Top Of Tree Research Articles

Differences in growth between shrubs and trees: How does the stature of woody plants influence their ability to thrive in cold regions?

Shrubs can be found far above or beyond cold tree limits. However, the mechanisms shrubs employ to thrive at sites not allowing the development of trees remain poorly understood. We hypothesize that shrubs are advantaged over trees thanks to: (i) their low stature reflected in a better thermal environment; (ii) differences in temperature thresholds of wood formation; and (iii) a shorter period of wood formation in the slender stems of shrubs with narrow cells compared to tree stems with large cells. We studied wood formation of Picea abies (trees) and Pinus mugo (shrubs) growing on the same site in the treeline ecotone of the Krkonoše Mts in the Czech Republic. We measured air temperature near tree (shrub) tops, stem temperature and soil temperature in the root zone. In addition, we determined the number of cells in individual phases of wood phenology. We then computed the duration of individual wood-phenology phases and temperature thresholds for the onset of wood formation. Our results show that in the growing season, shrubs experience higher amplitude of air and stem temperatures compared to trees. Mean growing season air and stem temperatures are similar between the two growth forms whereas mean soil temperatures are lower for shrubs because their dense canopies shade the ground. Temperature thresholds for wood formation are either similar (3 °C for soil temperature, onset of cell division) or greater by 1.2–2.6 K (onset of cell enlargement) for P. mugo shrubs than for P. abies trees, depending on the temperature metrics considered. Although we found ambiguous differences in the onset of wood formation, this was completed earlier in P. mugo than in P. abies, leading to a generally shorter growing period of shrubs (103 days) than trees (125 days). In conclusion, the main advantage of shrubs over trees resides in the earlier completion of wood formation and thus a shorter growing season. Trees with wide cells at stem base require more time for cell differentiation and maturation than shrubs with narrow cells. Other differences are either of lesser importance (the ambient thermal environment) or probably species-specific (temperature thresholds for wood formation).

Сучасні проблеми створення та утримання зелених насаджень у населених пунктах України

Проаналізовано сучасні проблеми створення і утримання багаторічних зелених насаджень у населених пунктах України. Показано, що в умовах глобального потепління кліматорегулювальна роль та містотвірне і декоративне значення деревних насаджень, розташованих у містах, зростають. Встановлено, що основними чинниками, що впливають на стан багаторічних насаджень, є: старіння дерев та кущів, масове заселення багатьох видів Viscum album, самосійне поширення адвентивних видів рослин, масове порушення "Правил утримання зелених насаджень", інвазії шкідливих організмів, погіршення кліматичних умов. Існуючі проблеми зумовлені нормативно-правовими, фінансовими, організаційними, екологічними, біологічними, науковими, кадровими, культурно-історичними, ментальними причинами. Проведений аналіз причинно-наслідкових зв'язків причин і наслідків дав змогу запропонувати комплекс заходів, реалізація яких сприятиме вирішенню існуючих проблем. Зокрема запропоновано на законодавчому рівні закріпити охоронний статус міських зелених насаджень, визначити їхні площі, провести інвентаризацію та закріпити за балансокористувачами. Внесено пропозиції щодо покращення перспективного та поточного планування, поліпшення кадрового забезпечення та рівня наукових досліджень. Необхідно організувати постійний науковий моніторинг стану довкілля і насаджень як основи ефективних заходів, спрямованих на поліпшення стану насаджень. Наголошено на необхідності врахування культурно-історичних особливостей та ментальності населення різних регіонів України під час озеленення міського середовища.

