Shading Intensity Research Articles

Analysis and experimental validation of partial shading mitigation in photovoltaic system using integrated dc–dc converter with maximum power point tracker

An integrated dc–dc converter with maximum power point tracker (IDCCM) is an electronic device that can be utilised to increase the output power of a photovoltaic generation system. Despite its potential benefits, there is an absence of a comprehensive analytical work to characterise the IDCCM performance under different partial shading conditions. Thus, this work proposes an analytical method to evaluate the system with IDCCM for different shading pattern/intensity, irradiance, and temperature. To validate the analysis, the SPV 1020 boost-type IDCCM devices are incorporated into a 2 kWp experimental test-rig. The performance of the IDCCM is benchmarked against the conventional system that utilises bypass diodes (alone). The results indicate that the IDCCM improves the performance of the central inverter as it ensures the latter consistently tracks the global peak. Also, it was found that that the performance of the IDCCM depends on the shading intensity: at low intensity, the IDCCM is able to extract energy from the shaded modules; however, it is ineffective at high shading intensity. Furthermore, when the shading is absent, the energy gained by the IDCCM is offset by the continuous power losses due to its internal operations.

Banana leaf pruning to facilitate annual legume intercropping as an intensification strategy in the East African highlands

• Increasing banana leaf pruning levels progressively reduced banana performance while increasing legume yields. • Legume intercrops with high biomass (e.g. climbing beans) reduced banana performance. • Land-use efficiency was reduced by severe banana leaf pruning (i.e. retaining 4 leaves) but improved by moderate pruning. • The un-pruned banana monocrops had the highest labor and overall economic efficiency. • The decision to prune or not, to integrate legumes was thus trade-off between agronomic and economic efficiency. Banana leaf pruning is a common practice to facilitate intercropping with legumes on farmers’ fields. It is however not clear if this practice improves farmers land-use and economic efficiency, especially after full canopy formation. To analyze pruning effects, three legumes viz. bush bean ( Phaseolus vulgaris L ), climbing bean ( Phaseolus vulgaris L ) and soybean ( Glycine max ), were planted under three banana leaf pruning levels in which four, seven and all fully grown leaves were retained. Sole banana or legume plots served as controls. Each treatment combination was replicated three times. Banana growth and yield attributes were measured for the plant and first ratoon crops while legume biomass and yields determined over five consecutive cropping seasons. Significant (P < 0.001) reductions in banana growth and yield were associated with leaf pruning. Banana yield reductions of 31% and 10% for the four- and seven-leaf retention treatments, respectively occurred. The vigorous intercrops (climbing beans and soybeans) more often depressed the growth and yield of banana. Legume grain and biomass yields increased with leaf pruning levels. Weed biomass and associated management costs increased with decline in shade intensity. The land-use efficiency measured using the land equivalence ratio (LER) was far lower in the treatment with four-leaves (1.10) compared to when all leaves were retained (1.4) but higher (1.54) for the seven-leaf treatment. Severe banana leaf pruning could thus be detrimental to banana performance and inefficient. Moderate banana leaf pruning could however be promoted were land is limiting and farmers want to maximize diversity/nutrition. However, the highest values for gross revenue and benefit-cost ratio were realized for sole banana-all-leaf retention treatment due to a higher labor productivity and lower input costs attributed to the perennial nature of banana. The higher economic efficiency in sole banana plots suggests that reliance on LER only may be insufficient for guiding intercropping decisions.

