数据说明
Ocean Net Primary Production (NPP)-CbPM
上传时间：2019-05-22 14:08:10 浏览次数：作者与来源：admin
SeaWIFS
Net primary production is the amount of photosynthetically fixed carbon available to the first heterotrophic level and, as such, is the relevant metric for addressing environmental questions ranging from trophic energy transfer to the influence of biological processes on carbon definition cycling (Lindeman 1942).
Unit: mg C/m2/day
Resolution: 9km pixel, monthly
Duration: Jul. 2002 to on-going.
Source: MODIS.
Version:
Processing: Original monthly mean products are shown.
For standard-VGPM:
The VGPM is a "chlorophyll-based" model that estimate NPP from chlorophyll using a temperature-dependent description of chlorophyll-specific photosynthetic efficiency.
Net primary production is the amount of photosynthetically fixed carbon available to the first heterotrophic level and, as such, is the relevant metric for addressing environmental questions ranging from trophic energy transfer to the influence of biological processes on carbon definition cycling (Lindeman 1942).
Unit: mg C/m2/day
Resolution: 9km pixel, monthly
Duration: Jul. 2002 to on-going.
Source: MODIS.
Version:
Processing: Original monthly mean products are shown.
For standard-VGPM:
The VGPM is a "chlorophyll-based" model that estimate NPP from chlorophyll using a temperature-dependent description of chlorophyll-specific photosynthetic efficiency.
|
NPP = Chla × Pbopt × day length × [0.66125 × PAR / ( PAR + 4.1 )] × Zeu
|
(1)
|
where Pbopt is the maximum carbon fixation rate within a water column (mg C· mg Chla-1·h-1), and is a function of sea surface temperature in the VGPM model (Equation (2)). PAR is the sea surface photosynthetically active radiation intensity (Enistien·m-2·d-1). Chla and Zeu are the sea surface chlorophyll-a concentration (mg·m-3) and euphotic layer depth (m), respectively.
|
if SST < -10℃, Pbopt=0;
else if SST < -1℃, Pbopt=1.13; else if SST > 28.5℃, Pbopt=4; else Pbopt= 1.2956 + 2.749e-1×SST + 6.17e-2×pow(SST,2) - 2.05e-2×pow(SST, 3) + 2.462e-3×pow(SST,4) - 1.348e-4×pow(SST,5) + 3.4132e-6×pow(SST,6) - 3.27e-8×pow(SST,7) |
(2)
|
where SST is the sea surface temperature (℃).
Known issues
It is worth noting that the products here are mainly used to estimate the NPP of the global ocean. When estimating the NPP of a regional area, it is necessary to use the measured NPP data to verify the applicability of the products presented here.
All the contents of this page are quoted from Oregon State University. All project
documentation and related publications can be found at the website:http://www.science.oregonstate.edu/ocean.productivity.
MODIS
Net primary production is the amount of photosynthetically fixed carbon available to the first heterotrophic level and, as such, is the relevant metric for addressing environmental questions ranging from trophic energy transfer to the influence of biological processes on carbon definition cycling (Lindeman 1942).
Unit: mg C/m2/day
Resolution: 9km pixel, monthly
Duration: Jul. 2002 to on-going.
Source: MODIS.
Version:
Processing: Original monthly mean products are shown.
For CbPM:
Development of the CbPM was motivated by the long-standing failure of chlorophyll-based modeling attempts to adequately account for natural variability in chlorophyll-specific photosynthetic efficiencies -- in other words, physiology.
The CbPM concept is one that abandons the traditional approach to NPP modeling. Instead of relating NPP to chlorophyll and Pbopt, the CbPM relates NPP to phytoplankton carbon biomass (C_phyto) and growth rate (u).
Known issues
It is worth noting that the products here are mainly used to estimate the NPP of the global ocean. When estimating the NPP of a regional area, it is necessary to use the measured NPP data to verify the applicability of the products presented here.
All the contents of this page are quoted from Oregon State University. All project
documentation and related publications can be found at the website:http://www.science.oregonstate.edu/ocean.productivity.
MODIS
Net primary production is the amount of photosynthetically fixed carbon available to the first heterotrophic level and, as such, is the relevant metric for addressing environmental questions ranging from trophic energy transfer to the influence of biological processes on carbon definition cycling (Lindeman 1942).
Unit: mg C/m2/day
Resolution: 9km pixel, monthly
Duration: Jul. 2002 to on-going.
Source: MODIS.
Version:
Processing: Original monthly mean products are shown.
