Shading Intensity Research Articles

Plant diversity effects on the water balance of an experimental grassland

ABSTRACTIn the literature, contrasting effects of plant species richness on the soil water balance are reported. Our objective was to assess the effects of plant species and functional richness and functional identity on soil water contents and water fluxes in the experimental grassland of the Jena Experiment. The Jena Experiment comprises 86 plots on which plant species richness (0, 1, 2, 4, 8, 16, and 60) and functional group composition (zero to four functional groups: legumes, grasses, tall herbs, and small herbs) were manipulated in a factorial design. We recorded meteorological data and soil water contents of the 0·0–0·3 and 0·3–0·7 m soil layers and calculated actual evapotranspiration (ETa), downward flux (DF), and capillary rise with a soil water balance model for the period 2003–2007. Missing water contents were estimated with a Bayesian hierarchical model. Species richness decreased water contents in subsoil during wet soil conditions. Presence of tall herbs increased soil water contents in topsoil during dry conditions and decreased soil water contents in subsoil during wet conditions. Presence of grasses generally decreased water contents in topsoil, particularly during dry phases; increased ETa and decreased DF from topsoil; and decreased ETa from subsoil. Presence of legumes, in contrast, decreased ETa and increased DF from topsoil and increased ETa from subsoil. Species richness probably resulted in complementary water use. Specific functional groups likely affected the water balance via specific root traits (e.g. shallow dense roots of grasses and deep taproots of tall herbs) or specific shading intensity caused by functional group effects on vegetation cover. Copyright © 2013 John Wiley & Sons, Ltd.

Influence of colour net shading on quantity and quality of sweet pepper yield

Sweet pepper (Capsicum annuum L.) is one of the main cultivated vegetable species in Hungary mostly produced under plastic tunnel by unheated technology. Sweet pepper plants could suffer high temperature and radiation during summer season. However, photoselective-shading nets can provide a new tool for light quality manipulation and support the plant development and fruit quality. The effect of shading colour nets depends on natural light conditions and other environment factors; therefore it is necessary to evaluate the shading technology. Hungarian sweet pepper variety was grown in South-East part of Hungary under plastic tunnels using different colour nets, as white, yellow, green and red, for shading in 2013. Results of trial proved that green colour shading net usually decrease the yield, while yellow and red nets can increase the yield and the fruit quality of Hungarian type sweet pepper. Growers have to care the shading intensity of the net, which should not be higher than 35-40%. Colour shading nets can be placed onto the plastic tunnels just after the planting.

遮荫对苦丁茶树叶片特征及光合特性的影响

We study the effect of different shading treatments( 0,20%,40% and 60% shade) on the leaf growth and photosynthetic characteristics of Ligustrum robustum through artificial shade,aiming to provide scientific advices for cultivation and management of the species. The results showed that( 1) the leaf width,leaf area and leaf thickness at 40%shade of L. robustum were significantly higher than those under other three different treatments; the palisade tissue thickness( 64. 70 μm) at 40% shade of L. robustum was significantly higher than those under other three different treatments; there were two palisade tissue layers at 40% shading treatment comparing to one layer at the other three different treatments. The contents of total chlorophyll,chlorophyll a and chlorophyll b in leaves under the shading conditions were significant higher than those under the full daylight,and the chlorophyll contents increased with the increasing of shading levels. That L. robustum showed significantly higher leaves growth and the best overall growth anddevelopment at 40% shading treatment,which could be regarded as an appropriate shading intensity for its growth and development of L. robustum.( 2) The net photosynthetic rate increased at 40% shading treatment but decreased at 60%shading treatment. The stomatal conductance,internal carbon dioxide concentration and transpiration rate increased while the vapor pressure deficit decreased at both 20% and 40% shading treatment,which was helpful for photosynthesis. The vapor pressure deficit was highest while stomatal conductance and internal carbon dioxide concentration lowest at the 0%and 60% shading treatment comparing to other shade treatments,which suppressed net photosynthetic rate and transpiration rate of the plants.( 3) The dark respiration and light compensation point declined in the shading treatments while the 40%shading treatments resulted in the increases of the apparent quantum efficiency and maximum net photosynthetic rate,which indicated that L. robustum had shade tolerance to some extent. The Fv /Fm and Fv /Fo became smaller as the increase of shading level,the Fv /Fm of 20%,40% and 60% shading treatments were about 2. 71%,4. 59% and 8. 03%significantly lower than that under full day light respectively,and the Fv /Fo of 20%,40% and 60% shading treatments were about 6. 89%,11. 99% and 19. 81% significantly lower than that under full day light respectively. All fluorescence parameters of 40% shading treatment were significantly lower than those under the other three different treatments. Shading significantly depressed the efficiency of chlorophyll molecules capture excitation energy and potential activity of photosystemⅡ( ΦPSⅡ). In summary,L. robustum is shade-tolerant plants,and 40% shading treatment( the daily PAR values within the range of 273—1222 μmol·m-2·s-1) is an appropriate light environment,which could significantly improve leaves growth and photosynthetic capacity.