Stigmata: A Memoir of Pain and Resistance

Feminist Studies 45, no. 1. © 2019 by Feminist Studies, Inc. 235 Vivyan Adair Stigmata: A Memoir of Pain and Resistance For some of us poverty is not experienced from a distance or from the position of an audience member or critic, but as the most pressing truth of our existence, past or present and our core sense of identity. —Roxanne Rimstead, Remnants of Nation: On Poverty Narratives by Women Shame My own mother—with four children under the age of seven by the time she was twenty five—taught, nurtured, and loved us ferociously but struggled and utterly failed to keep us fed, sheltered, and safe. We clung desperately to her fragile dignity, grace, and laughter, against all the forces of a cruel and indifferent world. Yet, in the end she was crushed by the weight of our shame and our raw, unrelenting pain as my brothers and sister and I were bent and broken and taken from her; with scars that never faded; injuries, infections, and ailments for which we found neither respite nor repair; with feet mangled by cheap, used Salvation Army shoes; the gnawing void of hunger and insecurity clawing at our tender backs; public indignities and humiliations for which I still can find no words. With access to neither medical insurance nor care, when my already fragile, toddling sister’s forehead was split open by a car door slammed in frustration, my brother and I had to pin her tiny body to the ground as 236 Vivyan Adair my mother sewed the angry gash together with needle and thread, practicing the meticulous dressmaker’s stitches for which she had received a modicum of acclaim, but so little reward. My sister somehow endured, but registered the pain, the terror, and the trauma with a brand, a stigmata , an angry and frightening scar as an indelible sign of our poverty, visually cleaving her very forehead in two, for the remainder of her life. In our school cafeteria “free lunchers” were reminded with a large and colorful sign to “line up last.” In that auditorium each fall we were coerced up onto a makeshift stage, with the promise of first dibs on free milk. There, our pristine school nurse sat upright and sucked air through her teeth as she donned surgical gloves to cautiously check only the hair of poor hungry children, one by one, for lice. I burned and choked and raged with shame, as our far more decent working-class colleagues and friends, in color-coordinated Sears sweater sets and matching tartan knee high socks, averted their eyes from our reluctant genuflections , while silently spooning their mac and cheese and sipping their Tree Top from tiny Dixie cups. In dilapidated and unsafe housing often without heat, hot water, or lights and with access to only public bathrooms, I developed a stubborn case of ringworm, scabies, and a series of painful urinary tract infections . When my second grade teacher would not excuse me every hour or so—because, as she said I was “willful”—I could not help but wet my pants in class. My schoolmates guffawed at my flea bitten legs, my ducttaped shoes, my crooked and ill-serviced teeth, and the way my siblings and I stank. Kids, teachers, and strangers stepped away from us intuitively and then, with great shows of distress, feigned concern and then outrage and disgust. Regularly our teachers excoriated us for our inability to concentrate in school and our refusal to come to class with proper school supplies , calling us out as greedy when we tried to take more than our share of free lunch. Whenever backpacks or library books came up missing, we were publicly interrogated and sent home to think about our offenses, often accompanied by notes that reminded my bewildered mother that she should be working twice as hard to make up for the discipline and order that had supposedly walked out the door with my father. And when occasionally we cried foul and lashed out, our behavior was used to justify even more elaborate punishment that exacerbated the effect of our growing anomie. Vivyan Adair 237 Guilt As children, our disheveled and unkempt bodies were produced as...

Evaluation of possibility of obtaining woodchips from wood residues

For the moment, the priority for the development of forestry is the provision of continuous, non-exhaustive and rational use of forest resources. In spite of this, logging residues, i.e. brushwood, twigs, tree tops, butt end and cull wood, which are unavoidably formed due to logging processes, are ploughed and burned. Analysis of this type of logging debris showed that logging residues are up to 18% of the total wood biomass and they are potential raw materials for obtaining woodchips for fuel and other types of products. The study presents evidence-based and experimentally confirmed possibility of obtaining woodchips for fiber board, pulp and paper industry. The influence of the wood species and the type of logging residues on the quality indicators of chip was established.