Daily Light Integral Requirement of a Creeping Bentgrass Putting Green as Affected by Shade, Trinexapac‐ethyl, and a Plant Colorant

ABSTRACTTurfgrass quality is often limited by the availability of photosynthetically active radiation (PAR) delivered to the turf surface. The cumulative PAR at a given site during 1 d is termed the daily light integral (DLI) and is an effective measurement for quantifying light requirements for various turfgrass systems. The minimum DLI necessary to maintain acceptable quality on creeping bentgrass (Agrostis stolonifera L.) putting greens has yet to be determined. Shade timing, trinexapac‐ethyl growth regulator, and ultraviolet‐absorbing plant colorant applications may affect the DLI requirement of creeping bentgrass putting greens. The objective of this research was to determine the DLI requirement of a creeping bentgrass putting green by evaluating the effects of shade intensity and timing, as well as the influence of trinexapac‐ethyl and a plant colorant on turfgrass quality and coverage. Intensity treatments of 0, 70, 80, and 90% shade were applied during either morning (sunrise to solar noon) or afternoon (solar noon to sunset) hours from May through October 2016 and 2017 on a ‘Tyee’ creeping bentgrass, sand‐based putting green. Evaluations of visual turf quality and turf coverage were performed every 2 wk. After 2 yr, the DLI requirement to maintain acceptable putting green quality was estimated to be 30 mol m−2 d−1. Although effective in improving turf quality at times during summer months, trinexapac‐ethyl and the plant colorant did not significantly reduce the DLI requirement.

Apricot-based agroforestry system in Southern Xinjiang Province of China: influence on yield and quality of intercropping wheat

Agroforestry is a common traditional practice in China, especially in Southern Xinjiang, Northwest China. However, the productivity of many agroforestry systems has been lower than expected in recent years. We chose an apricot (Prunus armeniaca L.)/wheat (Triticum aestivum L.) intercropping system to investigate the influence of apricot tree shade intensity on the grain yield and quality of intercropping wheat in Southern Xinjiang Province. We found that the mean daily light intensity in the east-row, inter-row, and west-row positions (apricot trees were planted in north–south orientation) in the intercropping systems decreased by 61.5%, 42.2%, and 63.6%, respectively, compared to the monoculture wheat. Correspondingly, the mean daily photosynthesis rate decreased by 52.0%, 28.4%, and 38.8%, respectively. The total florets, fertile florets, total spikelets, fertile spikelets, and grain yield and its components (including spike number, grains per spike, and thousand grain weight), and the total N and P contents of intercropping wheat in apricot-based intercropping systems were all significantly decreased compared to monoculture wheat. However, the protein content and wet gluten content of intercropped wheat were significantly increased compared to monoculture wheat. We did not find significant differences in any parameters among east-row, inter-row, and west-row positions in intercropping systems.

PENGARUH INTENSITAS NAUNGAN DAN PEMBERIAN PUPUK ANORGANIK TERHADAP PERTUMBUHAN SEMAI Hopea bancana (Boerl.) Slooten

Hopea bancana (Boerl.) Slooten is an important species of timber-producing trees. This species is endemic to Indonesia and is categorized as threatened plant (critical: Critically Endangered) based on the IUCN Redlist of Threatened Species 1998. Research and development on its silviculture aspects is very important as an effort to support the recovery of species and enrichment of the population in nature. This study aims to determine the effect of shade intensity and application of inorganic fertilizer (NPK) on Hopea bancana 's survival and seedling growth. The study was conducted with factorial complete randomized design consisting of 2 factors, namely: shade factor with 2 levels (50% and 75%) and inorganic fertilizer with 4 levels (0 gr, 3, gr, 4 gr, and 5 gr), so that 8 combinations of treatments were obtained. The survival rate was analyzed descriptively. Growth variables which included growth in height, number of leaves, leaf length, and root length were analyzed by analysis of variance (ANOVA). The results showed that the shade intensity of 50% gave better results in the survival rate of the seedlings. Shade intensities and inorganic fertilizer factors showed very significant differences in plant growth and root length. The best results of growth parameters of plant height, leaf number, and leaf length were indicated by N350 treatment (NPK fertilizer 3 gr, 50% shade intensity), while root length was indicated by N050 (NPK fertilizer 0 gr, shade intensity 50%). Treatment of NPK 3 gr at 50% shade intensity tends to show the best results in the character of seedling growth.

