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The pulp and paper industry in Indonesia is the tenth largest producer in the world, with Acacia and Eucalyptus as the main genera used for production; however, limited publications exist related to Eucalyptus growth models in Indonesia compared with other regions. Time-based models have been developed in which height, stand density, and basal area are predicted based on initial conditions and age. In contrast, a state-space approach utilizes the rate of change of these three state variables. Previous direct comparisons of these two approaches are generally limited. Consequently, the objective of this study was to compare two stand-level growth modeling approaches for Eucalyptus hybrid species on Sumatera (Sumatra) Island using both time-based and state-space methods. Our results indicate that dynamic models using either time-based or state-space approaches are adequate for predicting stand parameters to rotation age. A modified Bazukis matrix indicated that the behavior of both methods produced reliable predictions that were biologically reasonable in terms of stand development; however, the time-based approach provided better performance than the state-space approach on a variety of equivalence tests and goodness-of-fit statistics. Overall, the analysis highlights the advantages and disadvantages of these two commonly used, yet highly contrasting, stand-level growth modeling approaches, which need further consideration and evaluation. Key words: growth and yield, time-based model, state-space model, Eucalyptus hybrid clone, Indonesia. L'industrie des pates et papiers de l'Indonesie est le dixieme plus grand producteur au monde et utilise principalement les genres Acacia et Eucalyptus pour cette production; toutefois, il existe peu de publications traitant de modeles de croissance de l'eucalyptus en Indonesie comparativement a d'autres regions. Des modeles temporels ont ete mis au point dans lesquels la hauteur, la densite du peuplement et la surface terriere sont predites en fonction des conditions initiales et de l'age. En revanche, une approche par etats spatiaux utilise le taux de changement de ces trois variables d'etat. Les comparaisons directes de ces deux approches sont peu frequentes. Par consequent, l'objectif de cette etude etait de comparer deux approches de modelisation de la croissance a l'echelle du peuplement pour les especes d'eucalyptus hybrides de l'ile de Sumatera (Sumatra) en utilisant les methodes temporelles et d'etats spatiaux. Nos resultats indiquent que les modeles dynamiques utilisant des approches temporelles ou par etats spatiaux sont adequats pour predire les parametres des peuplements jusqu'a l'age d'exploitabilite. Une matrice modifiee de Bazukis indiquait que le comportement des deux methodes a produit des previsions fiables et biologiquement raisonnables en ce qui concerne le developpement des peuplements; cependant, l'approche temporelle etait superieure a l'approche par etats spatiaux dans le cas de plusieurs tests d'equivalence et de statistiques de validite d'ajustement. Dans l'ensemble, l'analyse met en evidence les avantages et les inconvenients de ces deux approches de modelisation de la croissance a l'echelle du peuplement qui sont couramment utilisees, tout en etant tres differentes, ce qui necessite un examen et une evaluation plus approfondis. [Traduit par la Redaction] Mots-cles : croissance et production, modele temporel, modele d'etats spatiaux, clone d'Eucalyptus hybride, Indonesie., Introduction The pulp and paper industry in Indonesia is the tenth largest producer in the world (Rini 2019). In 2018, Indonesia's paper production capacity was 16 million tonnes per year [...]

Using a two-phase sampling approach with systematic selection of large samples of covariates followed by a sampling with probability proportional to prediction (3P sampling) process to subsample field measures of the parameters of interest can be an efficient design to sample larger forest areas. To assist in obtaining predictions for each sample plot consistently and rapidly, we propose using a 360[degrees] spherical camera. In this study, three covariates derived from spherical images were evaluated: (i) basal area (P[BA]); (ii) sum of squared heights per hectare (P[SHT]); and (iii) stem fraction (P[SF]). These covariates were used to estimate volume. Sample simulations showed no biases in volume estimates for any of the three covariates. Overall, P[SF] had the lowest standard error percentages across different simulated sample sizes (10% for five subsamples to 2.5% for 50 subsamples), even though it had the lowest correlations with field volume (correlation = 0.30-0.31). This may be a result of the relatively consistent stand conditions within the study site. Based on our results, standard errors of 5% were obtainable with measurement fractions of about 25% of the number of image-based predictions when using P[SF] or P[BA] and 75% when using P[SHT]. Key words: 3P sampling, spherical image, stem fraction, photo point sampling, vertical point sampling. L'utilisation d'une approche d'echantillonnage en deux phases avec selection systematique de grands echantillons de covariables, suivie d'un processus d'echantillonnage avec probabilite proportionnelle a la prediction (echantillonnage 3P) pour sous-echantillonner les mesures sur le terrain des parametres d'interet, peut etre une conception efficace pour echantillonner de plus grandes regions forestieres. Nous proposons d'utiliser une camera spherique a 360[degrees], pour aider a obtenir des predictions pour chaque parcelle d'echantillonnage de maniere coherente et rapide. Dans cette etude, trois covariables derivees d'images spheriques ont ete evaluees : (i) la surface terriere (P[ST]); (ii) la somme de la hauteur des tiges au carre a l'hectare (P[SHT]); et (iii) la fraction des tiges (P[FT]). Ces covariables ont ete utilisees pour estimer le volume. Les simulations d'echantillonnage n'ont montre aucun biais dans l'estimation du volume pour aucune des trois covariables. Dans l'ensemble, P[FT] avait les pourcentages d'erreur-type les plus bas dans les differentes tailles d'echantillon simulees (10 % pour cinq sous-echantillons a 2,5 % pour 50 sous-echantillons), meme s'il avait les correlations les plus faibles avec le volume sur le terrain (correlation = 0,30-0,31). Cela peut etre le resultat des conditions de peuplement relativement uniformes dans le site d'etude. Sur la base de nos resultats, des erreurs-types de 5 % ont pu etre obtenues avec des intensites de mesure d'environ 25 % du nombre de predictions basees sur l'image lors de l'utilisation de P[FT] ou P[ST] et de 75 % lors de l'utilisation de P[SHT]. [Traduit par la Redaction] Mots-cles : echantillonnage 3P, image spherique, fraction des tiges, echantillonnage par points photographiques, echantillonnage par points verticaux., 1. Introduction In practice, forest inventory is designed to obtain estimates of forest conditions under time and cost constraints. Enhancing sampling efficiency is an important consideration in sample design (Freese [...]

