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This study investigates the structural behavior of bahareque earth walls, a traditional construction system commonly used in rural areas of northern South America. Bahareque (wattle and daub) walls, consisting of guadua (a bamboo-like material) or wooden frames filled with soil mixes, have demonstrated considerable resilience in seismic zones due to their lightweight and flexible nature. Despite their widespread use in these communities, limited scientific data exist on their seismic performance under in-plane pseudo-static horizontal loading. This research addresses this gap by experimentally evaluating the seismic behavior of five wall models with different combinations of guadua, wood, and earth filling materials. The methodology included four main phases, namely field visits to document traditional construction techniques, material characterization, prototype testing under pseudo-static loads, and an analysis of mechanical behavior. Key material properties, including compressive strength and Young’s modulus, were determined, alongside the mechanical and physical properties of the infill material, which incorporated natural fibers. Pseudo-static tests were conducted on five wall prototypes, featuring various configurations of guadua and wood frameworks, both with and without soil infill. The walls were subjected to horizontal in-plane loads to assess their deformation capacity, energy dissipation, and failure mechanisms. The results indicated that walls with soil mixture infill—specifically the GSHS (guadua frame with horizontal guadua strips and soil mixture infill) and TSHS (wood frame with horizontal guadua strips and soil mixture infill) configurations—demonstrated the best seismic performance, with maximum displacements reaching up to 166 mm and strengths ranging from 6.4 to 8.4 kN. The study concludes that bahareque walls, particularly those incorporating soil mixes and horizontal guadua strips, exhibit high resilience under seismic conditions and provide a sustainable construction alternative for rural regions. The scope of this study is limited by the exclusion of dynamic seismic simulations, which could offer additional insights into the behavior of bahareque walls under real earthquake conditions. The novelty of this research lies in the direct evaluation of the seismic performance of traditional bahareque configurations, specifically comparing walls constructed with guadua and wooden frameworks, while emphasizing the critical role of soil infill and guadua strips in structural performance.

The flowering of woody bamboos has remained an enduring mystery over time. Woody bamboos can persist in a vegetative state for up to 150 years. Among these intriguing flowering bamboos are the Guadua species. Guadua, a Neotropical genus of woody bamboos, is native to the Americas and comprises 34 species. In Mexico, there are seven native species, and their flowering cycles continue to puzzle researchers. These species are primarily found in the southeastern part of the country, often along rivers and bodies of water. Presently, many of these species face threats from cattle grazing and agricultural activities, including sugarcane production. To unravel the mystery of Guadua species flowering, we conducted a thorough review of Mexico's primary herbaria and online records, complete with digital images. Through our investigation, we have identified a total of 69 flowering events spanning over a century of history for six out of the seven Guadua species in Mexico. Mexican Guadua species exhibit sporadic flowering patterns, with one species, Guadua paniculata, displaying gregarious mass flowering. Furthermore, four of the six species flower at intervals of 30–34 years. Understanding the reproductive biology of Guadua is of paramount importance for the long-term preservation of these species. Our research sheds light on one of nature's deepest secrets and underscores the critical significance of their conservation.

At present, the conservation of the environment represents an objective that everyone wants to achieve. The construction industry has influenced the advancement of alternative materials that comply with sustainable development. In this article, reinforced concrete was obtained by mixing 80% blast furnace slag and 20% fly ash. These concentrations were chosen because they provide the lowest porosity in the cementitious matrix. Rice husk ash was used as an activator. Guadua angustifolia fibers were used to evaluate the mechanical performance of the concrete. The composition of the raw material was determined by X-ray fluorescence, the microstructure of the fibers by AFM, and the SEM technique was used to determine the surface characteristics of guadua fibers and concrete mixes. The structural characterization using XRD, the structure of the molecules of the guadua fiber, and the composition of the mixture's molecular mixtures were determined by FTIR spectroscopy. Its properties, such as tensile strength and flexural strength, were analyzed. The results indicated that the concrete with the addition of Guadua angustifolia fibers. The results indicated that the concrete with the addition of guadua angustifolia fibers showed the best mechanical behavior. Tensile strength was optimized, establishing values of 2.68 MPa for unreinforced concrete and up to 3.12 MPa for fiber-reinforced concrete. The flexural strength values increase at ages after 28 days due to the pozzolanic reaction generated. Values of 2.8 MPa were obtained for concrete without fiber and 3.5 MPa for concrete reinforced with guadua angustifolia fiber. [ABSTRACT FROM AUTHOR]

Guadua weberbaueri Plig. [Poaceae] is recorded as the first host-plant record for Leptodictya (Hanuala) leinahoni (Kirkaldy). We observed eggs, nymphs, adults, and feeding injury on stands of Guadua weberbaueri, several kilometers north of the city of Caranavi, Bolivia.