A molecular assessment of the genetic model of spathe color inheritance in Anthurium andraeanum (Hort.)

Past genetic studies have shown three independent loci designated O, R and M control spathe color in Anthurium andraeanum (Hort.). To evaluate the genetic model and to understand the control of anthocyanin biosynthesis at the molecular level, the expression of the anthocyanin biosynthetic genes, CHS, F3H, DFR, ANS and F3'H, was examined at the mRNA and protein levels and correlated to anthocyanin content and spathe color in eight genetically characterized anthurium cultivars representing different states of the O, R and M loci. The results showed that the expression of F3H and ANS was co-regulated by a putative transcription factor encoded by the R locus, and the expression of DFR was regulated by a putative transcription factor encoded by the O locus. White cultivars, which were in the homozygous recessive state for either O or R or both, exhibited reduced expression of the anthocyanin biosynthetic genes and hence had negligible levels of anthocyanin. Cultivars that were mm displayed reduced expression of F3'H suggesting that it may either encode a defective form of the F3'H gene or a regulator that controls its expression. Additionally, a correlation between anthocyanin abundance and the expression of F3'H in the red cultivars suggested that F3'H expression may be a key control point in the regulation of anthocyanin biosynthesis in anthurium and hence plays a major role in influencing the shade intensity in red cultivars. These findings provide evidence in support of the genetic model for color inheritance in the spathe.

Shade Intensity Influences Water Use and Growth of Three Viburnum Species

Water use, growth, and leaf necrosis of Burkwood viburnum, Korean spice viburnum, and leatherleaf viburnum were evaluated on plants grown in 0 (full sun), 30, or 60% shade during 2010 and 2011. In both years, total water use of Burkwood viburnum decreased with increased shade intensity. Water use of leatherleaf viburnum was lowest in 0% and highest in 30% shade. Daily water use was lower in 0% than in 30 or 60% shade for leatherleaf viburnum plants in August of both years and September of 2010 due to greater leaf necrosis, leaf abscission, and less growth in height and width. In both years, growth in height and width, and leaf number at harvest generally increased in all three species with increased shade intensity. All species had a larger leaf area, stem dry weight, and root dry weight in 30 and 60% than in 0% shade. Shade intensity did not influence root to shoot (R/S) ratio in Burkwood viburnum in 2010, but in 2011, a curvilinear relationship occurred between R/S ratio and shade intensity. Root to shoot ratio of Korean spice and leatherleaf viburnum decreased linearly in 2010 but curvilinearly in 2011 with increasing shade. Leaf necrosis ratings were lower in shaded plants of all three species in both years. Results indicate that greater plant growth, quality, and water use efficiency occurs when these three viburnum species are grown in shade than when they are grown in full sun.