Big basal area factor (big BAF) sampling is a widely used subsampling method to select measure-trees. Several studies have shown big BAF sampling to be an efficient sampling scheme. In this study, we use sector sampling (Smith et al. 2008, For. Sci. 54: 67-76) as an alternative subsample selection method. Based on some simulated mapped stands derived from three balsam fir (Abies balsamea (L.) Mill.) spacing trials in western Newfoundland, we show that sector subsampling is comparable to big BAF sampling in terms of estimated mean basal area ratios and their associated standard errors. Differences between big BAF sampling and sector sampling methods showed less than 1% difference across the three sites. As with big BAF sampling, changes in sample intensity had no significant (p < 0.05) effects on the accuracy of estimating mean biomass to basal area ratios and the resulting estimated mean biomasses per unit area. Key words: sector sampling, subsampling, basal area ratio estimation, sample efficiency, big BAF sampling, biomass estimation. L'echantillonnage par grand facteur de prisme (GFP) est une methode de sous-echantillonnage largement utilisee pour selectionner les arbres-etudes. Plusieurs etudes ont montre que l'echantillonnage par GFP est un plan d'echantillonnage efficace. Dans cette etude, nous utilisons l'echantillonnage sectoriel (Smith et al. 2008, For. Sci. 54: 67-76) comme methode alternative de selection des sous-echantillons. En se basant sur des peuplements cartographies simules issus de trois essais de degagement du sapin baumier (Abies balsamea (L.) Mill.) dans l'ouest de Terre-Neuve, nous montrons que le sous-echantillonnage sectoriel est comparable a un echantillonnage par GFP en termes d'estimation des ratios moyens de surface terriere et de leurs erreurs-types associees. Les comparaisons entre les methodes d'echantillonnage par GFP et par secteur montrent une difference de moins de 1 % entre les trois sites. Comme pour l'echantillonnage par GFP, les changements de densite de l'echantillon n'ont aucun effet significatif (p < 0,05) sur l'exactitude de l'estimation des ratios de la biomasse moyenne sur la surface terriere et sur les estimations de biomasses moyennes par unite de surface qui en resultent. [Traduit par la Redaction] Mots-cles : echantillonnage sectoriel, sous-echantillonnage, estimation du rapport de surface terriere, efficacite d'echantillonnage, echantillonnage par grand facteur de prisme, estimation de la biomasse., Introduction Many forest-level attributes such as volume, biomass, and carbon rely on individual tree measurements and allometric models (Kershaw et al. 2016). Direct measurement of these attributes is often impractical, [...]

We investigated whether the trophic ecology of an apex predator is influenced by ecosystem-level nutrient depletion. The feeding behavior and nutrient assimilation of a terrestrial salamander, Eastern Red-backed Salamander (Plethodon cinereus (Green, 1818)), was surveyed along a gradient of forest biogeochemistry. Recent studies have documented populations of these salamanders in forests with low-pH soils that were long thought to be fatal. One mechanism that may enable P. cinereus to tolerate acid-impaired habitats is its generalist life history. We sampled diet, invertebrate prey abundance, and tissue composition of P. cinereus from sites that range in calcium availability and soil pH in northern forests of North America. We found that P. cinereus consistently exhibited a generalist feeding strategy, having diverse diets closely representing resource availability. Prey abundances were unrelated to the biogeochemical gradient (excluding gastropods), indicating relatively intact food webs. Although P. cinereus at the two most acid-impaired sites consumed more prey, overall trophic strategies were consistent across the gradient. Salamander tissue composition was unrelated to variation in forest biogeochemistry, although manganese levels were elevated in the most acid-impaired forests. We suggest that a generalist feeding strategy, combined with diverse and compositionally stable food webs, facilitates tolerance by this abundant predator of the challenges imposed by acid-impaired habitats. Key words: calcium depletion, Eastern Red-backed Salamander, food web, Plethodon cinereus, salamander diet, trophic ecology. Nous avons verifie si l'ecologie trophique d'un predateur de niveau trophique superieur est influencee par l'appauvrissement en nutriments a l'echelle de l'ecosysteme. Le comportement d'alimentation et l'assimilation de nutriments d'une salamandre terrestre, la salamandre rayee (Plethodon cinereus (Green, 1818)), sont examines le long d'un gradient de biogeochimie de la foret. Des etudes recentes documentent des populations de ces salamandres dans des forets aux sols de faible pH longtemps soupconnes d'etre fatals. Un mecanisme qui pourrait permettre a P. cinereus de tolerer les habitats acidifies est son cycle biologique generaliste. Nous avons caracterise le regime alimentaire, l'abondance de proies invertebrees et la composition de tissus de P. cinereus de sites presentant differentes disponibilites du calcium et differents pH du sol dans des forets septentri-onales d'Amerique du Nord. Nous avons constate que P. cinereus presente uniformement une strategie d'alimentation generaliste, ses regimes alimentaires varies refletant etroitement les ressources disponibles. L'abondance de proies n'etait pas reliee au gradient biogeochimique (a l'exception des gasteropodes), ce qui indique des reseaux trophiques relativement intacts. Meme si les P. cinereus aux deux sites les plus acidifies consommaient plus de proies, il y avait une coherence dans les strategies trophiques globales le long du gradient. La composition des tissus des salamandres n'etait pas reliee aux variations biogeochimiques des forets, les concentrations de manganese etant toutefois elevees dans les forets les plus acidifiees. Nous suggerons qu'une strategie d'alimentation generaliste, combinee a des reseaux trophiques varies et de composition stable, favorise la tolerance de ce predateur abondant aux defis que posent les habitats acidifies. [Traduit par la Redaction] Mots-cles: appauvrissement du calcium, salamandre rayee, reseau trophique, Plethodon cinereus, regime alimentaire des salamandres, ecologie trophique., Introduction The eastern deciduous forest biome of North America has been shaped over the last century by many anthropogenic drivers of environmental change, but air pollution in its many forms [...]

