- Commentary -

Real-world complexity of food security and biodiversity conservation

Jan Christian Habel1*, Mike Teucher2, Berthold Hornetz2, Ralph Jaetzold2, Josphert N.

Kimatu3, Sichangi Kasili3, Zachariah Mairura4, Ronald K. Mulwa3,5, Hilde Eggermont6,7, Luc

Lens8

1Terrestrial Ecology Research Group, Department of Ecology and Ecosystem Management,

Technische Universität München, D-85354 Freising-Weihenstephan, Germany

2Department of Biogeography, Trier University, D-54286 Trier, Germany

3Biological Department, South Eastern Kenya University, P.O Box 170-90200, Kitui, Kenya

4Department of Agribusiness and Market Development, Ministry of Agriculture, P.O Box

30028, Nairobi, Kenya

5Department of Ornithology, National Museums of Kenya, KE-40658 Nairobi, Kenya

6Belgian Biodiversity Platform, Royal Belgian Institute of Natural Sciences, B-1000 Brussels,

Belgium

7Limnology Unit, Department of Biology, Ghent University, B-9000 Ghent, Belgium

8Terrestrial Ecology Unit, Department of Biology, Ghent University, B-9000 Ghent, Belgium

*Corresponding author:

Jan Christian Habel, Terrestrial Ecology Research Group, Department of Ecology and

Ecosystem Management, Technische Universität München, Hans-Carl-von-Carlowitz-Platz 2,

D-85354 Freising-Weihenstephan, Germany; E-Mail: Janchristianhabel@gmx.de

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Keywords: climate change, biodiversity conservation, colonial legacy, cultural legacy, soil

fertility, demographic pressure, food security, Kenya, post-harvest

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ABSTRACT

Feeding the booming global human population and in parallel conservation biodiversity is a

global challenge. Yet, it is particularly acute in developing countries where biodiversity is

highest and food-security low. There is an ongoing debate whether land for nature and for

production should be segregated (land sparing) or integrated (land sharing, wildlife-friendly

farming). While these strategies still need unambiguous empirical validation, we here

illustrate the real-word complexity of this issue by focusing on Kenya, East Africa. We

analyse multifacetted conflicts between the increasing demand for food on the one hand, and

nature conservation on the other. We discuss the effects resulting from the country’s past

history, the recent and ongoing demographic pressure, limiting factors related with biotic and

abiotic conditions like low soil fertility and strong climatic amplitudes. We propose actions to

promote sustainable food security within a Kenyan context, to free up land for conservation

concerns. Our study stresses the importance of recognising the specific context in which land-

use strategies are to be applied, and underline the need of a deeper understanding of local

conditions – apart from the theoretical and highly abstract land-sparing land-sharing debate.

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INTRODUCTION

The growing human population is demanding for more food, feed and fuel, as well as for

more resource-intensive diets like meat and fish (Godfray et al. 2010; Tilman et al. 2011).

Recent studies suggest that food production, which is an important component of food

security will need to increase by 70-100% by the year 2050 in order to feed the global human

population (World Bank 2008; Royal Society of London 2009). The production of biomass

for regenerative energy sources (such as biogas and bio-fuel) and climate change effects

further aggravate this situation, and have resulted in a dramatic increase of food prices at the

global market in recent times (Garnett et al. 2013). Concurrently, the expansion of agricultural

areas caused a rapid decline of biodiversity during the past decades (IUCN 2009; Brussaard et

al. 2010; Habel et al. 2013).

The ongoing debate among scientists and policy makers on how to reconcile food security and

biodiversity conservation, and hence, to produce food in a more biodiversity-friendly way,

has resulted in two main alternative strategies (Godfray et al. 2010; Garnett et al. 2013). The

first approach argues that the already existing cultivated land has to be used more intensively

(but nevertheless sustainably). Authors in favour of this strategy argue that the demand for

more food can be met by an increase in productivity in terms of improved use of light, water,

nutrients, and mechanization, without a need for more agricultural land (Garnett et al. 2013).

This approach is most commonly termed the “sustainable intensification” (Godfray et al.

2010), but is also known as “land sparing” or “intensive agriculture” strategies (Garnett et al.

2013), as areas for food production are separated from areas which are of high conservation

value. A second approach, however, assumes that biodiversity at the landscape level is pivotal

to sustain both, agricultural production and the provision of ecosystem services, and therefore

advocates extensive rather than intensive production, i.e. by applying eco-agricultural

techniques and organic farming. This approach has been termed “land sharing”, “wildlife

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friendly farming” (Tscharntke et al. 2012), or “eco-agriculture strategies” (Brussaard et al.