Stigmata: A Memoir of Pain and Resistance

Feminist Studies 45, no. 1. © 2019 by Feminist Studies, Inc. 235 Vivyan Adair Stigmata: A Memoir of Pain and Resistance For some of us poverty is not experienced from a distance or from the position of an audience member or critic, but as the most pressing truth of our existence, past or present and our core sense of identity. —Roxanne Rimstead, Remnants of Nation: On Poverty Narratives by Women Shame My own mother—with four children under the age of seven by the time she was twenty five—taught, nurtured, and loved us ferociously but struggled and utterly failed to keep us fed, sheltered, and safe. We clung desperately to her fragile dignity, grace, and laughter, against all the forces of a cruel and indifferent world. Yet, in the end she was crushed by the weight of our shame and our raw, unrelenting pain as my brothers and sister and I were bent and broken and taken from her; with scars that never faded; injuries, infections, and ailments for which we found neither respite nor repair; with feet mangled by cheap, used Salvation Army shoes; the gnawing void of hunger and insecurity clawing at our tender backs; public indignities and humiliations for which I still can find no words. With access to neither medical insurance nor care, when my already fragile, toddling sister’s forehead was split open by a car door slammed in frustration, my brother and I had to pin her tiny body to the ground as 236 Vivyan Adair my mother sewed the angry gash together with needle and thread, practicing the meticulous dressmaker’s stitches for which she had received a modicum of acclaim, but so little reward. My sister somehow endured, but registered the pain, the terror, and the trauma with a brand, a stigmata , an angry and frightening scar as an indelible sign of our poverty, visually cleaving her very forehead in two, for the remainder of her life. In our school cafeteria “free lunchers” were reminded with a large and colorful sign to “line up last.” In that auditorium each fall we were coerced up onto a makeshift stage, with the promise of first dibs on free milk. There, our pristine school nurse sat upright and sucked air through her teeth as she donned surgical gloves to cautiously check only the hair of poor hungry children, one by one, for lice. I burned and choked and raged with shame, as our far more decent working-class colleagues and friends, in color-coordinated Sears sweater sets and matching tartan knee high socks, averted their eyes from our reluctant genuflections , while silently spooning their mac and cheese and sipping their Tree Top from tiny Dixie cups. In dilapidated and unsafe housing often without heat, hot water, or lights and with access to only public bathrooms, I developed a stubborn case of ringworm, scabies, and a series of painful urinary tract infections . When my second grade teacher would not excuse me every hour or so—because, as she said I was “willful”—I could not help but wet my pants in class. My schoolmates guffawed at my flea bitten legs, my ducttaped shoes, my crooked and ill-serviced teeth, and the way my siblings and I stank. Kids, teachers, and strangers stepped away from us intuitively and then, with great shows of distress, feigned concern and then outrage and disgust. Regularly our teachers excoriated us for our inability to concentrate in school and our refusal to come to class with proper school supplies , calling us out as greedy when we tried to take more than our share of free lunch. Whenever backpacks or library books came up missing, we were publicly interrogated and sent home to think about our offenses, often accompanied by notes that reminded my bewildered mother that she should be working twice as hard to make up for the discipline and order that had supposedly walked out the door with my father. And when occasionally we cried foul and lashed out, our behavior was used to justify even more elaborate punishment that exacerbated the effect of our growing anomie. Vivyan Adair 237 Guilt As children, our disheveled and unkempt bodies were produced as...

Extractivism of palm tree fruits: A risky activity because of snakebites in the state of Acre, Western Brazilian Amazon.

We present here the risk from snakebites because of palm extractivism in western Amazonia. The data were extracted from a cross-sectional sample study, from January 2016 to April 2018, at the Juruá Regional Hospital of Cruzeiro do Sul (Acre). There were 14 Bothrops incidents involving males, most of them occurring during the harvesting of "açaí" (Euterpe precatoria). During the harvesting of "açaí," there is the risk of the presence of B. atrox on the ground near the palm tree, and of B. bilineatus at the top of the palm tree.

Marker-free coregistration of UAV and backpack LiDAR point clouds in forested areas

Unmanned aerial vehicle Laser Scanning (ULS) and Backpack Laser Scanning (BLS) are two emerging mobile mapping technologies applicable for monitoring forested environments in unprecedented detail from complementary perspectives. Although ground-based backpack techniques provide detailed information about the forest understory and terrain, the measured point clouds based on SLAM techniques are stitched together gradually and normally expressed in a less-accurate arbitrary coordinate system. Conversely, ULS point clouds are acquired from above and usually georeferenced, yet the point density and penetrability near the ground may still suffer from dense overstory despite the low attitude operation. Coregistering the ground and aerial point clouds in the ULS coordinate system therefore provides a method for fusing understory and overstory information at single tree level without the time consuming procedure of applying ground control points. Since the ULS and BLS acquisition viewpoints differ greatly, standard coregistration methods requiring 3D point-level correspondences are likely to fail. This paper presents an object-level coregistration approach which instead operates on two sets of tree positions, with the goal of finding the optimal 3D transformation (consisting of rotation, translation and scaling) between the respective coordinate systems. The entire task is decomposed into separate problems of computing the common Z axis, estimating the scale, and 2D coregistration. In contrast to existing methods, our approach does not require additional information such as tree diameters or heights. We evaluated our method on real test plots involving diverse stem densities and tree species situated in forest farm of the eastern coastal region of Jiangsu, China. The tree positions for ground and aerial data were obtained respectively by cylinder fitting and tree segmentation. On 3 coniferous (dawn redwood) plots, 46–81% trees were matched with a distance below 50 cm, and mean position deviation of 27–36 cm. For 4 broadleaf (poplar) plots, no more than 50% trees were matched below a 1 m threshold and mean error of 54–67 cm, which can be attributed to the broadleaf trees’ more irregular shape and lack of a well defined tree top. Moreover, we show that the introduction of scaling into the transform can increase the matched tree count by up to 20 percentage points and decrease the mean matched distance by up to 13% compared to a strictly rigid transform.