Gender Variation in a Monoecious Woody VineSchisandra chinensis(Schisandraceae) in Northeast China

Demographic variation of gender expression among four natural populations and one cultivated in a monoecious species, Schisandra chinensis (Schisandraceae), was studied over three consecutive years in a bid to clarify its sexual system and to better understand reproductive strategies in monoecious plants. We found that gender expression was more variable in the natural populations than in the cultivated one. In the natural populations, plant size was positively correlated with flower production (total, male and female) but not with the female ratio, whereas shade intensity was negatively correlated with the female ratio. In the cultivated population, plant age was positively correlated with flower production and the female ratio within an age range. Hence, gender expression and reproductive output in Schisandra chinensis was found to be age-dependent. The female ratio varied with age; young and old plants had lower female ratios. Our study confirmed the sexual system in the species to be monoecy as opposed to dioecy, and supported the hypothesis that monoecious plants can regulate gender expression by altering quantities of pistillate and staminate flowers at the individual plant level to maximize fitness.

Effects of Light Intensity on Ear Differentiation of Barren-Stalk Defective Maize

Ear differentiation of different shade-resistance maize were studied under the shade stress using paired near isogenic, easy barren-stalk and not easy barren-stalk hybrids and inbred lines as test materials. The test verified the phenomenon of genetic defective barren stalk of maize preliminarily, revealed the relationship between barren stalk under the shade stress and ear differentiation and light intensity range inducing maize genetic defective barren stalk. Low light stress would make different varieties cause barren stalk and differences among varieties were obvious; easy barren stalk near-isogenic Shennong 98A was the most sensitive to low light stress and the stress intensity should be below 38% shade. Shade resistance of non-barren stalk near-isogenic Shennong 98B was close to normal inbred line Chang 7-2 and its intensity range of light stress were between 38%~60% shade; there were significant differences between hybrids of easy barren stalk D90, D80 and non-easy barren stalk Zheng Dan 958 under the 75% shade; shade stress could make young female ear short, grains per panicle reduce, the number of abortive grain increase and rates of barren stalk increase, which would aggravate with the increase of shade intensity and the reactions of easy barren stalk varieties were much more obvious, even caused 100% barren stalk led by female ear agenesis.

GW24-e2928 Computed tomography metal artifact reduction for evaluation of lead calcification in patients with implantable cardiac defibrillator

ObjectivesPatients with implantable cardiac defibrillator (ICD) may require lead extraction if there is presence of lead fibrosis and calcification but such procedure requires specialist equipment and skills and is associated...

PENGARUH KOMBINASI INTENSITAS NAUNGAN DENGAN ZAT PENGATUR TUMBUH INDOLE BUTIRIC ACID (IBA), NAPHTHALENE ACETIC ACID (NAA), DAN VITAMIN B1 DALAM AKLIMATISASI PERTUMBUHAN BIBIT GAHARU (Aquilaria beccariana)

The objective of this research is to know the optimal formula of Indole Butiric Acid (IBA), Naphthalene Acetic Acid (NAA), Vitamine B1 and the combination with shading intensities to the acclimatization of Gaharu stump (Aquilaria beccariana). This research used Factorial Design with basic analysis of Complete Randomized Design in order to know theeffect of treatment. The research was carried out in Agroindustry and Biotechnology Laboratory, Ciampea, Bogor, from July to September 2007. The results of the research showed that after 8 weeks of treatment: (a). The combination of 55 % shading intensity with IBA 15 mg/l + NAA 10 mg/l + Vitamine B1 1 mg/l was the best formula for increasingheight of Gaharu stump 4.660 cm. (b). The combination of 55 % shading intensity with IBA 15 mg/l + NAA 30 mg/l + Vitamine B1 1 mg/l was the best formula for increasing sum of Gaharu leaf stump 12.337 leafs, (c). The combination of 55 % shading intensity with IBA 15 mg/l + NAA 40 mg/l + Vitamine B1 1 mg/l was the best formula for increasing sumof Gaharu root stump 3.783 roots, and (d). The combination of 55 % shading intensity with IBA 15 mg/l + NAA 40 mg/l + Vitamine B1 1 mg/l was the best formula for increasing length of Gaharu root stump 3.686 cm.