2010), and states that food production can be reconciled with the conservation of biodiversity

functioning (Tscharntke et al. 2012).

Pros and cons of both strategies have often been discussed in a very theoretical, global and

often fairly simplistic way (Godfray et al. 2010; Phalan et al. 2011; Garnett et al. 2013). In

particular, discussions often seem to neglect the complexity of the history of single countries

and societies, the societal life and traditions, as well as local natural conditions. This

contribution summarizes thoughts developed during a workshop on food-security and

biodiversity for the semiarid regions of Eastern Kenya, held at the South Eastern Kenya

University Kitui. Participants from the fields of agro-economy and agro-geography, ecology

and conservation biology, soil-sciences and politics built a multidisciplinary cluster of

knowledge and views. Baseline for this workshop was a contribution by Garnett et al. (2013)

about “Sustainable intensification in agriculture: Promises and policies”. In the following we

highlight the real-world complexity underlying the conflict of food production and

biodiversity conservation within a Kenyan context. We analyse

(i) The cultural and colonialism legacy affecting recent food production in Kenya,

(ii) The impact of demographic pressure,

(iii) Effects from soil depletion and climate change,

(iv) The importance of locally-adapted agricultural techniques and varieties.

We finally bring together these aspects against the background of wasting of land and the

subsequent loss of pristine habitats including its biodiversity. We close by elaborating ways to

solve these global challenges on a local scale.

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COLONIAL AND POST-COLONIAL IMPRINTS

Current food insecurity and the loss of pristine habitats in Kenya have been partly driven by

its colonial history. Vast areas of prime agricultural land have been used for cash crop

farming with products mainly being exported to the world market (Jaetzold et al. 2010).

Examples of such areas include the coffee plantations in the Kiambu and Muranga districts of

the Central Province, the tea plantations in the Kericho district of the Rift Valley, and the

`White Highlands of Kenya´ (high altitude plateaus, like the Laikipia Plateau or the Uasin

Gishu Plateau) where large-scale wheat, barley and maize farming have been conducted since

the infrastructural development at the beginning of the 20th century (Jaetzold et al. 2006c

2011).

Until these highlands became occupied by the East Africa Protectorate in 1902 (Laube 1986),

they were originally populated by Masai groups. Many of them were translocated to semi-arid

and arid areas of Kenya. Similar translocations have also been reported for other ethnic

groups and regions, like the Nandi people in western Kenya, or the Kikuyu in central Kenya

(Thurston 1987; Kipkorir 1978). After independence in 1963, these large-scale human

translocations were only marginally re-adjusted and corrected (Kohler 1988). As a result, a

high proportion of the Kenyan human population still needs to settle in areas only marginally

suitable for food crop production, characterised by low soil fertility and high variability in

precipitation regimes (Jaetzold et al. 2006c).

ANCESTRAL LAND SPLITTING DILEMMA

This problem of the accumulation of Kenyans in areas being only marginally suitable for

agricultural production becomes further aggravated by the exploding human population,

which increased by 251% during the past 30 years, from 16.26 million people in 1980 to 40.9

millions in 2010 (FAOSTAT 2014). This disastrous demographic explosion continues until

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today and aggravates food insecurity as increases in crop yields are lower than the growth rate

of the human population. For example, maize production in Kenya increased from 1.62

million tonnes ha1 in 1980 to 3.6 million tonnes in 2012, a growth of 222%; however, in the

same time window, yields per hectare only increased by 138%, and the human population

almost tripled by 2012 (FAOSTAT 2014) (Fig. 1).

Due to the increasing population and the inherital traditions in Kenya, the sizes of the farms

have diminished by more than 50% from 1977 to 2004 (Farm Management Handbook of

Kenya; Jaetzold and Schmidt 1982-1983; Jaetzold et al. 2006a-2012). This has led to an

ancestral land splitting dilemma, and farmers have been forced to switch from crop rotation to

permanent crop cultivation, which increases the leaching of nutrients in soil and decreases the

yields. This precarious situation finally leads to decreasing soil fertility and finally ends in a

conflict between food security. In consequence, new – still fertile land has to be cultivated to

produce enough food and pristine habitats become populated (see below).