Antecedentes: El bajareque es una técnica de construcción en la que se utiliza un tejido hecho con bambú, cañas, varas, mimbres, agregados con diversos compuestos de tierra local, material vegetal y agua (lodo). En México, existe evidencia arqueológica y actual del uso del bajareque en la construcción de viviendas rurales. En el sitio arqueológico de Los Guachimontones, se ha documentado el uso del bajareque con una antigüedad de 2,400 a 1,500 años, Sin embargo, se desconoce la especie de bambú utilizada. Preguntas y/o Hipótesis: 1) ¿Cuáles especies de bambú de México se han utilizado en la construcción de viviendas rurales con la técnica del bajareque? 2) ¿Cuál especie de bambú probablemente se utilizó en la construcción de viviendas con la técnica del bajareque en la zona arqueológica de Los Guachimontones, Jalisco? Resultados: Nuestros resultados indican el uso de cinco especies de bambú (Guadua amplexifolia, G. paniculata, G. velutina, Otatea acuminata y O. fimbriata) en la construcción del bajareque. Es probable que la especie utilizada en la construcción de viviendas y estructuras cívico-ceremoniales en la zona arqueológica de Los Guachimontones sea Otatea acuminata. Conclusiones: En este estudio, evidenciamos que en México se han utilizado cinco especies de bambú en la construcción del bajareque. De estas, tres pertenecen al género Guadua y dos al género Otatea. Es muy probable que en Los Guachimontones se haya utilizado Otatea acuminata en la construcción de sus viviendas con la técnica del bajareque.

Bamboo species have traditionally been used as building material and potential source of bioactive substances, as they produce a wide variety of phenolic compounds, including flavonoids and cinnamic acid derivatives that are considered biologically active. However, the effects of growth conditions such as location, altitude, climate, and soil on the metabolome of these species still need to be fully understood. This study aimed to evaluate variations in chemical composition induced by altitudinal gradient (0–3000 m) by utilizing an untargeted metabolomics approach and mapping chemical space using molecular networking analysis. We analyzed 111 samples from 12 bamboo species collected from different altitudinal ranges using liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (LC-QTOF-MS). We used multivariate and univariate statistical analyses to identify the metabolites that showed significant differences in the altitude environments. Additionally, we used the Global Natural Products Social Molecular Networking (GNPS) web platform to perform chemical mapping by comparing the metabolome among the studied species and the reference spectra from its database. The results showed 89 differential metabolites between the altitudinal ranges investigated, wherein high altitude environments significantly increased the profile of flavonoids. While, low altitude environments significantly boosted the profile of cinnamic acid derivatives, particularly caffeoylquinic acids (CQAs). MolNetEnhancer networks confirmed the same differential molecular families already found, revealing metabolic diversity. Overall, this study provides the first report of variations induced by altitude in the chemical profile of bamboo species. The findings may possess fascinating active biological properties, thus offering an alternative use for bamboo.

In this study, compression mechanical properties of five giant bamboo species from different continents were investigated based on the ISO 22157:2019 standard. The selected species have been used for rural construction for centuries. The chosen bamboo species for this study, which are considered strong candidates to be used in modern construction as well, are as follows: Phyllostachys edulis (Moso), Guadua angustifolia (Guadua), Gigantochloa apus (Tali), Gigantochloa atroviolacea (Black Java), and Phyllostachys bambusoides (Madake). The excellent properties of bamboo species in tension are well established. Hence, this article principally focuses on the behaviour of selected giant species in compression to be used as structural members. In this study, the mentioned bamboo species were gathered from different continents of origin to be critically assessed, analysed, and compared with one another to better understand their compression behaviour as structural columns. The compression properties of these bamboo species have not been evaluated and compared with one another in an academic study so far. The results show that all tested species were able to provide mean compressive strengths greater than 50 MPa, which makes them highly promising construction material candidates for modern construction. The Guadua test series was able to provide outstanding consistency in the presented compression behaviour and strengths among all the tested species. The specimens with the maximum sustained load belonged to the Tali species. The greatest average failure load belonged to the Moso species. The greatest mean compressive strength measured was 88.9 MPa, reported for Madake species with smaller diameters compared to the other test series. Among the specimens with larger diameters, the greatest mean ultimate strengths were for Moso, Guadua, and Tali species with 69.9 MPa, 60.7 MPa, and 59.1 MPa compressive strengths, respectively. [ABSTRACT FROM AUTHOR]

