LUCC and Its Influences on LUCC and Its Influences on Regional NPP - - PowerPoint PPT Presentation
LUCC and Its Influences on LUCC and Its Influences on Regional NPP Regional NPP Maosong Liu, Liu, Shuqin Shuqin An, An, Maosong Xinfang Chen, Chen, Jinmin Jinmin Chen, Chi Chen, Chi Xu Xu, Chen Zhang , Chen Zhang Xinfang Nanjing
Maosong Maosong Liu, Liu, Shuqin Shuqin An, An, Xinfang Xinfang Chen, Chen, Jinmin Jinmin Chen, Chi Chen, Chi Xu Xu, Chen Zhang , Chen Zhang Nanjing University Nanjing University
Urbanization is one of the most important force driven LUCC, and affect many features of driven LUCC, and affect many features of vegetation, such as NPP, biodiversity, landscape vegetation, such as NPP, biodiversity, landscape quality. quality.
Urbanization is represented as urban-
suburb gradient belts, and can be studied by the gradient belts, and can be studied by the gradient analysis. gradient analysis.
The vegetation types and the FC affected by many many fractors fractors, especially economic. , especially economic.
NPP correlated with urbanization, and has very important influences on air quality, many important influences on air quality, many because the gas exchange. because the gas exchange.
Urban sprawl in Nanjing and Jiangyin
Ⅰ Ⅱ Ⅲ Ⅳ Ⅴ Ⅵ Ⅶ Ⅷ 覆盖率（% ）
PF/ PA TF/ TA M F/ M A
Forest succession of deciduous from bare land in the coming 200 year s 五角枫 臭椿 合欢 桤木 构树 山核桃 锥栗 板栗 朴树 皂荚 胡桃 枫香 石栎 马尾松 野柿 黄连木 化香 响叶杨 青檀 麻栎 白栎 桴树 栓皮栎 南京椴 榔榆 榆
0% 20% 40% 60% 80% 100% 1 11 21 31 41 51 61 71 81 91 101 111 121 131 141 151 161 171 181 191 201 YEAR NUM BER% Ul m us pum i l a l i nn Ul m us par vi f l or a j acq Ti l i a m i quel i ana m axi m Q uer cus var i abi l i s bl Q uer cus gl andul i f er a bl . Q uer cus al ba Q uer cus acut i ssi m a car r ut h Pt er ocel t i s t at ar i nowi i m axi Popul us adenopoda m axi m Pl at ycar ya st r obi l acea si ebe Pi st aci a chi nensi s bunge Pi ospyr os kaki . l Pi nus m assoni ana l am b Pal ber gi a hupeana hance Li t hocar pus gl aber nakai Li qui dam bar f or mForest Coverage changed along urban-suburb gradient Succession of forests
BEPS is a process based biogeochemistry model biogeochemistry model developed on the base of developed on the base of Forest Forest-
BGC model and it is refined by incorporating a more refined by incorporating a more advanced photosynthesis model advanced photosynthesis model ( (Farquar Farquar, 1988 )with a new , 1988 )with a new temporal and spatial scaling temporal and spatial scaling scheme and an advanced scheme and an advanced canopy radiation transfer model canopy radiation transfer model concerning of canopy concerning of canopy architecture of different architecture of different vegetation type. BEPS model vegetation type. BEPS model can calculate gross primary can calculate gross primary productivity (GPP), NPP and productivity (GPP), NPP and evapotranspiration evapotranspiration (ET) with the (ET) with the input data including land cove, input data including land cove, leaf area index (LAI), soil leaf area index (LAI), soil available water capacity (AWC) available water capacity (AWC) and daily meteorology data. and daily meteorology data.
