Sunday, June 1, 2014

Ecosystem Sciences Part 2 - The Gifts of Earth

In the first part, we heard that ecosystem provides us with various services that are extremely valuable. Ecologists have classified the services into five types. We start with the first type- Provisioning.
Provisioning is the most easily understood kind of ecosystem services. The ecosystem provides us with lot of goods- such as food, water, clothing, medicines and so on. Take fish, for example. The worldwide production of fish is worth about 200 billion dollars. 20% of the world population is dependent on fish as their primary source of proteins. Seafood is not just for us humans, but our pets also eat food that majorly contains fish.
Grasslands are the source of food for our animals like sheep, cattle, horses, asses and camels. Some of these animals provide labour- such as horses and mules. Many provide useful products like meat, milk and wool. Take the cattle for instance. There are about 1.5 billion cattle in the world today, one for nearly five human beings. About 27% of the world’s land is dedicated to cattle. In 2007, 65 million tons of beef was eaten by the people of the world. The beef and dairy industry is worth more than 200 billion dollars. The livelihoods of millions of people are dependent upon these animals that are fed by the grasslands.
Natural ecosystems in forest lands and woods provide goods like fuel. About 15% of the world is dependent on natural wood to provide energy. In some parts of the word, the dependence on wild wood as fuel is as high as 40%. Apart from wood we use many forest products like fruits, nuts, honey, mushroom, fiber, spices and so on. The value of such goods is difficult to estimate, but is definitely huge.
Croplands provide us a large part of our food including the grains, oils and vegetables. Similarly they also supply us with clothing like cotton and linen and also fulfill our vices like tobacco and wine. But croplands should be considered as human activity. They do not occur naturally. Human beings started agricultural activity about ten thousand years ago, instead of depending on nature for food like other animals. Ecosystem services continue to play irreplaceable part in agriculture, as we will see in later parts. But right now, lets consider a property of nature without which agriculture wouldn't have been possible – biodiversity.
Biodiversity simply means that there are so many varieties of living beings in nature. You take any particular specie of grass, and there will be many varieties similar to it in the wild. Even in the same specie, every individual is different from another, due to genetic variation. This fact helped the development of agriculture. The ancestor of apple in nature did not produce the large and juicy fruits that we eat today. They were much smaller in size and not that delicious. But there were a lot of varieties of pro-apples in nature. Our ancestor chose the variety that he thought was best for consumption and planted sampling of that breed. When the next generation of apples grew, he again selected the best sample. This process, called Artificial Selection, created all the agricultural products that we eat today, like the big apples and long ears of corn.
(See my earlier post on the subject of Artificial Selection -

The root of this development were in the biodiversity. The same biodiversity continues to help us in creating new foods. If we want to create new crops that are more productive, resistant to pests or need less water, we must turn to nature once again. Natural habitats are a storehouse of a vast array of varieties of vegetation, from where our next superfood might come.
We currently cultivate only about 100 species of plants that supply bulk of our food requirements. But there are more than 70,000 plant species that can be used as food. Some of these may be more suitable for us than the current crops. More and more of our usable land is getting salinized (salty) and droughts are becoming a frequent occurrence because of climate change. In this situation, our current crops may not serve us well. We might need different crops that can withstand these difficult conditions and fulfill our growing need for food. Biodiversity is the only resort if this happens.
The advances in biotechnology can certainly help in creating new foods, by combining the characteristics of more than one specie. But the biodiversity itself must remain. The variety cannot be conserved by protecting a few individuals in zoos or botanical gardens. There must be enough population of each specie in its natural habitat to provide the variation. So the next time we hear of a piece of natural ecosystem being lost to development, we must remind ourselves that we may have lost some variety of grass that could have become our next rice or wheat.
In the next part, we continue with Provisioning Services that give us our medicines.

No comments:

Post a Comment