Subcell Modeling of Partially Shaded Photovoltaic Modules

Increased photovoltaic installations in densely built-up areas give rise to non-uniform irradiation causing partial shading. Non-uniform irradiation further leads to non-uniform temperature, leading to a reduction in output and the formation of deteriorating hotspots. A detailed model involving subcell level behavior is pivotal in understanding the impact of partial shading. In this paper, such a model is developed that analyzes the output of photovoltaic (PV) modules under different translucent and opaque shades while incorporating the diffused light effects. This model further includes the temperature variation of the module and also captures the bypass diode characteristics. The proposed model is experimentally validated for horizontal, vertical, slant, and patch shading patterns with varying shading intensities. This subcell model is shown to perform better than four existing methods of partial shading output prediction. It improves the output open-circuit voltage and short-circuit current prediction accuracy by more than 10% when compared with the average irradiance-based modeling approach, which is the best among the existing methods. Overall, an output prediction accuracy of more than 93% is achieved for opaque shading and more than 95% for translucent shading. As this paper provides the output of PV modules under partial shading, it finds direct application in partial shading detection, prevention of hotspots, and global maximum power point tracking, thereby enhancing their life and efficiency.

Impact of fruit-tree shade intensity on the growth, yield, and quality of intercropped wheat.

Agroforestry is a common traditional practice in China-especially in the southern Xinjiang of Northwest China. However, the productivity of many agroforestry systems has been lower than expected in recent years, highlighting the need for an actionably deep mechanistic understanding of the competition between crops and trees. Here, three different fruit tree/wheat (jujube/wheat, apricot /wheat, and walnut /wheat) intercropping agroforestry systems were chosen to investigate influence of different fruit tree shade intensity on the growth, yield and quality of intercropping wheat. Compared to the monoculture wheat system, the mean daily shade intensity of the jujube-, apricot-, and walnut-based intercropping systems were, respectively, 23.2%, 57.5%, and 80.7% shade. The photosynthetic rate of wheat in the jujube-, apricot-, and walnut-based intercropping systems decreased by, respectively, 11.3%, 31.9%, and 36.2% compared to monoculture wheat, and the mean number of fertile florets per spike decreased by 26.4%, 37.4%, and 49.5%. Moreover, the apricot- and walnut-based intercropping systems deleteriously affected grain yield (constituent components spike number, grains per spike, and thousand grain weight) and decreased the total N, P, and K content of intercropping wheat. Tree shading intensity strongly enhanced the grain protein content, wet gluten content, dough development time, and dough stability time of wheat, but significantly decreased the softening degree. Strong negative linear correlations were observed between tree shade intensity and the number of fertile florets, grain yield related traits (including spike number, grains per spike, and thousand grain weight), nutrient content (N, P and K), and softening degree of wheat. In contrast, Daily shade intensity was positively linearly correlated with grain protein content, wet gluten content, dough development time, and dough stability time. We conclude that jujube-based intercropping systems can be practical in the region, as they do not decrease the yield and quality of intercropping wheat.

Improving field establishment of cacao (Theobroma cacao) through mulching, irrigation and shading

AbstractEstablishment of young cacao trees in West Africa can be severely impeded by the onset of the dry season. To address this issue, a field experiment was conducted in Ghana to examine whether different mulch treatments and irrigation applied during the dry season combined with overhead shade could improve survival, early growth and yield of cacao. The mulch treatments used were polyethylene film and coffee husks placed around the young plants. Irrigation was used as a positive control, and no mulching or irrigation was a negative control. Three shade regimes were provided through different arrangements ofGliricidia sepiumand plantains. Four different cacao clones were used in the study in a replicated split-plot design. Early growth of cacao was stimulated under the irrigation and plastic mulch treatments. Higher rates of photosynthesis during the dry season appeared to underlie these increases. Significantly higher early yields were also observed under the irrigation and coffee mulch treatments compared with the control. Plant survival varied significantly between treatments; irrigation was associated with the highest plant survival (94%), followed by the plastic mulch treatment (91%), coffee husk (82%) and the control (70%). There was also an increase in survival when more intense shading was used. Under zero mulch conditions, differences in survival were observed between clones. The clones P 30 [POS] and SCA 6 were more sensitive to drought (in terms of survival) than PA 150 and T 79/501. It is concluded that relatively simple mulching techniques or controlled irrigation in conjunction with appropriate shade management can significantly improve early establishment and cropping of cacao.

