NPP&GPP Of Temporal-geospatial Variation Of East Asia Terrestrial Ecosystem In1949-2008yr

To examine Net Primary Production（NPP） and Gross Primary Production （GPP） oftemporal-geospatial variation of Eastern Asia terrestrial ecosystem in1949-2008yr using theAtmosphere-Vegetation Interrelation Model II. Meanwhile, to recognize NPP,GPP andNPP/GPP ratio of Eastern Asia terrestrial ecosystem along geographical and climaticgradients and each typical terrestrial ecosystem using GIS Zonal Statistics which exploredgeospatial data （contains altitude, latitude and longitude）60-year average precipitationand temperature, and60-year average NPP density,GPP density,and NPP/GPP ratio dataafter simulation.The findings that:（1） Form1948to2008year, the Eastern Asia terrestrial ecosystemtotal NPP is943PgC(1PgC=1×10¹⁵gc),60-year annual average total of15.7±0.63Pg C, andits average NPP density633.36±25.56gC.m^-2.a^-1; total GPP ups to1680PgC,60-year annualaverage total is28.0±1.13Pg C; and its average NPP density1126.686±45.44gC.m^-2.a^-1;theNPP/GPP ratio is maximum with0.828,wih lowest ratio of0.004and its range of0.824,it hasan average NPP/GPP ratio value of0.604with minor variation （SD0.141）.（2）Multiyearaverage and annual total amounts of NPP and GPP both are the highest in autumn alongseasons, but the lowest value in Spring. For example, as NPP and GPP total amount as, theautumn value>the summer value> the winter value> the spring value.（3）For each typicalterrestrial ecosystem, there are different variation trend as the density of NPP and GPP.In fact, as just as NPP, Tree cover, broadleaved, evergreen>Tree cover, needle-leaved,evergreen>Tree cover, mixed leaf type>Cultivated and managed areas>Shrub Cover,closed-open, evergreen>Mosaic: Tree cover/other natural vegetation> Mosaic: Cropland/Treecover/other natural vegetation （MCTO）> Shrub Cover, closed-open, deciduous>Tree cover,broadleaved, deciduous, open>Tree cover, broadleaved, deciduous, closed>Tree cover,regular flooded, saline water>Tree cover, needle-leaved, deciduous>Tree cover, regularflooded, fresh water>Mosaic: Cropland/Shrub and/or grass cover>Regular flooded shruband/or herbaceous cover>Herbaceous cover, closed-open>Sparse herbaceous or sparse shrubcover>Shrub Cover, closed-open, deciduous. But for GPP, Tree cover, broadleaved,evergreen> Tree cover, needle-leaved, evergreen>Tree cover, broadleaved, deciduous,closed>Mosaic: Tree cover/other natural vegetation>Tree cover, regular flooded, salinewater>Tree cover, broadleaved, deciduous, open>Tree cover, mixed leaf type>Tree cover,regular flooded, fresh water>Shrub Cover, closed-open, evergreen>Shrub Cover, closed-open,deciduous>Cultivated and managed areas>Mosaic: Cropland/Tree cover/other naturalvegetation>Tree cover, needle-leaved, deciduous>Mosaic: Cropland/Shrub and/or grasscover>Regular flooded shrub and/or herbaceous cover>Herbaceous cover,closed-open>Sparse herbaceous or sparse shrub cover>Shrub Cover, closed-open,evergreen>Shrub Cover, closed-open, deciduous. As the NPP/GPP ratio,forest ecosystems had a lower value than other no-forest types, especially, Cultivated and managed areas with ahighest value.（4） Geographically, the NPP and GPP density decreased along latitude form10oS to55oN, but the ratio with a higher value only form10oN to55oN,and they exhibited aincresing trend along longtitude form60oE to150.5oE,but decreased along elevlation form-249m to7171m.（5）Climatically,the density NPP and GPP had a increased trend alongtemperature when it was between-6.35oc and27.37oc,but the ratio decreased;and emphrasizeda increasig trend along precipitation between0.0024Kg.m^-2.s^-1 and0.4525Kg.m^-2.s^-1, but theNPP/GPP ratio decreased yet.They showed that NPP, GPP and NPP/GPP ratio exhibited a pattern depending on themain climatic characteristics such as temperature and precipitation and geographical factorssuch as latitude and altitude. The findings of this research challenge the widely heldassumption that the NPP/GPP ratio is consistent regardless of ecosystem type.