Today is the International Biodiversity Day 2008: Biodiversity and Agriculture

“In the process of domestication of plants for agricultural purposes, human beings have used about 7000 species, out of the 350,000 species of higher plants. According to Dr. Siril Wijesundera of the Department of National Botanic Gardens in Sri Lanka, about 200 plant species excluding the medicinal plants have been used for agricultural purposes. The country has a range of cereals such as maize, sorghum and other millets (Table 1). Among the pulses, which include cowpea, green gram, black gram, winged bean and soybean, only 30% have been characterized. Sri Lanka also has 8 indigenous species of Cinnamomum, about 700 known selections and 10 wild species of pepper, about 10 wild races of cardamom, several indigenous species of betel, 3 species of nutmeg, 2 species of chilli, 1 species each of ginger and turmeric, and 29 types of Musa spp. with different fruit characteristics.”
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by Prof. Buddhi Marambe , Dr. Pradeepa Silva , Dr. Gamini Pushpakumara


(May 22, Colombo, Sri Lanka Guardian) May 22nd was declared as the International Biodiversity Day (IBD) by the United Nations General Assembly met in December 2000 to commemorate the adoption of the text of the Convention on Biological Diversity (CBD) and to increase the understanding and awareness of biodiversity issues. Since 2002, the IBD has been celebrated under the thematic areas of global relevance, as given below.

In year 2008, the IBD is celebrated under the main theme "Biodiversity and Agriculture", at a time that the significance of agriculture has never been felt in the recent past at present levels, and that the whole world is pressed for ensuring food security. Thinking in terms of agriculture, biodiversity is the (a) basis for the sustainability, productivity and resilience of agricultural systems, (b) foundation of ecosystem services essential to agriculture and human well being and (c) origin of all crops and domesticated livestock (species) and the variation within them (genes).

Human intervention converts the natural ecosystems to agricultural ecosystems, to provide much needed food for ever growing population. Agriculture is a classic example of how human activities have intense impacts on the ecosystems of our planet. At the beginning of civilization, human beings domesticated plants and animals selecting species/breeds from a rich diversity of wild species to facilitate agriculture. With a continuing process of human involvement, we have modified the diversity of domesticated species, landscapes and environments. As a result, under present day context, 25% of the Earths’ land surface is covered by cultivated systems. The major land use sectors in Sri Lanka are agriculture, forestry, wildlife and animal husbandry. The land use statistics indicates that of total land area, 25 per cent is under permanent agriculture, 20 per cent is under sparsely used crop lands, 12 per cent is under homesteads, 16 per cent under grasslands, marshes, etc, and 23 per cent under forests.

In the process of domestication of plants for agricultural purposes, human beings have used about 7000 species, out of the 350,000 species of higher plants. According to Dr. Siril Wijesundera of the Department of National Botanic Gardens in Sri Lanka, about 200 plant species excluding the medicinal plants have been used for agricultural purposes. The country has a range of cereals such as maize, sorghum and other millets (Table 1). Among the pulses, which include cowpea, green gram, black gram, winged bean and soybean, only 30% have been characterized. Sri Lanka also has 8 indigenous species of Cinnamomum, about 700 known selections and 10 wild species of pepper, about 10 wild races of cardamom, several indigenous species of betel, 3 species of nutmeg, 2 species of chilli, 1 species each of ginger and turmeric, and 29 types of Musa spp. with different fruit characteristics. The medicinal plants in Sri Lanka include about 1414 species. Among them 50 species are heavily used, 208 are commonly used, and 79 are threatened species. The ever increasing demand for food compels us to develop high yielding crop varieties with tolerance to biotic and abiotic factors of the production environment. This can be made possible only if there is sufficient genetic diversity. However, today at a global scale, we rely only on 30 crop species to provide an estimated 90% of the world population’s dietary requirements, signifying the risk involved in ensuring food security and lack of sense or ignorance in effective utilization of the rich diversity available on this planet.


The situation regarding the livestock sector is not different to that of the crop sector. Out of the estimated 15,000 species of mammals and birds found globally, only 30 to 40 have been domesticated for food production and the world relies on 14 species, including cattle, goats, sheep, buffalo and chickens, to provide 90% of global livestock production. In Sri Lanka, only 6 mammalian species and 7 avian species have been used for livestock production. The breeds available in Sri Lanka and used for livestock production under each category are shown in Table 2. In the global scenario, making the conditions grave, the FAO statistics revealed that there is an genetic erosion in the livestock breeds at an alarming level where in the past 6 years, a breed has been lost from the ecosystems each month. At present the threat of extinction is about 5-6 breeds a month. In Asia, the breeds under extinction or risk, is 14 per cent.


