 m2 of shade/animal), double conventional shade (DS; steel shade 3.6 m2 of shade/animal), dome structures without fans (DSA; 8.5 m2/animal with 98% solar radiation blocked), and domes with fans (DCA; DSA plus three large sized low-speed fans). Each pen held 65 bulls in an area of 570 m2. Live animal data were analyzed as a completely randomized design using the GLM procedure of SAS (version 9.4) with shade type as fixed effect, pen as the experimental unit, and repetition (year) considered a random effect. Cattle housed under DCA had 22 and 20 kg heavier final body BW (P < 0.05) compared to those housed under SC and DS, respectively. Final BW of DCA and DSA cattle were similar (P > 0.05). Average daily gain, feed efficiency, and hot carcass weight were greater (P < 0.05) for cattle housed under DCA compared to the rest of the shade types. Dry matter intake was not affected (P > 0.05). When treatment results were extrapolated to the annual feedlot turnover of 209,700 animals, cattle in DSA and DCA versus SC and DS had 3–8% reductions in greenhouse gas and ammonia emission intensities. Compared to SC, DCA increased profitability by $29.66/animal, followed by DSA and DS with profit increases of $5.79 and $8.90/animal, respectively. Overall, the implementation of advanced shade structures improved cattle performance and profitability while reducing the environmental impact of beef production.

High-intensity light promotes adaptive divergence of photosynthetic traits between sun-exposed and shaded populations in Saxifraga fortunei.

Light is essential for plants, and local populations exhibit adaptive photosynthetic traits depending on their habitats. Although plastic responses in morphological and/or physiological characteristics to different light intensities are well known, adaptive divergence with genetic variation remains to be explored. This study focused on Saxifraga fortunei (Saxifragaceae) growing in sun-exposed and shaded habitats. We measured the leaf anatomical structure and photosynthetic rate of plants grown in their natural habitats and in a common greenhouse (high- and low-intensity light experimental sites). To assess differences in ecophysiological tolerance to high-intensity light between the sun and shade types, we evaluated the level of photoinhibition of photosystem II and the leaf mortality rate under high-intensity light conditions. In addition, population genetic analysis was conducted to investigate phylogenetic origins. Clear phenotypic differences were found between the sun and shade types despite their recent phylogenetic origin. The leaf anatomical structure and photosynthetic rate showed plastic changes in response to growing conditions. Moreover, the sun type had a well-developed palisade parenchyma and a higher photosynthetic rate, which were genetically fixed, and a lower level of photoinhibition under high-intensity light. Our findings demonstrate that light intensity is a selective pressure that can rapidly promote phenotypic divergence between the sun and shade types. While phenotypic changes in multiple photosynthetic traits were plastic, genetic divergence in specific traits related to adaptation to high-intensity light would be fundamental for ecotypic divergence to different light regimes.

Shade Selection, a Key to Esthetics

ABSTRACT One of the most difficult steps in restorative dentistry can be precisely matching natural teeth with an artificial restoration. Natural teeth come in a variety of shapes and hues. The type of shade guide, the person’s capacity for shade selection, and the circumstances surrounding the decision-making process all affect how accurate and dependable the process is. As a result, instrumental color determination must be incorporated into routine tasks. Many factors affect color matching, and when done incorrectly, it can lead to outcomes that are not satisfactory for the patient or the clinician. The following article sheds light on various methods of shade selection and which method is superior in matching the shade as close to that of the natural tooth color.

