temperature averages 17 °C in the year and 29 °C in the hottest month (July). Due
to the dense water network with numerous rivers and lakes, it is relatively humid
with large evaporation under long duration of sunshine, but it is extremely stuffy
when the temperature climbs to 40 °C. The coldest month (January) sees an average
temperature of around 4.5 °C and an average minimum temperature of 2 °C. The
annual frost-free period averages 237–261 days, while rainfall occurs in 130–
150 days per year, reaching about 1406.6 mm. The southeast wind dominates the
area, with an annual average wind speed of 2.17 m/s.
• Hydrological characteristics
On a city scale, lakes account for 27% of the city’s total area, mainly distributed in
riverside plain and low hilly farmland along the Yangtze River. In the administrative
area, waters cover about 3.5 km
2 . There are three small reservoirs with a total storage
capacity of 1.5768 million m
3 : Jiangyang Reservoir, Yuanmen Reservoir and Fenglei
Reservoir; and 135 ponds with a total storage capacity of 624,000 m
3 . The distribution and direction of surface water systems are as shown in Fig. 5.1.
(c) Soil and vegetation
Soils in the area are mainly made up of limestone, quartz diorite porphyry,
yellow-sand shale, purple-sand shale and Quaternary red clay parent rock. Plant
resources are abundant. Among them, arbors include cedar, masson pine, oak and
maple; shrubs include Loropetalum chinense var. rubrum, Buxus sempervirens L,
hybrida vicary privet, and French holly; grass includes Cymbopogon citratus,
Brassica campestris, Ipomoea pescaprae, Polygonum lapathifolium, Artemisia
argyi; aquatic plants include lotus root, water chestnut, duckweed, calamus, algae
(black algae), and water lotus.
(d) Mineral resources
Mineral resources are rich in the area. There are 11 kinds of proven mineral
resources, including gold, iron ore, coal, lead-zinc, pyrite, dolomite, granite, gypsum, clay and celestite.
(e) Groundwater utilization
Groundwater resources in the city amount to 125 million m
3 /year, of which 78% is
karst water. However,the groundwater resources are unevenly distributed,as more
than 70% of the groundwater resources exist in central and southern areas which
industries are underdeveloped. According to the investigation, before the tap water
is accessible, wells have been drilled without reaching the bedrock in each
household to extract the Quaternary pore water for domestic use. In mountainous
areas with large water depths, artificial groundwater extraction is difficult and
residents use springs as a source of water. Well water is used for cleaning after
residents have access to tap water for drinking.
94
5 Application Cases
to the dense water network with numerous rivers and lakes, it is relatively humid
with large evaporation under long duration of sunshine, but it is extremely stuffy
when the temperature climbs to 40 °C. The coldest month (January) sees an average
temperature of around 4.5 °C and an average minimum temperature of 2 °C. The
annual frost-free period averages 237–261 days, while rainfall occurs in 130–
150 days per year, reaching about 1406.6 mm. The southeast wind dominates the
area, with an annual average wind speed of 2.17 m/s.
• Hydrological characteristics
On a city scale, lakes account for 27% of the city’s total area, mainly distributed in
riverside plain and low hilly farmland along the Yangtze River. In the administrative
area, waters cover about 3.5 km
2 . There are three small reservoirs with a total storage
capacity of 1.5768 million m
3 : Jiangyang Reservoir, Yuanmen Reservoir and Fenglei
Reservoir; and 135 ponds with a total storage capacity of 624,000 m
3 . The distribution and direction of surface water systems are as shown in Fig. 5.1.
(c) Soil and vegetation
Soils in the area are mainly made up of limestone, quartz diorite porphyry,
yellow-sand shale, purple-sand shale and Quaternary red clay parent rock. Plant
resources are abundant. Among them, arbors include cedar, masson pine, oak and
maple; shrubs include Loropetalum chinense var. rubrum, Buxus sempervirens L,
hybrida vicary privet, and French holly; grass includes Cymbopogon citratus,
Brassica campestris, Ipomoea pescaprae, Polygonum lapathifolium, Artemisia
argyi; aquatic plants include lotus root, water chestnut, duckweed, calamus, algae
(black algae), and water lotus.
(d) Mineral resources
Mineral resources are rich in the area. There are 11 kinds of proven mineral
resources, including gold, iron ore, coal, lead-zinc, pyrite, dolomite, granite, gypsum, clay and celestite.
(e) Groundwater utilization
Groundwater resources in the city amount to 125 million m
3 /year, of which 78% is
karst water. However,the groundwater resources are unevenly distributed,as more
than 70% of the groundwater resources exist in central and southern areas which
industries are underdeveloped. According to the investigation, before the tap water
is accessible, wells have been drilled without reaching the bedrock in each
household to extract the Quaternary pore water for domestic use. In mountainous
areas with large water depths, artificial groundwater extraction is difficult and
residents use springs as a source of water. Well water is used for cleaning after
residents have access to tap water for drinking.
94
5 Application Cases