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[1] The evapotranspiration (ET) from all Canadian landmass in 1996 is estimated at daily steps and 1 km resolution using a process model named boreal ecosystem productivity simulator (BEPS). The model is driven by remotely sensed leaf area index and land cover maps as well as soil water holding capacity and daily meteorological data. All the major ET components are considered: transpiration from vegetation, evaporation of canopy-intercepted rainfall, evaporation from soil, sublimation of snow in winter and in permafrost and glacier areas, and sublimation of canopy-intercepted snow. In forested areas the transpiration from both the overstory and understory vegetation is modeled separately. The Penman-Monteith method was applied to sunlit and shaded leaf groups individually in modeling the canopy-level transpiration, a methodological improvement necessary for forest canopies with considerable foliage clumping. The modeled ET map displays pronounced east-west and north-south gradients as well as detailed variations with cover types and vegetation density. It is estimated that for a relative wet year of 1996, the total ET from all Canada's landmass (excluding inland waters) was 2037 km3. If compared with the total precipitation of 5351 km3 based on the data from a medium range meteorological forecast model, the ratio of ET to precipitation was 38%. The ET averaged over Canadian land surface was 228 mm/yr in 1996, partitioned into transpiration of 102 mm yr−1 and evaporation and sublimation of 126 mm yr−1. Forested areas contributed the largest fraction of the total national ET at 59%. Averaged for all cover types, transpiration accounted for 45% of the total ET, while in forested areas, transpiration contributed 51% of ET. Modeled results of daily ET are compared with eddy covariance measurements at three forested sites with a r2 value of 0.61 and a root mean square error of 0.7 mm/day.

This is the second of two Chapters addressing the use of coarse resolution satellite data for large-scale applications in forestry. Here we review the use of AVHRR and VGT data for characterizing forest structure and carbon uptake. It is assumed that most of the observation artifacts were removed from the satellite data through prior processing, thus the corrected data represent intrinsic electromagnetic properties of the surface targets. Both forest structural properties (fractional composition and change in land cover, leaf area index, active fires and burns) and functional behaviour (net primary productivity, net ecosystem productivity, net biome productivity) are reviewed, based on research carried out for the forests of Canada.

Forests provide essential economic and ecological services, and their essential role in the planetary system is being increasingly recognized. In parallel, the demand for timely and accurate information on the status and function of the forest biome, for a variety of purposes, is also increasing. While traditionally forest information was gathered in situ or through air photography, the role of satellite remote sensing is becoming central because of the need to match the spatial and temporal scales of observations to those of the key forest processes. In this Chapter, we briefly review (i) data processing issues underpinning the use of ‘coarse resolution’ optical satellite data for terrestrial studies, and (ii) an application to land cover mapping at the national level. An accompanying Chapter (13) describes the use of the processed data sets to derive information on biophysical parameters, land cover change, and carbon uptake. The discussion draws heavily on our work in Canada but the findings are applicable to similar geographic and ecoclimatic conditions elsewhere.

Helicopter-based radiometric measurements of forested sites acquired during the Boreal Ecosystem-Atmosphere Study (BOREAS) were used to examine the spatial, temporal, and spectral variability in surface reflectance and vegetation indices (VI), including the normalized difference vegetation index (NDVI) and the simple ratio (SR), and for comparison with surface cover and fluxes. In this analysis, the sensors, which were employed during all three intensive field campaigns (IFC) of 1994, consisted of an eight-channel modular multiband radiometer (MMR), ground-based Sun photometer used for atmospheric correction, and LICOR LAI-2000, hemispherical photographs, and a ceptometer for retrieval of surface biophysical variables. Means and coefficients of variation were calculated and linear regression analysis performed on reflectances, VIs, and surface variables over the entire data set and as a function of season and cover type. Surface biophysical variables included leaf area index (LAI), effective LAI, and the fraction of absorbed photosynthetically-active radiation (green fAPAR). While each dominant species displayed recognizable reflectance spectra, variability in reflectance, which was high in every channel, was most likely strongly influenced by understory and ground reflectances, and by atmospheric effects. Of the eight MMR bands, those most responsive to surface variations were the third and second middle infrared (IR) (2.08-2.37 and 1.57-1.80 /spl mu/m, respectively), the red (0.63-0.68 /spl mu/m), and the blue (0.45-0.52 /spl mu/m). Of the two VIs examined, the authors' results showed that the NDVI offered more predictive information than the SR regarding temporal and spatial variations in surface characteristics. Linear regression analyses between the surface biophysical measurements and the helicopter reflectances and VIs resulted in low r/sup 2/ values (consistently

An investigation of directional reflectance of boreal forests is conducted using airborne POLDER (1994) and ground-based PARABOLA measurements (1995) and the 4-Scale model (1997). The model simulates well the pronounced hotspots observed by POLDER and the slight bowl shape in the forward scattering direction observed by PARABOLA. The model is also used to demonstrate the importance of branch architecture in the directionality of NDVI calculated from the red and near infrared reflectance.