Ідентифікація та оцінювання висот дерев сосни звичайної у насадженнях Чорнобильської зони відчуження стереофотограмметричним способом

Розглянуто можливості використання аерофотозйомки за допомогою безпілотного літального апарату та подальшого оброблення отриманих зображень стереофотограмметричними підходами для ідентифікації дерев сосни звичайної та оцінки їх висоти у зімкнутих деревостанах способом порівняння даних, отриманих для кругової пробної площі внаслідок аерофотозйомки та в польових умовах лазерно-оптичними далекомірами, що використані як контрольні значення. Встановлено можливість ідентифікації верхівок стовбурів дерев сосни звичайної за допомогою алгоритмів пошуку максимумів растрів у програмних продуктах ГІС. Підтверджено неможливість детектування дерев нижніх елементів ярусу шляхом застосування радіусів пошуку максимумів малих розмірів (0,5 м), що спричиняє помилкову ідентифікацію значної кількості локальних максимумів (бокових гілок) як окремих дерев. Збільшення розмірів радіусу фільтрації виявлення максимальних значень растра цифрової моделі висоти крони досліджуваного деревостану до 1 м дало змогу з достатньою точністю оцінити висоту (стандартне відхилення 0,44 м) 27 дерев у верхній частині лісового пологу. Це свідчить про перспективність використання перелічених підходів для встановлення лісотаксаційних параметрів насаджень не лише з науковою метою, а й під час проведення лісовпорядкування і лісоінвентаризації, оскільки верхня висота деревостану має тісні функціональні зв'язки з іншими таксаційними ознаками.

A standardization method to disentangle environmental information from axial trends of xylem anatomical traits.

Anatomical traits such as xylem conduit diameter and vessel connectivity are fundamental characteristics of the hydraulic architecture of vascular plants. Stem xylem conduits are narrow at the stem apex, and this confers resistance to embolisms that might otherwise be induced by large, negative water potentials at the top of tall trees. Below the apex, conduits progressively widen and this characteristic minimizes effects of path length on total hydraulic resistance. While interconnections among xylem vessels have been noted for decades, their role(s) are not fully clarified. For example, we do not know if they allow water to bypass embolized vessels, or increase the risk of spread of embolisms, or how their arrangement varies within a tree. Here we demonstrate the benefit of removing the independent effect of stem length on assessment of effects of external (e.g., climatic) factors on such xylem traits. We measured the hydraulic diameter (Dh) and vessel conductivity index (VCI) along the stem of 21 shrubs/trees of similar height (1.19 < H < 5.45 m) belonging to seven Acacia species, across a wide aridity gradient in Australia. All trees showed similar scaling exponents of Dh (b = 0.33) and VCI (b = 0.53) vs axial distance from the apex (L), thus conforming with general patterns in woody plants. After de-trending for L, neither Dh (P = 0.21) nor VCI (P = 0.109) differed across the aridity gradient. We found that across a wide gradient of aridity, climate had no effect on xylem anatomy of Acacia spp, which was instead dictated by axial distances from stem apices. We argue that the use of standardization procedures to filter out intrinsic patterns of vascular traits is an essential step in assessing climate-driven modifications of xylem architecture.

