Valuing scarcity of coastal wetland – a conceptual model

(unfinished)Dr ZOU Xinqing

Background

• National level: 120 million ha cultivated land – red line

• Rapid urbanization process in recent 2 decades

• Jiangsu province: 0.18 million ha land resources are needed before 2020.

Reclamtion plan before 2020

Yancheng coastal wetland

KE, C.-Q., 2011, Regional Environmental Change, 11, 161-173

Land use changes in YNNR

KE, C.-Q., 2011, Regional Environmental Change, 11, 161-173

Land use changes in YNNR

Valuing eco-services

• 生态系统服务功能估算的背景– 上世纪 70 年代 (Gosselink, J. G., Odum, E. P.

and Pope, R. M. 1974. Meo, M.,et al 1975. )– Costanza, 1997 的生态系统评估：

• 17 项生态服务功能，包括气体调节、干扰调节、废弃物处理、养分循环等等

• 地球生态系统生态服务功能总价 :33 万亿美元• 其中 63% 来自海洋（ 20.9 万亿美元）• 其中 10.6 万亿来自海岸带

Spartina flat

Reclamation

Coastal wetland eco-services

• Provisioning services• Regulating services

– Heay metal absorbance – Nutrient absorbance (N, P) – Coastal zone robustness– Atmosphere regulation

• Cultural services• Supporting services

Provisioning services

Vpro=2439 ～ 4146 $/hm2/yr

N, P absorbance through sediments

N, P absorbance flux (g/m2/yr)

Sample TOC TN TP

ZWG01 201.02 22.83 23.39

ZWG02 242.77 30.77 32.61

ZWG03 151.35 17.67 24.09

ZWG04 225.08 28.29 25.43

N, P absorbance through vegetation (Spartina alterniflora)• 互花米草植被

– 根部对 TN 的吸收是 12.99 ～ 18.05 g/m2/yr ，– 地上部分对 TN 的吸收是 16 ～ 27.87 g/m2/yr ；– 根部对 TP 的吸收是 1.68 ～ 1.98 g/m2/yr ，– 地上部分对 TP 的吸收是 3.39 ～ 6.08 g/m2/yr 。

• 植被对 TN 的吸收总量是 28.99 ～ 45.92 g/m2/yr ，

• 对 TP 吸收的总量是 5.08 ～ 8.07 g/m2/yr 。

Valuing N, P absorbance

• Vnu=∑(Fi×Ti)

– 其中 Vnu 是湿地吸收富营养物的经济价值，单位是： $/hm2/yr

– Fi 是湿地吸收富营养物 i 的通量，单位是 g/hm2/yr

– Ti 是处理富营养物 i 的平均成本，单位是 $/g

• 互花米草湿地对 N 、 P 吸收的总的经济价值是 360 ～ 4366 $/ hm2/yr

Coastal zone robustness

互花 米 草宽 m度（ ）

4. 5m高

5. 1m高

5. 7m高

6. 3m高

012345678 100 200 300 400

7. 5m高

6. 9m高

m海堤高度（ ）

10m 12cm每 互花 米 草消浪

互花 米 草宽 m度（ ）

4. 5m高

5. 1m高

5. 7m高

6. 3m高

012345678 200 400 600 800

7. 5m高

6. 9m高

m海堤高度（ ）

10m 6cm每 互花 米 草消浪

Coastal zone robustness

• 114.6×7560×2.5= 2,165,940 RMB

Atmosphere regulation

• 植被每生产 1 g 干物质可以吸收固定CO21.63 g ，同时释放 1.19 g O2

– 固定二氧化碳的净价值为 1405 $/hm2/yr ～1852 $ /hm2/yr

– 释放氧气的经济价值是 2712 $/hm2/yr ～ 3608 $/hm2/yr

• 调节大气的总经济价值 Vreg 是 4117 ～5460 $/ hm2/yr 。

Direct and indirect market value

• Provisioning: 20,000 ～ 34,000 RMB /ha•yr• Heavy metal absorbance: 1660 ～ 14700 RMB/

ha•yr• Nutrient absorbance: 2,960 ～ 35,800 RMB/

ha•yr• Coastal zone robustness: 5,730 ～ 11,460

RMB/ha•yr• Atmosphere regulation: 33,760 ～ 44,760 RMB/

ha•yr• TEV: (2012): 2,899,058 RMB / ha (Inflation

rate ： 0.4, discount rate: 0.5 )

Challenges:

• If the value is true, do we need to protect the coastal wetland ecosystem?

• If the value is not true, what if missing?

TEV

Vuse Vnon-use

Direct use Indirect use Option value Bequest value Existence value

Non-market value

• Original non-market value ： CVM

• Related oefficient with the ecosystem scarcity: a

• Non-market value （ a=0.2 ）：aK= ￥ 579,811.6/ha

A. Kontogianni, 2012, Ecological Economics

Total value of eco-services

• TV=Market V (K)+Non-market V (aK) =2,899,058+579,811.6= 3,478,870 RMB/ha

V

p U

Is the problem sorted out?

TEV

Supply B

Supply A

Marginal Value

Flow of Services

$

Critical Threshold

Limburge et al. (Limburge et al. 2002)

Value of avoiding threshold

B. Catastrophic response function

A. Smooth response function

C. Tracking the approach to catastrophic threshold

Stress

Value of

service

K.E. Limburg et al. 2002

Valuing scarcities of the wetland eco-services – a conceptual model

V

u p

pp

ii du

pup

aKKVV

01

)/)(

(V ： TVK ： Market Vak ： Non-market Vp ： Critical Threshold

Conclusion

• The value of ecosystem’s scarcity is dynamic. It positively related to the scarcity of coastal wetland ecosystem.

• Valuing the scarcity of coastal wetland properly may assist the smart use of coastal resources. For instance, it may help to identify the threshould of different exploitation activities.

• Coastal wetland’s critical threshould (p) need to be further discussed.