Regenerating green color on the rocky mountains of Ha Long Bay

Ha Long Bay is considered by scientists to have high biodiversity with typical ecosystems of tropical seas and diverse species composition and genetic resources. After the devastation of Typhoon Yagi, the most visible feature here is the lush green vegetation on the islands with many trees uprooted, broken, crushed, only bare branches remaining, turning brown and withered covering most of the rocky mountains, posing the problem of regenerating and restoring the green color of Ha Long Bay...

The rocky mountains on Ha Long Bay were once covered in green with a variety of plant species.

According to information from the Ha Long Bay Management Board, up to now, scientists have counted about 3,000 species of animals and plants living on the unique ecosystems of the limestone archipelago here.

Among these, there are 830 terrestrial plant species, 278 phytoplankton species, 141 zooplankton species, 110 coral species, 156 marine fish species, 71 bird species, 53 mammal species... In particular, there are 15 endemic plant species, 102 species (including 21 plant species, 81 animal species) recorded as rare and endangered in the Vietnam Red Book in 2007.

The ecosystems in the Bay are also very diverse, from ecosystems of vegetation on islands, pine - ang, caves, hard bottom tidal zones, soft bottom, sandy tidal flats, mangrove forests to ecosystems of regularly flooded coastal areas and coral reefs. In particular, the ecosystem of vegetation on islands is the habitat and development of 830 plant species, many of which are endemic, rare, and endangered, listed in the Vietnam Red Book. The pine - ang ecosystem is a typical and unique ecosystem of the sea area with limestone islands such as Ha Long Bay - Bai Tu Long - Cat Ba. The biological community in the pine - ang in Ha Long Bay is quite diverse, so far over 72 species of animals and plants have been discovered living in the ang, including 21 species of seaweed, 37 species of mollusks, 8 species of crustaceans, 6 species of echinoderms and some species of coral.

The cotton tree is not only endemic to Vietnam but also blooms, resulting in beautiful landscapes for the heritage of Ha Long Bay.

Or like cave ecosystem is also a special ecosystem of the limestone sea of ​​Ha Long Bay. Because the living environment in caves is often completely different from the outside, the structure of biological communities is much poorer, however, there are still 2 species of fish and 6 species of crustaceans living in the water pools in caves that are recorded as endemic species of Ha Long Bay.

The coral reef ecosystem in Ha Long Bay is also quite unique, mainly composed of hard corals. According to a 2015 survey, there are 110 species of coral in Ha Long Bay, most concentrated in the areas of Cong Do, Tra San, Hang Trai, Dau Be with a coverage of 30-45%. Thanks to a relatively stable environment, with many caves to shelter and avoid enemies, Ha Long Bay coral reefs are home to many different species of organisms. Among them, there are many species that are threatened with extinction, rare and listed in the Vietnam Red List 2007...

Coral on Ha Long Bay. Photo provided by the unit.

Biodiversity value is one of the unique values ​​of Ha Long Bay in addition to aesthetic values, geological and geomorphological values ​​and cultural and historical values. After Typhoon Yagi , the change in the water environment here due to heavy rain, the accumulation of materials falling into the bay from coastal areas as well as the impact of storm winds causing falls and affecting the vegetation on the rocky mountains is quite clearly seen. Therefore, recently, in order to have an accurate assessment of the impacts on the vegetation here, Ha Long Bay Management Board invited experts from the Institute of Ecology - Biological Resources (Vietnam Academy of Science and Technology) to survey and evaluate the current status of Ha Long Bay after Typhoon Yagi and advise on solutions to preserve and promote the values ​​of Ha Long Bay sustainably.

A team of experts and staff surveyed the vegetation affected by Typhoon Yagi in Ha Long Bay. Photo provided by the unit.

The survey was conducted in a number of key areas. Accordingly, the phenomenon of tree falling, broken branches and leaf shedding has more or less different depending on the impact of wind.

For example, in the rocky mountains of Thien Cung - Dau Go cave or Hang So - Ba Hang, 100% of the trees were affected, of which 70% were able to recover, 30% were unable to recover due to uprooting and falling. At Vung Vieng, about 70-80% of the trees lost their leaves and were broken.

In areas such as Sung Sot Cave, Ti Top Cave, Hang Co Cave, Me Cung Cave, Soi Sim, many trees have broken tops and branches, a small number are uprooted, and have a high recovery potential. Ha Long palm trees in the Ti Top Cave area are still growing under the canopy. In the Tien Ong - Cua Van area, the trees are almost unaffected, 15 Ha Long palm trees here are growing normally... After the storm, many trees have now sprouted green shoots and young leaves, but it will take 4-6 months for recovery to be evident.

The assessment shows that the decline in vegetation cover on limestone mountains will negatively affect a number of endemic plants and plants with landscape value in Ha Long Bay, such as: Ha Long Cycads, Ha Long Palms, Slipper Orchids, Cottonwoods... At the same time, it will also negatively impact the habitat of wild animals, directly affecting the habitat of a number of birds, reptiles and the regular food source of the golden monkeys Macaca mulatta living on the islands in the heritage area. These pose the problem of finding suitable and effective solutions and plans to overcome and soon restore the green color on the rocky mountains of Ha Long Bay.

In addition, the vegetation on the islands with many dry leaves and tree trunks is also at high risk of forest fires, especially in the upcoming dry season. Therefore, experts recommend that in some areas with high risk of fire such as Dau Go - Thien Cung cave area, Sung Sot cave, Ti Top, it is necessary to have measures to prevent forest fires, install fire prohibition signs, fire prevention signs, especially at tourist attractions...