By Ayyanadar Arunachalam, ICAR-Central Agroforestry Research Institute, Jhansi, Uttar Pradesh
Plants are an important source for the sustenance of life on this planet. Among the plants, some plants are perennial, i.e. their vegetative and reproductive stage continues throughout the year. These ‘woody perennials’ include trees, palms, bamboo and shrubs. Yet, mostly woody perennials are referred to simply as trees.
The first woody perennials appeared on this planet about some 419.2-358.9 million years ago (Devonian Period) and they brought with them some major changes to the earth’s terrestrial ecosystem. Like the first woody perennials, even today the presence or absence of these woody perennials has an effect on the ecosystem at the micro and macro levels.
Globally, there are numerous movements and campaigns to encourage, promote and carry out tree planting. It is widely believed that a massive tree-planting programme can help mitigate climate change. Tree plantations—whether afforestation or reforestation—are recognized as one of the nature-based solutions that can contribute to climate action.
This begs the question: Why exactly are trees a good solution for mitigation and adaptation of climate change? In simple words, trees have the potential to sequester the greenhouse gas carbon-dioxide, a commonly known greenhouse gas most commonly cited for aggravating climate change.
Trees are a unique form among the plant kingdom not only for their structure but also for their functional attributes. Apart from the climate mitigation benefits, trees have been a source of food, fodder, fibre, fuel and fertilizer since time immemorial. The canopy created by trees sustains other plant forms below, hence protecting the uniqueness and health of the forest ecosystem. Every food crop cultivated today has been domesticated from forests and even today, forests have many more plants that can serve both as food and medicine. As per FAO report in 2018, 76 million tonnes of food derive from forests and marketing of non-timber forest products (NTFPs) is highly unregulated in many parts of globe. Thus, the values are an indicative factor of our dependence on forests. On other hand, intensive industrial agricultural practices have ensured food security at the cost of environmental security and utterly failed in ensuring nutritional security to the masses. In this regard, the inclusion of wood perennials in food production systems will be beneficial on multiple fronts for both urban and rural regions.
Woody Perennials in Urban Areas
Trees in the cities have social, cultural and ecological relevance. All kinds of tree-related events, such as planting or felling, are often discussed in public and reported by the media. While the contribution of urban trees in terms of carbon sequestration to help cope with global warming is minimal compared to natural forests, there is a need to encourage planting trees in cities as they do contribute to attaining three Sustainable Development Goals (SDGs): (i) human health and well-being (SDG 3), (ii) creating sustainable cities (SDG 11) and (iii) conservation of terrestrial ecosystems (SDG 15).
An increase in population has adversely affected the green cover in urban India—Chennai and Mumbai have a meagre 0.46 m2 and 0.12 m2 of green space per capita, respectively, as compared to the UN recommended standard of 9 m2 of green space per capita. Both Chennai and Mumbai are coastal cities where oceanic influence on weather mitigates the extreme heat. However, the situation is going to be worse in land-locked cities like Bengaluru and Hyderabad. Moreover, considering the air pollution levels and dust conditions, there is a need to increase the tree cover in the cities, and studies have systematically recorded the importance of trees in cities. One crucial matter will be the choice of tree species in urban areas—they should not only be selected to carbon sequestration, oxygen production or pollutant removal utility but preference should be given to the native species irrespective of the utility. Each tree is a hub of life as other living organisms are intertwined with it. The concept of wood wide web in old growth forests of Canada indicates the fungal and tree root network gives a hint on the role played by these perennials in an ecosystem. There many such intricate relationship between the perennial plant and other living being in a habitat. Thus, the native trees can support a greater share of living organisms as they are adapted to native trees
Woody perennials in Rural Areas
On a global scale, trees in rural areas do not share the same limelight they do in urban areas. However, in some South Asian countries and African countries, tree-based farming systems have been proven to improve livelihood and alleviate poverty. The World Agroforestry Centre (also known as ICRAF) has a special focal programme – Resilient Productivity and Profitability of Agricultural Systems with Trees. CGIAR has a dedicated CGIAR Research Programme on Forests, Trees and Agroforestry. All such programmes are a direct indication of the beneficial effect of trees on the farming community. Numerous research studies have documented the social benefit as well as the economic benefit of the inclusion of woody perennials in farmlands in India. The government of India also acknowledges the role of trees in farmlands in its policies and schemes; the National Agroforestry Policy (2014) is a dedicated policy that promotes trees in farmlands.
The definition for agroforestry in the 1970s was “Agroforestry is a collective name for land-use systems and technologies where woody perennials (trees, shrubs, palms, bamboos etc.) are deliberately used on the same land management unit as crops and/or animals, in some form of spatial arrangement or temporal sequence. In agroforestry systems, there are both ecological and economic interactions between the different components”. Subsequently, the definition of agroforestry was simplified and modified to highlight its contribution to the environment and natural resource management.
“Agroforestry is a dynamic, ecologically based, natural resource management system that, through the integration of trees on farms and in agricultural landscapes, diversifies and sustains production for increased social, economic and environmental benefits for land users at all levels”.
“Agroforestry, a combination of agriculture and forestry, is a land use that combines aspects of both, including the agricultural use of trees”(van Noordwijk, 2019). However, fundamentally, the difference was the usage of the word “trees” instead of “wood perennials”. This subsequently led to contextualizing agroforestry as a forestry-centric subject but on the contrary, it is more multidisciplinary.
As of the latest estimates done by the ICAR-Central Agroforestry Research Institute, the total area under agroforestry in India is 23.36 m ha and the extent of Trees Outside Forests (TOF) in India as reported in the 2019 ISFR is 29.38 million hectares. This gives a realistic comparison of the proportion of trees outside reserved forests in the country. It would not be an exaggeration to state that more than 90 % of TOF is contributed by agroforestry i.e. woody perennials in farmlands. Moreover, the Indian government’s goal of achieving 33% forest and tree cover for ensuring ecological security of the nation/country can be achieved only through upscaling of agroforestry. Only 46.19 m ha of land has been added to the total forest and tree cover since India’s independence, thus accounting for 24.56 % forest and tree cover in relation to the total geographical area of the country as of 2019. We therefore need more than 27.19 m ha land under forest and tree cover to be an ecological secure nation. In this context, upscaling agroforestry at the district level is a more prudent approach and the need of the hour.
This blog is part of the GFAR Partners in Action series, celebrating the achievements of our diverse network of partners who are working together to shape a new, sustainable future for agriculture and food. Each month we will be showcasing stories related to a key theme in agri-food research and innovation. The theme for November is Building resilience to climate shocks.
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