Photogeometric Cues to Perceived Surface Shading

The human visual system is remarkably adept at extracting the three-dimensional (3D) shape of surfaces from images of smoothly shaded surfaces (shape from shading). Most research into this remarkable perceptual ability has focused on understanding how the visual system derives a specific representation of 3D shape when it is known (or assumed) that shading and self-occluding contours are the sole causes of image structure [1-11]. But there is an even more fundamental problem that must be solved before any such analysis can take place: how does the visual system determine when it's viewing a shaded surface? Here, we present theoretical analyses showing that there is statistically reliable information generated along the bounding contours of smoothly curved surfaces that the visual system uses to identify surface shading. This information can be captured by two photogeometric constraints that link the shape of bounding contours to the distributions of shading intensity along the contours: one that links shading intensity to the local orientations along bounding contours and a second that links shading intensity to bounding contour curvature. We show that these constraints predict the perception of shading for surfaces with smooth self-occluding contours and a widely studied class of bounding contours (planar cuts). The results provide new insights into the information that the visual system exploits to distinguish surface shading from other sources of image structure and offer a coherent explanation of the influence of bounding contours on the perception of surface shading and 3D shape.

Physiological tipping points to light reduction underlie seagrass population collapse and abrupt shift in a shallow coastal lagoon

Physiological tipping points to light reduction underlie seagrass population collapse and abrupt shift in a shallow coastal lagoon

PENGGUNAAN BEBERAPA MACAM MEDIA DAN TINGKAT NAUNGAN UNTUK MENINGKATKAN PERTUMBUHAN BIBIT KILEMO (Litsea cubeba L. Persoon)

Kilemo ( Litsea cubeba L. Persoon ) is one of the potential economic producing essential oils, because all body part of kilemo’s trees can produce essential oil. The development of kilemo is constrained by the lack of information on cultivation technology. Research on kilemo nursery has been carried out, however the information was not completely provided especially those related to shading and media. Therefore the purpose of the study is to get information on the response of kilemo seedlings on the use of shade and media in the nursery. The study was conducted in a Greenhouse of Forest Tree Seed Technology Research & Development Center (FTSTRDC) Bogor. The experiment used Completely Randomized Design with Factorial Pattern, consisted of 2 factors and 10 replications. The first factor is media consisting of 5 types of media: soil; compost charcoal;soil + compost charcoal 3:1 (v/v); soil + paddy husk charcoal 3:1 (v/v); and soil + charcoal compost + paddy husk charcoal 3: 1: 1 (v/v/v). The second factor is shade consisting of 4 shade intensity that is: 0 percent , 25 percent , 50 percent , 75 percent . The results showed that Media of soil + paddy husk charcoal 3:1 (v:v) with shade 25 percent gives the best growth to Litsea cubeba ’s seedlings 5 months after weaning on the parameters of height (12.64 cm), number of leaves (5.56), dry weight (0.182), seed quality index (0.021) and TR ratio (1.967).

Biogeographical scenarios modulate seagrass resistance to small‐scale perturbations