For CbPM:
Development of the CbPM was motivated by the long-standing failure of chlorophyll-based modeling attempts to adequately account for natural variability in chlorophyll-specific photosynthetic efficiencies -- in other words, physiology.
The CbPM concept is one that abandons the traditional approach to NPP modeling. Instead of relating NPP to chlorophyll and Pbopt, the CbPM relates NPP to phytoplankton carbon biomass (C_phyto) and growth rate (u).
|
NPP =carbon × growth rate × volume function
|
(1)
|
For carbon in Equation (1)
Phytoplankton carbon biomass is assessed from particulate backscattering coefficients (bbp). Details of this relationship and its derivation is provided by Behrenfeld et al. 2005. Briefly, two primary contributors to bbp are recognized, (1) a relatively stable background concentration of small scattering particles and (2) a population of scattering particles that includes phytoplankton and those constituents that covary in abundance with phytoplankton concentration. Calculating phytoplankton carbon thus simply requires subtraction of the "background" contribution and scaling the remaining bbp to phytoplankton carbon biomass. This scaling coefficient is derived by adjusting its value until the range in satellite-based phytoplankton chlorophyll-to-carbon values are comparable to the range observed in the laboratory for a wide range of growth conditions and species. The resultant relationship is:
carbon = 13000 * (bbp - 0.00035)
For growth rate in Equation (1)
Phytoplankton growth rates are derived from satellite chlorophyll-to-carbon data. The fundamental model employed is relatively straightforward:
growth rate (u) = u(max) * f(N,T) * g(Ig)
In words, growth rate is equal to the maximum potential growth rate of a natural phytoplankton assemblage across all relevant temperatures [u(max)] corrected for the suppression of growth rate by nutrient and temperature stress [f(N,T)] and light limitation [g(Ig)].
Known issues
1. It is worth noting that the products here are mainly used to estimate the NPP of the global ocean. When estimating the NPP of a regional area, it is necessary to use the measured NPP data to verify the applicability of the products presented here.
2. CbPM products currently available through here are based on the updated model by Westberry et al. (2008).
All the contents of this page are quoted from Oregon State University. All project
documentation and related publications can be found at the website:http://www.science.oregonstate.edu/ocean.productivity.
VIIRS
Net primary production is the amount of photosynthetically fixed carbon available to the first heterotrophic level and, as such, is the relevant metric for addressing environmental questions ranging from trophic energy transfer to the influence of biological processes on carbon definition cycling (Lindeman 1942).
Unit: mg C/m2/day
Resolution: 9km pixel, monthly
Duration: Feb. 2012 to on-going.
Source: VIIRS.
Version:
Processing: Original monthly mean products are shown.
For CbPM:
Development of the CbPM was motivated by the long-standing failure of chlorophyll-based modeling attempts to adequately account for natural variability in chlorophyll-specific photosynthetic efficiencies -- in other words, physiology.
The CbPM concept is one that abandons the traditional approach to NPP modeling. Instead of relating NPP to chlorophyll and Pbopt, the CbPM relates NPP to phytoplankton carbon biomass (C_phyto) and growth rate (u).
Phytoplankton carbon biomass is assessed from particulate backscattering coefficients (bbp). Details of this relationship and its derivation is provided by Behrenfeld et al. 2005. Briefly, two primary contributors to bbp are recognized, (1) a relatively stable background concentration of small scattering particles and (2) a population of scattering particles that includes phytoplankton and those constituents that covary in abundance with phytoplankton concentration. Calculating phytoplankton carbon thus simply requires subtraction of the "background" contribution and scaling the remaining bbp to phytoplankton carbon biomass. This scaling coefficient is derived by adjusting its value until the range in satellite-based phytoplankton chlorophyll-to-carbon values are comparable to the range observed in the laboratory for a wide range of growth conditions and species. The resultant relationship is:
carbon = 13000 * (bbp - 0.00035)
For growth rate in Equation (1)
Phytoplankton growth rates are derived from satellite chlorophyll-to-carbon data. The fundamental model employed is relatively straightforward:
growth rate (u) = u(max) * f(N,T) * g(Ig)
In words, growth rate is equal to the maximum potential growth rate of a natural phytoplankton assemblage across all relevant temperatures [u(max)] corrected for the suppression of growth rate by nutrient and temperature stress [f(N,T)] and light limitation [g(Ig)].
Known issues
1. It is worth noting that the products here are mainly used to estimate the NPP of the global ocean. When estimating the NPP of a regional area, it is necessary to use the measured NPP data to verify the applicability of the products presented here.