Annual net primary production Photosynthesis & respiration Stomatal & mesophyll conductance Soil water balance NPP distribution
Land cover type
NDVI LAI
Biophysical parameters
Soil data (AWC)
Daily net primary production
Radiation (Daily) Temperature (Daily)
Precipitation (Daily)
Humidity (Daily)
Case study: NPP in Jiangyin Jiangyin
1991年LAI分布 2002年LAI分布
45.45 28.56 0.72 25.27 Forest A4 0.07 74.87 2.08 22.98 Cropland A3 0.05 29.69 61.44 8.82 Water A2 0.14 30.86 0.47 68.52 Residential A1 Transitional probability （Pij） (19912002) 859.25 539.91 13.59 477.63 Forest A4 49.75 50728.23 1411.2 15568.18 Cropland A3 5.81 3340.61 6912.71 992.67 Water A2 24.67 5526.36 83.63 12263.79 Residential A1 Transitional area（Aij） (19912002)
63.71 Amplitude (19912002)（%）
11403.82 Changed area 939.48 60135.11 8421.13 29302.27 Area in 2002 1890.38 67757.36 11251.8 17898.45 Area in 1991 Forest (A4) Cropland (A3) Water (A2) Residential (A1)
Biological parameters and initial
carbon content for various land covers in BEPS model
Foley (1994) and Matsushita, et al. (2002)
0.1 2.3 1.7 kgC/m2 Root carbon content
Foley (1994) and Matsushita, et al. (2002)
0.1 9.2 8 kgC/m2 Stem carbon content
Foley (1994) and Matsushita, et al. (2002)
0.1 0.5 0.3 kgC/m2 Leaf carbon content
Foley (1994) and Matsushita, et al. (2002)
0.0002 0.0002 0.0002 kgC/day/kg Root respiration coefficient
Foley (1994) and Matsushita, et al. (2002)
0.00005 0.00005 0.00005 kgC/day/kg Stem respiration coefficient
Foley (1994) and Matsushita, et al. (2002)
0.002 0.00267 0.00398 kgC/day/kg Leaf respiration coefficient
Hunt et al. (1996) and Matsushita, et al. (2002)
0.002 0.00225 0.0045 m/s Maximum stamotal conductance(H2O)
Chen (1996)and Chen and Cihlar (1995)
0.9 0.5 0.7 － Clump index references crop Conifer forest Broadleaved forest unit
Mean and total NPP in
in 1991a and 2002a
14.45 58.80 51.39 13.60 fraction（％） 116.71 4.61 4.43 107.67 Loss 691.16 3.23 4.19 683.74 2002 807.87 7.84 8.62 791.41 1991 Total NPP（Gg C y-1）
8.18 2.65 fraction（％）
64 31 Loss
718 1137 2002
782 1168 1991 Mean NPP（g Cm-2 y-1） total Broadleaved forest Conifer forest Cropland
1 2 3 4 5 6
针叶林 coni f er 阔叶林 br oadl eave 农田 agr i cul t ur e
叶面积指数 LAI
1991年 2002年
Variation of mean LAI of all vegetation type
Topography affect the spatial pattern of PP, mainly through light, water, nutrients, mainly through light, water, nutrients, temperature, winds. Especially soil water flow temperature, winds. Especially soil water flow direction. direction.
Topography affect the RS imageries, such as distortion, caused the shift of pixels, and so on. distortion, caused the shift of pixels, and so on. So, in NPP calculation based on RS data, we So, in NPP calculation based on RS data, we must consider the topography must consider the topography charactors charactors. .
BEPS and BEPS and Ter r ai nLab Ter r ai nLab ar e devel oped ar e devel oped by by J. C hen
i t h . BEPS not deal i ng w i t h soi l w at er hor i zont al f l ow but soi l w at er hor i zont al f l ow but Ter r ai nLab Ter r ai nLab di d. So w e use t hese di d. So w e use t hese t w
t w
ef f ect s of t opogr aphy on N PP. ef f ect s of t opogr aphy on N PP.
BEPS-
TerrainLab model model
Case study
1. 1.
Study area: Study area: Boahe Boahe watershed near watershed near Xi Xi’ ’an an, , area 3908 km area 3908 km2
2, annual precipitation 782mm,
, annual precipitation 782mm,
℃.
. 2. 2.
Data measured Data measured： ：LAI LAI， ，NPP NPP
3. 3.
Landsat Landsat TM TM， ，LAI LAI， ，Landcover Landcover, DEM , DEM
4. 4.
soil map, AWC soil map, AWC
5. 5.
Prec Prec., Temp. Humidity ., Temp. Humidity
4 types of model considerations types of model considerations
no no no no 4 4 yes yes no no 3 3 no no yes yes 2 2 yes yes yes yes 1 1 Topography on soil Topography on soil water lateral flow water lateral flow Topography on Topography on meteorology meteorology Scenario Scenario
Calculated and observed annul NPP R R2
2 =0.6418
=0.6418 Y=0.4626x+495.35 Y=0.4626x+495.35 4 4 R R2
2 =0.6513
=0.6513 Y=0.4675x+490.96 Y=0.4675x+490.96 3 3 R R2
2 =0.7611
=0.7611 Y=0.6639x+277.66 Y=0.6639x+277.66 2 2 R R2
2 =0.8151
=0.8151 Y=0.6403x+307.43 Y=0.6403x+307.43 1 1 R R2
2
Regression equation Regression equation scenario scenario
i st r i but i on of AN PP ( M
D i st r i but i on of AN PP ( M
ANPP varied between 400-920 gCm-2 yr-1,
is 741 gCm-2 yr-1 ，and in forest, ANPP varied in 700-880 gCm-2 yr-1 。
PP changed w i t h el evat i on and sl ope AN PP changed w i t h el evat i on and sl ope di r ect i on di r ect i on
ANPP increased with elevation while < 1350m but decreased when > 1350m and has a maximum at 1350m, while below 1900m, ANPP changed not more than 6% with slope direction, and nearly not changed regular while higher than 1900m.