Abstract Seagrasses constitute a key coastal habitat world‐wide, but are exposed to multiple perturbations. Understanding elements affecting seagrass resistance to disturbances is critical for conservation. Distinct biogeographical scenarios are intrinsically linked with varying ecological and evolution backgrounds shaped across millennia. We addressed whether the resistance (change in shoot abundances) and performance (change in leaf morphology and growth) of the seagrass Cymodocea nodosa to a local stressor, light reduction, varied across three regions (Southeast Iberia, the Balearic Sea, and the Canaries) within the temperate northern Atlantic realm. We hypothesized that distinct biogeographical scenarios, in terms of distinct ecological/environmental conditions and genetic diversity of meadows, would affect seagrass resistance and performance, with flow‐on effects on associated epifauna. The same experiments, in terms of shading intensities, timing and duration, were replicated at three seagrass meadows within each region. Results demonstrated inter‐regional variation in the resistance and performance of C. nodosa. Under moderate and high shading, shoot abundance was abruptly decreased, relative to controls, in the Canaries with concurrent, but less accentuated, changes in leaf morphology and no changes in growth. In the other two regions, however, moderate and high shading had a negligible effect on shoot abundance, leaf morphology, and growth. Shading had no overall effect over the total abundance and assemblage structure of epifauna; these faunal attributes, however, varied between regions. Low seagrass resistance at the Canaries is linked with the peripheral distribution of the species there, favouring isolation and decreased genetic diversity. Synthesis. Different biogeographical scenarios shape seagrass resistance to local perturbations. From a conservation perspective, if resistance differs among biogeographical scenarios, universal conservation rules for seagrasses are challenging.

Adaptasi Tanaman Indigofera zollingeriana (Miquel 1855) (Leguminosae : Indigofereae) pada Berbagai Tingkat Naungan

Indigofera zollingeriana is a bush type legume plant that grows well in full light but tolerant to shade conditions. Modification efforts of the environment with paranet shade treatment are the accurate approach. The objective of this research was to study the tolerance limit of I. zollingeriana plant at various shade levels. The study was conducted in October 2016-April 2017 at the Leuwikopo-IPB Bogor and used randomized block design with one shade factor (0, 40, 65, and 80%). The results of the measurement of microclimate with various shading levels showed that in the shade treatment 40%, the intensity of light decreased by 40% the temperature decreased by 6%, while the humidity increased by 10%. In the 65% shade, the light intensity decreased by 62%, the temperature decreased by 10%, while the humidity increased by 24%. In the 80% shade, the light intensity decreases 95%, the temperature decreases 13%, while the humidity increases 34%. The shade intensity has a real significant on decreasing stem diameter, number of branches, canopy dry weight, and roots. I. zollingeriana is rather tolerant of shade and it is able to adapt to shade up to 40%.

Light intensity controls rhizosphere respiration rate and rhizosphere priming effect of soybean and sunflower

Rhizosphere respiration (Rroot) and rhizosphere priming effect (RPE) are crucial for regulating soil carbon dynamics. However, their responses to light intensity are not fully resolved. We investigated Rroot and RPE of soybean and sunflower using a continuous isotope-labeling technique. The two species were subjected to five levels of light intensity in a growth chamber. Plants were maintained at full light from seeding for 45 or 59 days, and switched to shading treatments for four days. Soil respiration was partitioned into root- and soil-derived CO2 during the last five days (day0, full light; day1–4, shading). Both soybean and sunflower Rroot showed significant positive relationships with light intensity, particularly after one day of shading. Moreover, both plants showed positive RPE (44–98%) at full light, but with increasing duration and intensity of shading, the RPE declined and even became negative (up to –20%). Indeed, a positive relationship between light intensity and RPE was observed in both species. Overall, our results showed that shading, by influencing light intensity and presumably photosynthesis rate and belowground carbon allocation, exerts a significant control of rhizosphere respiration rate and priming effect of the two species.

Effect of brassinolide application on antioxidant characteristics and endogenous hormones of Leymus chinensis (Trin.) Tzvelev under different light intensity regimes