Productivity and fruit quality of Vaccinium corymbosum cv. Elliott under photo-selective shading nets

The productivity and development of northern highbush blueberry plants (Vaccinum corymbosum L. cv. Elliott) was examined under photo-selective nets of different colors (black, red and white) and shade intensities (25%, 50% and 75%) in Michigan-USA over two growing seasons. Photoselective nets influenced the photosynthetic active radiation (PAR) transmitted through the canopy, with white nets allowing significantly higher radiation to penetrate than red and black nets at all shade levels. After one year of treatment, the rate of flower bud development decreased linearly as % PAR increased, but the total number of flower buds per cane and terminal shoots increased gradually as light levels increased, reaching an asymptote at 50% PAR. The percentage of mature fruit on a particular date was higher in the control plants and decreased as the % PAR was reduced. The harvest delay was maximum at the lowest light level (20%) and decreased exponentially with increasing % PAR. Fruit soluble solids increased linearly (r2=0.86; P<0.0001) and fruit water content decreased linearly (r2=0.88; P<0.0001) as % PAR increased. Fruit yield showed a positive, curvilinear relationship with % PAR and reached an asymptote at 50% PAR. The interaction between color and shade was not significant. However, fruit quality (fruit weight, soluble solid and firmness) showed significant color×shade and color×harvest time (fruit weight, soluble solids and titratable acidity) interactions. Our results indicate that placing red and white nets over mature plants at intermediate shade levels (40–60% PAR) provide a harvest delay without detrimental effects on return bloom, yield or fruit quality.

Fine-scale distribution of pelagic fishes relative to a large urban pier

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 476:185-198 (2013) - DOI: https://doi.org/10.3354/meps10151 Fine-scale distribution of pelagic fishes relative to a large urban pier Kenneth W. Able1,*, Thomas M. Grothues1, Iris M. Kemp2 1Rutgers University Marine Field Station, Tuckerton, New Jersey 08087, USA 2University of Washington, School of Aquatic & Fishery Sciences, Seattle, Washington 98195-5020, USA *Email: able@marine.rutgers.edu ABSTRACT: Intense shading under large piers is known to negatively affect benthic fishes. However, effects on pelagic fishes are poorly known. We employed the equivalent of acoustic video, dual frequency identification sonar (DIDSON), under a kayak to evaluate the response of pelagic fishes at a large (351 × 255 m) urban pier (Pier 40) in Hudson River. A repeated measures design (322 occupations) sampled 3 transects each across both the northern and southern open water—pier edge—under pier continuum during the day and night from June 2009 to September 2010. Over 22000 individual fish, ranging from small schooling forage species (e.g. Anchoa mitchilli, Menidia menidia) to large predators (Morone saxatilis, Pomatomus saltatrix) were detected with DIDSON and verified with conventional sampling nets. Small (<250 mm) schooling pelagic fishes avoided areas under the pier where light is dramatically reduced during both day and night (when municipal lights illuminate the water away from the pier). Less abundant large (>250 mm) predatory fish responded somewhat differently from small schooling fish in that large predatory fish were slightly more abundant under the pier than in open water, but only from the edge extending to 5 m under the pier where there was still some light. Beyond that, abundance declined sharply. Together, these observations indicate that areas under large piers are suboptimal habitats for many of the abundant pelagic fishes, a pattern similar to that for benthic fishes. KEY WORDS: Pier · Shade · Edge · Pelagic fish · Distribution · DIDSON Full text in pdf format PreviousNextCite this article as: Able KW, Grothues TM, Kemp IM (2013) Fine-scale distribution of pelagic fishes relative to a large urban pier. Mar Ecol Prog Ser 476:185-198. https://doi.org/10.3354/meps10151 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 476. Online publication date: February 27, 2013 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2013 Inter-Research.

