Trees of life

  • February 4, 2015
Trees of life

Martin Kaonga talks about his role as an expert in carbon biogeochemistry and climate change.

Martin Kaonga has come a long way from his childhood days in a remote village in northern Zambia with just 200 households to his current role as an expert in carbon biogeochemistry and climate change.

Martin is Director of Conservation Science at A Rocha, an international Christian conservation organisation, where he is responsible for conservation science research and applied conservation projects in 20 countries, including Ghana, France, Canada, Brazil, India and Kenya. In Ghana, for instance, he is overseeing work on the long-term impact of forest restoration on biodiversity, carbon sequestration and local livelihoods.

Martin, whose background is in plant biodiversity and carbon dynamics in terrestrial ecosystems, has edited a book on agroforestry and ecosystems services and published peer-reviewed papers since working at A Rocha.

He joined the organisation as Conservation Projects Director, running two major programmes: a climate stewards programme, which reforested degraded forests in Ghana, Peru and South Africa as a way of reducing atmospheric carbon concentrations, and a biodiversity assessment and conservation programme in Papua New Guinea which resulted in the discovery of over 200 species that were new to science.

The climate change programme involved assessing baseline carbon stocks, biodiversity and community benefits and modelling carbon stocks over a 50-year project life span.

In 2009 Martin was promoted to Acting Director of Conservation Science and in November 2010 he was appointed Director of Conservation Science.

The role builds on his PhD from the University of Cambridge, which he completed in 2005. It focused on modelling and field-based measurements of plant and soil carbon changes in agricultural, agroforestry and miombo woodlands in Zambia. “I wanted to understand how tree diversity contributes to the carbon dynamics in terrestrial ecosystems,” he says. That includes developing models for measuring carbon storage and fluxes in plants and soil carbon models to predict changes the soil carbon.

Martin, who is based in Cambridge but travels regularly, came to Cambridge after spending years teaching subjects ranging from agricultural science to agroforestry at diploma and undergraduate degree level at the University of Zambia and its affiliated college, the Natural Resources Development College, in Zambia.


When he was a child, however, he would never have thought he could have achieved so much. Born in Kaseya, a remote village with less than 200 households, in the Isoka district of northern Zambia, he was the first in his family to go to university. His father, a primary school head teacher, emphasised the value of education from an early age.  Because of his father, Martin, the eldest of eight children, started school two years early. Indeed he was told to leave the class if the inspectors came around because he should not have been there.

His years in school were not easy, though. His father was his teacher for much of his primary education and was extremely strict. He reserved a special seat for Martin in his class so that he was not influenced by the other students. The bar was set higher for him than for them. Even if he got the highest score on class tests, he would be beaten if he got some answers wrong and would have privileges at home withdrawn, such as going out to play.

When Martin got to year four he had to sit government exams. Only the top 35 10 and 11 year olds from three schools in the area were able to continue their education. The next school he attended was around 100 kilometres away and the family moved so that Martin could attend. His father was transferred to a bigger primary school as deputy head.

At the end of year seven there was another government examination to sit for entrance to secondary schools. Only 180 students from all the schools in the district were picked. A lot of students in Martin’s year failed or had to resit. Only three out of 48 in his class passed and Martin was the only one who passed without a resit.

The secondary school was three and a half hours away by bus and Martin had to board. He had never been away from home and on his first day at the school he was kicked by some of his seniors. First-year students were treated very badly by the older students. He was forced to do chores, beaten up and woken up in the night. “They were trying to break us down so we would obey our seniors,” he says. The regime eased as he got older, but the school was very strict with regard to academic studies. Students had to do a minimum of two hours supervised study every night.

Early career

Martin really enjoyed maths and science. Before he went to secondary school he had no idea about different careers. His village was totally cut off when he was very young and the family would only rarely venture out of it. He got careers advice at secondary school and realised he had an interest in agricultural sciences.Between school and university, however, he got drafted into the Zambia National Service for military training. At the time, Zambia was helping neighbouring countries with their independence struggles and was hosting a number of organisations, including the ANC. British colonies, South Africa and Southern Rhodesia (now Zimbabwe) were bombing Zambia and the Zambian military did not have enough soldiers so all secondary school graduates had to go for military training until they had been admitted to tertiary education.

