New study finds increased abundance and diversity in areas that were selectively logged 40 years ago
Forest canopy, termed the final biological frontier, house vascular epiphytes, which form a rich assemblage of plants within the forest canopy. Described as plants that grow on other plants and are devoid of any connection to the soil, epiphytes are said to maintain diverse taxa in addition to fulfilling important ecological functions.
Vascular epiphytes are particularly sensitive to microclimate and microhabitat disturbances within canopies, particularly from changes such as logging. Selective felling of trees in the Western Ghats has a profound impact on the epiphyte community and continues to impact 40 years after logging activities have stopped, a new study recently published in the journal Frontiers for Forests and Global Change has found.
Although epiphytes are well studied in India, parts of Central and South America and parts of Europe, this was the first assessment, said lead author KS Seshadri, a DST-inspired faculty at the Center for Ecological Sciences, Indian Institute of Science. Fellow said. ,
“We found over 2,000 individuals of 20 epiphyte species growing on 177 out of 200 trees. We compared epiphyte species diversity and abundance between an area where trees were selectively logged 40 years ago and another area that was unlogged. We saw an increase in abundance and diversity in the logged forest compared to the unlogged one,” he said.
When the researchers compared the splitting of host trees among epiphytes, a greater number of them were growing selectively in logs than in unlogs on the same tree.
“This suggests an overcrowding effect, either due to suitable conditions such as light availability or lack of substrates due to logging,” he explained, one reason why so few studies exist is because they are difficult to be observed from the ground. .
Other authors of the study, ‘Permanent Effects of Historical Selective Logging on a Convective Epiphyte Assembly in the Forest Canopy of the Western Ghats, India’ are R Ganesan and Soubadra M., from the Ashoka Trust for Research in Ecology and the Environment. Davy is. ,
Researchers used a ‘single-rope technique’ to gain access to canopy and study epiphyte ecology in remote forests of Kalakad Mundanthurai Tiger Reserve in Tamil Nadu. Mr Seshadri said he had to climb trees to study the epiphytes as they would not be visible from the ground.
According to the study, vascular epiphytes are diverse, comprising more than 31,100 species distributed globally and accounting for about 10% of all extant plants. According to Dr. Seshadri, epiphytic plants are structurally dependent on the host tree.
“These plant communities on the branches act as a microcosm for other forms of biodiversity, such as insects, either by providing food resources or by serving as refuge in harsh climates in the canopy. Many epiphytic orchids support bees and insects. myriad diversity such as pollinators. In addition to supporting other forms of biodiversity, they are an important component of forests that store carbon by absorbing CO2. Because they are separated from the ground, they remain intact throughout their lives. complete the life cycle in the canopy and make up a large proportion of nutrients in the form of canopy soil-organic matter, which consists of dead and decaying litter, roughly equivalent to that from trees,” he explained.
Climate change has been termed as a major emerging threat. Changes such as greater warming or more, erratic rainfall will put pressure on the epiphyte community because they are on average 40 feet above the ground, and are moving upward in contrast to species distributions. As it gets colder, canopy epiphytes, have nowhere else to go.
“The other major threat to epiphytes, especially orchids, is the illegal harvesting of plants for trade. All kinds of exotic orchids to be sold only require one visit to a nursery. While many are cultivating, it is important to know exactly what they are doing.” There is no way of knowing whether a plant was harvested from the wild. Not all epiphytic orchids grow to a height of 40 feet, but are found growing vertically on a tree. People sometimes collect fallen epiphytes as well. which should belong to the forest and not to our homes,” Dr Seshadri said.
The researchers hope that their findings contribute to the knowledge of vascular epiphytes from South and Southeast Asia and set the stage for future research and conservation.