A new moisture adjusted vegetation index (MAVI) is proposed using the red, near infrared, and shortwave infrared (SWIR) reflectance in band-ratio form in this paper. The effectiveness of MAVI in retrieving leaf area index (LAI) is investigated using Landsat-5 data and field LAI measurements in two forest and two grassland areas. The ability of MAVI to retrieve forest LAI under different background conditions is further evaluated using canopy reflectance of Jack Pine and Black Spruce forests simulated by the 4-Scale model. Compared with several commonly used two-band vegetation index, such as normalized difference vegetation index, soil adjusted vegetation index, modified soil adjusted vegetation index, optimized soil adjusted vegetation index, MAVI is a better predictor of LAI, on average, which can explain 70% of variations of LAI in the four study areas. Similar to other SWIR-related three-band vegetation index, such as modified normalized difference vegetation index (MNDVI) and reduced simple ratio (RSR), MAVI is able to reduce the background reflectance effects on forest canopy LAI retrieval. MAVI is more suitable for retrieving LAI than RSR and MNDVI, because it avoids the difficulty in properly determining the maximum and minimum SWIR values required in RSR and MNDVI, which improves the robustness of MAVI in retrieving LAI of different land cover types. Moreover, MAVI is expressed as ratios between different spectral bands, greatly reducing the noise caused by topographical variations, which makes it more suitable for applications in mountainous area.

Remote sensing of forested regions depends greatly on the Sun and view geometries under which images are taken. A forest canopy radiative-transfer model based on detailed tree architecture named "4-scale" has been used in recent years to study the influence of boreal forest properties such as leaf area index (LAI), crown size, branches architecture, tree grouping, etc, on the bidirectional reflectance of different canopies. This paper presents updated results using the latest version of the model that contains a new multiple-scattering scheme that depends on the crown architecture as well as the spatial distribution of the trees. New simulations of ground-based PARABOLA and airborne POLDER reflectances in the red and near-infrared bands are shown, and the mechanisms controlling NDVI directionality are discussed The use of 4-Scale for directional corrections of airborne CASI data will also be shown. These results have implications on inversion techniques based on the shadow and sunlit proportions for the retrieval of LAI.

BRFs of boreal forest conifer canopies were observed and modelled using the MODIS BRDF/Albedo algorithms which included a recently derived Inverse 4-Scale Model. Derived BRDF functions show reasonable agreement with observed BRF. As many inverse models are limited to handling specific situations (such as high or low LAI), the Inverse 4-Scale Model was derived to allow one model use for investigation of a wider variety of canopy conditions.

In this study, we first numerically investigate the appearance and properties of multiple Fano resonances in two-dimensional hexagonal non-close-packed arrays of symmetric metallic shells. The coexistence of broad sphere-like plasmon modes formed from the near-field interaction between the individual sphere plasmons and substantially narrower void plasmon modes supported by the inner surface of the individual shell resonant over the same range of energies can produce such Fano resonances. In particular, void and sphere-like plasmon modes of different angular momentum could directly interact without the need of symmetry breaking in the structure. A cost-effective colloidal crystal templating method is utilized to prepare the arrays of the metallic shells with small openings. The effect of the symmetry breaking on the Fano resonances in metallic cup arrays is experimentally and numerically investigated. Further tunability on the Fano resonances is gained by changing the size of the inner dielectric core, hence changing the moment of the void plasmon modes and consequently the resonance frequency. By adopting the polymer dielectric core with gain materials, our study may offer realizable experimental opportunities towards subwavelength low threshold plasmonic lasing.

