Effect of pruning on tree growth, yield, and wood properties of Tectona grandis plantations in Costa Rica

Abstract

2012 Community Tree Management Plan, Alburnett, IA, June 24, 2013

This plan was developed to assist Alburnett with the management, budgeting and future planning of their urban forest. Across the state, forestry budgets continue to decrease with more and more of that money spent on tree removal. With the anticipated arrival of Emerald Ash Borer (EAB), an invasive pest that kills native ash trees, it is time to prepare for the increased costs of tree removal and replacement planting. With proper planning and management of the current canopy in Alburnett, these costs can be extended over years and public safety issues from dead and dying ash trees mitigated. Trees are an important component of Alburnett’s infrastructure and one of the greatest assets to the community. The benefits of trees are immense. Trees provide the community with improved air quality, stormwater runoff interception, energy conservation, lower traffic speeds, increased property values, reduced crime, improved mental health and create a desirable place to live, to name just a few benefits. It is essential that these benefits be maintained for the people of Alburnett and future generations through good urban forestry management. Good urban forestry management involves setting goals and developing management strategies to achieve these goals. An essential part of developing management strategies is a comprehensive public tree inventory. The inventory supplies information that will be used for maintenance, removal schedules, tree planting and budgeting. Basing actions on this information will help meet Alburnett’s urban forestry goals.

2012 Community Tree Management Plan, Avoca, IA, May 2, 2013

This plan was developed to assist Avoca with the management, budgeting and future planning of their urban forest. Across the state, forestry budgets continue to decrease with more and more of that money spent on tree removal. With the anticipated arrival of Emerald Ash Borer (EAB), an invasive pest that kills native ash trees, it is time to prepare for the increased costs of tree removal and replacement planting. With proper planning and management of the current canopy in Avoca, these costs can be extended over years and public safety issues from dead and dying ash trees mitigated. Trees are an important component of Avoca’s infrastructure and one of the greatest assets to the community. The benefits of trees are immense. Trees provide the community with improved air quality, stormwater runoff interception, energy conservation, lower traffic speeds, increased property values, reduced crime, improved mental health and create a desirable place to live, to name just a few benefits. It is essential that these benefits be maintained for the people of Avoca and future generations through good urban forestry management. Good urban forestry management involves setting goals and developing management strategies to achieve these goals. An essential part of developing management strategies is a comprehensive public tree inventory. The inventory supplies information that will be used for maintenance, removal schedules, tree planting and budgeting. Basing actions on this information will help meet Avoca’s urban forestry goals.

2012 Community Tree Management Plan, Belle Plaine, IA, June 24, 2013

This plan was developed to assist Belle Plaine with the management, budgeting and future planning of their urban forest. Across the state, forestry budgets continue to decrease with more and more of that money spent on tree removal. With the anticipated arrival of Emerald Ash Borer (EAB), an invasive pest that kills native ash trees, it is time to prepare for the increased costs of tree removal and replacement planting. With proper planning and management of the current canopy in Belle Plaine, these costs can be extended over years and public safety issues from dead and dying ash trees mitigated. Trees are an important component of Belle Plaine’s infrastructure and one of the greatest assets to the community. The benefits of trees are immense. Trees provide the community with improved air quality, stormwater runoff interception, energy conservation, lower traffic speeds, increased property values, reduced crime, improved mental health and create a desirable place to live, to name just a few benefits. It is essential that these benefits be maintained for the people of Belle Plaine and future generations through good urban forestry management. Good urban forestry management involves setting goals and developing management strategies to achieve these goals. An essential part of developing management strategies is a comprehensive public tree inventory. The inventory supplies information that will be used for maintenance, removal schedules, tree planting and budgeting. Basing actions on this information will help meet Belle Plaine’s urban forestry goals.

Mycorrhizal dependency of mangaba tree under increasing phosphorus levels

The objective of this study was to evaluate the mycorrhizal dependency of mangaba tree (Hancornia speciosa) plantlets, under increasing levels of phosphorus fertilization. The experimental design was completely randomized in a 4×5 factorial arrangement with three mycorrhizal fungi inocula - Gigaspora margarita, Glomus etunicatum, or a pool of native mycorrhizal fungi (Acaulospora longula, Glomus clarum, Gigaspora albida, Paraglomus sp.) -, and a nonmycorrhizal control, in combination with five levels of phosphorus applied to the substrate: 0, 25, 50, 75, and 100 mg kg-1. After 180 days of growth, plantlets with inoculation of native mycorrhizal pool produced more shoot and root dry biomass and had higher shoot phosphorus content and accumulation. The noninoculated control showed the lowest values, independently of the phosphorus level. The highest relative mycorrhizal dependency occurred with the inoculation of native mycorrhizal fungi. Plants with mycorrhizal fungi did not respond to phosphorus addition above 50 mg kg-1. Mangaba tree is highly dependent on mycorrhiza, but the degree of dependency varies according to phosphorus levels and fungal inocula. In general, mangaba tree is more responsive to mycorrhizal fungi inoculation than to phosphorus addition.

