Showing papers in "Agricultural and Forest Meteorology in 2008"

TL;DR: In this paper, a set of vegetation indices belonging to three classes (normalized difference vegetation index (NDVI), modified simple ratio (MSR) index and the modified chlorophyll absorption ratio index (MCARI, TCARI) were tested using the PROSPECT and SAIL models.

TL;DR: In this article, the authors present results of the first comprehensive, multi-site comparison of these partitioning methods, and investigate the effects of partitioning method choice, data gaps, and intersite variability on estimated gross primary production and ecosystem respiration.

TL;DR: In this paper, the authors investigated potential causes for this bias using 4 years of coupled sap flux and latent heat flux (LE) measurements from a mature oak-hickory forest in North Carolina, USA.

TL;DR: In this paper, the authors measured annual C storage, or net ecosystem production (NEP), from 1999 to 2003 in an aspen-dominated, mixed-deciduous forest in Michigan, USA.

TL;DR: In this article, the authors developed a probabilistic technique to deal with the uncertainties and to simulate the impact of global warming on rice production and water use in China, against a global mean temperature (GMT) increase scale relative to 1961-1990 values.

TL;DR: In this paper, the authors used remotely sensed data from the Moderate Resolution Imaging Spectrometer (MODIS) instrument on board the National Aeronautics and Space Administration's (NASA) Terra satellite to scale up AmeriFlux NEE measurements to the continental scale.

TL;DR: In this article, CAN-EYE is used to estimate effective and true leaf area index (LAI) from unidirectional gap fractions measured in crops, whereas the true LAI is estimated introducing a clumping index in the Poisson law.

TL;DR: In this article, the applicability of the Bowen ratio-energy balance (BREB) method in the arid desert region of northwest China, simulated the variation of vineyard ET by Penman-Monteith (P-M), Shuttle-Wallace (S-W) and Clumping (C) models in this region and compared the estimated ET by the three models with the measured ET by BREB.

TL;DR: In this paper, the authors presented a method to estimate fuel moisture content (FMC) of Mediterranean vegetation species from satellite images in the context of fire risk assessment using two methodologies: empirical relations and statistical models based on simulated reflectances derived from radiative transfer models (RTM).

TL;DR: In this article, a perturbed-parameter crop modelling method together with a regional climate model (PRECIS) driven by the 2071-2100 SRES A2 emissions scenario was used to examine processes and uncertainties in yield simulation.

TL;DR: In this paper, the effective plant area index (PAIeff) retrievals by three major optical instruments, LAI-2000, AccuPAR, and Digital Hemispherical Photographs (DHPs), were analyzed over 10 crops (soybean, corn, alfalfa, sorghum, peanut and pasture) at the Manfredi site in Cordoba province, Argentina.

TL;DR: In this article, the authors collected most relevant and up-to-date European literature on the response of dry biomass production to planting density and nitrogen (N) fertilizer and provided quantitative estimates of the effect of these practices.

TL;DR: Results indicate that there exist organized progression of rainfall onset within the western Kenya region with the long rains showing a southerly progression while the short rains show a south-westerly progression.

TL;DR: Results show that respiration of the mycorrhizal component cannot be predicted by common temperature driven models in some ecosystems, and indicate a strong influence of forest canopy processes on the activity of roots and associated organisms.

TL;DR: In this paper, the mean characteristics of the advective CO2 fluxes in a first site-to-site comparison and evaluates the main problems for future research are presented.

TL;DR: In this paper, water vapor, energy fluxes, and environmental conditions were measured in an eastern Siberian larch forest for 7 water years, from 1998 to 2006, to understand the water-balance characteristics and interannual variation (IAV).

TL;DR: In this article, the authors investigated the influence of environmental factors on net ecosystem production (NEP), gross primary production (GPP), and ecosystem respiration (RE) in forest ecosystems across East Asia.

TL;DR: In this article, the authors evaluate several existing models estimating solar radiation based on daily minimum and maximum air temperature and/or precipitation for seven sites in the world, and investigate the impact of the estimated solar radiation on grass reference evapotranspiration (ETo) and total plant dry biomass simulations for maize.

TL;DR: Gash et al. as discussed by the authors measured gross rainfall, net rainfall, and stemflow in a mixed deciduous woodland in southern England over a period of 14 months and derived the evaporation rates from the wet canopy with the Penman-Monteith equation using the measured aerodynamic conductance to the momentum flux and, additionally, with the eddy covariance energy balance approach.

TL;DR: In this paper, the authors compare the statistical properties of the inferred random flux measurement error calculated first using residuals from five different models, and secondly using paired observations made under similar environmental conditions.

TL;DR: Wang et al. as discussed by the authors analyzed wheat WUE not only on grain yield basis, but also on photosynthesis basis and biomass basis, and then discussed the effects of irrigation regimes on wheat water use efficiency.

TL;DR: In this article, tree-to-tree and radial variations in xylem sap flux density (F d ), in addition to tree biometrics, were measured over a 2-year period (2005-2006) in two slope stand positions.

TL;DR: In this paper, the authors present results from 4 years (May 2001-May 2005) of water and energy flux measurements made in a no-till, irrigated maize-soybean rotation system in eastern Nebraska, USA.

TL;DR: In this article, the authors measured soil CO 2 efflux rate at 11 sites with different vegetation types, elevations and soil textures in a mountain area near Taiyuan city, China, over a period of 1 year.

TL;DR: In this paper, the CROPGRO-Soybean model was calibrated and validated for the diverse soybean-growing environments of central and peninsular India, and the validated model was used to estimate potential yields (water non-limiting and water limiting) and yield gaps of soybean for 21 locations representing major soybean regions of India.

TL;DR: The Advanced Regional Prediction System (ARPS) has been modified so as to simulate turbulent flow at very fine scale within and above vegetation canopies using a large-eddy simulation (LES) approach as mentioned in this paper.

TL;DR: In this article, the authors conducted measurements of net ecosystem production (NEP) over forest stands from 11 flux towers in sub-arctic, temperate, and tropical regions in East Asia between 2000 and 2005.

TL;DR: In this paper, a bottom-up multi-tower land cover aggregated scaling of CO2 flux to a 2000 km 2 regional flux estimate found June to August 2003 NEE, ER and GEP to be � 290 � 89, 408 � 48, and 698 � 73 gC m � 2, respectively.

TL;DR: In this article, a comparison of seasonal patterns of evapotranspiration (ET) between forest types shows increased ET corresponding with the atmospheric evaporative demand in two evergreen forest ecosystems, but not in both evergreen and two deciduous forest ecosystems.

TL;DR: In this paper, the performance of three RH-based empirical models to estimate leaf wetness duration (LWD) in four regions around the world that have different climate conditions was evaluated.