Different light and shade intensities are the main constraints to achieve potential biomass accumulation in Leymus chinensis (Trin.) Tzvelev. An experiment was conducted to explain the physiochemical and morphological adversity triggered by various light intensities. Adverse impacts were lessened with exogenous brassinolide (BR). Treatments consisted of 100% natural light (T0), 100% natural light + 0.1 mg L-1 BR (BT0), light shade (70% natural light) (T1), light shade + BR (70% natural light + 0.1 mg L-1 BR) (BT1), moderate shade (50% natural light) (T2), and moderate shade + BR (50% natural light + 0.1 mg L-1 BR) (BT2). These were completely randomized design treatments with five replicates. Results showed that dry biomass production and endogenous hormone levels (abscisic acid [ABA], zeatin riboside [ZR], gibberellic acid [GA], and indole acetic acid [IAA]) increased, while osmolyte accumulation (soluble sugars and proteins, free amino acids, and proline), antioxidant activity (peroxidase [POD], superoxide dismutase [SOD], and catalase [CAT]), and lipid peroxidation decreased under shade at T0. Treatment T1 depicted the most promising results for these attributes. However, biomass accumulation (33%-56%), osmotic substances (soluble sugars,13%-38%; soluble proteins, 9%-41%; free amino acids, 8%-16%; proline, 11%-41%), and antioxidant enzyme activities (POD, 11%-14%; SOD, 3%-33%; CAT, 4%-23%) increased. On the other hand, lipid peroxidation was reduced by BR application, as indicated by decreased malondialdehyde (MDA) content (7%-31%) and relative conductivity (7%-19%) under both natural and shade conditions. Likewise, the biosynthesis of ABA (2%-22%), ZR (11%-24%), and GA (30%-50%) improved under exogenous BR compared with the control. The IAA contents (22%-28%) decreased under foliar-applied BR compared with the control. Results suggested that light to moderate shade improved the biomass production and physiological performance of L. chinensis, while BR application exhibited further improvement

Productivity and Quality of Three Varieties of Ginger on Many Light Intensity Levels Under Stand of Pine

The high demand of medicinal plants with limited agricultural land availability can be solved by the utilization of land under forest canopy through applying agroforestry. This study aim s to assess the effect of different varieties of ginger and different shading intensities of pine ( P inus merkusii ) on the productivity and quality of ginger. The design used was a split plot design consisting of 3 replicates with an area of 100 m 2 for each plot and with spacing of 50 x 50 cm. The main plot is the light intensity treatments, i.e. 50-58% (age class I I), 68-77% (age class I) and 87-92% (poor increment), whereas the sub plot is the varieties of ginger i.e.: small white ginger (emprit), large white ginger (gajah) and red ginger. R esults showed that the light intensity does not significantly affect the percentage of growth, moisture content, volatile oil, fiber, starch and ash. Varieties of ginger significant ly a ffect the percentage of growth, h e igh t growth and weight of rhizome, but do not significantly affect the moisture content, volatile oil, fiber, starch and ash . The a verage yield of each variety of ginger is 5.54 tons/ha , 8.38 tons/ha and 6.7 ton /ha for small white ginger, large white ginger and red ginger , respectively. Agroforestry of ginger plant under pine stand can be done to improve land productivity, especially in poor stand increment .

Structure of cocoa farming systems in West and Central Africa: a review

Cocoa agroforests are growing in importance with a view to meeting farmers’ livelihood goals as well as ecological services. Following the recognition of cocoa agroforests as being useful for biodiversity conservation and farmers’ livelihoods, there is a growing discourse on the fact that they may also be useful in climate change mitigation and biodiversity conservation. Several companies have expressed their willingness to be “deforestation” certified within the next two decades. In West and Central Africa, cocoa is part of the endeavour to contribute to the REDD+ mechanism. Besides producing cocoa beans, the additional expectations from cocoa agroforests (timber, NWFP, biodiversity conservation, carbon storage, etc…) depend on the trees associated with the cocoa plants. The manner in which associated trees are mixed in the system impacts on the cocoa plants and plants associated with cocoa trees within the agroforestry system thus impact on the products and services produced by these farming systems. Studies are being undertaken to identify the exact composition of these associated trees but very few deal with the manner in which these trees are structurally distributed—vertically and horizontally—within the cocoa agroforest. Understanding the way in which cocoa and non-cocoa trees are distributed within the system would be useful with a view to improving the farm system, thus meeting the needs of several stakeholders. The present study reviews the structure of cocoa orchards and agroforests in West and Central Africa (Cameroon, Nigeria, Ghana and Cote d’Ivoire) with a view to improving the products and services of cocoa landscapes. This review is centred around: (i) density of cocoa, (ii) density of associated plants, (iii) basal area or associated plants, (iv) stratification and space between components, and (v) the life cycle of cocoa plantation components. Densities of cocoa and associated plants in the field are not always those advised by extension services. The cocoa varieties play an important role in type and intensity of shade of the cocoa farms. In the context of multiple expectations placed on cocoa plantations, the unproductive cocoa trees in the farmer fields can be substituted by more vigorous ones or replaced by useful associated plants (Timber and NWFP). With the growing desire to reproduce some key attributes of local forests while responding to other economic and social needs associated with cocoa farms, the neighbouring/previous forest climax and its related basal area can be considered as a reasonable aim, when managing the cocoa agroforest. The life cycle of each of the plant components needs to be optimized in these spatial–temporal intensification considerations. In the prospect of vertical intensification, there is a need to give more attention to understorey management and the number of strata of the agroforest. In the context of sustainable management, a well-structured cocoa agroforest system needs to take landscape, local, national and global socio-economic and political issues into consideration.

