Nyanza to bear brunt of climate change due to low forest cover

A woman carrying firewood in Miwani on April 19, 2016. Firewood is the main source of fuel for many families in the area, leading to deforestation. PHOTO | TOM OTIENO | NATION MEDIA GROUP

What you need to know:

  • A 2006 International Forestry Resources Institution report put the estimated deforestation rate at 200 hectares a year not just in Gwasi, but in the whole of Western and Nyanza regions.
  • So serious has the deforestation been that the National Museums of Kenya stepped in and took control of the Thim Lich Ohinga Forest, which straddles Ndhiwa in Homa Bay County and Nyatike in Migori.
  • In the 2015 last quarter report by the weathermen, a write-up by James Kongoti, the director of the Meteorological Department, warned that the counties in the western region would experience “highly enhanced rainfall”.

Ever since Mary Onyango relocated to Kisumu from Nyeri last year, she feels “mentally disturbed and my face is losing its glow”. And she is convinced it is because there are fewer trees in Kisumu.

There could be some truth to her words, strange as it might sound: a report published last year by Stanford University in California shows that people who spend time outside in green, natural spaces tend to be healthier and happier than those who do not and it is well known that trees purify the air by absorbing carbon dioxide.

Notably, Nyeri County has 10 times the number of trees in Siaya, Migori, Homa Bay and Kisumu counties combined. In Nyeri County, 38.03 per cent of the land is covered with trees, according to a 2015 mapping of forest cover report by the Kenya Forestry Service (KFS). This means that Siaya County, with only 0.42 per cent, would have to plant 90 times the numbe of trees Nyeri has to attain that green ambience.

With tree covers of 0.42 (Kisumu), 2.62 (Kisii) and 2.59 (Homa Bay) are not doing any better.

These four counties, plus Busia County, have the lowest tree cover in the country while Nyeri, Elgeyo-Marakwet (37.49), Lamu (33.9) and Baringo (25.12) have the highest.

With a tree cover of 7.29 per cent, Nyamira is the only county in Nyanza that exceeds the national average of 7.14 per cent.

Given these low figures, environmental experts now warn that the residents of Nyanza have a reason to worry.

Dr David Langat, the deputy regional director at the Kenya Forestry Research Institute (Kefri) in charge of the lake Victoria Basin — which covers the former Nyanza and Western provinces — says serious deforestation has taken place.

He singles out Gwasi as an area that was once forested but has lost many of its trees to human settlement.

The residents of Gwasi also talk of two forest fires that gutted 5 hectares of Ramoya and 12 hectares of Kigwa blocks of Gwasi Forest.

A 2006 International Forestry Resources Institution report put the estimated deforestation rate at 200 hectares a year not just in Gwasi, but in the whole of Western and Nyanza regions.

Kefri’s current estimates put the little pockets of trees left at just 12,000 hectares.

In Ndhiwa Constituency, trees have been cut not only for traditional construction, but also for the booming brick-making business, which requires a lot of wood for kilning.

In addition, the local people rely heavily on wood fuel, which encourages charcoal burning.

Kanyikela area Member of County Assembly in Ndhiwa Sylvance Wanjala told DN2 that a brick costs Sh6, and a simple, one-bedroom house requires more than 3,000 bricks.

“It is booming business, and those prices will shoot up really soon,” he said.

So serious has the deforestation been that the National Museums of Kenya stepped in and took control of the Thim Lich Ohinga Forest, which straddles Ndhiwa in Homa Bay County and Nyatike in Migori.

While the situation is changing, Dr Langat says, it will take long due to the people’s attitude.

“Here, people believe trees just grow on their own, so they will cut down a tree with no plans of replacing what they have cut and when they plant, they wait for the tree to thrive on its own,” he offered.

But the apathy with which people view trees is not unique to Nyanza.

Dr Wanja Kinuthia, an entomologist at the National Museums of Kenya in Nairobi who has studied the role of plants in sustaining pollinators, had told DN2 in an earlier interview that, coupled with the apathy that most Kenyans have towards nature, the science of how one tree can affect their lives is difficult to grasp.

“Sometimes people plant trees alright, but they choose the wrong species that end up making ‘dead forests’ because they are the types that do not encourage life underneath them and impoverish the soil instead of enriching it,” she said.