Republican masonry is part of the historical heritage of Latin America. However, their behavior in seismic events is not optimal, therefore the conservation of these constructions should consider the improvement of their structural behavior. This research studies the reinforcement with Guadua bamboo mat and analyzes its structural incidence in walls built with units recovered from republican constructions. For the experimental process, walls were built for compression and diagonal tension tests, classified in three groups: walls without reinforcement, walls reinforced with guadua mat, and walls reinforced with guadua mat covered with lime mortar and metakaolin. In the tests, although no increase in strength was observed in the reinforced walls, an increase in strain and ductility was observed. Therefore, the guadua mat represents a viable alternative to improve the behavior of republican structures in seismic events. [ABSTRACT FROM AUTHOR]

The use of guadua has increased in importance as a construction material due to the implementation of sustainable materials in the construction sector. This material provides a good view to passersby of the typical mountainous landscapes of eastern Antioquia in Colombia. Furthermore, bridges are fundamental structures for connecting territories separated by streams, roads, or topographic depressions. The methodology of this research work considers in the first step the bibliographic compilation, the second step the main physical and mechanical properties of the guadua/bamboo, the three-step the analysis of the points and connections, and finally, the last step four the architectural design appropriately a structure that can be used as a Pedestrian Bridge in Antioquia in the most faraway locations. Also, specialized design software was used to obtain the conceptual design of the components and geometrical areas of the bridge and thus consider its use in real conditions. This works aims to present an architectural solution consisting of a bridge with a span of 12 m considering as the main component guadua Angustifolia elements that are interconnected design with metal elements being as support to obtain adequate and ecological structural characteristics contributing to the development of the sustainability in the civil engineering projects. Finally, the results exposed that considering the literature review and research consulted, it is possible to design a bridge with the appropriate structural conditions. It's important to mention that this work was carried out from the architectural and functional point of view of the structure, prioritizing aesthetic and urban aspects, for which it is necessary to carry out structural modeling, obtaining the design parameters from laboratory tests on the guadua species of the zone. [ABSTRACT FROM AUTHOR]

The need for social housing creates challenges for engineering. One of the most economical and ecological structural systems for certain areas is the cemented bahareque, which uses Guadua cane, a type of Bamboo with favorable properties for construction. Despite being an ancient technique for the construction of houses, there is not an extensive bibliography that allows making justified decisions regarding their design in most cases. One of the objectives of this article is to present a prototypical design of a housing case with appropriate characteristics to allow a decent occupant’s life with this construction system. For the selected house, the structural behavior is evaluated under gravitational and seismic loads. The constructive criteria that will provide good performance under seismic events are recommended. The most important criteria to follow for the design of wall systems are regularity, continuity, symmetry, bolted connections, rigid diaphragms for mezzanines and continuous maintenance of the Guadua cane elements that make up the framework of the walls. Finally, it is concluded that following the basic criteria of earthquake-resistant design for this type of housing, adequate structural performance can be obtained.

Abstract Bamboos are productive grasses that currently yield a high‐quality wood and potentially an abundance of lignocellulose for bioenergy. All are C3 grasses of warm habitats, where they are prone to significant photorespiratory inhibition and competitive suppression by C4 grasses. Here, we investigate whether three bamboo species from the Brazilian Cerrado (Dendrocalamus asper, Guadua angustifolia, and Guadua magna) exhibit unique adaptations that suppress photorespiratory costs and enhance photosynthetic efficiency. We evaluated photosynthetic efficiency of the bamboos and rice (Oryza sativa) by measuring C*, the CO2 compensation point in the absence of mitochondrial respiration. At 25℃, C* averaged 2.81 Pa in each of the bamboo species, which is closer to a C2 plant (2.71 Pa) than the C3 plant rice (3.31 Pa). Assuming a chloroplast CO2 concentration of 200 µmol mol−1, this represents an 18% lower cost of apparent photorespiration in bamboo than rice. Light and transmission electronic microscopy of the bamboo leaves exhibited few organelles in the bundle and mestome sheath cells, and mesophyll (M) cells are deeply lobed with 99% of the cell periphery adjacent to intercellular air space covered by chloroplast and stromules. The chloroplast layer in bamboo M cells is thick, with mitochondria adjacent to or engulfed by chloroplasts. This arrangement slows CO2 efflux and facilitates refixation of photorespired CO2, which could explain the low C* in the bamboos. The bamboos also had higher water use efficiency than rice, which may reflect efficient refixation of photorespired CO2.