Ornithology from the Tree Tops

Ornithology from the Tree Tops

Assessment of Pinus sylvestris L. tree health in urban forests at highway sides in Lithuania

Trees are often grown alongside roads in urban areas for their aesthetic and ecological values but are exposed to an array of natural and man-made stresses that impact on their overall health. The aim of this study was to determine the health of Scots pine (Pinus sylvestris L.) trees growing in urban forests alongside the Vilnius–Kaunas–Klaipėda highway in Lithuania. Long-term monitoring was conducted between 1998 and 2014, when health indicators were evaluated in 714 trees at different distances from the highway. The decrease of crown defoliation, amount of dead branches and foliage discolouration at all distances from the roadbed was detected. The results showed that trees furthest (450–500 m) from the roadbed were in better health than those growing close to the highway, exhibiting lowest crown defoliation (25.8 ± 1.6% in 1998, 12.3 ± 1.6% in 2014) compared with trees growing close to highway (47.2 ± 1.6% in 1998; 25.1 ± 1.7% in 2014), lowest foliage discolouration (14.8 ± 1.2% in 1998, 9.8 ± 0.8% in 2014), a lower amount of dead branches (14.8% ± 1.2% in 1998, 9.8% ± 0.8% in 2014) and a longer needle retention (3.2 ± 0.03 years in 2014 comparing with to 1.9 ± 0.02 close to the highway). The condition of the tree tops was good throughout the study period, with 77% of assessed trees being healthy. Statistically significant improvement in tree health was observed between 1998 and 2014, indicating an improvement in the overall health of the environment.

Mythological Image in Olonkho of the North-Eastern Yakut Tradition: Sacred Tree

The article discusses the problem of studying the North-Eastern tradition of the Yakut epic. This tradition is part of the Northern regional tradition of the Yakuts. At the moment, the problem of studying the Northern regional tradition remains open. The study was based on the works of P. Ergun, V.N. Toporov, L.V. Dmitrieva, I.V. Pukhov, N.V. Emel'yanov, L.N. Semenova and others. The images and semantics of the sacred tree in the Olonkho of the North-Eastern tradition are considered in detail. This image is characteristic for the 8 texts of the 14 considered Olonkho from momskiy, verkhoyanskiy, abyiskiy and srednekolymskiy districts or Sakha (Yakutia) Republic local traditions. In Olonkho texts of studied tradition the sacred larch image is widespread. As the researchers note, the sacred larch image is the most archaic. Carried out a comparative analysis of the sacred tree in Olonkho from three traditions (Vilyui, Central and North-Eastern). The sacred tree descriptions in the three traditions had their own regional differences. As a result of sacred tree semantics comparison in Olonkho of three traditions had been revealed the following. In the Central tradition, the sacred tree does not reach the Upper and the Lower worlds. In the Vilyui tradition, the tree penetrates through the Middle world and reaches the Upper world, becomes the horse standing for the Supreme deity Urung Ayý toyon ‘White Creator Lord’. In Olonkho of the studied tradition the top of the sacred tree goes to the Upper world and roots penetrate deep into the Lower world. In the middle world the tree Al Luk Mas appears as a center of the world and a sacred place. In the Lower world the sacred tree appears as a hook for the things of its Lord Arsan Tolaya. The main results of the work allows to suggest that the sacred tree semantics in the Olonkho of this tradition is more interesting and distinctive from the Olonkho of other regional traditions.

Relationship between stand density and value of timber assortments: a case study for Scots pine stands in north-western Poland

BackgroundStand density changes during forest growth. Various types and intensities of thinning operations can be applied in order to improve the volume of the remaining trees. It is not clear whether or not thinning results in better total volume increment although timber value is usually higher when thicker logs are obtained from trees. The objective of this study was to determine if Scots pine (Pinus sylvestris L.) stands of lower density would produce timber of a higher value than stands with a higher density and thinner trees.MethodsThe research was carried out on 20 experimental plots in 81–90-year-old Scots pine stands, located in north-western Poland. The data obtained were used to simulate the logging of the trees into either 2.5-m logs or tree tops, which were classified into five quality classes of timber. The volume of each assortment was calculated, based on its dimensions, and the value in EUR was calculated.ResultsIt was found that the correlation between stand density and the total value of the wood was very weak and not statistically significant. However, taking each assortment separately, the values of sawmill wood, pulpwood and energy wood were significantly correlated with stand density.ConclusionsIt was concluded that lower densities were more profitable for sawmill wood production, while higher densities might be more beneficial in biomass production.

