Vegetation distribution of China and its responses to climate change

Ensheng Weng

Geographic features of China

Summer circulation

Tibetan Plateau plays a critical role

South-west monsoon

South-east monsoon

Westerly jet

Winter circulation

Tibetan Plateau plays a critical role

Westerly jet

Tibetan cold high

Siberia-Mongoliancold high

Climate of China

Climate of China

T (Jan.) T (Jul.)

Climate-Vegetation Relationships

• Climate determines vegetation distribution

• Precipitation and temperature are two key factors

from Whittaker, 1975

Vegetation of China

Wu, CY, 1980. Vegetation of China

Vegetation of China

Wu, CY, 1980. Vegetation of China

Tropical forest

Sub-Tropical forest

Temperate forest

Mixed forest

Taiga -

+

Vegetation of China

Wu, CY, 1980. Vegetation of China

Forest

Meadow

ste

ppe

Typ

ical

steppe

Desert

steppe

Desert

+-

Vegetation of China

Wu, CY, 1980. Vegetation of China

Conifer forests

Alpine meadows

Alpine steppes

Alpine deserts

Vegetation of China

Wu, CY, 1980. Vegetation of China

Conifer forests

Alpine meadows

Alpine steppes

Alpine deserts

Forest

Meadow

ste

ppe

Typ

ical

steppe

Desert

steppe

Desert

+-

Tropical forest

Sub-Tropical forest

Temperate forest

Mixed forest

Taiga -

+

How it response to climate change

Changes of Temperature in past 50 years

Northern area Central China

Changes of Precipitation in past 50 years

Scenarios at the end of 21st century

CO2 SRES-A2

CO2 SRES-B2

BIOME model

• Defined 14 plant functional types (PFTs);

• Assigned a climatic envelope for every PFT;

• porsposed a rule to regulate the co-exist of PFTs;

• Biomes (vegetation types) are the combinations of PFTs.

BIOME model

BIOME model

Calibration

Simulated map from original parameters

• the boundary between forests and steppes

• forests shift southwards

Calibration

Priestley-Taylor coefficient

Calibration

Temperature of January

Calibration

The same PFTs occur in the colder and dryer areas

The results from new parameters

Kappa=0.67

Response of vegetation distribution to climate change

CO2 SRES-A2 CO2 SRES-B2

Vulnerable areas

• Northern China• Southwestern China• Tibetan Plateau

Effects on Human beingDesertification Deforestation

Thank you!