Why did Rhino Lake suddenly disappear?

There is a rhinoceros lake under Meiren Peak in Yangshuo, Guilin, covering an area of about 20 square kilometers. Rhino Lake is sweet and clear, and groups of fish and shrimp swim around it. However, 1987 On the night of September 30, the lake miraculously disappeared. Only one night, the bottom of the lake was seen, leaving fish and shrimp struggling in the mud pond. Where did the lake go? It turns out that Guilin is full of soluble rocks such as limestone, and karst landforms such as karst caves, karst caves, milk peaks, stone forests and underground rivers can be seen everywhere. There are some dissolved holes at the bottom of the rhinoceros lake, which are connected with the underground river, and the lake water keeps infiltrating into the underground river from the dissolved holes. When the rhinoceros lake area encounters heavy rain, the rain carries a large amount of sediment into the lake, causing sediment to deposit at the bottom of the lake, blocking the dissolved hole connecting the bottom of the lake with the underground river, and the lake will increase and rise. Later, with the continuous flow of lake water, the blocked dissolved holes were gradually dredged, and the lake water entered the underground river from the dissolved holes and gradually decreased. When the karst hole is expanding, the flowing water in the lake will accelerate into the underground river, thus making the lake disappear completely. This is why the lake disappeared on the night of September 30.