Is deforestation a necessary evil? Part 1

Welcome to the last post within this blog (although it has been split into two parts because it is of considerable length). Way back in the realms of early October this blog set out an assortment of slightly related aims: explore the consequences of deforestation; examine whether the effects of deforestation are always bad; explore solutions; look at past patterns of deforestation and examine how complicated the discourse on deforestation is. They have all been examined in one blog post or more and now it is time to draw conclusions and thought from what this blog has researched. The overarching question of this blog, and the title of this post - is deforestation a necessary evil? - shall be finally answered.
This blog post will examine four key areas of interest that have been discussed throughout the blog:

1. The relationship between global environmental change and deforestation. 
2. The relationship between humans and deforestation.
3. Why deforestation is a bad process.
4. Sustainable Deforestation and Is a tree apocalypse inevitable?

Drawing upon references and ideas discussed in other blog posts will bring in an element of repetition but it is ultimately a post to explore my personal opinions towards the topics being discussed, in conjunction with academic research. 

The Relationship between Global Environmental Change and Deforestation

Trees, and vegetation generally, are an integral part of the Earth system involved in various cycles including the hydrological cycle, carbon cycle, nitrogen cycle and countless ecological cycles/systems. 

The importance of trees in the global nitrogen cycle (source)

In terms of carbon, trees act as a major carbon sink taking up carbon dioxide during the process of photosynthesis (Malhi et al. 2008). 150-200 Pg of carbon is stored in the Amazon within biomass and soils (Brienen et al. 2015). This study demonstrated the importance of trees as well as other vegetation and biomass that stores carbon and questioned the future of carbon sinks within the Amazon. 

Deforestation removes this store of carbon and releases it into the atmosphere. It is estimated that 1.8ppm of atmospheric carbon can from deforestation of the Amazon (Exbrayat and Williams 2015). Fueling climate change will have a positive feedback mechanism in which a warmer world causes increased drought (and wildfires) in the tropics leading to the destruction of more forests which in turn release their stored carbon (Haog 2009). 

The effect of deforestation on regional climate is also severe with increased surface temperature (due to reduced albedo) leading to a decrease in evapotranspiration and precipitation. A reduction in cloudiness and increases in insolation creates an increase in high pressure systems and frequent droughts. Furthermore, the alteration of the land surface increases wind speeds and therefore desertification and soil erosion (IPCC 2007; Malhi et al. 2008; Shukla et al. 1990). 

Trees impact on climate and vice versa and are an important factor in influencing global climate - the Amazon is the engine for global atmospheric circulation - and an alteration to this precious system would change our climate. 

The Relationship between Humans and Deforestation

Like the mighty oak, human beings have become an integral part of the Earth system (see their influence in the nitrogen cycle diagram) and have an impact on the climate and landscape more so than any other species. 

The causes of deforestation have been discussed extensively whilst the relationship between urbanization and deforestation in Africa has also been explored. 

The reality is that like oil, food and water, the human population needs trees as a source of fuel (e.g. firewood), shelter and for basic necessities (paper, furniture etc.). It has been at the core of our civilization for thousands of years and the relationship between humans and the threes is as delicate as their relationship with climate. 

I won't drone on about this in much detail with two blog posts already exploring societal collapse on Easter Island and in Mayan Central America but a brief recap won't hurt. There are numerous studies that contribute the collapse of Mayan society to deforestation (Haug et al. 2003; Ogelsby et al. 2010; Shaw 2011). The studies illustrate how important trees are in local climate - influencing drought. However, archaeological evidence and paleoenvironmental evidence is not always complementary and their are disputes as to whether deforestation alone contributed to the collapse of Mayan society (MacNeil et al. 2009). In reality it was probably a combination of socio-economic and political factors exaggerated by detrimental environmental effects such as drought that was caused by over-deforestation. 

I have already suggested that the attitude past societies (such as the Mayans and the Polynesians) had towards deforestation is much the same as our own and that there is potential for us to eventually cut down all the trees. 

A quirky diagram to illustrate MacDonald's arguement (Cool Geography)

Humans need trees (as I have mentioned already) and an article by MacDonald (2012) offers a concise synthesis of the relationship between humans and climate change. He notes that the humble tree is a hindrance to human societal expansion (in terms of space) as well as food production but that without trees mankind could not survive. Trees create an idyllic and comfortable in which human beings can frolic and grow by taking in heat during photosynthesis. He interestingly draws upon the dated works of Thomas Malthus to explore how human populations grow and survive. MacDonald further offers a controversial (yet logical) view point to combating deforestation and climate change saying it is the responsibility of world leaders to keep the world's population in decline in order to ensure a good quality of life for the current population. I think for MacDonald, the root cause of the world's problems is overpopulation (draining resources, taking up space, degrading the landscape and producing pollution). To some extent he is correct but there are definitely alternatives to controlling population and implementing anti-natalist policies. 