Northern hardwood species display a variety of forms and defects that can reduce stem quality and complicate their timber management. However, for the most part, growth and yield models do not account for the influence of stem form and damage. This study determined the influence of stem form and damage on growth, survival, and projected future sawlog value among several northern commercial hardwood species. To accomplish this, hardwood trees on 112 permanent plots across three long-term research sites in Maine were assigned stem form and risk classes using a tree classification system developed in New Brunswick. A highly significant influence of stem form and risk on annualized individual-tree diameter increment and survival was found. Inclusion of these equations into a regional growth and yield model highlighted the importance of stem form and defects on long-term simulations as projected stand-level future value was significantly reduced by over 17%, on average (range of 13% to 28%), when compared with projections that did not include that tree-level information. The results highlight the importance of stem form and defects, as well as the need to account for them, in growth and yield applications that assess the forecasted value of commercially important hardwood stands. Key words: paper birch, quaking aspen, red maple, red oak, yellow birch. Le tronc des especes de feuillus nordiques presente une variete de formes et de defauts qui peuvent diminuer la qualite des arbres et compliquer l'amenagement de ces essences pour la production de bois d'oeuvre. Cependant, la plupart des modeles de croissance et de rendement tiennent encore tres peu compte de l'impact de la forme du tronc et des defauts. Cette etude avait pour but de determiner l'influence de la forme du tronc et des defauts sur la croissance, la survie et la valeur future estimee des billes de sciage de plusieurs especes commerciales de feuillus nordiques. A cette fin, nous avons utilise un systeme de classification des arbres elabore au Nouveau-Brunswick et attribue une forme du tronc et une classe de risque de perte de vigueur a chaque tige de feuillus nordiques presente dans 112 placettes permanentes reparties dans trois stations de recherche a long terme situees dans le Maine. La forme du tronc et le risque avaient une influence tres significative sur le taux de survie et l'accroissement en diametre annualise des tiges prises individuellement. L'inclusion de ces equations dans un modele regional de croissance et de rendement a mis en evidence l'importance de la forme du tronc et des defauts pour les simulations a long terme etant donne que la valeur future estimee a l'echelle du peuplement etait significativement reduite, de plus de 17 % en moyenne (etendue de 13 a 28 %), comparativement aux projections qui n'incluaient pas cette information au sujet de chaque tige. Les resultats font aussi ressortir l'importance de la forme du tronc et des defauts, ainsi que la necessite d'en tenir compte, dans les applications de croissance et de rendement qui evaluent la valeur anticipee des peuplements feuillus qui ont une importance commerciale. [Traduit par la Redaction] Mots-cles : bouleau blanc, peuplier faux-tremble, erable rouge, chene rouge, bouleau jaune., Introduction Northern hardwood and mixed-wood forest types account for approximately 8.1 million ha across the northeastern United States (US) and portions of Canada adjacent to this region (Leak et al. [...]

The conic-paraboloid volume equation is receiving increased use with downed coarse woody material (CWM), but the consequences for taper have not been identified mathematically. Requiring that subdivision of a conic-paraboloid yields two smaller conic-paraboloids leads to an exact taper equation intermediate between those of cones and second-order paraboloids. This exact taper equation does not have an explicit inverse, however. An alternative, naive approach does have an explicit inverse, but subdivision does not yield two conic-paraboloids. The exact conic-paraboloid is closely approximated by Fermat's paraboloid with exponent 7/5. The exact and naive conic-paraboloids match in volume; differences in taper are [less than or equal to] 2.2% of large-end cross-sectional area and [less than or equal to] 5.9% of large-end diameter, while differences in inverse taper are [less than or equal to] 3.7% of total length. Fermat's paraboloid is always within 1.2% of total volume; differences in taper are [less than or equal to] 0.8% of large-end cross-sectional area and [less than or equal to] 2.0% of large-end diameter, while differences in inverse taper are [less than or equal to] 1.1% of total length. Such differences are negligible given the variety of CWM shapes and practical measurement challenges. Either the exact conic-paraboloid or the corresponding Fermat's paraboloid provides appropriate equations for estimating the volume and taper of CWM that is intermediate between conical and ordinary paraboloid frusta. Key words: coarse woody debris, downed dead wood, carbon accounting, forest inventory. L'equation du volume d'un paraboloide conique est de plus en plus utilisee pour le materiel ligneux grossier (MLG) au sol mais les repercussions sur la conicite n'ont pas ete identifiees du point de vue mathematique. Exiger que la subdivision d'un paraboloide conique engendre deux paraboloides coniques plus petits mene a une equation exacte de la conicite, intermediaire entre celle des cones et celle des paraboloides du second ordre. Cependant, cette equation exacte de la conicite n'a pas d'inverse explicite. Une approche alternative, naive, n'a pas d'inverse explicite mais la subdivision n'engendre pas deux paraboloides coniques. Le paraboloide de Fermat, avec un exposant 7/5, produit une tres bonne approximation du paraboloide conique exact. Les paraboloides exact et naif ont un volume semblable; la differences de conicite est [less than or equal to] 2,2 % de la surface de la section au gros bout et [less than or equal to] 5,9 % du diametre au gros bout tandis que la difference de conicite inverse est [less than or equal to] 3,7 % de la longueur totale. Le paraboloide de Fermat est toujours en dedans de 1,2 % du volume total, la difference de conicite est [less than or equal to] 0,8 % de la surface de la section au gros bout et [less than or equal to] 2,0 % du diametre au gros bout, tandis que la difference de conicite inverse est [less than or equal to] 1,1 % de la longueur totale. De telles differences sont negligeables etant donne la variete des formes du MLG et les defis pratiques que represente leur mesure. Soit le paraboloide conique exact, ou le paraboloide correspondant de Fermat, fournissent des equations adequates pour estimer le volume et la conicite du MLG qui est intermediaire entre le tronc de cone du paraboloide conique et celui du paraboloide ordinaire. [Traduit par la Redaction] Mots-cles: debris ligneux grossiers, bois mort au sol, bilan du carbone, inventaire forestier., Introduction Downed coarse woody material (CWM) has become a focus of substantial research and management attention in the past three decades (Harmon et al. 1986; Russell et al. 2015). The [...]