2. CbPM products currently available through here are based on the updated model by Westberry et al. (2008).
All the contents of this page are quoted from Oregon State University. All project
documentation and related publications can be found at the website:http://www.science.oregonstate.edu/ocean.productivity.
VIIRS
Net primary production is the amount of photosynthetically fixed carbon available to the first heterotrophic level and, as such, is the relevant metric for addressing environmental questions ranging from trophic energy transfer to the influence of biological processes on carbon definition cycling (Lindeman 1942).
Unit: mg C/m2/day
Resolution: 9km pixel, monthly
Duration: Feb. 2012 to on-going.
Source: VIIRS.
Version:
Processing: Original monthly mean products are shown.
For CbPM:
Development of the CbPM was motivated by the long-standing failure of chlorophyll-based modeling attempts to adequately account for natural variability in chlorophyll-specific photosynthetic efficiencies -- in other words, physiology.
The CbPM concept is one that abandons the traditional approach to NPP modeling. Instead of relating NPP to chlorophyll and Pbopt, the CbPM relates NPP to phytoplankton carbon biomass (C_phyto) and growth rate (u).
|
NPP =carbon × growth rate × volume function
|
(1)
|
For carbon in Equation (1)
Phytoplankton carbon biomass is assessed from particulate backscattering coefficients (bbp). Details of this relationship and its derivation is provided by Behrenfeld et al. 2005. Briefly, two primary contributors to bbp are recognized, (1) a relatively stable background concentration of small scattering particles and (2) a population of scattering particles that includes phytoplankton and those constituents that covary in abundance with phytoplankton concentration. Calculating phytoplankton carbon thus simply requires subtraction of the "background" contribution and scaling the remaining bbp to phytoplankton carbon biomass. This scaling coefficient is derived by adjusting its value until the range in satellite-based phytoplankton chlorophyll-to-carbon values are comparable to the range observed in the laboratory for a wide range of growth conditions and species. The resultant relationship is:
carbon = 13000 * (bbp - 0.00035)
For growth rate in Equation (1)
Phytoplankton growth rates are derived from satellite chlorophyll-to-carbon data. The fundamental model employed is relatively straightforward:
growth rate (u) = u(max) * f(N,T) * g(Ig)
In words, growth rate is equal to the maximum potential growth rate of a natural phytoplankton assemblage across all relevant temperatures [u(max)] corrected for the suppression of growth rate by nutrient and temperature stress [f(N,T)] and light limitation [g(Ig)].
Known issues
1. It is worth noting that the products here are mainly used to estimate the NPP of the global ocean. When estimating the NPP of a regional area, it is necessary to use the measured NPP data to verify the applicability of the products presented here.
2. CbPM products currently available through here are based on the updated model by Westberry et al. (2008).
All the contents of this page are quoted from Oregon State University. All project
documentation and related publications can be found at the website:http://www.science.oregonstate.edu/ocean.productivity.
Phytoplankton carbon biomass is assessed from particulate backscattering coefficients (bbp). Details of this relationship and its derivation is provided by Behrenfeld et al. 2005. Briefly, two primary contributors to bbp are recognized, (1) a relatively stable background concentration of small scattering particles and (2) a population of scattering particles that includes phytoplankton and those constituents that covary in abundance with phytoplankton concentration. Calculating phytoplankton carbon thus simply requires subtraction of the "background" contribution and scaling the remaining bbp to phytoplankton carbon biomass. This scaling coefficient is derived by adjusting its value until the range in satellite-based phytoplankton chlorophyll-to-carbon values are comparable to the range observed in the laboratory for a wide range of growth conditions and species. The resultant relationship is:
carbon = 13000 * (bbp - 0.00035)
For growth rate in Equation (1)
Phytoplankton growth rates are derived from satellite chlorophyll-to-carbon data. The fundamental model employed is relatively straightforward:
growth rate (u) = u(max) * f(N,T) * g(Ig)
In words, growth rate is equal to the maximum potential growth rate of a natural phytoplankton assemblage across all relevant temperatures [u(max)] corrected for the suppression of growth rate by nutrient and temperature stress [f(N,T)] and light limitation [g(Ig)].
Known issues
1. It is worth noting that the products here are mainly used to estimate the NPP of the global ocean. When estimating the NPP of a regional area, it is necessary to use the measured NPP data to verify the applicability of the products presented here.
2. CbPM products currently available through here are based on the updated model by Westberry et al. (2008).
All the contents of this page are quoted from Oregon State University. All project
documentation and related publications can be found at the website:http://www.science.oregonstate.edu/ocean.productivity.
