Nepal Earthquake: Need to Quantify Impact on  
Forest Ecosystem 

Forest ecosystems are affected by many kinds of disturbances which are 
recognized as natural and integral part of their development. However, when the 
normal range of variation due to a disturbance is exceeded, it could result in large-
scale destruction of forest ecosystem structure and its functioning. Geophysical 
disturbance such as earthquakes and volcanoes can be cited as examples of 
such disturbances. Although earthquakes commonly occur in tectonically active 
regions, large-magnitude earthquakes can have serious disturbance in forests over 
large areas. The extent of the damage is, however, determined by the distance 
from the epicenter of the earthquake.

Nepal is situated in a tectonically active region in South Asia. On 25th April 2015, 
Nepal experienced a major earthquake followed by numerous aftershocks. These 
events resulted in the loss of thousands of lives, severe-injuries and devastating 
damages to buildings and infrastructures. The districts in the central part of Nepal 
that were close to the epicenter were the hardest hit. The earthquake triggered 
landslides in many districts of Nepal. These landslides have not only damaged 
houses and farmlands but also impacted the forest areas on the mountain slopes. 
The impact of landslides include removal of surface vegetation, damage to trees 
during the movement of debris from higher-slopes to down-slopes as well as final 
deposition which either completely cover forested-areas or cause partial damage 
to forest stand. The landslide impacts have the potential to get worse during 
the monsoon season. The impacts on forest can also include physical impact to 
tree roots, shift in ground level due to soil liquefaction and even water table. 
Thus, in addition to immediate mortality, trees may suffer longer-term impact of 
disturbance in terms of wood quality, regeneration and stand structure. 

Another impact of the kind disaster on forests would be increased demand for 
timber for reconstruction of damaged buildings. Also, there is a likelihood of 
encroachment in forest areas as they often provide open-access land for people to 
build temporary shelters. Forest administration has to be vigilant of this possibility 
and should, therefore, adopt appropriate strategies to manage this possibility.

Landslides can influence forest biodiversity and services through their impact on 
forest structure, composition and function. Maintaining biological diversity and 

Banko Janakari 
A Journal of Forestry Information for Nepal



Banko Janakari, Vol. 25, No. 1

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other ecosystem services are significant in the context of Nepal where many people 
are dependent on forest resources. In order to build our scientific understanding 
of the impact of abiotic disturbance such as landslides, more information is 
required regarding the nature and extent of forest disturbance. Therefore, there 
is an immediate need to quantify earthquake-induced impact on forest resources 
in Nepal so as to plan and implement appropriate actions to mitigate damages as 
well as to support forest restoration in future. Recently, the Ministry of Forests 
and Soil Conservation, in coordination with the Ministry of Science, Technology 
and Environment has contributed to the preparation of environment and forestry 
component of the post-disaster need assessment. This exercise has provided 
important baseline information for identifying major issues, and direct and 
indirect impacts on environment and forests.  

With the development of remote sensing methods/algorithms as well as availability 
of high-resolution satellite imageries, monitoring of the impacts of disasters such 
as earthquake, flood and forest-fire on forest resources over larger areas have 
become feasible. Besides, a joint effort amongst the concerned organizations is 
needed to better understand the impacts of such disasters on forest resources.