The near infrared transmission of corrugated metal films deposited on hetero-colloidal crystals is investigated. The transmission response of the quasi-three-dimensional (quasi-3D) metal film is modified by controlling the nominal thickness of a dielectric layer pre-deposited on the top surface of the colloidal crystal to form a new hetero-colloidal crystal. An extraordinary optical transmission (EOT) phenomenon could be presented in such metallodielectric (MD) architectures. We have found that the main transmission peak is suppressed as the thickness of the intercalated dielectric layer is increased. We propose that the observed EOT is a result of constructive interference between a localized sphere-like plasmon mode and an index-guided eigen mode mainly confined in the colloidal crystal, which is confirmed by our numerical simulations. Based on the MD microstructures, a distinct plasmon sensitivity response difference is achieved, which indicates potential applications for biochemical sensing.

Based on the contra-directional coupling, a composite structure consisting of two coupled metal-insulator-metal (MIM) waveguides is proposed to act as an attractive plasmonic reflector. By introducing a defect into one of the MIM waveguides, we show that such a composite structure can be operated as a plasmonic nanocavity with a high quality factor. Both symmetric and anti-symmetric cavity modes are supported in the plasmonic cavity, and their resonance frequencies can be tuned by controlling the defect width. The present structures could have a significant impact for potential applications such as surface plasmon mirrors, filters and solid-state cavity quantum electrodynamics.

We numerically study the effect of the symmetry breaking on surface plasmon (SP) modes in two-dimensional dense arrays of truncated metal nanoshells (nanocups), by investigating light transmission through the arrays. We show that localized spherelike and voidlike Mie SP modes, and delocalized Bragg-type SP modes in complete nanoshell arrays become progressively weak and finally disappear when the opening angle of nanocups is increased to tens of degrees. Under higher degree of symmetry breaking, however, the coupling between spherelike and voidlike SP modes leads to an enhancement of SP resonances even though these modes are weakly excited, due to the large optical cross section of voidlike modes. Energy variations of the hybridized mode versus the opening angle are well predicted using a plasmon standing wave model. Furthermore, disappeared Bragg-type SP modes could be re as a result of near-field coupling via hot spots around the rims of nanocups.

The current mountain pine beetle (Dendroctonus ponderosae Hopkins) outbreak, whichbeganin1999,continuestobetheleadingcauseofpinetreemortalityinBritishColumbia. Information regarding the location and spatial extent of the current attack is required for mit- igating practices and forest inventory updates. This information is available from spaceborne observations. Unfortunately, the monitoring of the mountain pine beetle outbreak using remote sensing is usually limited to the visible stage at which the expansion of the attack beyond its initial hosts is unpreventable. The disruption of the sap flow caused by a blue-staining fungi carried by the beetles leads to: 1. a decrease in the amount of liquid water stored in the canopy, 2. anincrease incanopy temperature, and 3. anincrease inshortwave infraredreflectance shortly after the infestation. As such, the potential for early beetle detection utilizing thermal remote sensing is possible. Here we present a first attempt to detect a mountain pine beetle attack at its earliest stage (green attack stage when the foliage remains visibly green after the attack) using the temperature condition index (TCI) derived from Landsat ETM+ imagery over an affected area in British Columbia. The lack of detailed ground survey data of actual green attack areas limits the accuracy of this research. Regardless, our results show that TCI has the ability to differentiate between affected and unaffected areas in the green attack stage, and thus it provides information on the possible epicenters of the attack and on the spatial extent of the outbreak at later stages (red attack and gray attack). Furthermore, we also developed a moisture condition index (MCI) using both shortwave infrared and thermal infrared measurements. The MCI index is shown to be more effective than TCI in detecting the green attack stage and provides a more accurate picture of beetle spread patterns. C 2011 Society of Photo-Optical Instrumentation Engineers

The variations of soil water content (SWC) and its influences on the carbon (C) cycle in Canada's forests and wetlands were studied through model simulations using the Integrated Terrestrial Ecosystem Carbon (InTEC) model. It shows that Canada's forests and wetlands experienced spatially and temporally heterogeneous changes in SWC from 1901 to 2000. SWC changes caused average NPP to decrease 40.8 Tg C yr -1 from 1901 to 2000, whereas the integrated effect of non-disturbance factors (climate change, CO2 fertilization and N deposition) enhanced NPP by 9.9%. During 1981–2000, the reduction of NPP caused by changes in SWC was 58.1 Tg C yr -1 whereas non-disturbance factors together caused NPP to increase by 16.6%. SWC changes resulted in an average increase of 4.1 Tg C yr -1 in the net C uptake during 1901–2000, relatively small compared with the enhancement in C uptake of 50.2 Tg C yr -1 by the integrated effect of non-disturbance factors. During 1981–2000, changes in SWC caused a reduction of 3.8 Tg C yr -1 in net C sequestration whereas the integrated factors increased net C sequestration by 54.1 Tg C yr -1 . Increase in SWC enhanced C sequestration in all ecozones. DOI: 10.1111/j.1600-0889.2010.00459.x