The forest understory is often associated with rapid rates of carbon and nutrient cycling, but cost-efficient quantification of its biomass remains challenging. We tested a new field technique for understory biomass assessment using an off-the-shelf handheld laser rangefinder. We conducted laser sampling in a pine forest with an understory dominated by invasive woody shrubs, especially Rhamnus frangula L. Laser sampling was conducted using a rangefinder, mounted on a monopod to provide a consistent reference height, and pointed vertically downward. Subsequently, the understory biomass was measured with destructive sampling. A series of metrics derived from the airborne LiDAR literature were evaluated alone and in combination for prediction of understory biomass using best-subsets regression. Resulting fits were good ([r.sup.2] = 0.85 and 0.84 for the best single metric and best additive metric, respectively, and [R.sup.2] = 0.93 for the best multivariate model). The results indicate that laser sampling could substantially reduce the need for costly destructive sampling within a double-sampling context. Key words: light detection and ranging, vegetation structure, understory biomass, inventory, invasive species, point intercept sampling. Le sous-bois forestier est souvent associe au recyclage rapide du carbone et des nutriments, mais la quantification de sa biomasse de facon efficace et peu couteuse reste difficile. Nous avons teste une nouvelle technique pour revaluation sur le terrain de la biomasse du sous-bois a l'aide d'un telemetre laser portatif disponible sur le marche. Nous avons effectue un echantillonnage au laser dans une foret de pins avec un sous-bois domine par des arbustes ligneux envahissants, en particulier Rhamnus frangula L. L'echantillonnage au laser a ete effectue a l'aide d'un telemetre, monte sur un monopode pour fournir une hauteur de reference constante, et dirige verticalement vers le bas. Par la suite, la biomasse du sous-bois a ete mesuree avec un echantillonnage destructif. Une serie de parametres, derives de la litterature relative au LiDAR aeroporte, ont ete evalues seuls et combines pour predire la biomasse du sous-bois en utilisant la regression des meilleurs sous-ensembles. Les ajustements ainsi obtenus etaient bons ([r.sup.2] = 0,85 et 0,84 respectivement pour la meilleure metrique unique et la meilleure metrique additive et [R.sup.2] = 0,93 pour le meilleur modele multivarie). Les resultats indiquent que l'echantillonnage au laser pourrait reduire considerablement le besoin d'un echantillonnage destructif couteux dans le contexte d'un double echantillonnage. [Traduit par la Redaction] Mots-cles : detection et telemetrie par ondes lumineuses (LiDAR), structure de la vegetation, biomasse du sous-bois, inventaire, espece envahissante, echantillonnage ponctuel., Introduction The forest understory--including the herbaceous layer, as well as erect woody shrubs--typically contains a small fraction of the aboveground biomass of temperate and boreal forests, but it can play [...]

Northern hardwood trees display a wide variety of stem forms and defects, which can substantially reduce their financial value and also complicate their silviculture. While attributes of stem form and defect have been incorporated into tree classification systems, their ability to assess product value and recovery in standing trees has not been adequately tested. To address this issue, we classified stem form and risk using a system developed by the Northern Hardwoods Research Institute (NHRI) for four species across several locations in Maine, New Hampshire, and New Brunswick: sugar maple (Acer saccharum Marsh.), red maple (Acerrubrum L.), yellow birch (Betula alleghaniensis Britton), and northern red oak (Quercus rubra L.). Using these data, we (i) quantified interspecific and regional variation in stem form and damage, (ii) related potential sawlog recovery to tree size, form, and risk, and (iii) compared the efficacy of the NHRI system with a commonly used classification system and a continuous measure of stem quality. High variation in both stem form and damage among the species was found, with red maple showing the largest range. A simplified NHRI system including three form classes proved to be sufficient in differentiating sawlog potential in individual trees, while a model using a continuous measure of stem quality (estimated merchantable sawlog height) performed best. Key words: stem form, risk, northern hardwoods, classification systems, sawlog potential. Le tronc des feuillus nordiques presente une variete de formes et de defauts qui peuvent reduire substantiellement leur valeur financiere et aussi compliquer leur sylviculture. Bien que les attributs de la forme et des defauts du tronc aient ete incorpores dans des systemes de classement des arbres, leur capacite a estimer le rendement et la valeur des produits chez les arbres sur pied n'a pas ete adequatement testee. Pour aborder ce probleme, nous avons classe la forme du tronc et le risque de perte de vigueur a plusieurs endroits dans le Maine, le New Hampshire et le Nouveau-Brunswick en utilisant un systeme developpe par l'Institut de recherche sur les feuillus nordiques (IRFN) pour quatre especes : l'erable a sucre (Acer saccharum Marsh.), l'erable rouge (Acer rubrum L.), le bouleau jaune (Betula alleghaniensis Britton) et le chene rouge (Quercus rubra L.). A l'aide de ces donnees nous avons (i) quantifie la variation interspecifique et regionale de la forme de la tige et des dommages, (ii) relie le rendement potentiel en billes de sciage a la taille de l'arbre, la forme du tronc et le risque de perte de vigueur et (iii) compare l'efficacite du systeme de l'IRFN a celle d'un systeme de classement generalement utilise ainsi qu'a la mesure continue de la qualite du tronc. Nous avons trouve une grande variation de la forme du tronc et des dommages parmi les especes; l'ampleur de la variation etait la plus importante chez l'erable rouge. Le systeme de l'IRFN simplifie comportant trois classes de de forme s'est avere suffisant pour differencier les billes de sciage potentielles chez les arbres individuels tandis qu'un modele utilisant la mesure continue de la qualite du tronc (hauteur marchande estimee en billes de sciage) etait le plus performant. [Traduit par la Redaction] Mots-cles: forme du tronc, risque de perte de vigueur, feuillus nordiques, systeme de classement, bille de sciage potentielle., Introduction The northern hardwood forest type covers approximately 8.1 million ha in the United States (US), spanning from New York into portions of Canada adjacent to this region (Leak et [...]