ABSTRACT Although karyotype features are useful data for evolutionary studies, cytogenetic data in Bambusoideae are mainly based only on chromosome counts. The first comparative cytogenetic analysis of three Neotropical woody bamboo species - Guadua chacoensis, G. angustifolia and Chusquea tenella - was undertaken based on new and reviewed chromosome counts, CMA/DAPI double staining, fluorescent in situ hybridization (FISH) with 35S and 5S rDNA probes, and genome size estimation. The two species of Guadua were found to have 2n = 46 chromosomes, while the first record for C. tenella was 2n = 44. Only one pair of CMA+/DAPI- was detected on the terminal region of metacentric chromosomes in all three species. Likewise, one pair of 5S and 35S rDNA sites was detected in all three species, with the 35S rDNA sites always collocated with the CMA+ bands. Genome sizes ranged from 2C ≈ 3.99 pg for the species of Guadua, to 2C = 4.77 pg for C. tenella. Considering the Miocene origin of Neotropical woody bamboos, the observed karyotype stability suggests that the analyzed species are diploidized paleopolyploids. The results reveal the conservative cytomolecular organization of Neotropical woody bamboo karyotypes, which helps to improve our understanding of the evolution of this group.

El estudio describe y analiza los costos de uniones empleadas en la construcción con bambú rollizo, tanto modelos convencionales como uniones de innovación desarrolladas para reducir los tiempos de ejecución y facilitar los procesos de trabajo. Los resultados son insumos esenciales para la elaboración de metrados y presupuestos de estructuras de bambú y ofrecen valores comparativos para guiar la toma de decisión en el diseño.

En la Región San Martín existe una confusión en torno a la identificación de tres especies del género Guadua. Según la distribución y las características morfológicas se determina que “Kunth” procedente de La Florida (provincia de San Miguel, Región Cajamarca) corresponde a Guadua angustifolia Kunth, “Marona” procedente de Atumplaya (provincia de Moyobamba, Región San Martín) corresponde a Guadua lynnclarkiae Londoño, y “Guayaquil” procedente de la Región San Martín es definida como Guadua sp. al no tener identificación taxonómica definida. Mediante el análisis morfológico y molecular se identifican las variables morfológicas y moleculares que permiten la discriminación de las especies en estudio. El análisis morfológico se realizó en Guadua sp. y Guadua lynnclarkiae y consistió en mediciones diarias de altura de la planta, distancia entre nudos, número de nudos, número de ramificaciones, número de hojas, color de hojas (verdes claras o de color anaranjado) y diámetro, durante un mes. El análisis molecular fue realizado en las tres especies estudiadas, se extrajo el ADN para posteriormente realizar la amplificación de este por medio de la técnica ISSR. Los iniciadores ISSR utilizados fueron: IS-5, SSR 15, SSR 16 y SSR 22. Las variables morfológicas que permitieron diferenciar a las especies Guadua sp. y Guadua lynnclarkiae fueron la “altura” y “número de hojas”. Mientras que, el iniciador IS-5 permite discriminar a Guadua sp. de Guadua lynnclarkiae y Guadua angustifolia. Los iniciadores SSR 15, SSR 16 y SSR22 no permitieron diferenciar a las especies en estudio.

Resumen Este estudio muestra un sistema constructivo alternativo para Vivienda de Interés Social (VIS). Su aplicación ha sido prevista para la ciudad de Guayaquil pero con potencial para ser replicada a nivel de la costa ecuatoriana con el objetivo de disminuir el déficit habitacional actual en el país. El resultado es un sistema prefabricado modular a base de una tipología de panel machihembra-do de 4cm de espesor, que combina las propiedades de la Guadua angustifolia kunth empleada como esterilla, con el mortero con Ceniza de Cáscara de Arroz reforzado con una malla electrosoldada de acero de 5.5 mm y 20 cm de separación. El mortero ha sido microvibrado en una mesa equipada con un motor de 3500 RPM y contrapeso excéntrico de 30 gr con el objetivo de mejorar la adherencia del mortero a la esterilla y evitar fisuras. Abstract This study shows an alternative constructive system for Social Interaction Housing (VIS). Its application has been planned for the city of Guayaquil but with the potential to be replicated at the level of the Ecuadorian coast with the aim of reducing the current housing deficit in the country. The result is a modular prefabricated system based on a 4 cm thick tongue-and-groove type panel, which combines the properties of the Guadua angustifolia kunth used as a mat, with the mortar with Ash of Rice Shell reinforced with an electrowelded mesh of 5.5 mm steel and 20 cm separation. The mortar has been microvibrated in a table equipped with a 3500 RPM motor and 30 gr eccentric counterweight to improve the adhesion of the mortar to the mat and to avoid fissures.