SOIL FERTILITY

The negative trend of crop yields observed for major parts of Kenya is mostly due to

overcropping and subsequent soil depletion (Muriuki and Qureshi 2001) (described above).

For instance, maize yields decreased by 40-60% within the last 30 years in the densely

populated rural areas of humid western Kenya despite the application of mineral fertilisers

(macronutrients N-P-K) (Jaetzold et al. 2006a-2012). Particularly, pH-figures were lowered

by the exhaustion of calcium, magnesium and other micronutrients during continuous

cultivation even in soils with initial high fertility. The application of macronutrients turned

out to be responsible for the depletion of micronutrients due to the spurt of plant growth

(effect of “agromining”; Jaetzold et al. 2010, p. 52-53).

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Apart from locally adapted crop varieties, low input practices (including improved fallows

using legumes in rotations or intercrops) can restore soil nutrients and reduce reliance on

fertilizer use by 50% (Carsan et al. 2014). Studies showed that intercropping with coppicing

legumes often has positive economic effects (Sileshi et al. 2008; Garrity et al. 2010). Whereas

unfertilized maize fields have a relatively low economic value (Correll 1997). Integrating

trees in agricultural landscapes, also known as agroforestry, may further boost productivity,

promote crop diversity, contribute to biodiversity and ecosystem services, improve water

regulation, and promote nutrient cycling and organic matter build up (Hegland and Totland

2005; Clough et al. 2011; DeSouza et al. 2012; Carsan et al. 2013, 2014). As a result,

agroforestry in Africa has often shown positive effects on crop yields such as maize (increase

by 200%) (Sileshi et al. 2008), ground nuts (increase by 37%) and sorghum (increase by

200%) (Garrity et al. 2010).

Whereas agroforestry can definitely provide solace in some cases, others might benefit more

from the application of fertilizer (Evenson and Gollin 2003), or by using new crop varieties

(Cassman 1999; IAASTD 2008). Examples from Kenya indicate that the availability and use

of fertilizer may have positive effects on crop yield (Fig. 2), provided that local soil and

climatic conditions are taken into account (Muriuki and Qureshi 2001). Besides the fertiliser

application rates, the type of crops, crop varieties, crop combinations, growing season and use

of manure are also determining whether or not fertilizer use will be successful. A holistic

approach, like the one used in the Integrated Soil Fertility Management (ISFM) (Vanlauwe

2004; Jaetzold et al. 2006a-2012) is hence of crucial importance.

Despite encouraging results, a stagnation or even decrease of crop yields has been observed in

many African countries during the past decades, where per capita food production fell back

from the mid 1970s and has now declined to the level of the year 1961 (Conway 1997;

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Evenson and Gollin 2003; McIntyre et al. 2008; FAOSTAT 2009). The use of fertilizer in

Kenya increased only marginally between the 1960s and the 1990s (FAOSTAT 2009) (in

comparison, the use of fertilizer in India increased from 10 up to 110 kg ha -1, and in China

even up to 240 kg ha-1 during the 1990s, MSU 1998).

CLIMATE

Crop yield from species like sorghum, millet and groundnut are primarily controlled by

climate (Mueller et al. 2012). Projected climate change is expected to negatively affect the

agricultural resources over major parts of Africa (Beddington et al. 2012; DeSouza et al.

2012; Gonzalez et al. 2012; Vermeulen et al. 2012), especially in the drier parts (IPCC 2012).

In some areas of Kenya, like the Kitui County in the south east, climate has already changed

during the past three decades (Jaetzold et al. 2012). As a consequence, a severe altitudinal

shift of the agricultural area has taken place with areas unsuitable for crop production

increasing by about 20% (Fig. 3).

Negative effects of climate change on crop yield can partly be attenuated by using appropriate

crop varieties, adapted to local climatic and soil conditions including drought tolerance

(Jaetzold et al. 2010), provided from several Kenyan institutions like the Kenya Agriculture

Research Institute (KARI). Today, more than 223 new maize varieties are officially registered

in Kenya (KEPHIS 2014), and about 50% of all harvested maize in Kenya comes from local

varieties (Waithaka et al. 2007; Sileshi et al. 2008).

NON-ADAPTED FARMING PRACTICES

Successful agriculture and high food security also strongly depends on the cultural legacy and

the respective practices of the farmers. Excessive stocking (e.g. of goats and cows),

cultivation of inappropriate crops or inappropriate crop rotations can damage the resilience of

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highly sensitive ecosystems and eventually turn them into semi-deserts, as shown for various

parts of Kenya (Hornetz 1997; Tittonell et al. 2005).

