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Ring profiler: a new method for estimating tree-ring density for improved estimates of carbon storage

Methods for estimating present and future carbon storage in trees and forests rely on measurements or estimates of tree volume or volume growth multiplied by specific gravity. Wood density can vary by tree ring and height in a tree. If data on density by tree ring could be obtained and linked to tree size and stand characteristics, it would be possible to more...

https://www.fs.usda.gov/treesearch/search?keywords=%22estimation%22&%3Bamp%3Bf%5B0%5D=author_facet%3A%22Spies%2C%20Thomas%22&%3Bf%5B0%5D=author_facet%3A%22Scott%2C%20C%20Tim%22&f%5B0%5D=author_facet%3A%22Zhu%2C%20J.Y.%22&f%5B1%5D=author_facet%3A%22Shortle%2C%20Walter%22&f%5B2%5D=author_facet%3A%22Greene%2C%20John%22&f%5B3%5D=author_facet%3A%22Hatfield%2C%20Cherilyn%22&f%5B4%5D=author_facet%3A%22Absher%2C%20Jim%22&f%5B5%5D=author_facet%3A%22Duan%2C%20Kai%22&f%5B6%5D=author_facet%3A%22Pierce%2C%20Ken%22

Author(s):

David W. Vahey; C. Tim Scott; J.Y. Zhu; Kenneth E. Skog

Year:

2012

Keywords:

statistics, estimation, sampling, modeling, remote sensing, forest health, data integrity, environmental monitoring, cover estimation, international forest monitoring

Source:

In: Morin, Randall S.; Liknes, Greg C., comps. Moving from status to trends: Forest Inventory and Analysis (FIA) symposium 2012; 2012 December 4-6; Baltimore, MD. Gen. Tech. Rep. NRS-P-105. Newtown Square, PA: U.S. Department of Agriculture, Forest Service, Northern Research Station. [CD-ROM]: 386-390.

Small Sample Properties of Asymptotically Efficient Estimators of the Parameters of a Bivariate Gaussian–Weibull Distribution

Two important wood properties are stiffness (modulus of elasticity or MOE) and bending strength (modulus of rupture or MOR). In the past, MOE has often been modeled as a Gaussian and MOR as a lognormal or a two or three parameter Weibull. It is well known that MOE and MOR are positively correlated. To model the simultaneous behavior of MOE and MOR for the purposes of...

Author(s):

Steve P. Verrill; James W. Evans; David E. Kretschmann; Cherilyn A. Hatfield

Year:

2012

Keywords:

Reliability, modulus of rupture, modulus of elasticity, normal distribution, Weibull distribution, likelihood, methods, ASTM D 5457

Source:

USDA Forest Service, Forest Products Laboratory, Research Paper, FPL-RP-667, 2012: 48 p.

Asymptotically Efficient Estimation of a Bivariate Gaussian-Weibull Distribution and an Introduction to the Associated Pseudo-truncated Weibull

Author(s):

Steve P. Verrill; James W. Evans; David E. Kretschmann; Cherilyn A. Hatfield

Year:

2015

Keywords:

Bivariate Gaussian-Weibull, Gaussian copula, Likelihood methods, Modulus, of rupture, Modulus of elasticity, Normal distribution, One-step Newton estimator, Reliability, Weibull distribution

Source:

Communications in Statistics - Theory and Methods

Conceptual net energy output for biofuel production from lignocellulosic biomass through biorefining

There is a lack of comprehensive information in the retrievable literature on pilot scale process and energy data using promising process technologies and commercially scalable and available capital equipment for lignocellulosic biomass biorefining. This study conducted a comprehensive review of the energy efficiency of selected sugar platform biorefinery process...

Author(s):

J.Y. Zhu; X.S. Zhuang

Year:

2012

Keywords:

Cellulosic ethanol/biofuel, Lignocellulosic biomass, Biorefinery and bioenergy, Life cycle analysis (LCA), Agriculture operation, Pretreatment

Source:

Progress in Energy and Combustion Science, 38 (2012) 583-598

Forest values and the impact of the federal estate tax on family forests

Previous research has suggested that heirs to family forest land may sell timber and/or land in order to pay state and/or federal estate taxes, which could result in land use conversion or other adverse ecological impacts. We estimated the number of Minnesota family forest landowners and the associated acreage that could be subject to estate taxes at various exemption...

Author(s):

Brenton J. Dickinson; Brett J. Butler; Michael A. Kilgore; Paul Catanzaro; John Greene; Jaketon H. Hewes; David Kittredge; Mary Tyrrell

Year:

2012

Keywords:

statistics, estimation, sampling, modeling, remote sensing, forest health, data integrity, environmental monitoring, cover estimation, international forest monitoring

Source:

Quantification of live aboveground forest biomass dynamics with Landsat time-series and field inventory data: A comparison of empirical modeling approaches

Spatially and temporally explicit knowledge of biomass dynamics at broad scales is critical to understanding how forest disturbance and regrowth processes influence carbon dynamics. We modeled live, aboveground tree biomass using Forest Inventory and Analysis (FIA) field data and applied the models to 20+ year time-series of Landsat satellite imagery to...

