Six years ago, I took a two-week trip to Yunnan province, which is famous for its mild weather, abundant rainfall and tropical vegetation. I toured such popular tourist destinations as Lijiang and Dali and visited Cangyuan county in the southwestern part of the province, bordering Myanmar.

Cangyuan county officials complained about the area's poverty and backwardness, but I was impressed with the lush vegetation that covered much of the mountainous county.

I was even more amazed when I toured the Nangunhe area, a national nature preserve under the county's jurisdiction. Within sight of the nature preserve's offices were pristine rainforests which were home to a large number of wild animals, including elephants.

These forests are blessed with abundant rainfall, especially during the monsoon season. Heavy rains had just washed over the county when I arrived, and the roads to some remote villages were still blocked.

Six years ago, I could never have imagined that this area would suffer from drought. Now, however, a prolonged shortage of rain has crippled Yunnan as well as Guizhou, Guangxi, Sichuan and Chongqing in the southwestern part of China.

According to local meteorologists, Cangyuan got approximately 100 mm of rain between October and February, about a third of what it normally gets in a year.

Within the Nangunhe nature preserve, the water levels of the three main rivers have fallen by 30 cm, while three smaller streams have dried up altogether. Of 53 ponds where wild animals are accustomed to finding water, six have dried up.

It rained for 12 hours on parts of Yunnan, including Cangyuan county, last week, but that was nowhere near enough to restore the rivers or replenish the water table. Some 8 million people in the province are still having a hard time getting enough water to drink.

There has been a lot of speculation over the cause of the current drought.

When I was in Cangyuan, some local officials told me they were worried about plans to supplant a variety of local trees and shrubs with eucalyptus - trees that grow fast and are a good source of pulp for paper-making. One official said he feared the eucalyptus would lower the water table and disrupt the local ecology.

However, I think the findings of local archivists offer more insight into the current situation. Despite its reputation for lush vegetation and abundant rainfall, Yunnan has not always been so blessed.

According to local records, Yunnan suffered severe drought in 76 of the 691 years between 1300 and 1991. Since the founding of New China in 1949, Yunnan has battled drought in eight of 60 years.

Each time, the province mobilized residents to dig deep wells to secure drinking water and build new irrigation systems.

Local people have devised a lot of ingenious ways to channel and conserve water. Recent TV reports show how each family has maintained a cistern on their land to preserve rainwater and store water from nearby streams.

Some villagers have also devised an alternative to expensive drip irrigation, using plastic bags or pipes with small holes to keep their crops and fruit trees moist.

Yunnan and its neighbors will heave a sigh of relief once the monsoon season finally arrives. But history tells us not to take the blessing of rainfall for granted. We must continue to find ways to preserve what nature has to offer instead of squandering it.

E-mail: lixing@chinadaily.com.cn