Woody Debris and Nutrient Retention following Alternative Biomass Harvesting Guidelines

Concern about excessive woody debris removals during biomass harvests has led to the development of biomass harvesting guidelines (BHGs) for retaining woody debris for habitat and nutrient cycling. However, the efficacy of BHGs has not been experimentally examined. Two BHG treatments applied during clearcutting and thinning operations were examined in a replicated complete-block experiment. The first BHG treatment included the retention of one-third of tops of trees ≥8 in. dbh and one-third of trees <8-in. dbh. The second included the retention of all tops of trees ≥8-in. dbh and no restriction on the removal of smaller trees. In clearcuts, the two BHGs each increased the biomass of woody debris retained by 1.7 times compared to where no BHG was applied. However, in thinned units, there were no differences in retained woody debris regardless of BHG application. Nutrient retention trends followed those of biomass. Nutrients retained in woody debris generally exceeded nutrient removals in harvested wood except for calcium, for which removals equaled retention where BHGs were applied and exceeded retention in the absence of BHGs. Findings suggest that applying BHGs for retaining woody debris becomes more important as harvest intensity increases.

Vitality loss of European beech (Fagus sylvatica L.) and infestation by the European beech splendour beetle (Agrilus viridis L., Buprestidae, Coleoptera)

Despite its dominance in Central Europe, beech cultivation is not without risks, because drought periods and direct solar radiation of the stem are suspected of causing branch dieback, sunburn and predisposition to attack by the European beech splendour beetle Agrilus viridis. Outbreaks of this beetle occurred in Germany in the early 1950s and in Hungary between 2003 and 2006 following severe precipitation deficiencies and extraordinary high temperatures. Leaf loss and an unusual accumulation of dead branches at the top of the crown of beech trees prompted us to initiate in 2010 a three-year study to investigate whether and to what extent A. viridis infestations are involved in this damage pattern. In eight differently damaged beech stands in Bavaria (south-eastern Germany) we measured the prevalence of A. viridis with flight interception traps in relation to the vitality status of beech, checked the oviposition behaviour of females on trap trees, and investigated the infestation frequency of beech trees depending on stand structure. The prevalence of A. viridis was significantly enhanced in sample plots with more heavily damaged beech trees. At lying trap trees, females preferred parts of the bark for oviposition which had been exposed to south or west when the trees had been standing. Particularly, trees in open stands, distant to neighbours in the south and west as well as damaged by sunburn are predisposed to attack by A. viridis. It was proved that survival of A. viridis occurred in branches at the top of live beech trees from where outbreak situations may be initiated due to climatic conditions like drought and/or extreme temperatures. Prevention of A. viridis infestation consists of avoiding sudden exposure to intense solar radiation of the beech trunk by silvicultural measures.

Productivity and Costs of Two Beetle-Kill Salvage Harvesting Methods in Northern Colorado

Two ground-based timber harvesting methods have been commonly used for beetle-kill salvage treatments after a bark beetle epidemic in northern Colorado. A “lop and scatter” method uses a mobilized stroke delimber to delimb and buck trees at the stump, leaving tree tops and limbs on the forest floor, while a whole-tree harvesting method brings the entire tree to the landing where it is delimbed and bucked, and thus produces logging residue piles at the landing as a byproduct. We conducted a detailed comparative time study of the two harvesting methods to develop productivity and cost models and compared the performance of the two methods under various site conditions. We applied the productivity and cost models to lodgepole pine forest stands totaling 3400 hectares of the Colorado State Forest State Park to estimate salvage harvesting costs for each forest stand and identify the least costly harvesting options. The results show that the estimated stump-to-truck timber production costs were $30.00 per oven dry ton (odt) for lop and scatter and $23.88 odt−1 for the whole-tree method in our study harvest unit. At the forest level, the estimated average stump-to-truck costs were $54.67 odt−1 and $56.95 odt−1 for lop and scatter and whole-tree harvesting, respectively. Skidding distance and downed trees affect the harvesting costs of both methods, but their influence appears to be more significant on the whole-tree method.

