“Forest sector underutilized, says World Bank report” is the title of the story ran by Kuensel on July 25, 2019. If the World Bank’s report read “forest sector underutilized,” it calls for a much broader debate. Dr. Tashi Wangchuk’s opinion in Kuensel, titled “cutting more forest is not the most expedient choice” (August 3, 2019) sums up the need for looking at our forests as an asset at par with our built assets.
First, it is important to get the numbers straight. Many commentaries reflect that only 5% of the total forest area in Bhutan is currently under commercial management. This is not correct, as it should read as “5% of the country” and not “forest area.” In Bhutan, Forest Management Units (FMU) are commercial forest management regimes and besides FMUs, we have Local Forest Management Unit (LFMU), and Community Forests (CF). Thus, considering LFMU and CF together with FMU, almost 10% of the country and 14% of the total forest area is under forest management regimes in Bhutan.
Similar to Kuensel’s story on World Bank’s report, Dr. Phuntsho Namgyel’s talk on “Cut trees, save forest: a call for a new forestry thinking in Bhutan” delivered during the second BLISS Bhutan talks on 5th May 2019 in Thimphu drew many attentions. Having read through many comments on social media, both for and against the radical approach presented, I will make an effort to outline some of the intricate contributions forests makes.
Rainfall is considered the major cause for most of the landslides. However, vegetation acts as natural bioengineering structure to prevent slope failures. A simulation exercise carried by a Swedish scientist demonstrated that higher root density with higher root reinforcement results in a more stable slope.
However, the contribution of roots on slope stability is effective only when the tree is living. Studies have revealed that after a tree dies, the favourable effects on the soil water potential regime are lost immediately, increasing the potential landslide hazard. While tree cover helps in reducing landslide hazard, its contribution to groundwater recharge has remained still a subject of debate.
Transpiration and ground water
The interactions between forest change and water have been studied for over a century and many published works describe forests as ‘sponges’ storing rainwater and slowly releasing it to maintain groundwater and streams during dry periods. However, in recent decades, the ‘sponge’ theory lost credibility as studies increasingly showed that forest clearance generally leads to increase and afforestation to reduce water yields.
For example, a global study pursued by some American scientists, found that annual runoff reduces on an average by 44% (±3%) and 31% (±2%) when grasslands and shrub lands were afforested, respectively. In another study conducted by a group of scientists, wherein they synthesized more than 600 global observations, documented substantial losses in streamflow with afforestation: decrease in streamflow by 227 mm per year globally (that’s about 52%), with 13% of streams drying completely for at least a year after the plantation programs.
The reason for inverse relations between tree cover and stream flow is attributed to transpiration. Plant scientists estimate that transpiration produces 80–90% of the atmospheric moistures, indicating the role of transpiration in recharging atmospheric moisture, contributing to rainfall locally and in distant locations. It is estimated that on an average, at least 40% of rainfall over land originates from moistures contributed by transpiration and the proportion increases to as high as 70% in Amazon forests.
Though ground water is lost through transpiration, forests may be particularly important for high altitude areas as forests have a special ability to intercept fog and cloud droplets. Condensation on plant surfaces, including on dense, epiphytic lichen and moss communities – which are plenty in our forests, provides additional moisture for tree growth, infiltration, and groundwater recharge. High altitude forest loss may thus have disproportionate, negative implications for water availability, however, this warrants a localized and much deeper study.
According to the 2017 forestry facts and figures, Bhutan recorded 31 forest fire incidences, and similarly, 39 forest fires were recorded in 2018. However, in 2016 Bhutan witnessed 72 forest fire incidences which translate to one forest fire every fifth day.
Several scholars have argued that failure to remove small logs through performing thinning operations results in retention of ladder fuels that support crown fires. Crown fires are the most destructive kind of forest fires, as, it not only destroys habitats of threatened and endangered species but smoke from the forest fire increases atmospheric carbon.
However, there exists another group of literature, which are not in sync with the argument of thinning and logging operations minimizing the risk of a forest fire. This is because logging operations not only alter microclimatic conditions, but also can change stocking densities and patterns of trees, inter-crown spacing, and other forest attributes such as plant species composition. These changes can, in turn, influence fire regimes. There exist some studies to support this from North America, eastern Australia and, some part of, rainforests of Asia.
The annual report of Natural Resources Development Corporation Ltd. reported of increased timber production in 2018 from 2017 by 24,947 cubic meters surpassing the target of 52,725 cubic meters. Besides timber, NRDCL also produced 3727.70 MT of woodchips and 32,949.91 cubic meters of firewood. In 2017, the Annual Allowable Cut (AAC) was 218,046 cubic meters of timber.
This being said, timber shortage in Bhutan hit the headlines of the country’s media for quite some time now. A study found that from 1996 – 2011, 59% of the total volume of wood consumed in Bhutan was met by domestic production, and however, the remaining 41% of wood came from India. The study also revealed that, in 2009 and 2011, 75 and 77 % respectively, of wood consumed domestically was imported from India.
Forest is abundant resources Bhutan has, and the domestic demand for wood could be met from the country. However, Bhutan is geographically located in one of the fragile landscapes on earth, prone to climate hazards. The potential use of protection forests to combat shallow slope instabilities is increasingly important and relevant and should be seriously considered.
A landslide brings many ecological disasters which are intricately linked to economics, social and cultural landscapes. For example, an increase in the incidence of landslides and debris flows leads to injection of sediment into river systems. This not only deteriorates an aquatic habitat but also impacts hydropower, tourism, and agriculture, all of which are the major contributor to Bhutan’s GDP.
We have just observed a series of landslides due to the heavy monsoon across the country. Studies say it is aggravated by climate change and we have seen the consequences of landslides. In such a scenario, we need forests to reduce landslide hazards. If we continue with our argument, it will ultimately funnel to one conclusion: we need to conserve the forest. Conserving forest means conserving biodiversity – biodiversity plays a functional role in providing ecosystem services such as air, water, food, shelter, sequestering carbon, etc. This means we secure our future so long as we have forests – the very reason why life on the desert is scant!
While I agree that we need to produce enough timber to at-least meet local demands, I also believe that we need to have good forest cover considering the fragile landscapes we are in. Thus, we need to relook at our timber market and harvesting modalities to make timber available and affordable to our people.
We may achieve this, not necessarily by cutting more trees, but by investing in our timber harvesting and conversion machinery. We cannot go on, for long, with some obsolete machineries and keep on accepting the timber recovery volume for broad-leaves species to be only little over, just, 50%. Doing this will not only achieve in producing timber but will also ensure in maintaining our forest cover with rich biodiversity in perpetuity.
There are many questions that need answers and until such time it may be the best to leave nature function on its own. However, the existence of a contradictory array of literature calls for a localized study to understand the best practices for our forests and ecosystems. It is about time to invest in a policy driven research.
Viewing our forests from the economics lens or bankers’ perspective would lead to an ecological disaster and the economies of the Earth would grind to a halt without the services of ecological life-support. I shall leave it up to the readers to decide how you would prefer to view our forest cover: as natural capital or as an exploitable resources.
Charles Sturt University
New South Wales