A nested inverse modelling system was developed for estimating carbon fluxes of 30 regions in North America and 20 regions for the rest of the globe. Monthly inverse modelling was conducted using CO 2 concentration measurements of 3 yr (2001–2003) at 88 sites. Inversion results show that in 2003 the global carbon sink is −2.76 ± 0.55 Pg C. Oceans and lands are responsible for 88.5% and 11.5% of the sink, respectively. Northern lands are the largest sinks with North America contributing a sink of −0.97 ± 0.21 Pg C in 2003, of which Canada's sink is −0.34 ± 0.14 Pg C. For Canada, the inverse results show a spatial pattern in agreement, for the most part, with a carbon source and sink distribution map previously derived through ecosystem modelling. However, discrepancies in the spatial pattern and in flux magnitude between these two estimates exist in certain regions. Numerical experiments with a full covariance matrix, with the consideration of the error structure of the a priori flux field based on meteorological variables among the 30 North America regions, resulted in a small but meaningful improvement in the inverted fluxes. Uncertainty reduction analysis suggests that new observation sites are still needed to further improve the inversion for these 30 regions in North America. DOI: 10.1111/j.1600-0889.2006.00235.x

Atmospheric CO 2 measurements show strong synoptic variability. To understand the contribution of the synoptic signals on atmospheric CO 2 inversion, we simulate the cases of biospheric fluxes with and without synoptic variations (referred to as ‘Synoptic’ and ‘Reference’, respectively) using an atmospheric transport model, and then perform inversion analyses with these biospheric CO 2 concentration fields. Results show the monthly and annually averaged CO 2 concentration anomalies (Synoptic–Reference) are functions of the distance from the continental biospheric source regions. Remote sites (like Mauna Loa) show averaged monthly amplitude of ∼0.2 ppm, while continental sites show averaged monthly amplitudes of 1–2 ppm with maximum monthly amplitudes up to 7 ppm. Spatial scales of these monthly mean synoptic anomaly patterns may exceed 1000 km. These CO 2 concentration patterns are the results of the interaction of the synoptic CO 2 flux field and atmospheric transport, and may be referred to as the synoptic Rectifier Effect. Inversion CO 2 fluxes for 1992–1995 are obtained using biospheric background fields with and without synoptic biospheric flux variations. The maximum magnitude differences in estimated monthly flux for land and ocean regions are ∼0.4 and ∼0.2 GtC month −1 , respectively. The average land sink increases by 0.19 GtC yr −1 while the average ocean sink decreases by 0.30 GtC yr −1 . DOI: 10.1111/j.1600-0889.2006.00219.x

Stable isotopes of CO 2 contain unique information on the biological and physical processes that exchange CO 2 between terrestrial ecosystems and the atmosphere. Ecosystem exchange of carbon isotopes with the atmosphere is correlated diurnally and seasonally with the planetary boundary layer (PBL) dynamics. The strength of this kind of covariation affects the vertical gradient of δ 13 C and thus the global δ 13 C distribution pattern. We need to understand the various processes involved in transport/diffusion of carbon isotope ratio in the PBL and between the PBL and the biosphere and the troposphere. In this study, we employ a one-dimensional vertical diffusion/transport atmospheric model (VDS), coupled to an ecosystem isotope model (BEPS-EASS) to simulate dynamics of 13 CO 2 in the PBL over a boreal forest region in the vicinity of the Fraserdale (FRD) tower (49°52′29.9″N, 81°34′12.3″W) in northern Ontario, Canada. The data from intensive campaigns during the growing season in 1999 at this site are used for model validation in the surface layer. The model performance, overall, is satisfactory in simulating the measured data over the whole course of the growing season. We examine the interaction of the biosphere and the atmosphere through the PBL with respect to δ 13 C on diurnal and seasonal scales. The simulated annual mean vertical gradient of δ 13 C in the PBL in the vicinity of the FRD tower was about 0.25‰ in 1999. The δ 13 C vertical gradient exhibited strong diurnal (29%) and seasonal (71%) variations that do not exactly mimic those of CO 2 . Most of the vertical gradient (96.5%±) resulted from covariation between ecosystem exchange of carbon isotopes and the PBL dynamics, while the rest (3.5%±) was contributed by isotopic disequilibrium between respiration and photosynthesis. This disequilibrium effect on δ 13 C of CO 2 dynamics in PBL, moreover, was confined to the near surface layers (less than 350 m). DOI: 10.1111/j.1600-0889.2006.00213.x