Mixed-species flocks of birds are cohesive groups of two or more different species that are kept in formation by systematic behavioral interactions among the members of the flocks. Typically, mixed-species flocks form themselves around a nuclear species, which presents a specific pattern of movement during foraging, and a song that is recognized by the other species. In the understory of Neotropical forests, representatives of the family Thamnophilidae, in particular species of the genus Thamnomanes, have become adapted for the role of nuclear species in mixed-species flocks. In the present study, we describe the mixed-species flocks led by individuals of Bluish-slate Antshrike Thamnomanes schistogynus in a forest dominated by bamboo Guadua sp. in southwestern Brazilian Amazonia. We collected data within a 600 × 600 m grid subdivided into 36 1-ha plots, with a total area of 36 ha. Within this grid, we delimited the home ranges and core areas of the resident mixed-species flocks. We also identified the composition of each flocks, frequency, fidelity of its members and determined the relationship between mixed-species flocks and vegetation structure within the grid. We delimited the home ranges of eight mixed-species flocks. The mean home range, estimated using the Minimum Convex Polygon method, was 3.45 ± 0.17 ha, and estimated using the autocorrelated kernel density estimation method was 3.65 ± 0.15 ha, and the mean core area, 1.14 ± 0.03 ha. The home ranges of the mixed-species flocks led by T. schistogynus in southwestern Amazonia are among the smallest recorded in species of the genus Thamnomanes. We identified 71 different bird species in the mixed-species flocks with a mean of 41.1 ± 2.1. While the geographic distribution of the lead species T. schistogynus coincides almost exactly with that of the bamboo forests of southwestern Amazonia, our results did not indicate any systematic relationship or fidelity between the mixed-species flocks led by this species and the bamboo forest. [ABSTRACT FROM AUTHOR]

Bamboos are productive grasses that currently yield a high‐quality wood and potentially an abundance of lignocellulose for bioenergy. All are C3 grasses of warm habitats, where they are prone to significant photorespiratory inhibition and competitive suppression by C4 grasses. Here, we investigate whether three bamboo species from the Brazilian Cerrado (Dendrocalamus asper, Guadua angustifolia, and Guadua magna) exhibit unique adaptations that suppress photorespiratory costs and enhance photosynthetic efficiency. We evaluated photosynthetic efficiency of the bamboos and rice (Oryza sativa) by measuring C*, the CO2 compensation point in the absence of mitochondrial respiration. At 25℃, C* averaged 2.81 Pa in each of the bamboo species, which is closer to a C2 plant (2.71 Pa) than the C3 plant rice (3.31 Pa). Assuming a chloroplast CO2 concentration of 200 µmol mol−1, this represents an 18% lower cost of apparent photorespiration in bamboo than rice. Light and transmission electronic microscopy of the bamboo leaves exhibited few organelles in the bundle and mestome sheath cells, and mesophyll (M) cells are deeply lobed with 99% of the cell periphery adjacent to intercellular air space covered by chloroplast and stromules. The chloroplast layer in bamboo M cells is thick, with mitochondria adjacent to or engulfed by chloroplasts. This arrangement slows CO2 efflux and facilitates refixation of photorespired CO2, which could explain the low C* in the bamboos. The bamboos also had higher water use efficiency than rice, which may reflect efficient refixation of photorespired CO2. [ABSTRACT FROM AUTHOR]

The Brazilian state of Acre has an extensive natural reserve of bamboo, making it one of the largest in loco gene banks. The aim of this study was to characterize the structure and genetic diversity of Guadua weberbaueri Pilg. in two populations, one native (FAPB) and the other anthropized (FAPBA), using ISSR markers. The results show that the FAPB population exhibited higher values for all estimates of population diversity. However, the FAPBA population also showed high heterozygosity, corroborated by estimated gene flow (Nm = 3.9) between the populations. The study of the association between Nei's genetic distances and the geographic distances between the populations were significantly correlated (r = 0.45, p = 0.01), corroborated by the dendrogram revealing two distinct groups corresponding to the collection sites, without mixing classes between populations in the same group. As for the coancestry coefficient, pairs of individuals in the first distance class were positive and significant, indicating that plants that are geographically closer share common alleles with a frequency greater than by chance, which means that there is a tendency that geographically closer individuals are related. Individuals presented similar genetic structure when the geographical distance between them was up to 56 m for FAPB and up to 156 m for FAPBA. It was concluded that anthropized environments exhibit less genetic diversity than native environments, inferring risks for species conservation if appropriate and planned management techniques are not adopted. [ABSTRACT FROM AUTHOR]