This study presents an approach for predicting stand-level forest attributes utilizing mobile laser scanning data collected as a nonprobability sample. Firstly, recordings of stem density were made at point locations every 10th metre along a subjectively chosen mobile laser scanning track in a forest stand. Secondly, kriging was applied to predict stem density values for the centre point of all grid cells in a 5 m x 5 m lattice across the stand. Thirdly, due to nondetectability issues, a correction term was computed based on distance sampling theory. Lastly, the mean stem density at stand level was predicted as the mean of the point-level predictions multiplied with the correction factor, and the corresponding variance was estimated. Many factors contribute to the uncertainty of the stand-level prediction; in the variance estimator, we accounted for the uncertainties due to kriging prediction and due to estimating a detectability model from the laser scanning data. The results from our new approach were found to correspond fairly well to estimates obtained using field measurements from an independent set of 54 circular sample plots. The predicted number of stems in the stand based on the proposed methodology was 1366 with a 12.9% relative standard error. The corresponding estimate based on the field plots was 1677 with a 7.5% relative standard error. Key words: covariogram, detectability function, forest management, model-based inference. Cette etude presente une approche pour predire les attributs forestiers a l'echelle du peuplement en utilisant des donnees de balayage laser mobile recueillies comme un echantillon non probabiliste. Tout d'abord, la densite des tiges a ete notee de facon ponctuelle a tous les decimetres le long d'un transect de balayage laser mobile choisi de maniere subjective dans un peuplement forestier. Deuxiemement, une technique de krigeage a ete appliquee pour predire la valeur de la densite des tiges pour le point central de toutes les cellules d'une grille avec une maille de 5 m x 5 m dans le peuplement. Troisiemement, en raison de problemes de non detection, un terme de correction a ete calcule sur la base de la theorie de l'echantillonnage selon la distance. Enfin, la densite moyenne des tiges a l'echelle du peuplement a ete predite comme etant la moyenne des predictions de chaque point multipliee par le facteur de correction, puis la variance correspondante a ete estimee. De nombreux facteurs contribuent a l'incertitude de la prediction a l'echelle du peuplement; dans l'estimateur de variance, nous avons tenu compte des incertitudes liees a la prediction de krigeage et a l'estimation d'un modele de detectabilite a partir des donnees de balayage laser. Les resultats de notre nouvelle approche correspondent assez bien aux estimations obtenues en utilisant des mesures de terrain a partir d'un ensemble independant de 54 parcelles echantillons circulaires. Sur la base de la methodologie proposee, le nombre de tiges predit dans le peuplement etait de 1366 avec une erreur standard relative de 12,9 %. L'estimation correspondante sur la base des parcelles de terrain etait de 1677 avec une erreur standard relative de 7,5 %. [Traduit par la Redaction] Mots-cles: covariogramme, fonction de detectabilite, gestion des forets, inference fondee sur un modele., Introduction Traditionally, stand-level forest inventories have been based on field surveys where the surveyor allocates sample plots either subjectively or by random sampling to assess key stand characteristics such as [...]

High-elevation forests that contain mature, closed canopy stands are considered important habitat for American martens (Martes americana (Turton, 1806)) in the northeastern United States. To investigate this hypothesis, we monitored 15 radio-collared martens over a 2-year period and measured spatial use, as well as second- and third-order resource selection, from 33 seasonal home ranges and 889 telemetry locations. The population was composed primarily of adults that had small home-range size with average seasonal fidelity. During leaf-off seasons, martens selected against regenerating forest at both scales and selected for mixedwood and softwood forests and areas with rugged terrain within home ranges. Second-order selection was less pronounced during leaf-on seasons, yet martens exhibited greater selection for hardwood forest and areas with rugged terrain within home ranges. Home-range size was correlated positively with the amount of regenerating forest and body-condition index scores were lower during winter, indicating that these spatial and temporal attributes were influential. Although martens utilized low-elevation forest with extensive timber harvesting, contiguous, mature, and rugged high-elevation forest was used preferentially during winter. Land managers should minimize disturbance of montane ecosystems to ensure population viability for martens and other boreal forest species along distributional edges. Key words: resource selection, terrain ruggedness, habitat specialist, matrix habitat, body-condition index, American marten, Martes americana. Les forets de haute altitude qui renferment des peuplements a couvert ferme matures sont considerees comme etant des habitats importants pour les martes d'Amerique (Martes americana (Turton, 1806)) dans le nord-est des Etats-Unis. Pour explorer cette hypothese, nous avons surveille 15 martes munies de colliers emetteurs sur une periode de 2 ans et mesure l'utilisation de l'espace et la selection des ressources de deuxieme et troisieme ordres a partir de 33 domaines vitaux saisonniers et 889 lieux de telemetrie. La population etait principalement composee d'adultes dont la taille du domaine vital etait petite et la fidelite saisonniere, moyenne. Durant les saisons sans feuilles, les martes evitaient les forets en regeneration aux deux echelles et choisissaient des forets mixtes et de coniferes et des zones presentant un relief accidente a l'interieur des domaines vitaux. Si la selection de deuxieme ordre etait moins prononcee durant la saison des feuilles, les martes presentaient toutefois une preference pour les forets de feuillus et les zones presentant un relief accidente a l'interieur des domaines vitaux. La taille du domaine vital etait positivement correlee a la quantite de forets en regeneration, et les notes d'embonpoint etaient plus faibles durant l'hiver, ce qui indique une influence de ces attributs spatiaux et temporels. Si les martes utilisaient des forets de plus faible altitude caracterisees par une recolte du bois extensive, les forets contigues matures et accidentees de haute altitude etaient utilisees preferentiellement durant l'hiver. Les amenageurs devraient minimiser la perturbation des ecosystemes montagnards pour assurer la viabilite des populations de martes et d'autres especes des forets boreales le long des limites de leurs aires de repartition. [Traduit par la Redaction] Mots-cles : selection des ressources, relief du terrain, specialiste en matiere d'habitat, habitat de matrice, indice d'embonpoint, marte d'Amerique, Martes americana., Introduction Land-use practices and climate change are considered significant threats to wildlife populations (Mantyka-Pringle et al. 2012), especially for species along distributional edges (e.g., Carroll 2007). Consequently, there is a [...]

