The Adverse Effects of the Changing Climate on the Indian Forests, Especially the Eastern Himalayas

It was some 50 million years ago that the Indian plate came floating on the Tethys Sea, like a Noah’s Ark, carrying a cargo of flora and fauna, ancient rivers, rift valleys, ancient mountains, and the plateau. This landmass collided with the stable Asian Plate and a mountain range emerged along the collision line – the Himalayas, the world’s loftiest and youngest range of mountains. The flora and fauna, initially carried by the Indian plate, now forms a diverse range of vegetation on the Himalayan mountain ranges, especially the Eastern Himalayas (EH). The EH touch three countries: India, Nepal and Bhutan. The low elevation areas and the foothills of the EH in northern India, Nepal and Bhutan, are covered by a thick layer of broadleaf and conifer forests. The forest ecosystem of this region can be classified into four broad categories: Eastern Himalayan broadleaf forests, Eastern Himalayan sub-alpine conifer forests, Northern Triangle temperate forests, and Northeastern Himalayan sub-alpine conifer forests. These mid-elevation forests are distinctive because they are a sanctuary for an assorted variety of wildlife and plants. 

However, the cause for concern is that these rich Eastern Himalayan forests are being adversely affected by the climatic changes due to global warming. The climatic changes may bring about an increased aggression of pests, abundance of obtrusive foliage and irreversibly affect the forest types. So far the countries concerned (India, Nepal and Bhutan) were concentrating on alleviation policies but under the present circumstances, departure from the mitigation strategies is necessary. The need is to focus on transformation strategies. The transformation (adaptation) techniques may include arresting of forest fires and implementation of dedicated corridors with adequate protection, which in turn, will improve and prolong the life of this global eco-region.

The Eastern Himalayan forest regions in India

The Eastern Himalayan broadleaf forests are found at an altitude of 2,000 to 3,000 metres in Arunachal Pradesh and Nagaland, which plays an important role in conserving the ecosystem of this particularly eco-sensitive zone. These forests are the sanctuary of several migratory birds and other forms of wildlife. Conservation of this natural wildlife is essential since it is directly related to the water basins frequenting the steep mountain slope. These forests receive the highest rainfall (2,000 mm) during the monsoon season from May to September. Factors like temperature, high rainfall and the land contour (topography) make these forests extremely rich in vegetation life. This forest ecosystem comprises two broad groups, the evergreen oak forests and the deciduous forest, dominated by species like Juglans regia and Alnus nepalensis.

Impending danger faced by the Indian forests, especially Himalayan forests

As prophesied by a government report, the climatic changes are going to have an adverse effect on the forests of India, especially the Upper Himalayan forests, which are already plagued by human interference. The findings of India’s second National Communication to the United Nations Framework on Climate Change, as published by Environment Minister Jayanthi Natharajan, appears to be quite grim. The report has been generated on a thoroughly scientific basis. First, the entire country was demarcated into sectors (grids), using a ‘High Resolution Mapping Technique’.  The said mapping technique broke up the total area of the country into more than 165,000 sectors, of which 35,889 grids were specified as forest areas, mentioning the types and densities of the forest areas covered by such grid. The entire grid map had a digitized version which specifically indicated the forested areas of our country, underlining the forest area and the location. This digitized grid map accompanied the report. The risk evaluation projected that forested areas all over the country are on the line of damage due to climatic changes, and that 45% of the forest sectors will be affected adversely due to such changes. As the report pointed out, the vulnerability of the forest areas seems to be maximum in the Upper Himalayas and some other areas of the country. As stated by the report, “However, their concentration is higher in the Upper Himalayan stretches, parts of central India, northern Western Ghats and Eastern Ghats”. The adverse effect of the changing climate is already apparent from the ‘Browning’ of the forests of the Eastern Himalayas, accompanied by a marked decay of the foliage and the trees.

The report further confirmed the enhanced vulnerability of the Upper Himalayas: “Most of the mountainous forests–sub-alpine and alpine, the Himalayan dry temperature forests and the Himalayan moist temperature forests–are susceptible to the adverse effects of climate change”. Where the Upper Himalayas face the maximum risk, the northeastern forests, southern Western Ghats, and the eastern Indian forests are far less susceptible to climatic changes. The report also threaded together apparently isolated national issues like economic growth, geography and overall developmental necessities and purported the best approach India can possibly take to protect its precious forest reserves. The Environment Minister Jayanthi Natharajan pledged to uphold and defend the forest protection issue as a part of the global commitment towards environmental changes.


As per a WWF survey, 12 to 15 million hectares of forests disappear every year from the face of the earth. This rate is equivalent to the disappearance of 36 football fields per minute. India was once covered by dense forests, which were habitats of a variety of wildlife. But the development in the other sectors of the country, and the emergence of India as a rapidly developing economy, has led to deforestation on a massive scale. It is only recently that our country has opened its eyes to environmental issues. Already the forests of India are beleaguered by human encroachments. It is to be mentioned here that India is one of the largest consumers of fuel wood. Now the climatic changes have added to the challenges faced by the forests. We have ignored the fragility of the eco–sensitive Himalayas and plundered the mountains indiscriminately, the consequence of which was the Uttarakhand disaster. We must accept the important role that the Himalayan forests play in maintaining the ecological balance of the Himalayan region. We should immediately stop unwanted human impact in the said regions and protect the Himalayan as well as other endangered forests from the adverse effects of the changing climate.