Farmworker-Relevant Heat Exposure in Different Crop and Shade Conditions

ABSTRACT Objectives Agricultural workers are at risk of heat-related illness, which is preventable. Few field studies have compared farmworker-relevant heat exposure in different conditions. We examined heat exposure over time in different potential shade and work locations to inform future occupational heat prevention approaches. Methods We assessed heat exposure in Eastern Washington State (WA) cherry and grape fields in August 2022. QUESTemp° monitors recorded Wet Bulb Globe Temperature (WBGT) and Black Globe Temperature (BGT) every 10 min from approximately 07:00–14:00 for three days in the center of crop rows (mid-row), under portable shade structures (shade), and in open field (open) locations. Linear mixed effects regression (LMER) models compared WBGT and BGT among field locations. Hourly time-weighted average WBGT and comparisons with occupational exposure limits (OELs) were computed for different hypothetical work-rest cycles during the hottest sampling hours, assuming different worker effort levels, rest locations (mid-row versus shade), and acclimatization statuses. Results Across all crops and locations during the study period, the mean/SD air temperature was 31°C (88°F)/3.9°C (6.9°F), with a maximum temperature of 39°C (102°F) and a mean/SD relative humidity of 30%/9.6%. LMER models suggested no significant difference in mid-row versus open WBGT but significantly lower WBGT in shade versus open locations for both cherries (main effect −5.14: 95% confidence interval [CI] −6.97,−3.32) and grapes (−6.20: 95%CI −7.73,−4.67), though this difference diminished over the course of the day. BGT was significantly higher in the mid-row than the shade (cherries main effect 14.33: 95%CI 9.52,19.13 and grapes 17.10: 95%CI 13.44,20.75). During the hottest sampling hour, the exceedances of OELs were reduced with assumptions of increased shaded break lengths, reduced effort level, and acclimatization. Conclusions Shade canopies, but not the crops studied, provided significant reductions in heat exposure. We observed increased protection from heat assuming longer shaded breaks and reduced effort levels. Results highlight the need for additional field research on the effectiveness, feasibility, and acceptability of different shade types and work-rest cycles to guide employer optimization of best practices for worker protections, including acclimatization before high heat, sufficient shaded rest time, reduced effort levels as the day warms, and avoiding work in peak heat.

Effect of shade tree on nutrient concentration in coffee (Coffea arabica L.) leaves

Abstract Leaf tissue analysis is a measurement of the levels of elements contained in plant leaves. In this case, the leaves can describe the amount of absorption of a nutrient because most of the assimilation results are collected in them. The nutrients that can be absorbed by plant roots are the amount of nutrients available in the soil. The use of shade trees with different types of sunlight absorption intensity causes the conditions for leaf nutrient absorption in plants to also vary. This research was needed to determine the effect of shade type on the nutrient concentration of nitrogen, (N), phosphorus (P), and potassium (K) in the leaves of Arabica coffee plants. This research was carried out at the Koperasi Ribang Gayo Musara, Pantan Musara Village, Pegasing Subdistrict, Central Aceh District, Aceh, and the Agricultural Instrument Standardization Agency (BSIP) Aceh. This research used a non-factorial Randomized Block Design with five treatments where each treatment 4 replications. Treatments consisted of types of shade plants on coffee plants, namely, control/no shade, small lamtoro shade (Leucaena leucocephala ssp. leucocephala), big lamtoro shade (Leucaena leucocephala subsp. glabrata), banana shade (Musa paradisiaca L.), avocado shade (Persea americana Mill.). The results showed that shade tree type significantly affect potassium (K) nutrient levels in coffee plant leaves. Coffee plant shaded by big lamtoro had better N, P and K nutrient levels compared to small lamtoro, banana, avocado, and control.

Agent-based modelling and simulation of elderly residents’ dynamic usage patterns in neighbourhood squares during summer

Understanding how elderly residents use neighbourhood squares is helpful for designing these public areas to maximize their usage and minimize heat exposure risks, especially given the global increase in heatwaves and initiatives for healthy aging in place. This study aims to explore the dynamic use of a neighbourhood square with multiple shade configurations by its elderly residents. In-situ observations and measurements in three squares in public housing estates in Hong Kong were conducted in hot summer days to learn the relationship between elderly users' usage behaviours and multiple driving factors, including outdoor thermal environment, level of social interaction, and different shade types. The relationship was then used to develop an agent-based model (ABM) to simulate the dynamic usage pattern in a square over a day. The result indicates that the dynamic usage pattern from 9:00 to 18:00 in a square emerges from interactions between elderly users’ behaviours and shade configurations, which can be reasonably estimated by the developed ABM. Based on the ABM simulation, shade configurations that cover 60 % of the square and create microclimates with a maximum mPET not exceeding 34.0 °C during summer days encourage square usage and mitigate heat-stress risks of elderly users. The prototype ABM enables the understanding of the complex usage pattern in a neighbourhood square and can potentially assist planning and optimization of shade configurations at the design/renewal stage.

