Site sustainable development opportunities and constraints summary

Figure 40 (Google image, 2021): Sand and dust storm in Jiuquan

7. Vegetation.

Jiuquan’s economy is based on agriculture, and the dominant land use in the rural

area is for cultivation. Subsequently, the primary vegetation type on the site is the

crop. Besides, Pinaceae, Salicaceae, Tamaricaceae and Polygonaceae are the

commonly seen tree types, and sporadic signs of forests or woods can be found in

the suburban rural area of Jiuquan (Pan, 2007).

Site sustainable development opportunities and constraints summary:

Topics Opportunity Reason Constrain Reason

located in a cold desert climate zone

Prevailing

wind

34 The goals and measures of lowcarbon development are straightforward and clear. The site has a particular climate variation in different seasons. Climate changes dramatically during season exchanges.

There is a potential to use wind power to generate renewable energy on-site (Zhu, et al., 2009) and use the natural wind to ventilate the houses passively. Jiuquan constantly has significant wind resources. There is a risk of losing heat through the building surface caused by extreme weather conditions in winter. Sand-dust storms. Maximum air temperature can be up to 30 ℃. minimum air temperature can be lower than -20℃.

Airtightness design is challenging. Mechanical ventilation should be required as well to maintain the interior air quality.

Low precipitation and relative humidity

Abundant water resources

Solar energy

Vegetation

35 Relatively lower requirement on rainproof and dampproof. Low risk of rusting and decaying on building fabrics and structures.

There is a potential of using hydropower in Jiuquan. Rural water supply does not necessarily need to rely on the city grid.

Generating solar power through solar photovoltaics (solar P.V.). Pre-heating water through a solar thermal system.

The site has open flexibility in arranging designated landscapes and vegetations. Dry and temperate air in Jiuquan.

Theoretical hydropower power reserve: 18130 Mw (Wang, 2011). Abundant groundwater resources.

Gansu is one of the leading provinces with the highest solar energy reserve in China (Zhu, et al., 2010).

Rural areas in Jiuquan are mostly flatlands without too many restrictions on planting caused by topography. Dry and dusty air may also hurt people’s living comfort level.

Hydropower stations may disturb the balance of the site’s ecoenvironment. It is unsafe to drink untreated underground water directly.

It is challenging to promote solar power technologies in the rural areas of China (Li, 2007).

There are limited chances of natural summer shading and winter wind barriers provided by existing vegetation. The suggested air humidity for better living comfort is between 40% to 60% (Heywood, 2015), whereas some months in Jiuquan have a relative humidity lower than 40%. Air purification devices may be needed for filtering indoor floating dust. People’s Government of Gansu Province (2018) had to shut down many substandard hydropower stations in Qilian Mountain National Nature Reserve because of the negative impact they brought to the rivers’ ecological systems. The high alkalinity of water resources in Jiuquan (Yu and Zhang, 2017). The spreading is restricted by the underdeveloped onsite grid infrastructures, unfriendly starting prices, and the poor acceptability of solar power to low-income farmers (Wang, 2012). The signs of large-scale forests or woods can be hardly found on the site (Pan, 2007).

Basic public utilities On-site renewable energy supply might be sufficient to cover the residents’ daily demands on power utilisation, even though most of the rural areas of Jiuquan have already been covered in the grid. Biomass power would also be a feasible option on the site. The Government of Jiuquan (2016) (2021) has made announcements regarding securing the power and water supply in the rural area of Jiuquan and their upgrade plans. Currently, there is almost no grid gas supplied on the site. Some villages do not have proper sewage treatment systems. Thus, numerous residents there still use pit privies as toilets. The potential of bringing the gas grid to the site exists, but it is not cost-effective considering the limited funding and the complex construction process (Li, 2018). It is difficult to link the rural areas’ sewer lines with the city grid, whereas the government plans to build small on-site sewage treatment facilities. (Zhang, 2018).

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