Estimating global carbon fluxes by inverting atmospheric CO 2 through the use of atmospheric transport models has shown the importance of the covariance between biospheric fluxes and atmospheric transport on the carbon budget. This covariance or coupling occurs on many time scales. This study examines the coupling of the biosphere and the atmosphere on the meso- and synoptic scales using a coupled atmosphere–biosphere regional model covering Canada. The results are compared with surface and light aircraft measurement campaigns at two boreal forest sites in Canada (Fraserdale and BERMS). Associated with cold and warm frontal features, the model results showed that the biospheric fluxes are strongly coupled to the atmosphere through radiative forcing. The presence of cloud near frontal regions usually results in reduced photosynthetic uptake, producing CO 2 concentration gradients across the frontal regions on the order of 10 parts per million (ppm). Away from the frontal region, the biosphere is coupled to the mesoscale variations in similar ways, resulting in mesoscale variations in CO 2 concentrations of about 5 ppm. The CO 2 field is also coupled strongly to the atmospheric dynamics. In the presence of frontal circulation, the CO 2 near the surface can be transported to the mid to upper troposphere. Mesoscale circulation also plays a significant part in transporting the CO 2 from the planetary boundary layer (PBL) to the mid-troposphere. In the absence of significant mesoscale or synoptic scale circulation, the CO 2 in the PBL has minimal exchange with the free troposphere, leading to strong gradients across the top of the PBL. We speculate that the ubiquity of the common synoptic and mesoscale processes in the atmosphere may contribute significantly to the rectifier effect and hence CO 2 inversion calculations. DOI: 10.1111/j.1600-0889.2004.00104.x

Annual spatial distributions of carbon sources and sinks in Canada's forests at 1 km resolution are computed for the period from 1901 to 1998 using ecosystem models that integrate remote sensing images, gridded climate, soils and forest inventory data. GIS-based fire scar maps for most regions of Canada are used to develop a remote sensing algorithm for mapping and dating forest burned areas in the 25 yr prior to 1998. These mapped and dated burned areas are used in combination with inventory data to produce a complete image of forest stand age in 1998. Empirical NPP age relationships were used to simulate the annual variations of forest growth and carbon balance in 1 km pixels, each treated as a homogeneous forest stand. Annual CO2 flux data from four sites were used for model validation. Averaged over the period 1990–1998, the carbon source and sink map for Canada's forests show the following features: (i) large spatial variations corresponding to the patchiness of recent fire scars and productive forests and (ii) a general south-to-north gradient of decreasing carbon sink strength and increasing source strength. This gradient results mostly from differential effects of temperature increase on growing season length, nutrient mineralization and heterotrophic respiration at different latitudes as well as from uneven nitrogen deposition. The results from the present study are compared with those of two previous studies. The comparison suggests that the overall positive effects of non-disturbance factors (climate, CO2 and nitrogen) outweighed the effects of increased disturbances in the last two decades, making Canada's forests a carbon sink in the 1980s and 1990s. Comparisons of the modeled results with tower-based eddy covariance measurements of net ecosystem exchange at four forest stands indicate that the sink values from the present study may be underestimated.DOI: 10.1034/j.1600-0889.2003.00036.x

Optical instruments currently available for measuring the leaf-area index (LAI) of a plant canopy all utilize only the canopy gap-fraction information. These instruments include the Li-Cor LAI-2000 Plant Canopy Analyzer, Decagon, and Demon. The advantages of utilizing both the canopy gap-fraction and gap-size information are shown. For the purpose of measuring the canopy gap size, a prototype sunfleck-LAI instrument named Tracing Radiation and Architecture of Canopies (TRAC), has been developed and tested in two pure conifer plantations, red pine (Pinus resinosa Ait.) and jack pine (Pinus banksiana Lamb). A new gap-size-analysis theory is presented to quantify the effect of canopy architecture on optical measurements of LAI based on the gap-fraction principle. The theory is an improvement on that of Lang and Xiang [Agric. For. Meteorol. 37, 229 (1986)]. In principle, this theory can be used for any heterogeneous canopies.