The Efficacy of Horizontal Adjustable Bent Louver Shading for Enhancing Daylighting Performance in Walk-Up Apartment Buildings

This paper addressed the challenges posed by the limited windows and restricted areas in walk-up flats in Indonesia, resulting in improper indoor daylight performance. The study proposes using outdoor horizontally bent, adjustable louver screens as daylight reflectors to overcome this issue and improve daylighting performance in apartment buildings. The quasi-experimental technique implemented the Radiance Desktop Plug-in Version 1.02 and Ecotect 2011 lighting software. Variables, such as slat shading geometry, i.e., flat, one-bent, two-bent slats, and rotation opening angles, i.e., 30°, 45°, 60°, and 90°, were examined for interior daylight performance regarding daylight intensity and distribution. The findings indicate that although shading can reduce the average lighting level in a room, shading types with bents can improve daylight performance in another important aspect, namely achieving a more even distribution. The most effective shading technique for harvesting and distributing daylight evenly in tropical walk-up apartments was a two-bent slat type, particularly with opening angles of 90°. The results also demonstrate that louvers with multiple bent slat geometry are particularly effective in reflecting high altitudes of incident light often encountered in tropical regions and scattering the incoming light evenly into the innermost area of the room.

Overheated children's playgrounds in Central European cities: The effects of surfaces and shading on thermal exposure during hot summer days

Thermal exposure in children's playgrounds is a specific issue in relation to outdoor thermal comfort. In moderate climate regions, playgrounds are prone to overheating on hot summer days. When aiming for a safe design for playgrounds, different thermal conditions with various active surfaces and shading solutions, both natural and artificial, should be considered. Twelve case studies were performed in four Czech cities to quantify the differences in thermal exposure between individual types of active surface and shading, using mean radiant temperature and the biometeorological indices UTCI and PET (plus its experimental child-specific adjustments) as an expression of the thermal environment on hot summer days. The highest thermal exposure appeared above gravel, followed by rubber. Nevertheless, apart from a slightly lower thermal exposure above maintained lawn, substantial positive microclimatic effect of natural surfaces, such as bark mulch, sand, or a small water pool, was not confirmed. In terms of shading, trees provide more pronounced cooling effect than shade sails, but even the latter are effective in substantially reducing heat stress. Analyses of experimental adjustment of PET further indicate the importance of considering the specifics of a child's organism and behavioural adaptation measures when addressing thermal comfort and heat stress in playgrounds.

Study of Shading Types in Heat Transfer Calculation in High-Rise Building

Tall buildings require a lot of energy in their use. The energy needed is mainly for thermal comfort in the buildings. The heat gained by the building comes from solar radiation. Nowadays many tall buildings use translucent materials. This definitely increases the heat gain that enters the building. Shading is used to reduce the heat that hits the translucent facade. Calculations are needed to see the effectiveness of shading. the purpose of this study is to analyze the effectiveness of using shading in OTTV calculations. The method used is a quantitative approach. A quantitative approach is used. The result is that horizontal shading only reduces heat gain by 20 percent. Vertical shading is able to reduce heat gain by 25 percent on the north and south sides. Vertical shading is more effective because it can handle lower angle sunlight. a combination of both shading is needed to be able to get a smaller multiplier number so that the calculation results meet the standards.