The human interventions in converting natural ecosystems to agricultural ecosystems have contributed immensely to the world’s food production. During the later part of the 20th century, the food production has tripled where the population has doubled. However, the present crisis faced by the scientists and producers is that the crops grown have reached their genetic potential with marginal increase in productivity under optimum management, while the world population grows at a remarkable rate. It is expected that the world’s population would reach 9 billion in 2050, a 50% increase from what it is now, 90% of the growth of population is expected in developing countries, food consumption demand (crop based food) will increase globally by 50%, and meat and animal products demand will also increase globally by 50% (especially with rising income levels), food insecurity would lead to widespread hunger and malnutrition creating conditions abject poverty, disease epidemics and even food riots as we experience now in some countries in the sub-Saharan Africa. In such a situation, the grains, legumes and fruits produced are a testament to the ability of farmers to obtain nutritious food from ecosystems. The foundation for success of such an endeavour is Biodiversity. However, one of the most important challenges to feed a growing population is with the combined impacts of climate change and the unprecedented loss of biodiversity.

We have altered ecosystems more rapidly and extensively. It is estimated that 60% of the ecosystem services namely, (a) regulation of pests and diseases, (b) nutrient cycling, such as decomposition of organic matter, (c) nutrient sequestration and conversion, as in Nitrogen-fixing bacteria, (d) regulating soil organic matter and soil water retention, (e) maintenance of soil fertility and biota, and (f) pollination by bees and other wildlife, have been lost due to adverse impacts on the ecosystems imposed by human beings. All life forms rely on these ecosystem services. Despite the many good things agriculture has done to the communities, in 1990s, 20% of CO2 emissions have originated from land use changes, mostly deforestation to commence agricultural activities, since 1960s the water withdrawals from lakes and rivers has doubled with 70% of water used for agriculture worldwide, since 1960 the flows of nitrogen in ecosystems have doubled and flows of phosphorus have tripled, and the soil is being lost at a rate of 13 - 18 times faster than it is being formed. The use of biodiversity for prosperity through Agriculture has to be considered in this context.

Sri Lanka has been identified as one of the most biologically diverse countries in Asia with remarkably high proportion of endemism among its fauna and flora. The natural forests harbor many wild relatives of crop plants, medicinal plants and horticultural plants, and animals. In Sri Lanka, the ecosystem variations have been studied in a relatively detailed manner, however, more work remains to be done with regard the species diversity to ensure their conservation and sustainable use. Better use of biodiversity is an essential component of the response necessary to meet the challenge of ever growing population. Since hunger can only be overcome if increased food production and poverty alleviation proceed in parallel, new crop varieties and livestock breeds must also be developed meet the needs of the humans. The genetic diversity within species needs to be adequately studied and documented.

Sri Lanka exhibits a wide range of topographic, climatic, edaphic and hydrological variation. The long history of agriculture in the country, and farmers’ selection and cultivation/husbandry of plant and animal species since time immemorial, and the traditional farming practices to suit the diverse agricultural ecosystems have all contributed to a rich agricultural biodiversity. However, the sustainable use of this rich biodiversity has been an issue. We all have a role play in supporting functional ecosystems, diversity in species and genetic resources, to sustain life everywhere. It may be too late to reverse the damage the planet has suffered in terms of loss of biodiversity, but it is never too late to start preserving what is left at present.

This year’s International Biodiversity Day seeks to highlight the importance of sustainable agriculture to preserve biodiversity, to be able to feed the world, to maintain agricultural livelihoods, and to enhance human well-being into the 21st century and beyond. Joining hands with the world, the Ministry of Environment and Natural Resources, held the International Biodiversity Day activities on 16th May 2008, where an "Action Plan for Agrobiodiversity" was launched. This is a significant achievement in Sri Lankan context, as it is a highly opportune time that we all get-together, revitalize the importance of using the biodiversity of our agricultural ecosystems in a sustainable manner, and to move away from the loosing strategy of using few species and breeds to meet our food security.
Note:
The authors are the Dean, Senior Lecturer in Animal Genetics, and Senior Lecturer in Agroforestry, respectively, of the Faculty of Agriculture, University of Peradeniya
2002 Forest Biodiversity
2003 Biodiversity and Poverty Alleviation – Challenges for Sustainable Development
2004 Biodiversity – Food, Water and Health for all
2005 Biodiversity – Life Insurance for our Changing World
2006 Protect Biodiversity in Drylands
2007 Biodiversity and Climate Change
- Sri Lanka Guardian