Global surface temperature change is one of the most important aspects in global climate change research. In this study, in order to overcome shortcomings of traditional observation methods in meteorology, a new method is proposed to calculate global mean surface temperature based on remote sensing data. We found that (1) the global mean surface temperature was close to 14.35 °C from 2001 to 2012, and the warmest and coldest surface temperatures of the global in the recent twelve years occurred in 2005 and 2008, respectively; (2) the warmest and coldest surface temperatures on the global land surface occurred in 2005 and 2001, respectively, and on the global ocean surface in 2010 and 2008, respectively; and (3) in recent twelve years, although most regions (especially the Southern Hemisphere) are warming, global warming is yet controversial because it is cooling in the central and eastern regions of Pacific Ocean, northern regions of the Atlantic Ocean, northern regions of China, Mongolia, southern regions of Russia, western regions of Canada and America, the eastern and northern regions of Australia, and the southern tip of Africa. The analysis of daily and seasonal temperature change indicates that the temperature change is mainly caused by the variation of orbit of celestial body. A big data model based on orbit position and gravitational-magmatic change of celestial body with the solar or the galactic system should be built and taken into account for climate and ecosystems change at a large spatial-temporal scale.

The ability to make repeated measurements of the changing Earth's surface is the principal advantage of satellite remote sensing. To realize its potential, it is necessary that true surface changes be isolated in the satellite signal from other effects which also influence the signal. In this study, we explore the magnitude of such effects in composite NOAA advanced very high resolution radiometer (AVHRR) images with a pixel spacing of 1 km. A compositing procedure is frequently used in the preparation of data sets for land biosphere studies to minimize the effect of clouds. However, the composite images contain residual artifacts which make it difficult to compare measurements at various times. We have employed a 4-year (1993–1996) AVHRR data set from NOAA 11 and 14 covering the Canadian landmass and corrected these data for the influence of the remaining clouds (full pixel or subpixel), atmospheric attenuation, and bidirectional reflectance. We have found that such corrections are essential for studies of interannual variations. The magnitude of the interannual signal varied with the AVHRR channel, land cover type, and satellite sensor but it was reduced by a factor of 2 to 8 between top of the atmosphere and the normalized surface reflectance. The remaining variations consisted of true interannual signal and the residual noise in the data (including sensor calibration) which was not removed by the correction process. Assuming that barren or sparsely vegetated land in northern Canada has not changed over the 4-year period, the mean residual uncertainty in surface reflectance of the selected sites was 0.012 for AVHRR channel 1, 0.042 for channel 2, and 0.068 for the normalized difference vegetation index (NDVI). These values decreased to 0.011, 0.024 and 0.038, respectively, when excluding 1994 data because their atmospheric and bidirectional corrections were hampered by high solar zenith angles (mean values above 55° in all 1994 composite periods). The errors could be further reduced by more refined corrections for bidirectional and atmospheric effects. The impact of the uncertainty of channel 1 and 2 measurements is also significantly diminished by using ratio indices such as the NDVI. It is concluded that interannual variability exceeding 0.015–0.038 in NDVI (averaged over multiple pixels) can be detected for similar data sets and conditions, provided that sensor calibration does not introduce additional errors. Since such errors can be large for some conditions and applications, the importance of accurate sensor calibration cannot be overemphasized.

Spatial scaling is of particular importance in remote sensing applications to terrestrial ecosystems where spatial heterogeneity is the norm. Surface parameters derived at different resolutions can be considerably different even though they are derived using the same algorithms or models. This article addresses issues related to spatial scaling of net primary productivity (NPP). The main objective is to develop algorithms for spatial scaling of NPP using subpixel information. NPP calculations at 30 m and 1km resolutions were performed using the Boreal Ecosystem Productivity Simulator (BEPS). The area of interest is near Fraserdale, Ontario. It is found from this investigation that lumped (coarse resolution) calculations can be considerably biased (up to 64 %) from distributed (fine resolution) case, suggesting that global and regional NPP maps can be biased by the same amount if surface heterogeneity within the mapping resolution is ignored. The bias is negative when conifer-labeled pixels contain considerable deciduous forests. Due to relatively high and variable NPP values of open land areas with growing grasses, the bias is negative when deciduous-labeled pixels are mixed with open land. There is no trend between the biasness and open land fractions within conifer-labeled pixels. Based on these results, algorithms for removing these biases in lumped NPP are developed using subpixel land cover information.