Pengaruh Naungan Lentera, Alpukat, dan Sengon Terhadap Kondisi Iklim Mikro Pada Lahan Agroforestri Kopi Robusta

One of the factors that affect the growth and productivity of coffee plants is largely caused by microclimates such as air temperature, air humidity, wind speed and light intensity related to the type of shade used. The purpose of this study is to determine the effect of the use of shade on the growth and productivity of robusta coffee plants. This observation was carried out on the agroforestry coffee plantation land of Wonosalam District. The coffee plants observed were 5 to 7 years old, and the shade used in the observations were lamtoro trees, avocados and sengon trees. While the research design used was a randomized experimental design consisting of control shade and plant shade. Thus, based on the results of observations that have been made for one month, the highest results in the first week were obtained 25.5-26.30C at air temperature. While the highest observed humidity occurs in the first week and fourth week by 71%. The highest wind speed occurs in the third and fourth weeks of 4.8-5.0 km / hour. The highest light intensity produced occurred in the third week of the control shade, which was 37020 LUX. The results of these observations prove that the use of shade plants has no real effect on the production and growth of robusta coffee plants.

Civet latrines in three habitats of a coffee dominated landscape of the Western Ghats biodiversity hotspot

Civets are frugivorous animals in the Order Carnivora. They are relatively less shy towards people and anthropogenic habitats. It has been reported that the civets’ preference of defecating in open sites enable them to be important seed dispersers of degraded forests and urban ecosystems of Asia and Africa. We surveyed for scats of palm civet (Paradoxurus hermaphroditus) in forest fragments of sacred groves (closed), coffee plantations (partly closed) and home gardens (relatively open) during the fruit ripening period of Coffee and Caryota urens – the two preferred fruits of civet – to report the microhabitat characteristics and seed composition of civet latrines. The microhabitat of each scat position – whether on or off the ground and the shade type – was recorded. The scat analysis showed the presence of 4234 seeds belonging to coffee (90.2%), C. urens (9.7%), and an anonymous Rubiacea species (0.10%) in a total of 105 scats collected from coffee plantations (55), home gardens (5), and sacred groves (45). The number of scats sampled from the three habitats was different, but not the number of seeds per scat. Overall, the number of scats increased with the canopy cover, but the trend was different for different habitats. In home garden and coffee plantations, it decreased, but in sacred groves, it increased with the canopy cover. The number of scats sampled above the ground – on tree branches, logs and built-up structures– was more than that was on the ground. The findings contradict the general belief that the civet latrines occur more in open areas than the shaded areas. Because the civet latrines are seen more above ground than on the ground, their efficiency as seed dispersal agent may be examined critically in different contexts.

Shading and Planting Material Type Effects on Some Physiological and Biochemical Compounds Synthesis in Desmodium adscendens Plants Leaves in the Domestication Phase, Daloa, Côte d'Ivoire

Desmodium adscendens (Sw.) is a plant of the Fabaceae Family, a wild medicinal plant frequently found in industrial plantations, where it is exposed to pesticide residues. This makes species unsuitable for use as a raw material in pharmaceutical industry. To this end, domestication is one of best ways of cleaning up the species. During this process, the evaluation of a few physiological and biochemical compounds would be an indicator for the choice of planting material and the ecology species. Two types of plant material (seeds and stem) grown under three types of shade (accentuated, moderate, no shade) were tested. The leaves of various 90-day-old plants were used to determine physiological and biochemical parameters various. Results showed that chlorophyll a, carotenoids, polyphenols, total sugars, protein, proline and the activities of tyrosine ammonia-lyase, polyphenol oxidase and catalase were higher in leaves with moderate and no shading. However, under heavy shading, chlorophyll b content, phenylalanine ammonia lyase (PAL) and peroxidase enzyme activities were higher. Whatever shading type, the chl (a) content remained lower than that of chl (b). Also, total sugars, proline, ascorbate peroxidase and catalase were more abundant in the leaves of plants grown from stem. In contrast, phenolics, proteins and PPO are more abundant in leaves of seedlings.