Moreover, whereas in developed countries food waste is mainly household restricted,

developing countries primarily waste food on farms, during transportation, processing and

storing (Godfray et al. 2010). Post-harvest losses of grains have accelerated strongly during

the past decades and are estimated to range between 20-30% of the produced food worldwide

(Jones 1981; Food and Agricultural Organization of the United Nations 2011). One out of

every five kilos of grain produced in Sub-Sahara African countries is lost to pests and decay

(Food and Agricultural Organization of the United Nations 2011). This lost food might feed

48 million people for 12 months, and is valued at around 4 billion US$ or half of the annual

grain imports to Africa (Food and Agricultural Organization of the United Nations 2013). The

problem of food waste could be solved by new storing and preserving techniques, like the

creation of small-scale metal silos for single households or local communities and villages

(Kimatu et al. 2013). In addition to an increasing food-security, this could lead to a surplus of

food-crops to earn money as it would allow farmers to retain their products for a longer period

and as such respond better to price and whether fluctuations. In this way, it would integrate an

entrepreneurial spirit in local farming activities, which could have a positive back-loop

towards increased education and higher life-standard.

THE DELICATE BALANCE BETWEEN YIELD AND BIODIVERSITY

CONSERVATION

Eighty percent of the hungry human population lives in developing countries, where the

demographic pressure is strongest and biodiversity highest (Cincotta et al. 2000). As a

consequence, human-wildlife conflicts in such areas are amply, as exemplified in Kenyan

Taita Hills, Kakamega Forest, and various National Parks (Thaxton 2007; UNEP 2009; Habel

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et al. 2013). However, protection of biodiversity per se is hard to justify when people are

starving, and are unaware of the causal relationship between biodiversity loss and food

shortage.

As described above, the conflict between yield and biodiversity in Kenya is multi-facetted and

driven by the country’s past history, ongoing demographic pressure, sensitive soil conditions,

strong climatic amplitudes, non-adapted farming practices and the lack of adequate logistics

(e.g. for food storage and/or transportation). The choice between land sparing, wildlife-

friendly farming and mixed strategies is highly abstract and theoretical, and therefore not

straightforward. Our study stresses the importance of recognising the specific context in

which land-use strategies are to be applied, and highlights that trade-offs between biodiversity

and yield are prevalent (cf. Phalan et al. 2011; Tscharntke et al. 2012). Likely, none of the

afore-mentioned strategies is a complete solution. Biodiversity conservation will still fail if

we expect it to be achieved solely as a by-product of other policies such as sustainable

intensification. In order to be successful, society will clearly need to integrate explicit

conservation objectives into local, regional and international policies affecting the food

system. Moreover, as multiple drivers and feedbacks can affect food security at a great extent,

we clearly need a deeper, scientific understanding on earth systems, natural systems, human

society, agricultural systems and their interconnections, so that well-informed and targeted

solutions can be developed within the complexity of the real world.

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Acknowledgements

We thank the German Academic Exchange Service (DAAD) and the German Cooperation

(GIZ) for funding a workshop on food security and biodiversity conservation, held at the

South Eastern Kenya University in July 2013. We thank two anonymous referees for critical

comments that improved this article significantly.

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Figure 1: Increase in the Kenyan human population from 1980 to 2012 in millions (solid line),

stagnation in yields of maize in tonnes ha-1 (dashed line), and the total production in tonnes

ha-1 (dotted line).

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Figure 2: Area and cotton-yield in Kitui-district, a semi-arid area in east Kenya. While the

area needed for the production of cotton strongly decreased (hatched shape), the yield

increased within the same time window (solid line), mainly by the application of fertilizer.

After an initial raise, yields dropped as rare nutrients became increasingly depleted. Data

taken from Jaetzold et al. (2012).

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Figure 3: Changes in climatic conditions and subsequent altitudinal shifts in agricultural use

between 1980 and 2007 in Eastern Kitui county. The total area of suitable agricultural land

(lower midland LM) decreased by 20%, the area of less suitable zones of agro-ecological

potential (especially the agroecological zone inner Lowland IL 5 & 6) increased by 20% since

1980. Increased aridity = shaded areas, decreased aridity = dotted areas. Data taken from

Jaetzold et al. (2006c).

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