Author(s):

Scott L. Powell; Warren B. Cohen; Sean P. Healey; Robert E. Kennedy; Gretchen G. Moisen; Kenneth B. Pierce; Janet L. Ohmann

Year:

2010

Keywords:

biomass, Landsat, FIA, disturbance, curve-fitting, random forests

Source:

Remote Sensing of Environment. 114(5): 1053-1068.

An improved water budget for the El Yunque National Forest, Puerto Rico, as determined by the Water Supply Stress Index Model

Quantifying the forest water budget is fundamental to making science-based forest management decisions. This study aimed at developing an improved water budget for the El Yunque National Forest (ENF) in Puerto Rico, one of the wettest forests in the United States. We modified an existing monthly scale water balance model, Water Supply Stress Index (WaSSI), to reflect...

Author(s):

Liangxia Zhang; Ge Sun; Erika Cohen; Steven McNulty; Peter Caldwell; Suzanne Krieger; Jason Christian; Decheng Zhou; Kai Duan; Keren J. Cepero-Pérez

Year:

2018

Keywords:

tropical rainforests, water budgets, evapotranspiration, water yield, WaSSI model

Source:

Forest Science

Concentrations of Ca and Mg in early stages of sapwood decay in red spruce, eastern hemlock, red maple, and paper birch

The decay of coarse woody debris is a key component in the formation of forest soil and in the biogeochemical cycles of Ca and Mg. We tracked changes in density and concentration of Ca and Mg in sapwood of red maple (Acer rubrum L.), red spruce (Picea rubens Sarg.), paper birch (Betula papyrifera Marsh.), and...

Author(s):

Kevin T. Smith; Walter C. Shortle; Jody Jellison; Jon Connolly; Jonathan Schilling

Year:

2007

Keywords:

Source:

Canadian Journal of Forest Research 37: 957-965.

Approaches to measuring cultural diversity in recreation

Measuring cultural diversity in recreation has become an important topic because of the increasing coverage of and interest in ethnicity and cross-cultural aspects of recreation. Introducing theories and methods from established disciplines other than leisure studies/recreation and park studies is necessary to understand this important issue. In this article, we first...

Author(s):

Chieh-Lu Li; James D. Absher; Yi-Chung Hsu; Alan R. Graefe

Year:

2008

Keywords:

Culture, diversity, outdoor recreation, measurement

Source:

In: Chavez, Deborah J.; Winter, Patricia L.; Absher, James D., eds. 2008. Recreation visitor research: studies of diversity. Gen. Tech. Rep. PSW-GTR-210. Albany, CA: U.S. Department of Agriculture, Forest Service, Pacific Southwest Research Station. 207-216. Chapter 17

Specific surface to evaluate the efficiencies of milling and pretreatment of wood for enzymatic saccharification

Sieving methods have been almost exclusively used for feedstock size-reduction characterization in the biomass refining literature. This study demonstrates a methodology to properly characterize specific surface of biomass substrates through two dimensional measurement of each fiber of the substrate using a wet imaging technique. The methodology provides more...

Author(s):

Junyong Zhu; G.S. Wang; X.J. Pan; Roland Gleisner

Year:

2009

Keywords:

Specific surface, bioprocessing, enzymatic saccharification, hydrolysis, feedstock processing, size reduction, disk and hammer milling, cellulosic ethanol, pretreatment, enzymes, biotechnology, enzymes, industrial applications, energy applications, energy consumption, glucose, biomass energy, sugars, biomass utilization, alcohol, size reduction of materials, cellulose, fibers, wood chips, fractionation, bioconversion, chemical utilization, biorefining, wood extractives, ethanol, cellulosic materials, sieving, wet imaging, thermomechanical processes, wood fibers, chips

Source:

Chemical engineering science. Vol. 64, no. 3 (2009).

High Titer Ethanol and Lignosulfonate Production from SPORL Pretreated Poplar at Pilot Scale

Poplar NE222 (Populus deltoides Bartr. ex Marsh P. nigra L.) wood chips were pretreated in a 390 L pilot-scale rotating wood-pulping digester using a dilute sulfite solution of approximately pH 1.8 at 160°C for 40 min for bioconversion to ethanol and lignosulfonate (LS). An estimated combined hydrolysis factor (CHF) of 3.3 was...

Author(s):

Haifeng Zhou; J. Y. Zhu; Roland Gleisner; Xueqing Qiu; Eric Horn

Year:

2015

Keywords:

forest biorefinery, biofuel, process scale-up, high solids fermentation, enzymatic saccharification/hydrolysis, lignosulfonate, poplar wood

Source:

Frontiers in Energy Research