A nearest neighbor approach for fruit recognition in RGB-D images based on detection of convex surfaces

Automatic fruit picking is a challenging problem in robotics with a wide application field. A prerequisite for realization of a robotic fruit picker is its ability to detect fruits in tree tops. An expert system, which would be able to compete with human perception, must be capable of recognizing fruits among leaves and branches under uncontrolled conditions, where fruits are occluded and shaded. In this paper, a novel approach for fruit recognition in RGB-D images based on detection and classification of convex surfaces is proposed. The input RGB-D image is first segmented into convex surfaces by a region growing procedure. Each convex surface is then described by an appropriate descriptor and classified with the aid of the associated descriptor. A novel descriptor of approximately convex surfaces is proposed, which we named Convex Template Instance (CTI) descriptor. It is based on approximating surfaces by convex polyhedrons with quantized face orientations, where every polyhedron face corresponds to one descriptor component. Computation of the proposed descriptor is simple and can be performed very efficiently. The proposed CTI descriptor is compared to the SHOT descriptor, a standard descriptor for 3D point clouds. Two variants of the both CTI and SHOT descriptor are evaluated, a variant which uses color and a variant which does not. A k-nearest neighbor classifier is used to classify detected surfaces into two classes: fruit and other. The main advantage of the proposed expert system in comparison to other fruit recognition solutions is its computational efficiency, which is of great importance for its target application – an automatic fruit picker. The proposed approach is evaluated using a challenging dataset containing RGB-D images of four fruit sorts acquired under uncontrolled conditions, which has been made publicly available to the scientific community, allowing benchmarking of novel fruit recognition methods.

Teores de carboidratos em mangueira Ubá submetida a diferentes doses de paclobutrazol

The use of paclobutrazol in mango tree is very widespread in the tropical regions, since they play an important role in promoting flowering, allowing production to be staggered. In addition to flowering, paclobutrazol may influence other characteristics, such as size, carbohydrate concentration and change in the green color on the leaves.The work aimed to study the possible relationship between vegetative characteristics and carbohydrate concentrations in mango plants 'Uba' submitted to different doses of paclobutrazol (PBZ). In April 2014 the PBZ was applied in mango trees ‘Uba’, conducted in factorial arrangement (5 x 2) + 1, being 5 paclobutrazol doses (0, 0.50, 1.00, 1.50 and 2.0 g (ai) per linear meter of tree top) with and without tip pruning branches. The design was randomized blocks with four repetitions and to each block was added a control treatment that has not received any of the treatments described above. It were evaluated length and diameter of the first and second budding flow, SPAD and leaf contents of starch and total soluble sugars, which samples were taken from the swelling period of gems (time 1) and 60 days after full bloom (time 2). Pruning increased growth of the first budding flow. There was no difference in the diameter of the branches in the growth of the second budding flow and SPAD. The PBZ did not affect the growth of the branches and the intensity of the green color, but changed the proportion of carbohydrates in mango trees ‘Uba’.

Top tips from tree tops

The ability of trees to cool by transporting water from their roots to the leaves has been known for centuries. But as Stephen Ornes discovers, the principles of transpiration are also inspiring innovative techniques to cool vehicles travelling at hypersonic speeds, where unwanted heat is a problem too

INTERPRETATION AT NYERI ITALIAN WAR MEMORIAL AND CULTURAL HERITAGE TOURISM: OPPORTUNITIES AND CHALLENGES.

Italian War Memorial is found in Nyeri County that is located in the colonial white highlands, characterised by rich agricultural activities in poultry farming, tea and coffee production as well as tourism activities, anchored on historical facilities namely the Tree Tops and the Ark-situated in the Aberdare national park. Kenya’s Vision 2030 has identified cultural heritage as an appropriate opportunity to promote domestic tourism and cultural pluralism, diversify tourism products and differentiate Kenya’s attractions from competitors. This can be realized by enhancing the tourism potentials of historical site like the Italian War Memorial; investing in product packaging and appropriate interpretation of resources to bring to fruition the Vision’s intent. This article sought to examine the extent to which the existing Italian War Memorial heritage resources are packaged and interpreted. Based on deductive approach, the researchers applied qualitative methods to gather and analyse information on the interpretation practices applied at the Memorial site. Findings provide information on existing interpretation infrastructures, packaging of interpretative significances, site inadequacies and stakeholders involved in the management of the memorial site. The article also provides insights on the potential negative effects related to the repatriation of mortal humans remains from Kenya to Italy. Researchers conclude that the memorial site is a potential cultural heritage tourism site that can be enhanced through appropriate interpretation infrastructures, packaging of interpretative significances and engagement of multi-stakeholders in the site’s development and management. Further the article advocates for the development of a theme that promotes an African narrative. Additionally, the paper constitutes useful academic reference material for scholars and interpreters.