It is true that we need trees for survival but I think (and this will be discussed later) we can do more to manage the way in which we use trees. What I want everyone to take from this post (is not the doom and gloom population comments) but that trees are vital in the Earth System and that everything is interlinked. 

The remainder of this posts (questions 3+4) will be explored in "Part 2" but please feel free to comment and vote on the poll in the top left of the screen - it will be interesting to see what everyone thinks. 

Man and Tree: The relationship between deforestation and humans in Africa

Modern humans have occupied the continent of Africa for over 200,000 years and their relationship with nature is quite interesting. In this blog post I will talk about the relationship between deforestation and humans in Africa and also explain the current trends in deforestation.

Humans are deeply implicated in deforestation in Africa (source)

There is a long history of human interactions with the forests of Africa and despite a reliance on wood for fuel there are generally low rates of deforestation. Two articles by Malhi et al. (2013) and Rudel (2013) act as the basis for this blog post. Both academic papers document deforestation in Africa extensively and thoroughly whilst also successfully comparing it to other deforestation prone areas of the world such as Latin America and Borneo.

Malhi et al. talk about how 1900 years BP there as a population collapse following centuries of deforestation and burning (similar to what happened to the Maya?). As a result the forest regrew and recovered in a matter of centuries. This is incredibly interesting because we do not see this kind of recovery in other parts of the world (as noted by the authors). This pattern of deforestation and regrowth occurs throughout different periods of of Africa's history and reflects how humans and nature are entwined.

A more modern history of deforestation has been documented in Rudel's study which examined rates of deforestation between 2000 and 2005 (a quite short period). However, the author notes that studies into deforestation prior to 2000 are unreliable because measures of forest losses were different between countries.

Is urbanization the hero of deforestation in Africa?
One would not think of the unstoppable force of urbanization as a hero for environmentalists but in Africa it seems to be the case. Rates of deforestation in sub-Saharan African are lower than anywhere else in the tropics and it is because deforestation is caused by expanding rural populations. However, when work and a better quality of life pull people to the city, rural communities are declining rather than expanding and thus rates of deforestation are decreasing.

Projections of Africa's Urban Population (World Bank)

Deforestation is concentrated to peri-urban areas, transportation axes and rivers. In the poorest sub-Saharan African countries an absence of state led infrastructure compared to other countries might explain the persistently lower rates of deforestation. Although there is no data to support this conclusion.
In countries such as Nigeria "dutch disease" occurs where a booming commodity such as oil pushes farmers out of business due to reduced market share and high wages. As a result farmers move from agricultural livelihoods to the city or into the oil sector and with less agriculture comes less deforestation. A booming extraction sector would discourage expansion into forests.

From agriculture to oil - there is more money in working for the oil companies (source)

These two articles offer interesting and complementary pieces of research into deforestation in Africa. Both provide succinct summaries of deforestation in Africa (mostly focusing on sub-Saharan Africa) with several potential reasons to explain lower rates of deforestation.
This post also follows on nicely from last weeks post about a decline in deforestation worldwide and the articles offer some interesting statistics:

• Rates of deforestation in Africa = 0.049%
• Rates of deforestation in Latin America = 0.25%

Global Deforestation Trends

The first post on this blog will probably be the most cringe-worthy but its purpose is simple - to set the scene for future blog posts.


Deforestation is defined as the clearing of forest into cleared land. It is a heavily discussed topic since it is embroiled in the global carbon cycle and hence global climate change. This blog will not offer descriptions of global processes but facts, opinions and up-to-date academic research into the various issues surrounding global environmental change.

It is estimated that 11.5 million hectares of forest, an area the size of Portugal, is removed through cutting or burning and questions arise from this:

• Is deforestation always bad? Perhaps it is a necessary evil?
• What are the consequences of current deforestation patterns?
• Is reforestation an option for this generation?
• How have past patterns of deforestation influenced global environmental change?
• What about the plants and animals?

A blog about controversies summaries logging debates nicely, although it lacks scientific depth. It can be found here.

The removal of ancient trees that have stood for longer than some human civilizations appears to be wrong. How could humans destroy a carefully constructed piece of nature in just minutes?  The truth is that deforestation is not a pointless evil. It has a purpose and it is to supply wood to the planet's burgeoning population and to create space for the rapidly urbanizing metropolises of the 21st century. If we want to stop deforestation surely we should look at the uncontrollable population booms in the developing world and the unplanned expansion of our mega-cities.

Logging in Brazil (National Geographic)

Deforestation and Climate Change

The main debate and smaller arguments surrounding deforestation have now been put forward and these shall be discussed in future blog posts. The link between deforestation and climate change is relatively simple.
Plants and trees remove carbon dioxide from the atmosphere. If trees are cut down then less carbon dioxide is removed from the atmosphere and therefore the planet gets warmer. Furthermore, the burning of sections of forest releases stored carbon dioxide into the atmosphere, accounting for the second largest contribution of CO2 to the atmosphere, after fossil fuel combustion (Van de Werf et al. 2009).


This blog will also examine the future of deforestation? Can it be stopped? Is there an alternative?