How Munsell system could help visualize color variation on cement tiles

AbstractCement tiles are particularly susceptible to intense shade variation. We have observed that there are many factors which influence the tiles coloring, from the way the mixture and the paint are prepared and manipulated to the weather conditions on the day of manufacturing and during the 40 days of the drying process, and even the way the tiles are displayed on the shelves. Partial results have shown that even pieces from the same batch, which are painted the same color using the same pigment, will display some color variation. The wonder of such work is that each piece might be unique, once there is no way to ensure the whole lot will have the same value and chroma. By applying the Munsell System to the colors in the company's catalog, this study has aimed to detect the range of possible luminosity and saturation variation, considering such tonality variation as a legit product of handcrafted production.

DETERMINATION OF SOIL QUALITY AS A FOUNDATION OF SUSTAINABLE LAND MANAGEMENT FOR CHILLI IN THE AGROFORESTRY SYSTEM BASED ON COCONUTS IN SANDY SOIL OF BUGEL BEACH

The quality of soil cannot be measured directly, in which indicators need to be arbitrated of physical, chemical and biological properties, all of those affect the character of soil. The objective of this study was to identify the relationship between factors of soil quality and to review the effect of soil quality towards chili production. The exploration was done at Bugel Beach, Panjatan Sub-District, Kulonprogo, and DIY. Methods that were used in this study were Randomized Complete Block Design (RCBD) single factor. The factors was divided into initial agroforestry zone (shade intensity 0-30%), middle (shade intensity 31-60%) and final (shade intensity &gt;60%) based on coconuts that was present at the location of sandy soil of Bugel Beach. Data collection was in physical, chemical, and biological form also in chili production. Data analyses were ANOVA with 5% LSD test, Structural Equitation Modelling (SEM), Factor Analysis and Stepwise Regression. The result of this study showed that initial agroforestry phase had the highest chilli production which followed by middle agroforestry and final agroforestry phase. SEM result showed that biological characteristic of soil in general directly affect the chili production and an interaction was evidence between physical and chemical characteristics of the soil. Two sets of the factors were found in factor I (BV, soil moisture, permeability, pH H2O, C-Organic, KPK, N-total, P-total, P-availability, K-total, K-dd, Ca-dd, mg-dd, Na-dd and total of microbes) and factor II (microbial and respiration total). Quality factor which effected chili production was the amount of total microbes.

Seed Analysis and Seedling Production of Matayba elaeagnoides Radlk

The objective of this study was to evaluate the germination potential of Matayba elaeagnoides seeds, identifying the best substrate for laboratory analysis and to determine seedling emergence and growth under different shade levels in the nursery. Different substrates (paper roll, between and on blotting paper, and on sand or vermiculite) were evaluated in the germination test and different shade levels (0, 30, 50 and 75%) were tested in the nursery. No differences were found between the substrates for seed germination, however, the highest germination percentage was observed when using paper roll (70%). The 30, 50 and 75% shading intensities positively influenced Matayba elaegnoides seedling emergence, however, the best performance in nursery growth was observed under 75% shade presenting seedlings with better standard and quality.