The most efficient way to obtain stand inventory data with terrestrial laser systems (TLS) is with the single-scan mode, which involves taking one scan at a single point. With a single-scan setup, there will be a nondetection of trees in a plot and the representation of the individual trees will be incomplete. We explore how stand-level volume estimates, based on the single-scan mode, perform compared with standard inventory estimates. We base our study on 166 plots in 12 mature stands dominated by Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies L. Karst) in southern Norway. First, we compare individual-tree volume estimates from TLS with estimates from volume functions and measurements from harvesters. We show that individual-tree volumes can be estimated with high precision and accuracy with TLS in single-scan mode. Secondly, we test three approaches for correction of nondetection relying on model-based estimates of the detection probability obtained by point transect sampling estimators. We show that all three approaches adjust for nondetection and yield stand-level volume estimates that are similar to those obtained by fixed-area sampling. In conclusion, our results indicate that stand-level volume estimates, based on single-scan mode TLS data, perform well compared with standard inventory estimates. Key words: Lidar, TLS, forest inventory, volume, distance sampling, nondetection, angle count sampling. Le mode de balayage unique avec le lidar terrestre, c'est-a-dire un seul balayage en un seul point, represente la facon la plus efficace d'obtenir les donnees d'inventaire des peuplements. Avec le mode de balayage unique, certains arbres ne seront pas detectes dans une placette et la representation des arbres individuels sera incomplete. Nous explorons comment les estimations de volume a l'echelle du peuplement fondees sur le mode de balayage unique performent par rapport aux estimations de l'inventaire standard. Nous basons notre etude sur 166 placettes dans 12 peuplements matures, domines par le pin sylvestre (Pinus sylvestris L.) et l'epicea commun (Picea abies (L.) Karst.), situes dans le sud de la Norvege. Tout d'abord, nous comparons les estimations du volume d'arbres individuels realisees avec le lidar terrestre aux estimations obtenues avec des fonctions de volume et des mesures provenant des abatteuses-tronconneuses. Nous montrons que le volume d'arbres individuals peut etre estime avec une grande precision et exactitude avec le lidar terrestre en mode de balayage unique. Deuxiemement, nous testons trois approches pour corriger la non detection en s'appuyant sur des estimations basees sur des modeles de probabilite de detection obtenue grace aux estimateurs d'echantillonnage par viree de placettes circulaires a rayon variable. Nous montrons que les trois approches reglent le probleme de la non detection et produisent des estimations du volume a l'echelle du peuplement similaires a celles obtenues par l'echantillonnage par placettes a rayon fixe. En conclusion, nos resultats indiquent que les estimations du volume a l'echelle du peuplement basees sur les donnees du lidar terrestre en mode de balayage unique, performent aussi bien que celles de l'inventaire standard. [Traduit par la Redaction] Mots-cles: lidar, lidar terrestre, inventaire forestier, volume, echantillonnage selon la distance, non detection, echantillonnage par balayage sous angle constant., Introduction Recently, terrestrial laser systems (TLS) have emerged as promising tools for assessing forest inventory parameters such as individual-tree stem volume, taper, stem quality (Thies et al. 2004; Maas et [...]

Several recent studies have shown that the mass-based concentration of nitrogen in foliage (%N) is positively correlated with canopy near-infrared reflectance (NIRr) and midsummer shortwave albedo across North American forests. Understanding the mechanisms behind this relationship would aid in interpretation of remote sensing imagery and improve our ability to predict changes in reflectance under future environmental conditions. The purpose of this study was to investigate the extent to which foliar nitrogen at leaf and canopy scales covary with leaf- and canopy-scale structural traits that are known to influence NIR scattering and reflectance. To accomplish this, we compared leaf and canopy traits with reflectance spectra at 17 mixed temperate forest stands. We found significant positive associations among %N and NIRr at both the leaf and canopy scale. At the canopy scale, both %N and NIRr were correlated with a number of structural traits as well as with the proportional abundance of deciduous and evergreen foliage. Identifying specific causal factors for observed reflectance patterns was complicated by interrelations among multiple traits across scales. Among simple metrics of canopy structure, we saw no relationship between NIRr and leaf area index, but we observed a strong, inverse relationship with the number of leaves per unit canopy volume. Resume: Plusieurs etudes recentes ont montre que la concentration d'azote dans le feuillage (%N) basee sur la masse est positivement correlee avec le coefficient de reflexion du couvert forestier dans le proche infrarouge (PIR) et l'albedo dans les courtes longueurs d'onde au milieu de l'ete dans les forets d'Amerique du Nord. La comprehension du mecanisme qui soustend cette relation faciliterait l'interpretation des images obtenues par teledetection et ameliorerait notre capacite a predire l'impact des conditions environnementale futures sur le coefficient de reflexion. Cette etude avait pour but de determiner dans quelle mesure l'azote foliaire aux echelles des feuilles et du couvert forestier covarie avec les caracteristiques structurales aux echelles des feuilles et du couvert forestier reconnues pour influencer la dispersion et le coefficient de reflexion dans le PIR. Dans ce but, nous avons compare les caracteristiques des feuilles et du couvert forestier a l'aide du spectre du coefficient de reflexion de 17 peuplements mixtes de foret temperee. Nous avons trouve des relations positives significatives parmi le %N et le coefficient de reflexion dans le PIR aux echelles des feuilles et du couvert forestier. A l'echelle du couvert forestier, le %N et le coefficient de reflexion dans le PIR etaient correles avec plusieurs traits structuraux ainsi qu'avec l'abondance proportionnelle de feuilles caduques et persistantes. L'identification des facteurs specifiques, qui determinent les valeurs du coefficient de reflexion que nous avons observees, etait compliquee par des interactions entre plusieurs caracteristiques aux differentes echelles. Parmi les metriques simples de structure du couvert forestier, nous n'avons pas observe de relation entre le coefficient de reflexion dans le PIR et l'indice de surface foliaire mais nous avons observe une relation inverse etroite avec le nombre de feuilles par unite de volume du couvert forestier. [Traduit par la Redaction], Introduction Nitrogen concentrations in foliage (%N) have long been known to influence leaf-level photosynthetic capacity and stand-level C uptake (Field and Mooney 1986; Reich et al. 1997; Reich 2012), and [...]

