The earthquake that struck Sichuan Province on May 12, 2008 was China's most damaging earthquake since the 1976 Tangshan earthquake disaster. Sichuan, a province in western China, has been historically known as the "Land of Abundance" (Tian Fu Zhi Guo), as it is one of the major agricultural production bases of China.
The most immediate concerns after such a disaster are human casualties, injury, and property destruction. However, earthquakes and other natural disasters wreak substantial environmental damage, with consequences for human health and economy as well as biodiversity and resource availability. In China, the environmental destruction is just beginning to be estimated, though some impacts, such as ecosystem degradation and agricultural disturbance, may not be observed for months or years. In addition, rebuilding thousands of homes in a fragile region presents its own challenge to resource management and land protection.
Background
Though the epicenter of the earthquake in Wenchuan was in a mountainous area, approximately 603,000 people lived in the region most violently affected by the earthquake. In this area the shaking was estimated as Modified Mercalli Intensity X: Disastrous, meaning that most masonry and frame structures were destroyed with their foundations (see USGS Eastern Sichuan Earthquake map). The complex topography of the region adds to the difficulties of rescue and reconstruction.
Figure 1. Map of Earthquake Epicenter
Source: Wikimedia Commons
| Quick facts on the Wenchuan earthquake: | |
| Time | May,12, 2008 14:28 |
| Magnitude | 8.0 Ms(surface) |
| Dead | 69,185 |
| Injured | 374,171 |
| Missing | 18,467 |
Source: China Relief Net (Chinese). Numbers current as of June 24, 2008.
Though rescue missions are complete in China, earthquake recovery is far from over. According to the IUCN assessment of the 2005 earthquake in Pakistan, planning of relief and rehabilitation measures must differentiate among short-term (urgent, vital, life-saving), medium-term (temporary solutions, over the winter), and medium- to long-term (reconstruction/rehabilitation, measures for human well-being, environmental considerations) phases of earthquake relief. Looking ahead, there are many long-term environmental impacts of the earthquake that will need to be addressed both by China and the international community.
Immediate Environmental Effects
Some of the environmental damages of the earthquake and subsequent landslides were immediately obvious, and are common environmental threats of earthquakes. In China, the greatest concerns are disposal of debris, ecosystem and habitat loss, water contamination, and destruction of arable land.
* Debris and waste
Proper disposal of all the debris from buildings that were destroyed presents a large environmental and health challenge. According to incomplete statistics given by the State Council Information Office, about 5,932,500 houses were seriously damaged and 5,461,900 houses collapsed; however, over 21 million other structures throughout Sichuan Province may have been affected as well. China's military has already disposed of nearly 8 million cubic meters of debris, enough to fill the primary Olympic stadium in Beijing almost 16 times. And cleanup has barely begun, as the government's priority has instead been providing temporary housing.
Eventually, the rubble is probably destined to be dumped into the fields and valleys of rural areas, though some may be recycled for rebuilding. However, some neighborhoods and croplands have also become dumping grounds for the detritus, causing residents to worry about health impacts.
In a medical emergency of this scale, another prominent environmental and health concern is disposal of medical waste. Not all medical waste has infectious potential, but that which does needs to be handled especially cautiously. On May 13th, the newly-established Ministry of Environmental Protection released Earthquake-safe Technical Guidelines for Disposal of Medical Waste (provisional) (Chinese), which laid out standards for storage, transportation, and safe disposal of medical waste. Among other guidelines, the Ministry has said that medical waste should be first disinfected and then burned or buried, and that infectious waste is first priority for disposal.
* Ecosystem and habitat loss
The earthquake was centered in the Minshan-Hengduan Mountains, a key area of biodiversity conservation that is ecologically very sensitive and rich in species: 12 national first-class protected animals and 24 state-level rare and endangered plants have habitats there.
In addition, Sichuan houses the primary reserves for China's endangered icon, the giant panda. China is the only country in which pandas live in the wild. Forty-nine panda reserves suffered damage in the quake, including the Wolong Nature Reserve, which was the site of the quake's epicenter. In all, it's estimated that 80 percent of panda habitat in Sichuan was damaged in the quake, though this measurement – and any panda casualties – have been difficult to verify because the area is still largely inaccessible.
Figure 2. Chinese Provinces with Greatest Area in Nature Reserves
Sichuan ranks sixth among China's 31 provinces in terms of protected area, a substantial part of which may have been damaged by the earthquake.