Responses of photosynthetic characteristics and antioxidative metabolism in winter wheat to post-anthesis shading

In a field experiment, two winter wheat (Triticum aestivum L.) cultivars, Tainong 18 (a large-spike cultivar) and Jinan 17 (a multiple-spike cultivar), were treated with 78% (S1), 50% (S2), and 10% (S3) of full sunshine (S0, control) from anthesis to maturity to determine the responses of photosynthetic characteristics and antioxidative enzyme activities in a flag leaf. Compared with S0 treatment, the chlorophyll (Chl) content and maximal efficiency of photosystem II (PSII) photochemistry (Fv/Fm) of flag leaves were enhanced in treatments S1 and S2. From 0 to 7 d post flowering, the Chl content and Fv/Fm in S3 were also higher than those in S0, but significantly lower than those in controls, respectively. With the increase of shading intensity, the effective quantum yield of PSII (ΦPSII) was promoted; whereas, the ratio of Chl a/b declined. Compared with S0, treatments S2 and S3 significantly suppressed the activities of superoxide dismutase (SOD) and peroxidase (POD), net photosynthetic rate (P N), and contents of total soluble sugar, nevertheless, S1 treatment showed positive effects on the above parameters. Under the same shading condition, Jinan 17 had larger Chl content and higher activities of PSII and antioxidative enzymes, but lower malondialdehyde (MDA) content than Tainong 18. The results indicated that multiple-spike cultivar was more advantageous for the Huang-Huai-Hai Plain, where shading problem occurs later during the growth period, than the large-spike cultivar, because of the lesser damage in a flag leaf and better photosynthetic function of the former one. Wheat plants under S1 shading condition had relatively high activities of antioxidative enzymes and a low degree of membrane lipid peroxidation, which was in favor of stress resistance, maintaining high P N duration, and accumulation of photosynthates in wheat plants.

Photosynthetic induction and activity of enzymes related to carbon metabolism: insights into the varying net photosynthesis rates of coffee sun and shade leaves

The shade leaves of coffee (Coffea arabica L.) apparently retain a robust photosynthetic machinery that is comparable to that of sun leaves and can fix CO2 at high rates when subjected to high light intensities. This raises the question of why the coffee plant would construct such a robust photosynthetic machinery despite the low photosynthetic rates achieved by the shade leaves at low light supply. Here, we grew coffee plants at 100% or 10% full sunlight and demonstrated that the shade leaves exhibited faster photosynthetic induction compared with their sun counterparts, in parallel with lower loss of induction states under dim light, and were well protected against short-term sudden increases in light supply (mimicking sunflecks). These findings were linked to similar photosynthetic capacities on a per mass basis (assessed under nonlimiting light), as well as similar extractable activities of some enzymes of the Calvin cycle, including Rubisco, when comparing the shade and sun leaves. On the one hand, these responses might represent an overinvestment of resources given the low photosynthetic rates of the shade leaves when light is limiting; on the other hand, such responses might be associated with a conservative behavior linked to the origin of the species as a shade-dwelling plant, allowing it to maximize the use of the energy from sunflecks and thus ultimately contributing to a positive carbon balance under conditions of intense shading.

