17.2 Environmental Flow Research and Management in China
363
in the basin has risen and the area of the groundwater has increased. In the Heihe
River, following subsequent environmental releases, the end-tail of Dongjuyan Lake
has appeared and increased the lake’s surface area.
17.3 Environmental Flow Assessment and Water Resources
Planning in the Jiaojiang River, Zhejiang Province
17.3.1 Brief Introduction
Taizhou has 21 rivers (including tributaries), with each covering a basin area of over
100 km
2 . The most significant of these is the Jiaojiang River, which is the third-largest
river basin in Zhejiang Province. With a total length of 208.2 km and a catchment
area of 6,750 km
2 , the Jiaojiang River covers 70% of Taizhou’s land area.
The section from the headwaters of Jiaojiang River to Sanjiang Village (in Linhai)
is called the Yong’an Creek. The mid-stream section, from Sanjiang Village to
Sanjiangkou, is called the Ling River. The lower reaches, from Sanjiangkou to
Niutoujing, are referred to as the Jiaojiang River. The estuarine section of the Jiaojiang River runs from Niutoujing to Songpuzha, where it reaches Taizhou Bay and
the East China Sea. The major tributaries in the Jiaojiang River system are Shifeng
Creek (with a length of 122.1 km and basin area of 1,609 km
2 ) and the Yongning
River (with a length of 77.2 km and basin area of 890 km
2 ).
Taizhou’s landform is high in the west and low in the east. On the east coast
are the Wenhuang, Jiaojiangbei, and Datian plains. Sanmen Bay is located in the
north, Taizhou Bay in the middle, Aiwan Bay in the southeast, and Leqing Bay in the
southwest. Taizhou Prefecture includes 687 islands near the east coast. The mainland
coastline is 745 km long, while the total coastline (including islands) is 1,660 km.
The main types of landform are hills and mountains, which cover 73% of Taizhou’s
land area. The plains cover 22.4%, and the inland water area accounts for 4.6%.
Taizhou’s climate is subtropical and monsoonal. The division of seasons is clear.
The average temperature is between 16.6 and 17.3 °C, increasing from north to south.
The extreme temperatures range between lows of −5.4 to −9.9 °C and highs of 33.8
to 41.7 °C.
Taizhou receives regular and relatively high wet season rainfall due to monsoonal
and typhoon influences. Average annual precipitation across Taizhou is 1,632 mm,
and average annual runoff ranges between 600 and 1,200 mm. Floods are common
in the wet season. However, a distinct dry season exists during winter. Periods of
drought are of relatively short duration.
The Jiaojiang River Basin lies within the evergreen broad-leaved forest vegetation
region of China. The natural vegetation in the basin consists of subtropical evergreen
broad-leaved forests and needle-leaved evergreen forests. Typical central subtropical evergreen broad-leaved forests are distributed in areas at altitudes from 650 to
1,250 m. Mason pine forests are distributed in hilly regions below 800 m. Chinese fir
363
in the basin has risen and the area of the groundwater has increased. In the Heihe
River, following subsequent environmental releases, the end-tail of Dongjuyan Lake
has appeared and increased the lake’s surface area.
17.3 Environmental Flow Assessment and Water Resources
Planning in the Jiaojiang River, Zhejiang Province
17.3.1 Brief Introduction
Taizhou has 21 rivers (including tributaries), with each covering a basin area of over
100 km
2 . The most significant of these is the Jiaojiang River, which is the third-largest
river basin in Zhejiang Province. With a total length of 208.2 km and a catchment
area of 6,750 km
2 , the Jiaojiang River covers 70% of Taizhou’s land area.
The section from the headwaters of Jiaojiang River to Sanjiang Village (in Linhai)
is called the Yong’an Creek. The mid-stream section, from Sanjiang Village to
Sanjiangkou, is called the Ling River. The lower reaches, from Sanjiangkou to
Niutoujing, are referred to as the Jiaojiang River. The estuarine section of the Jiaojiang River runs from Niutoujing to Songpuzha, where it reaches Taizhou Bay and
the East China Sea. The major tributaries in the Jiaojiang River system are Shifeng
Creek (with a length of 122.1 km and basin area of 1,609 km
2 ) and the Yongning
River (with a length of 77.2 km and basin area of 890 km
2 ).
Taizhou’s landform is high in the west and low in the east. On the east coast
are the Wenhuang, Jiaojiangbei, and Datian plains. Sanmen Bay is located in the
north, Taizhou Bay in the middle, Aiwan Bay in the southeast, and Leqing Bay in the
southwest. Taizhou Prefecture includes 687 islands near the east coast. The mainland
coastline is 745 km long, while the total coastline (including islands) is 1,660 km.
The main types of landform are hills and mountains, which cover 73% of Taizhou’s
land area. The plains cover 22.4%, and the inland water area accounts for 4.6%.
Taizhou’s climate is subtropical and monsoonal. The division of seasons is clear.
The average temperature is between 16.6 and 17.3 °C, increasing from north to south.
The extreme temperatures range between lows of −5.4 to −9.9 °C and highs of 33.8
to 41.7 °C.
Taizhou receives regular and relatively high wet season rainfall due to monsoonal
and typhoon influences. Average annual precipitation across Taizhou is 1,632 mm,
and average annual runoff ranges between 600 and 1,200 mm. Floods are common
in the wet season. However, a distinct dry season exists during winter. Periods of
drought are of relatively short duration.
The Jiaojiang River Basin lies within the evergreen broad-leaved forest vegetation
region of China. The natural vegetation in the basin consists of subtropical evergreen
broad-leaved forests and needle-leaved evergreen forests. Typical central subtropical evergreen broad-leaved forests are distributed in areas at altitudes from 650 to
1,250 m. Mason pine forests are distributed in hilly regions below 800 m. Chinese fir