To ensure survival in the host, bacteria have evolved strategies to acquire the essential element iron. In Neisseria gonorrhoeae, the ferric uptake regulator Fur regulates metabolism through transcriptional control of iron-responsive genes by binding conserved Fur box (FB) sequences in promoters during iron-replete growth. Our previous studies showed that Fur also controls the transcription of secondary regulators that may, in turn, control pathways important to pathogenesis, indicating an indirect role for Fur in controlling these downstream genes. To better define the iron-regulated cascade of transcriptional control, we combined three global strategies--temporal transcriptome analysis, genomewide in silica FB prediction, and Fur titration assays (FURTA)--to detect genomic regions able to bind Fur in vivo. The majority of the 300 iron-repressed genes were predicted to be of unknown function, followed by genes involved in iron metabolism, cell communication, and intermediary metabolism. The 107 iron-induced genes encoded hypothetical proteins or energy metabolism functions. We found 28 predicted FBs in FURTA-positive clones in the promoters and within the open reading frames of iron-repressed genes. We found lower levels of conservation at critical thymidine residues involved in Fur binding in the FB sequence logos of FURTA-positive clones with intragenic FBs than in the sequence logos generated from FURTA-positive promoter regions. In electrophoretic mobility shift assay studies, intragenic FBs bound Fur with a lower affinity than intergenic FBs. Our findings further indicate that transcription under iron stress is indirectly controlled by Fur through 12 potential secondary regulators. doi: 10.1128/JB.00741-09

Abstract: Perpendicular distance sampling (PDS) is a fast probability-proportional-to-size method for inventory of downed wood. However, previous development of PDS had limited the method to estimating only one variable (such [...]

Obtaining informed consent from a client to participate in psychotherapy includes providing an understanding of what treatment or evaluation is going to take place with the psychologist, as well as what the psychologist may or may not do with the client's records. Psychologists have an obligation to communicate clearly with their clients regarding informed consent. In this investigation, 1 Health Insurance Portability and Accountability Act Notice of Privacy Practices was solicited from a practicing psychologist in each state plus the District of Columbia. The authors then analyzed these forms using 2 measures of readability. A large majority (82%) of these forms were written at the ceiling reading level (12th grade), and almost the entire sample (94%) fell into the difficult range of reading ease. On the basis of the data obtained in this investigation, it is recommended that psychologists move to improve the readability of these documents and should do so to improve clinical practice, reduce liability, and follow ethical standards. Keywords: HIPAA, readability, informed consent

Abstract: The effort required for an extensive litterfall measurement campaign can be prohibitive. We propose a double sampling approach, in which a large set of traps is used in each [...]

The isolates of Listeria monocytogenes, an intracellular pathogen of food-borne disease, were subjected to multilocus genotyping assay (MLGT) to achieve a rapid identification of the subtypes in order to develop effective control measures for this pathogen. The method proved to be a powerful tool to identify the pathogens and for other epidemiological investigations.

To ensure survival, most bacteria must acquire iron, a resource that is sequestered by mammalian hosts. Pathogenic bacteria have therefore evolved intricate systems to sense iron limitation and regulate gene expression appropriately. We used a pan-Neisseria microarray to examine genes regulated in Neisseria gonorrhoeae in response to iron availability in defined medium. Overall, 203 genes varied in expression, 109 up-regulated and 94 down-regulated by iron deprivation. In iron-replete medium, genes essential to rapid bacterial growth were preferentially expressed, while iron transport functions, and predominantly genes of unknown function, were expressed in low-iron medium. Of those TonB-dependent proteins encoded in the FA1090 genome with unknown ligand specificity, expression of three was not controlled by iron availability, suggesting that these receptors may not be high-affinity transporters for iron-containing ligands. Approximately 30% of the operons regulated by iron appeared to be directly under control of Fur. Our data suggest a regulatory cascade where Fur indirectly controls gene expression by affecting the transcription of three secondary regulators. Our data also suggest that a second MerR-like regulator may be directly responding to iron availability and controlling transcription independent of the Fur protein. Comparison of our data with those recently published for Neisseria meningitidis revealed that only a small portion of genes were found to be similarly regulated in these closely related pathogens, while a large number of genes derepressed during iron starvation were unique to each organism.

The effects of aromatic compounds (toluene, benzene, p-xylene, anisole, aniline, and pyridine), temperature, and surface grafting method (surface- or solution-polymerized) on alkyl chain rotational and conformational order in a series of high-density octadecylsilane stationary phases ranging in surface coverage from 3.09 to 6.45 [micro]mol/[m.sup.2] are examined by Raman spectroscopy. Rotational and conformational order are assessed using the intensity ratio of the antisymmetric to symmetric v(C[H.sub.2]) modes as well as the frequency at which the symmetric v(C[H.sub.2]) band is observed. Alkyl rotational and conformational order decrease with decreasing surface coverage in these aromatic compounds, which is consistent with the behavior of these materials in air and in other solvents. In addition, order of the alkyl chains is dependent on solvent hydrophobicity, hydrogen-bonding ability, and basicity. The most hydrophobic compounds impart disorder to the stationary phase; the hydrogen-bonding aromatics increase the rotational order of homogeneously distributed, high-surface-coverage materials; and basic aromatic compounds increase the conformational order of high- and low-coverage materials as the basic compounds undergo silanophilic interactions with exposed surface silanols. From these observations, molecular pictures of the chromatographic interface that display interactions between the alkyl chains and these aromatic compounds are proposed.