Bamboo‐dominated forests (BDF) extend over large areas in the drought‐prone Southwestern Amazon, yet little is known about the dynamics of these ecosystems. Here, we investigate the hypothesis that bamboo modulates large‐scale ecosystem dynamics through competition with coexisting trees for water.We examined spatio‐temporal patterns of remotely sensed metrics (Enhanced Vegetation Index [EVI], Normalized Difference Moisture Index [NDMI]) in >300 Landsat images as proxies for canopy leaf phenology and water content at two time scales: (1) a complete bamboo life cycle (~28 years), and (2) the seasonal cycle; and at two spatial scales: (a) comparing adjacent areas of BDF vs. Terra‐firme forests (TFF) to investigate regional dynamics, and (b) comparing the vegetation classes of bamboo, trees in BDF, and trees in TFF to investigate the effects of bamboo on coexisting trees.At the regional scale, BDF showed higher EVI (leaf area density) and lower NDMI (water content) than nearby TFF but these differences disappeared as bamboo died, suggesting a strong influence of bamboo life stage in the functioning of these forests. BDF seasonal cycle showed a bimodal EVI pattern as trees and bamboos had asynchronized leaf production peaks.At the scale of vegetation classes, trees in BDF showed lower NDMI (i.e. water content) than trees in TFF except after bamboo mortality, indicating a release from competition with bamboo for water. Canopy water content of trees in BDF was also reduced during bamboo dry‐season greening (increased EVI ~ leaf production) due to increased water demands. Nevertheless, long‐term and seasonal phenology of trees in BDF did not differ from that of trees in TFF suggesting a potential selection for drought‐tolerant trees in BDF.Synthesis. Bamboo‐dominated forests have received less attention than other Amazonian forests and their functional dynamics are commonly ignored or misinterpreted. Using remote sensing to characterize forest phenology and water content, we show the distinctive seasonal and long‐term dynamics of BDF and coexisting trees and the importance of bamboo competition for water in shaping this ecosystem. Our results suggest a potential selection for drought‐tolerant trees in BDF since they maintain the same EVI as trees in bamboo‐free forests but with lower water content. A better characterization of BDF and their cyclical dynamics is crucial for accurately interpreting Amazonian forests' responses to extreme climatic events such as high temperatures and droughts. [ABSTRACT FROM AUTHOR]

Abstract The Southwestern Region of the Brazilian Amazon is formed by forests dominated by bamboos. The genus Guadua is endemic to the Americas, and little is known about the genetic diversity and structure of species of this genus. This study aimed to evaluate the genetic diversity and structure of two native Guadua species in natural populations in the Southwestern region of the Brazilian Amazon. Therefore, the genetic diversity and structure of Guadua aff. chaparensis and Guadua aff. lynnclarkiae were evaluated with the use of microsatellite molecular markers (SSR). It was verified that the average genetic diversity for the populations studied was considered high ( H ^ e =0.5) compared to other species of bamboo. All populations had rare and private alleles, and none of them presented significant values of inbreeding. The populations were divergent ( G ^ ST = 0.46), resulting in a low apparent gene flow. The Bayesian analysis showed that among the 350 individuals analyzed, five groups (K=5) were formed, with little similarity among the groups (Populations), although two of them presented clonal individuals. According to the results obtained, it can be conclude that populations should be treated as having unique characteristics, mainly when accessed for management and for in situ and ex situ conservation studies.

Bamboos are known for their economical, ecological, and cultural importance. The plants can be annual or perennial and can be herbs, shrubs or trees and can also show different growth habits. The cell wall is the main component of the mechanical properties of the tissues. Data set presented here contains the results of cell walls fractioning of culms from six neotropical bamboo species: Apoclada simplex, Chusquea capituliflora, Filgueirasia arenicola, Filgueirasia cannavieira, Guadua tagoara, Merostachys riedeliana and Parodiolyra micrantha. The cell walls were fractionated with oxalate and increasing NaOH concentrations sequentially. The yield and the monosaccharide compositions showed a small amount of pectin as expected for Poaceae and arabinoxylan as the main hemicellulose. The digestion of the hemicellulose fraction with xylanase produced an oligosaccharide profile that could be used to compare the similarity of the arabinoxylan from different species without identifying each individual oligosaccharide. Our data showed that the differences in cell wall composition do not vary according to the growth habit, but are in close association with the phylogenetic relations within the family. The differences in load capacity in plants with different habits (trees and herbs, for example) are more associated with the amount of support tissues than with different cell wall compositions. The importance of evaluate the cell wall of tropical bamboo species aimed at improving resources for biotechnology was discussed by Tine et al. 2020 [1].