Yield components of maize as affected by short shading periods and thinning

Maize (Zea mays) grain yield has been described to be particularly susceptible to environmental conditions around silking; however, a better temporal description of the effect of resource deprivation during this period is needed. Additionally, yield progress and the subsequent increase in the demand of assimilates may result in source limitation during the grain-filling period in current hybrids. This work assessed the effect of (i) short (~5 days) and intense shading stresses imposed at different times, and (ii) thinning during the effective grain-filling period, on yield components of an Argentinean, widespread hybrid. Grain yield was affected by resource availability during an extended period from ~300 growing degree-days (GDD) before silking to ~780 GDD after silking (base temperature = 8°C). Kernel number (KN) was reduced by shading treatments imposed within a relatively extended period of ~700 GDD centred on silking. Within this period, we establish a critical period of ~30 days around silking (i.e. –200 to 250 GDD after silking), in which KN susceptibility was maximal. The variation in KN during this period of 450 GDD was mainly accounted for by resource availability and not by timing of treatment imposition within this window. A direct relationship between KN and weight per kernel (KW) for shading treatments imposed from 0 to 200 GDD after silking indicated that compensation of KN reduction by KW increase might not be expected when stress occurred immediately after silking. Kernel number and KW presented an inverse relationship when shading took place after 200 GDD after silking. In addition, thinning after the onset of the effective grain-filling period increased KW. The results indicate that, even in the undisturbed crop, KW was limited by source capacity during grain filling. It is suggested that there is a need to reconsider current agronomic practices and breeding strategies, focusing on the source capacity during the grain-filling period.

Towards a neuroscience of social interaction.

Towards a neuroscience of social interaction.

Latitudinal differences in thermoregulatory color change in Uca pugilator

Animals can change color either rapidly in response to changes in their immediate environment or slowly as the seasons change. Such plasticity can permit local adaptation but it can also be constrained by physiological and behavioral mechanisms. Here, we explore how different temperature regimes along a latitudinal gradient spanning the natural range of a species of fiddler crab may affect the ability of crabs to change color rapidly in response to acute changes of temperature. Uca pugilator populations from New York (NY), North Carolina (NC) and Florida (FL) were exposed in air to 5°C and 35°C and carapace shade intensity (from dark to light color) and contrast was recorded. In general, individuals darkened when exposed to cold conditions, and lightened when exposed to warm conditions. Males from different populations differed in the magnitude of response to temperature, but had similar directional changes in shade (dark under cold conditions and light under warm conditions) suggesting differences among populations in the ability to change color. Females showed similar directional changes but there were no differences among populations. Differential responses of crabs to temperature suggest that crabs have local physiological adaptations and can acclimate quickly to withstand fluctuating or extreme temperatures.

Assessing Light Competition for Cereal Production in Temperate Agroforestry Systems using Experimentation and Crop Modelling

AbstractIn every agroforestry system, the tree canopy reduces the incident radiation for the crop. However, cereal varieties were selected, and most crop growth models were designed for unshaded conditions, so both may be unsuited to agroforestry conditions and performance. In southern France, durum wheat productivity was monitored over 2 years in an agroforestry system including walnut trees and under artificial shade conditions. Yield components were measured in both full and reduced light conditions. The cereal yield was always decreased by shade; by almost 50% for the heaviest shade conditions (31% of light reduction). The main effect of the shade was the reduction in the number of grains per spike (35% at the most) and in the weight of grains (16% at the most). The mean grain weight was moderately affected, while the protein content was increased in shaded conditions (by up to 38% for artificial shade). Consequently, the protein yield per hectare was less reduced by the shade than the dry matter grain yield. A crop model (STICS) was also used to simulate the crop productivity in full light and shaded conditions, but the crop LAI and the yield components were not correctly simulated in the shade. The simulations emphasized the sensitivity of the wheat grain filling to shade during the critical period, 30 days before flowering, for yield elaboration. Further experimental and modelling studies should take into account the heterogeneity of shade intensity due to the shape of the tree crown, the width of the crop alley and the orientation of the tree rows and the modification of carbon allocation inside the plant.