Variabilidade genética estimada entre diplóides de banana por meio de marcadores microssatélites

O objetivo deste trabalho foi estimar a divergência genética entre 38 diplóides de banana do programa de melhoramento da Embrapa Mandioca e Fruticultura Tropical, incluindo genótipos melhorados, cultivados e selvagens, por meio de 15 marcadores microssatélites ou SSR. As similaridades genéticas, com base no coeficiente de Jaccard, foram utilizadas para fazer o agrupamento dos genótipos pelo método UPGMA. O número de alelos obtidos foi 113, com média de 7,53 alelos por iniciador. A similaridade genética média foi de 0,22, e variou de 0,028 a 0,48, o que indica existência de variabilidade genética entre os genótipos. A análise de grupos, com base no polimorfismo de microssatélites, não pôde separar completamente os híbridos melhorados, cultivados e selvagens. Alguns diplóides agruparam-se com base em sua origem geográfica, entre eles Musa ornata e IAC-1, e Tjau Lagada e Lidi, enquanto que, em outros, nenhuma relação foi estabelecida. Houve tendência de agrupamento entre os diplóides aparentados, como: SH3263 e 8694-20, 4279-01 e 9179-03, 1304-06 e 5854-03, 86B79-10 e 7341-03, 86B79-12 e 0337-02, e 9194-04 e 4154-08.

Density, climate and varying return points: an analysis of long-term population fluctuations in the threatened European tree frog.

Experimental research has identified many putative agents of amphibian decline, yet the population-level consequences of these agents remain unknown, owing to lack of information on compensatory density dependence in natural populations. Here, we investigate the relative importance of intrinsic (density-dependent) and extrinsic (climatic) factors impacting the dynamics of a tree frog (Hyla arborea) population over 22 years. A combination of log-linear density dependence and rainfall (with a 2-year time lag corresponding to development time) explain 75% of the variance in the rate of increase. Such fluctuations around a variable return point might be responsible for the seemingly erratic demography and disequilibrium dynamics of many amphibian populations.

Height distributions of Scots pine sapling stands affected by retained tree and edge stand competition

Abstract

Measurement of the tree root growth using electrical impedance spectroscopy

Abstract

Estimating water application efficiency for drip irrigation emitter patterns on banana

The objective of this work was to evaluate root and water distribution in irrigated banana (Musa sp.), in order to determine the water application efficiency for different drip irrigation emitter patterns. Three drip emitter patterns were studied: two 4-L h-1 emitters per plant (T1), four 4-L h-1 emitters per plant (T2), and five 4-L h-1 emitters per plant (T3). The emitters were placed in a lateral line. In the treatment T3, the emitters formed a continuous strip. The cultivated area used was planted with banana cultivar BRS Tropical, with a 3-m spacing between rows and a 2.5-m spacing between plants. Soil moisture and root length data were collected during the first production cycle at five radial distances and depths, in a 0.20x0.20 m vertical grid. The experiment was carried out in a sandy clay loam Xanthic Hapludox. Soil moisture data were collected every 10 min for a period of five days using TDR probes. Water application efficiency was of 83, 88 and 92% for the systems with two, four and five emitters per plant, respectively. It was verified that an increase in the number of emitters in the lateral line promoted better root distribution, higher water extraction, and less deep percolation losses.

Functions for estimating stem diameter and tree age using tree height, crown width and existing stand database information

Abstract

The geometric structure of the brain fiber pathways.

The structure of the brain as a product of morphogenesis is difficult to reconcile with the observed complexity of cerebral connectivity. We therefore analyzed relationships of adjacency and crossing between cerebral fiber pathways in four nonhuman primate species and in humans by using diffusion magnetic resonance imaging. The cerebral fiber pathways formed a rectilinear three-dimensional grid continuous with the three principal axes of development. Cortico-cortical pathways formed parallel sheets of interwoven paths in the longitudinal and medio-lateral axes, in which major pathways were local condensations. Cross-species homology was strong and showed emergence of complex gyral connectivity by continuous elaboration of this grid structure. This architecture naturally supports functional spatio-temporal coherence, developmental path-finding, and incremental rewiring with correlated adaptation of structure and function in cerebral plasticity and evolution.

Brittle to ductile transition in a fiber bundle with strong heterogeneity

We analyze the failure process of a two-component system with widely different fracture strength in the framework of a fiber bundle model with localized load sharing. A fraction 0≤α≤1 of the bundle is strong and it is represented by unbreakable fibers, while fibers of the weak component have randomly distributed failure strength. Computer simulations revealed that there exists a critical composition αc which separates two qualitatively different behaviors: Below the critical point, the failure of the bundle is brittle, characterized by an abrupt damage growth within the breakable part of the system. Above αc, however, the macroscopic response becomes ductile, providing stability during the entire breaking process. The transition occurs at an astonishingly low fraction of strong fibers which can have importance for applications. We show that in the ductile phase, the size distribution of breaking bursts has a power law functional form with an exponent μ=2 followed by an exponential cutoff. In the brittle phase, the power law also prevails but with a higher exponent μ=92. The transition between the two phases shows analogies to continuous phase transitions. Analyzing the microstructure of the damage, it was found that at the beginning of the fracture process cracks nucleate randomly, while later on growth and coalescence of cracks dominate, which give rise to power law distributed crack sizes.

Energy balance measurements over a banana orchard in the Semiarid region in the Northeast of Brazil

The objective of this work was to evaluate the reliability of eddy covariance measurements, analyzing the energy balance components, evapotranspiration and energy balance closure in dry and wet growing seasons, in a banana orchard. The experiment was carried out at a farm located within the irrigation district of Quixeré, in the Lower Jaguaribe basin, in Ceará state, Brazil. An eddy covariance system was used to measure the turbulent flux. An automatic weather station was installed in a grass field to obtain the reference evapotranspiration (ET0) from the combined FAO-Penman-Monteith method. Wind speed and vapor pressure deficit are the most important variables on the evaporative process in both growing seasons. In the dry season, the heat fluxes have a similar order of magnitude, and during the wet season the latent heat flux is the largest. The eddy covariance system had acceptable reliability in measuring heat flux, with actual evapotranspiration results comparing well with those obtained by using the water balance method. The energy balance closure had good results for the study area, with mean values of 0.93 and 0.86 for the dry and wet growing seasons respectively.