Source: EarthTrends, 2008, using data from China Statistics Yearbook 2007 (Chinese)
* Water
According to Jonathan Randall, a WWF Humanitarian Partnerships program officer, one of the biggest environmental issues in the immediate weeks after the earthquake is contaminated drinking water. Hazardous material spills from ruptured tanks and pipes of factories have the potential to leak into water supply. In addition, temporary water supply to some remote areas has been limited because of the difficulty of transportation.
In addition to environmental concerns, the sheer physical presence of water poses health concerns. Landslides filled in portions of rivers in Sichuan province, creating "quake lakes," huge pools of backed-up water. These quake lakes are a lingering threat to residents, potentially endangering the lives of millions of people if the water builds up and then barriers break. Tangjiashan quake lake is the largest quake lake, and has been urgently dredged to lessen the danger.
* Land and agriculture
Sichuan is a major agricultural province in China, with the highest rice yield in the nation. Agricultural products occupy an important position in the region's economy, but the agricultural system has been severely damaged and is still threatened.
The earthquake not only caused crop loss, but rock- and mudslides have caused an estimated 400,000 hectares of arable land to be permanently lost, although detailed investigation is still underway. The irrigation system has also been damaged and will need a long time to repair. In addition, agricultural land is vulnerable as reconstruction begins, since this land may be taken over by temporary settlements or repurposed for rebuilding towns.
China's rice harvest, beginning in a few months, will likely show the effects of Sichuan's depleted agricultural system, though it may be years before the earthquake's long-term consequences on agriculture are visible.
Figure 3. Highest Grain-Producing Provinces in China
Grain production in Sichuan is among the highest in the nation; an estimated 8% of arable land in Sichuan has been destroyed by the earthquake and subsequent landslides.
Source: EarthTrends, 2008, using data from China Statistics Yearbook 2007 (Chinese)
Environmental Considerations in Reconstruction
The effects of the earthquake didn't end when the aftershocks ended. Rebuilding destroyed cities from the ground up will require a huge amount of resources for years to come. China has been acclaimed by the international community for their rescue efforts. But the long process of reconstruction, now underway, will require prolonged funding and, if it is to be accomplished with minimal environmental impact, a strong intentionality toward sustainable development.
* Rebuilding structures
Some of the hardest hit areas, like Beichuan County, were razed to the ground. It was estimated that 99% of the houses in Qingchuan County will need to be reconstructed. In addition to buildings, many highways, railways, bridges, electricity and communications networks, water reservoirs and other infrastructure elements have been seriously damaged. These infrastructure damages not only add to the financial and environmental cost of the quake, but complicate the execution of other reconstruction efforts.
The mountain ecosystem also presents challenges for rebuilding. Land suitable for building is limited, resource availability is comparatively low, and the terrain makes it challenging for supplies to be transported in and debris moved out. The huge reconstruction demand will increase environmental pressures in this area.
On June 8th, Premier Wen Jiabao signed a regulation on reconstruction (Regulation on Recovery and Reconstruction of the Wenchuan Earthquake (Chinese)) which established "combin[ing] the protection of the ecological environment with economic and social development" as a guiding principle in reconstruction.
* Transitional settlements
The huge number of houses collapsed in the quake resulted in millions of people homeless. Though many have been living in tents since the disaster, the government has released guidelines for the construction of more permanent transitional settlements (Earthquake-stricken Area Transitional Settlements: Technical Guidelines for Environmental Protection (provisional) (Chinese)). Such settlements necessitate their own environmental considerations, including where they will be constructed and how residents will obtain food, water, and fuel.
Since such transitional settlements are just now being constructed, it remains to be seen what their net environmental impact will be over the months or years of their existence. The June 8th regulation emphasized that settlements should occupy farmland as little as possible, avoid pollution of drinking water sources, and protect vulnerable ecological areas.
A New Model for the Future
As reconstruction is carried out, China's relief organizations, researchers, and government officials will be studying how to improve disaster prevention and response in the future. In addition, the process will create a better understanding of rebuilding around the altered geography of disaster-stricken areas, disaster's psychological effects, and the feasibility of an integrated ecological, economic, and cultural solution to natural disaster.
As C. S. Kiang, Chairman of Peking University Environment Fund, proposed, the earthquake may actually promote a change in China's model of development, bringing about a new "ecological civilization" after the tragic disaster. Sichuan faces unprecedented challenges in developing a possible "Wenchuan Model," but the result could be an improved means for living with disasters.
Related Links:
U.S. Geological Survey: Sichuan Earthquake
EarthTrends:
China & Taiwan Country Profiles