With the increasing of problems related to air pollution and rising of the mean temperature around the globe, new solutions must be investigated in order to diminish the magnitude of such environmental issues. Therefore, the appliance of bamboo in the construction can be one of the solutions. Even though, this grass does not present mechanical or thermal homogeneity, its high sustainability (CO2 reducer, highness and fast speed of growth), strength and hollowed cylindrical morphology make it an option in the construction sector. As an energy-efficient material, this woody grass can have a positive thermal performance due to the presence of air cavities, however, its rounded nature influence to a nonhomogeneous performances in the surface and interior. The literature about the thermal performance of this element as building envelopment is reduced. Thus, the aim of this research is to analyse the thermal performance of a one, two and three bamboo layers, placing them in a way to mitigate the heat leaking and improving the thermal resistance. It is analysed numerically and through a simulation developed in THERM 7.5 Finite Element Simulator. As a result, two line of bamboo is convenient as a material construction with U-Value of 1.4 W/m².K, but three layers is recommended to mitigate the presence of thermal bridges. The results obtained leads to a different approach and suggests further analysis for different parameters.

Questions: Does the floristic composition of trees differ between bamboo forests and adjacent non‐bamboo forests? Can the degree of compositional differences be predicted from differences in canopy reflectance as measured by Landsat satellites? Are the results sensitive to different taxonomical data cleaning strategies, or to which tree‐size class is considered? Are some tree taxa associated with either bamboo or non‐bamboo forests? Location: Peruvian Amazonia. Methods: We used national forestry inventory data to characterise floristic composition of trees at 25 sites. Bamboo and non‐bamboo forests were identified with a pixel‐based time series analysis using the entire Landsat TM/ETM+ archive. To visualise floristic similarity among the plots, we used non‐metric multidimensional scaling. Floristic differences between bamboo and non‐bamboo forests were tested using an analysis of similarity (ANOSIM). Mantel tests were used to assess correlation between floristic turnover and differences in canopy reflectance. We tested the impact of applying three different taxonomic data cleaning strategies and of analysing different tree‐size classes. Finally, we ran an indicator species analysis to identify taxa that were associated with either bamboo or non‐bamboo forests. Results: In floristic ordinations, bamboo‐dominated forests appeared floristically distinct from non‐bamboo forests regardless of the taxonomic cleaning strategy and tree‐size class. This floristic separation was also confirmed through analysis of floristic similarity (ANOSIM). Turnover in floristic composition was strongly correlated with differences in the reflectance values of Landsat bands, especially when using genus‐level rather than species‐level data. Different palm taxa were associated with bamboo (Socratea) and non‐bamboo forests (Iriartea). Conclusions: Floristic differences of trees between bamboo‐dominated and non‐bamboo forests are consistent enough to be observable with different tree‐size classes and taxonomic cleaning strategies. Although coarsening the taxonomic resolution to the genus level may hide ecological detail from the results, the fact that it allows keeping incompletely identified stems in the analyses seems to compensate for this. [ABSTRACT FROM AUTHOR]

About 160 000 km2 of forests in the border zone between Brazil and Peru are dominated by semi-scandent bamboos (Guadua spp.). We argue that both predicted decreased precipitation during the dry season and widespread anthropogenic disturbances will significantly increase the distribution and biomass of bamboos in the area. Seasonal dryness favours the growth of evergreen bamboos in relation to trees that shed their leaves during the dry season. Disturbance can be beneficial for the bamboo because, as a clonal plant, it is often able to recover more rapidly than trees. It also withstands dry season better than many trees. The bamboo life cycle ends in a mass mortality event every 28 years, producing potential fuel for a forest fire. Presently, natural forest fires hardly exist in the area. However, in the projected future climate with more pronounced dry season and with increased fuel load after bamboo die-off events the forests may start to catch fire that has escaped from inhabited areas or even started naturally. Fires can kill trees, thus further increasing the fuel load of the forest. As a result, the landscape may start to convert to a savanna ecosystem. [ABSTRACT FROM AUTHOR]