The performance of natural lighting in classrooms using shading devices

One alternative energy source to replace fossil energy is sunlight. The presence of sunlight has an impact on the building in the form of heat radiation and natural lighting. Under certain circumstances, these two effects are contradictory. Buildings need natural lighting to reduce their reliance on artificial lighting, but adding this natural lighting also causes the building to become warmer, which will increase the energy required for air conditioning. One alternative solution to reduce the intensity of heat entering a building is the use of shading devices. The presence of sun shading is believed could be used to prevent heat radiation from entering the building, but the lighting intensity is not at its best. Educational buildings, particularly classrooms, are one type of building that utilizes natural lighting extensively. One of the educational buildings that has attempted to use shading devices. This research aims to determine the perfomance of natural lighting, especially uniformity in classsrooms that used shading devices. The research administers quantitative methods with Dialux Evo software simulation to determine the uniformity ratio of natural lighting in classrooms that use various forms of shading devices The research results reveal that the performance of classrooms with the four types of shading devices still does not meet standards. There is still a need for adjustments to the four types of shading devices so that their performance can meet standards

A Study of Shading Selection Strategy for Natural Ventilation of Office Buildings in Jakarta

In this post-Covid-19 pandemic, the existence of a space that is connected to outside air circulation is a necessity. This is because good air circulation can reduce the potential for the spread of Covid-19 indoors. One of the challenges in implementing natural ventilation is the entry of excess solar heat into the building. One strategy that can be done to avoid the entry of excess solar heat is to use shadows to filter sunlight. This study examined the appropriate shading strategy that can be applied to overcome the problem of excessive solar heat in the ventilation section of office buildings in Jakarta. The research will be conducted using an experimental method, Sketchup’s Pre-Design simulation. The simulation results show that Eggcrate and Automated Blinds shading are two types that can reduce harmful solar heat entering the building the highest compared to other types of shading.

Impact of shade on outdoor thermal comfort, in the case of a Mediterranean Promenade

Outdoor thermal comfort is a frequent research topic nowadays. This research focuses on the Mediterranean coastal promenade, taking as a case study the coastal promenade of the city of Durres in Albania. The purpose of this research is to find out how and to what extent natural and artificial shades impact outdoor thermal comfort at the pedestrian’s level by including climate parameters during the analysis. The study is both quantitative and qualitative. Following an evaluation of the urban texture, thermal cameras and climatic instruments are used to conduct field measurements. Then, ENVI-met computer simulations are run with a focus on the PET index. The results of measurements and simulations of the promenade have indicated a high level of thermal stress. In the end, using computer simulation, two hypothetical scenarios are developed, taking into consideration the parameter of shade. They are set under identical climate circumstances on a common summer day. The results of the scenarios have shown that selecting the appropriate types of greenery and artificial shading improves pedestrian thermal comfort by 12-45 percent. Thus, it is very important how promenades and public spaces are designed, paying special attention to their physical elements such as natural and artificial shading.

Is there an optimum balance between indoor environment, energy consumption and health?

This study investigates the pros and cons of passive strategies in the indoor environment (IE) in relation to energy consumption (EC). It is widely accepted that IE improvements often require energy, particularly for thermal and atmospheric IE. As a result, demands for energy savings might compromise the indoor environmental comfort and health. However, the energy consumption can be reduced by introducing passive measures both regarding temperature and ventilation rates. To investigate this, measurements of temperature and ventilation rates were carried out in eight newly built single-family homes and four renovated single-family homes in a Danish context for three years. The study analyzes the effect of passive cooling using different types of solar shading. The findings show that external solar shading can effectively reduce high temperatures without additional energy consumption for cooling in a Scandinavian context. Also, the difference between mechanical and natural ventilation on CO2 levels in bedrooms and children’s rooms in relation to sleep quality are analysed. Here the results show, that natural ventilation is insufficient to ensure healthy sleeping conditions when it comes to proper ventilation rates and air quality. Supplemental ventilation by either window airing or mechanical aid is necessary.