The link between human wellbeing and trees is a concept that many ordinary Kenyans fully understand.

Noting that trees absorb greenhouse gases from the atmosphere, Dr Lang’at said Nyanza will have to battle the negative effects of climate change as it tackles urbanisation, thanks to its poor tree cover.

Mrs Lorna Omuodo, the chief officer for Renewable Energy and Climate Change, pointed out that Kisumu, more than any other county in the region, will continue experiencing increased termperatures and prolonged rains due to the high amounts of methane gas in the air.
Speaking during the realease of a report on the gender perspective to climate change by Practical Action and Institute of Development Studies, she attributed the dangerously high levels of methane to the careless disposal of organic waste by residents.

“It is littered everywhere, and this gas is warming the county aggressively,” Mrs Omuodo said.

Methane, which is produced when plant and animal waste decomposes, is “20 times more potent” than carbon monoxide, according to the United Nations Environment Programme.

Methane stays in the atmosphere for a maximum of 12 years and has a direct impact on human health.

While Mrs Omuodo did not say by exactly what margin the temperature would rise, but her fears are not unfounded, going by data from the Kenya Meteorological Department and studies. Besides, while collecting data for her thesis at Kenyatta University in 2014, Millicent Ochieng’, an environmental science Masters student, found that temperatures in Kisumu rose by an average of 0.66 degrees Celsius every month from 1972 to 2011.

The data, collected at Kisumu Weather Station Number 9034025, also indicated that the rains increased by 115 millilitres during that period.

Kisumu residents frequently complain of the heat and erratic rainfall patterns, which climate change experts attribute to the release of greenhouse gases such as methane into the air, among other factors.

The reason this is likely to affect Kisumu more than the other counties, she said, was the rapid industrialisation.

“There is no known structure that explains what happens to all the leftover food from these hotels, supermarkets and houses that are built in this city every day.

Add to that the market days in Sondu, Awach, Ahero and other places… where does all that waste go?” she wondered.

Indeed, Kisumu remains the biggest economic powerhouse in the region, with a population of 952,000, according to the 2014 economic survey. She singled out the sites that should “give people sleepless nights” as “Behind Kibuye Market where people keep molasses, the slaughter house in Mamboleo, and the Kachok dumpsite.”

In the 2015 last quarter report by the weathermen, a write-up by James Kongoti, the director of the Meteorological Department, warned that the counties in the western region would experience “highly enhanced rainfall”.

And sure enough. Kisumu recorded 775m, which was double the usual amount (113 per cent).

But lack of trees does not lead only to the retention of high levels of methane in the atmosphere. Cutting trees releases stored carbon dioxide that had already been absorbed back to the atmosphere, contributing to further heating.

Thus the increasing temperatures in Nyanza cannot be blamed solely on of the low forest cover.

Johanes Onyango, who lives near Ranen Forest in Rongo, likes it because it receives rainfall, when the adjacent areas such as Rakwaro are dry. The elderly man cites Kaksengere, Mbaga and the Kanyamwa escarpment as places he would not mind living in because they, too, receive rain when the other areas are dry.

Notably, they are all heavily forested.

“I think these trees just bring rain,” he says, unaware of the complex science behind his observation.

This is the concept of “flying rivers”, which says that trees take up moisture from the soil through their roots, and release that water into the atmosphere through their leaves.

The plants also have volatile compounds called terpenes and isoprenes.

In fact, it is estimated that a tree in a rich ecosystem such as the Amazon or Congo forest releases 1,000 litres of water vapour into the atmosphere every day. And it is this vapour that creates clouds. The vapour “matures” thanks to the activity of the volatile terpenes and isoprene. With the help of winds, these water-carrying clouds can travel further than the eye can see, hence the name “flying rivers”.

These rivers move over water bodies collecting more moisture until they bump into each other at some point and bring rain.

Though the dynamics are not well understood, there is also the term “biotic pumping”, used by authors like Jim Robbins, who wrote the book, The Man who Planted Trees.

It is a mechanism, through which natural forests create an control the movement of wind from large water bodies to land, thereby bringing moisture to land. So when trees are cut, this system is interfered with, leading to lack of rainfall.