I received my advanced diving certification three decades ago and logged my last major dive sometime in early 2000, so there was some hesitation from the lack of practice when I was offered an opportunity to explore the Lijiang River underwater in Guilin as part of my latest assignment.

But when diving instructor Tang Junwen, who was leading our three-man team to help record the biodiversity of this iconic waterway, said I was probably the first foreigner to look at the Lijiang in this way, I knew I was right to take the plunge.

It was a warm, sunny afternoon. The calm waters of the river reflected the dense vegetation lining its shores. This was a quiet inlet, shielded from the tourist vessels and local fishing rafts that plied one of the top attractions of the tourism-centered city in South China's Guangxi Zhuang autonomous region.

Air tank, check. Regulator, buoyancy compensator, mask, fins and other basic scuba gear, check.

As I followed the team and descended steadily into the river, its warm waters slowly enveloped me. I tried to stabilize my breathing, with the bubbles exhaled via my regulator the only sounds I heard. I began to remember the sublime feeling of scuba diving.

I also knew enough to stay close to Tang and Jiang Peng, who was my other diving teammate. With our torchlights and Tang's local knowledge and experience, we spotted a fascinating array of aquatic life. From catfish and carp to loach and perch, the healthy state of the river was plain for all of us to see.

Tang later said biodiversity in the Lijiang River is obviously richer — it would have been unusual to record so many sightings of such a wide variety of fish just a decade ago.

Still, work to protect the river and its flora and fauna must continue in line with sustainable development. As part of ongoing environmental efforts, Tang leads groups of volunteers to pick up whatever trash they find on their dives.

During my own 50-minute dive, which took me up to 10.7 meters deep, I helped collect two porcelain shards, a plastic bottle, the broken handle of a fishing reel and a plastic bag of unidentifiable contents, all lodged in the sand or rock crevices.

Not bad for my first underwater experience of the Lijiang River.