China's giant sinkholes are a tourist hit - but ancient forests inside are at risk

In the stunning Guangxi Province of China, sinkholes have become a fascinating attraction for tourists. These enormous holes in the ground are not just empty spaces; they are filled with ancient forests, unique plants, and diverse animals. When visitors peer into these sinkholes, they can see the tops of tall trees and hear the sounds of cicadas and birds echoing off the cliffs. For centuries, these 'heavenly pits,' known as 'tiankeng' in Mandarin, remained unexplored due to local fears of demons and ghosts that were believed to inhabit the mist rising from the depths. However, with the advent of drones and the courage of a few explorers, these hidden treasures are now being revealed to the world. Remarkably, China is home to two-thirds of the world's more than 300 sinkholes, with Guangxi boasting the highest concentration. The most significant discovery in recent years was made two years ago, when an ancient forest was found within a sinkhole, featuring trees that soar as high as 40 meters. These natural cavities serve as time capsules, preserving delicate ecosystems for centuries. However, the increasing influx of tourists and developers raises concerns about the potential loss of these rare environments. Rui and Michael, a couple eager for adventure, are preparing to explore one of these sinkholes. Rui, who is 25, expresses her excitement, saying, 'I’ve never done this kind of thing before. It’s very cool. It will be the first time but not the last time. ' They are about to embark on their journey with the guidance of Fei Ge, a seasoned explorer and tour guide. Fei, who grew up in a nearby village, recalls the warnings he received as a child to stay away from the sinkholes due to the frightening tales of spirits. Yet, his curiosity ultimately led him to explore these mysterious places. It was only when he invited scientists to study the sinkholes that he realized their true significance. The experts were amazed by the unique species they discovered, some of which had never been seen before. The sinkholes are formed when underground rivers gradually erode the surrounding limestone rock, creating expansive caves that eventually collapse, resulting in a massive hole. To qualify as a sinkhole, the depth must be at least 100 meters, and some, like the one found in Guangxi in 2022, are even larger, reaching depths of 300 meters and widths of 150 meters. For scientists, these sinkholes offer a glimpse into the past, allowing them to study plants and animals that were once thought to be extinct. As Rui and Michael prepare to descend into the sinkhole, they are filled with anticipation. This adventure represents a much-needed escape after the long Covid lockdowns in China. The rise of this type of tourism is becoming increasingly popular, especially among young people seeking thrilling experiences. Videos showcasing the sinkholes have gone viral on social media, drawing even more visitors to the area. The tourism boom is also benefiting the local economy, particularly in Ping'e village, which is the closest settlement to the sinkholes. Once a struggling community, Ping'e is now experiencing positive changes thanks to the influx of tourists. However, there are growing concerns that the rush for tourism could overshadow the importance of scientific research. Just 50 kilometers from Ping'e, developers have constructed what they claim to be the highest viewing platform, allowing tourists to peer 500 meters down into Dashiwei, the second-deepest sinkhole in the world. Dr. Lina Shen, a leading sinkhole researcher, emphasizes the need for better protection of these habitats, stating, 'Sinkholes are paradises for many rare and endangered plant species. We are continuing to make new discoveries. ' By studying these sinkholes, scientists hope to gain insights into how the Earth has changed over thousands of years and to better understand the effects of climate change. To safeguard unique orchid varieties, at least one sinkhole in Guangxi has already been closed to tourists. Dr. Shen warns that overdevelopment could lead to significant damage, urging for a balance between tourism and conservation. 'Hot air balloons, drones for aerial photography, and appropriate pathways for observation from a distance could allow tourists to closely yet remotely view sinkholes, while disturbing as few organisms as possible,' she suggests. Brother Fei shares this sentiment, insisting that there are clear rules in place to protect the sinkholes and their ecosystems. He takes pride in being a guide, helping others discover the wonders of these natural formations. As Rui and Michael venture deeper into the cave, they are reminded of the importance of preserving nature while enjoying its beauty. They are excited to explore the lush forest within the sinkhole, and Brother Fei encourages them to return after the rains to witness the breathtaking waterfalls cascading down the cliffs. This adventure is not just about thrill-seeking; it is also about appreciating and protecting the incredible natural world around us.