We studied phytoliths (plant stones) from 228 leaf samples of Guadua weberbaueri and Guadua sarcocarpa bamboos from eleven collection locations in Southern Peruvian Amazonia and in the state of Acre in Brazil. Four leaf-blade transverse thin sections were made by grinding and smoothing them into a 30 µm thickness, and over 550 phytolith slides created by using both the dry ashing and wet oxidation methods. Large-sized (up to 50 µm) cuneiform bulliform cells in the intercostal adaxial leaf-blade areas were the most conspicuous phytoliths in Guadua leaves, but their abundance varied even locally. Other recurrent phytolith types included bilobate, saddle, and rondel shaped short cells; long cells in many different sizes and ornamentations; and prickle hairs, spikes, stomatal, and inter-stomatal cells. We found the definite classification of phytoliths into morphotypes difficult because of their variable sizes, forms, and surface characteristics. Conjoined tricellular cell structures with one to three mineral-accumulating cells forming a characteristic mushroom-like constellation were also documented. Fusoid cells forming dense rows attached to the costal zones locally showed mineralization, indicating their role in inorganic mineral mobilization and deposition in Guadua leaves. Foliar phytolith assemblages showed little variation among the different collection locations compared to the variation found among leaves within individual sites. [ABSTRACT FROM AUTHOR]

Highlights • Influence of delignification of bamboo fibers on the physical and mechanical properties. • Fibers treated with methane cold plasma showed greater roughness. • Plasma treatment reduce the absorption capacity of the fibers. • Panels made with fibers treated with plasma exhibited an increase in the dimensional stability. Abstract The influence of the process of delignification of bamboo fibers on the physical and mechanical properties of panels made with Guadua fibers and a plant polyurethane was studied. The modification of the fiber surfaces was carried out by means of a chemical method and a physical one. The chemical method consisted of the application of an alkaline treatment, varying the concentrations of sodium hydroxide (10% and 20%). The physical method consisted of a treatment with methane cold plasma. Manual molding and compaction by the pressing method was used for the construction of the panels. The physical properties of the composites were evaluated by the determination of their relative density, effective absorption, and percentage of swelling. In order to evaluate the mechanical properties, tensile, compression, and three-point static bending tests were performed. Panels made with fibers treated with methane cold plasma exhibited a notable reduction in the effective absorption capacity, greater dimensional stability, and better mechanical performance. [ABSTRACT FROM AUTHOR]

The aim of this research is to design an architectural and habitation proposal to provide improvement with the housing in waterfront of San Andres de Tumaco (Nariño), especially in "bajamar" zone. The research has been carried out on the dynamic behavior of families and neighborhood, considering the social, cultural and physical features at the study zone. The study approaches the innovation in habitational solution from the community way of life. The analysis of social map, interviews and participating design were used to characterize the Pacific zone in Colombia. The culture is considered the central concept in the architectural design, joining with the environment and the features of the pacific zone. Those characterizations help to provide habitation solution, energy solutions, waste management, and support among the neighbors. [ABSTRACT FROM AUTHOR]

Three connection design properties (dowel embedment strength, slip modulus and screw withdrawal capacity) were determined for one species of bamboo ( Guadua angustifolia Kunth) using experimental methods adopted from timber engineering. 151 embedment strength and slip modulus tests were undertaken using smooth dowels with diameters ranging from 3 to 16 mm, whilst 240 screw withdrawal tests were undertaken using 3.5–5 mm diameter self-tapping screws. Using regression analysis, predictive equations for the three connection design properties were derived, based on fastener diameter, density and bamboo wall thickness. Coefficients of determination (R 2 ) ranged from 0.45 to 0.82. The predictive equations for embedment strength and screw withdrawal were adapted to output characteristic values and then compared to similar equations derived for timber contained in Eurocode 5, the latter would seem inappropriate for bamboo. [ABSTRACT FROM AUTHOR]

El propósito de esta investigación es hacer una comparación de la productividad de los corteros de guadua, tras la implementación del método de cosecha actual frente a la propuesta de un método de cosecha mejorado, a partir de la introducción de elementos de la administración científica. El estudio se hizo en dos cuadrillas y en cada una se observaron corteros en diferentes áreas hasta completar una muestra igual a 10 operarios. Como resultado del análisis, se concluye que los causantes externos de demoras son la presencia de ganchos con más de un metro de longitud, vegetación menor, guaduas secas, guaduas fallas; y que, por eliminar dichos causantes se puede aumentar la productividad de cada cortero en aproximadamente un 12,9 %.

In this work, the condensable gases of the bio-oil produced from its fast pyrolysis at 500 ºC for 30 s has been analyzed by Py-GC/MS. Relatively high yields of acetic acid, phenolics and levoglucosan have been found. Levoglucosan can be used as a source for synthesizing bio-fuels and both, phenolics and levoglucosan in the production of chemicals. However, further research is necessary in order to find adequate ways of using the great potential of this type of lignocellulosic biomass for developing a bio-based economy less dependent on fossil fuels and more respectful with the environment. [ABSTRACT FROM AUTHOR]