After six months in the military, Martin was accepted on a college course as a trainee secondary school teacher. Two months later he was admitted to the Natural Resources Development College in Lusaka where he registered for a three-year diploma in agriculture, majoring in animal science. He was the top student on the course and was offered a job as a Livestock Officer in Veterinary Department of the the Ministry of Agriculture, Food and Fisheries after he finished his diploma.

Once there he transferred to the Department of Training and worked at his old college as a practical instructor and a poultry manager at the college farm. His academic career progressed when he won a scholarship to do a BSc in agriculture at the University of Malawi, specialising in animal breeding. It was a five-year programme, but because Martin had a diploma, he completed the degree in three years. After completing his programme, he attended a five-month animal breeding training in Japan on a JICA Scholarship.  As part of the scholarship, he had to return to Zambia on completion to teach.

He then applied for another scholarship from the International Centre for Research in Agroforestry (ICRAF) to do a masters in agroforestry in Ghana so that he could develop an agroforestry course at the college. It was in the mid-1990s and there was a move towards integrating trees into farming systems given their role in soil conservation, animal nutrition and improving food security.

Martin studied the effect of tree leaf hay supplementation in vivo and in vitro digestibility of rice straw and the impact on the growth characteristics of sheep.

It was the first time Martin had travelled to a country that wassubstantially different to his own. Malawi was not only fairly similar to Zambia, but his mother was born there and his father did his teacher training there. During his time in Ghana he suffered a family tragedy when his sister suddenly died. He found it very difficult being so far from his family at the time.


Martin returned to Zambia to teach for three years and then spent a year teaching and developing the agroforestry course at the University of Zambia before applying to do an MPhil at the University of Cambridge. He chose Cambridge as one of his professors in Malawi had advised him to apply years before. “I thought I was very clever, but I had never heard of Cambridge at the time,” he says. When the professor got a job in Zambia he again told Martin to apply to Cambridge and said he would give him a reference. “He literally forced me to apply,” laughs Martin. He was offered a place, but had no funding so he applied again and was accepted to do an MPhil in Environment and Development supported by a Joint Japan/World Bank, Commonwealth scholarship.

Although he already had a masters, he felt an MPhil would be a stepping stone to a PhD and as soon as he arrived at Cambridge, he asked his supervisor about applying for a PhD. He says coming to Cambridge was a bit of a culture shock – in African countries where he had studied, lecturers were more direct in their advice while in Cambridge they more or less suggested what could be done rather than telling students what they should do. Moreover, he had only just started learning to use a computer when he arrived. “My fellow students were using laptops. It was a steep learning curve,” he says.

Martin applied for a PhD, but missed the timetable for scholarships because his results came out too late. However, when they did come out and he was the top student on his course he was told he would be found a scholarship if he deferred his programme for a year. He stayed on in the UK for three months and during that time the Gates Cambridge Scholarship was launched.

Unlike other scholarships, it has no age limit. Martin, 39 at the time, applied and left for Zambia. He was awarded a scholarship without an interview because of his results and started on his PhD in 2001, based in the Geography Department. His PhD cut across disciplines including plant sciences, earth sciences and biochemistry. While in Zambia, he changed his research topic, but informed his supervisor after returning to Cambridge. Because the new topic was beyond the expertise of his supervisor, he had to knit together several experts who could advise him, including the organisation which had sponsored his research in Ghana.

Martin had to leave behind a young family in Zambia to come to Cambridge. He was able to travel to Zambia to do his fieldwork in his second year and brought his wife and three children over to the UK in his third year. His PhD took slightly longer than three years because of a delay in getting his soil and plant samples analysed in Nairobi.

After finishing it, he started working at an independent sixth form college in Cambridge during term time, preparing learning resources for students and doing one-to-one teaching before taking the role at A Rocha. He hopes to continue his work in biodiversity conservation and climate change.

Picture credit: S. Thomas for A Rocha

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