Raman spectroscopy is used to examine the subtle effects of polar, hydrogen-bonding solvents; temperature; and the surface grafting method (surface- or solution-polymerized) on alkyl chain rotational and conformational order in a series of high-density octadecylsilane stationary phases ranging in surface coverage from 3.09 to 6.45 [micro]mol/[m.sup.2]. Rotational and conformational order is assessed using the intensity ratio of the antisymmetric to symmetric v(C[H.sub.2]) modes as well as the frequencies at which these Raman bands are observed. Alkyl rotational and conformational order decreases with decreasing surface coverage in these polar solvents, consistent with the behavior of these materials in air. For homogeneously distributed, high surface coverage materials, these polar solvents induce rotational ordering that is proposed to be due to the self-association of these solvents through hydrogen bonding or other dipole interactions at the alkylsilane-solvent interface. From these observations, molecular pictures of these solvent-stationary-phase interfaces are proposed in which solvent interaction with the stationary phase occurs primarily at the distal methyl group of the alkyl chains.

Raman spectroscopy is used to examine the effects of solvent, temperature, and surface grafting method (surface or solution polymerized) on alkyl chain rotational and conformational order in a series of high-density octadecylsilane stationary phases ranging in surface coverage from 3.09 to 6.45 [micro]mol/[m.sup.2]. Rotational and conformational order is assessed using the intensity ratio of the antisymmetric to symmetric v(C[H.sub.2]) modes as well as the frequency at which these Raman bands are observed. Solvents studied include perdeuterated hexane, toluene, chloroform, tetrahydrofuran, benzene, methanol, acetone, acetonitrile, and water. Stationary-phase order was investigated at temperatures between 258 and 323 K. Alkyl chain rotational and conformational order, and hence, solvation of the stationary phase, is dependent on solvent parameters (polarity, size, etc.), temperature, and stationary-phase properties (polymerization method and surface coverage). Information on stationary-phase conformational order allows solvent--stationary-phase interactions to be described in terms of a combination of adsorption and partitioning models for reversed-phase liquid chromatography. Finally, a distinct interplay between solvent- and temperature-induced ordering of these stationary phases is documented that is also a function of solvent and stationary-phase properties.

Raman spectroscopy is used to examine the effects of temperature, surface coverage, nature of the alkylsilane precursor (octadecyltrichlorosilane, methyloctadecyldichlorosilane, or dimethyloctadecylchlorosilane), and surface grafting method (surface or solution polymerized) on alkyl chain conformational order in a series of high-density octadecylsilane stationary phases ranging in surface coverage from 3.09 to 6.45 [micro]mol/[m.sup.2]. Conformational order is assessed using the intensity ratio of the antisymmetric and symmetric v(C[H.sub.2]) modes as well as the frequency at which these Raman bands are observed. Conformational order increases with surface coverage. Temperature-induced surface phase changes are observed between 258 and 343 K for this homologous series of stationary phases that are demonstrated to adhere to the Clapeyron equation for a simple first-order transition. Phase changes are discussed in terms of variation of the molar enthalpy, molar entropy, and molar volume of the stationary phase, all of which depend on surface coverage. For the limited range of systems investigated, a correlation between stationary-phase preparation (surface versus solution polymerized and nature of the silane precursor) and extent of alkyl chain order is not clearly observed. Instead, alkyl chain order is largely dependent on bonding density. A molecular picture of temperature-induced disorder in octadecylsilane stationary phases is proposed, with disorder originating at the distal carbon and propagating toward the proximal carbon.

Jack Kavanaugh and Norman Macht. Uncle Robbie. Cleveland OH: Society for American Baseball Research (SABR), 1999. 200 pp. Paper, $12.95. Just as they waited years and years for a World [...]

The fate of indigenous communities under the new republican order and how Indians manipulated it in order to survive, are explored. How identification affects villagers by first describing what the change to a new liberal order meant for local town governments, are discussed.

Ambystoma maculatum and Plethodon cinereus are sympatric across much of eastern North America. The field distributions of individuals of each species are thought to be determined primarily by environmental factors and intraspecific interactions. We investigated the hypothesis that members of A. maculatum would show aggressive behavior toward individual P. cinereus which may affect the distribution of members of this species in nature. We also investigated whether this aggressive behavior is better characterized as interference competition or attempted predation. During staged encounters in laboratory chambers, both male and female resident A. maculatum responded aggressively toward introduced P. cinereus. Direct observations and analysis of videotaped encounters showed that A. maculatum used behavior patterns more similar to those used during predation attempts than to those used in intraspecific interference competition. This aggressive biting by A. maculatum resulted in the consumption of over 9% of the P. cinereus intruders, although most (62%) of the P. cinereus escaped following these strikes. This aggression, although not yet clearly classifiable as either predation or interspecific interference, caused death and injury to P. cinereus and suggested that the presence of A. maculatum may affect the distribution of P. cinereus on the forest floor.

Radio broadcasting is likely to survive the technological advances of the 1990s. Improvements to AM broadcasting and the introduction of an AM stereo standard in 1993 should help AM radio. Digital audio broadcasting and satelite systems, and digital cable radio will compete with traditional radio broadcasting but may not undermine local radio services and could offer more choice in rural areas.. Radio broadcast data services is another competing growth area.

The extent to which younger and older adolescents differed in their value judgments of historically important events was examined. Subjects were asked to list the ten most important events that happened in or to th U.S. since 1900. The subjects' choices were analyzed as a function of sex, age, political and religious orientation, and family size. In addition, 100 undergraduates were asked to serve as judges and predict which categories would be cited more frequently by males and which females. Results indicated that the judges' predictions did not match the data. Age was a much better predictor of value judgements than sex. Further, several additional differences in value judgments were revealed that would have been missed had only the variables of sex and age been included in the analyses.

America's War for the Greater Middle East: A Military History, by Andrew J. Bacevich. New York: Random House, 2016. 453 pages. $30. The most recent book by Andrew Bacevich--a retired [...]