TRANSPIRATION AND PHOTOSYNTHESIS OF SWEET PEPPER GROWING UNDER DIFFERING SCREENHOUSE NETS

The influence of three screenhouse nets differing in colour, shading intensity (SI) and porosity on photosynthesis, transpiration rate and light acclimation of sweet pepper plants was investigated at Velestino (central Greece) from May to October 2011. The screenhouse nets consisted of two insect-proof white nets (W13 and W34, SI=13 and 34%, respectively), and a green shading net (G36, SI=36%). Climate variables were recorded continuously in the different treatments. Leaf photosynthesis and transpiration rate were measured fortnightly over different canopy layers. The results indicated that drastic changes in light regime induced by shading nets had only a slight effect on leaf gas exchange and water use efficiency. Ontogenic effects (leaf ageing) appeared to be the main factor responsible for the observed seasonal pattern of leaf photosynthetic attributes. Overall, sweet pepper plants grown under screenhouse treatments appeared to display a physiological response and light-acclimation across a large interval of SI that was close to that observed for the field grown crop, irrespective of the colour and porosity of the nets.

Temporal Coherence Methods in Real‐Time Rendering

AbstractNowadays, there is a strong trend towards rendering to higher‐resolution displays and at high frame rates. This development aims at delivering more detail and better accuracy, but it also comes at a significant cost. Although graphics cards continue to evolve with an ever‐increasing amount of computational power, the speed gain is easily counteracted by increasingly complex and sophisticated shading computations. For real‐time applications, the direct consequence is that image resolution and temporal resolution are often the first candidates to bow to the performance constraints (e.g. although full HD is possible, PS3 and XBox often render at lower resolutions).In order to achieve high‐quality rendering at a lower cost, one can exploit temporal coherence (TC). The underlying observation is that a higher resolution and frame rate do not necessarily imply a much higher workload, but a larger amount of redundancy and a higher potential for amortizing rendering over several frames. In this survey, we investigate methods that make use of this principle and provide practical and theoretical advice on how to exploit TC for performance optimization. These methods not only allow incorporating more computationally intensive shading effects into many existing applications, but also offer exciting opportunities for extending high‐end graphics applications to lower‐spec consumer‐level hardware. To this end, we first introduce the notion and main concepts of TC, including an overview of historical methods. We then describe a general approach, image‐space reprojection, with several implementation algorithms that facilitate reusing shading information across adjacent frames. We also discuss data‐reuse quality and performance related to reprojection techniques. Finally, in the second half of this survey, we demonstrate various applications that exploit TC in real‐time rendering.

Landuse intensity in stream catchments affects the benthic food web: consequences for nutrient supply, periphyton C:nutrient ratios, and invertebrate richness and abundance

Anthropogenic nutrient enrichment increases the supply ratio of N and P to aquatic ecosystems and can affect the identity of the limiting nutrient. Here we focus on how stream communities change along gradients of N and P supply and stream catchment landuse intensity. We used a survey approach in 41 southern New Zealand tributaries to investigate how much changes in water N and P concentrations are reflected in periphyton C∶nutrient ratios (C∶N or C∶P) and how much food quality (high food quality corresponds to low periphyton C∶nutrient) is reflected in the abundance and taxonomic richness of benthic invertebrate primary and secondary consumers. We measured streamwater nutrient state, periphyton nutrient ratios, biomass (as chlorophyll a in µg/cm2), algal taxon richness, and macroinvertebrate abundance, taxonomic composition, and richness. We also estimated stream habitat and catchment characteristics, such as current velocity, shading, substrate, geology, and landuse intensity. We calculated the Akaike information criterion (AIC) for each possible multiple linear regression model to select the best predictive models for each response variable. C∶nutrient ratios were more strongly negatively related to water-column N than P availability. Neither N nor P availability covaried with periphyton biomass. Lower periphyton C∶N partly explained higher grazer, but not predator, abundance. Increased % runoff from pasture and periphyton N∶P co-occurred with a decrease in invertebrate taxon richness. For example, a 4× increase in periphyton N∶P was related to the loss of ∼½ of invertebrate species, but with high uncertainty (R2 = 0.13). We conclude landuse intensity affects these southern New Zealand streams, and these effects are mediated by agricultural N runoff into streams (among other factors). Further shifts toward high-intensity farming within stream catchments may lead to losses of benthic species at all trophic levels.