Among the images that Sunday supplements start publishing to sum up 2010, I suspect there will be one missing. One that, for me, sums up a year of continued and frightening environmental degradation and the looming prospect of severe food shortages in years to come. It is the image of workers in the Maoxian county of Sichuan, China, an area that has lost its pollinators through the indiscriminate use of pesticides and the over-harvesting of its honey. These workers aren't picking fruit, or digging, or planting. They're pollinating pear and apple trees by hand. In this part of China, the honeybee has been replaced by the human bee.

I learned about this startling practice this year, but in fact its been going on for the past two decades. Every spring, thousands of villagers climb through fruit trees hand-pollinating blossoms by dipping "pollination sticks" (brushes made of chicken feathers and cigarette filters) into plastic bottles of pollen and then touching them against each of the tree's billions of blossoms.

One-third of all our food staples only grow after pollination. In the United States alone, the cost of replacing this "free service" which nature has provided for hundreds of thousands of years, is put at anything between £14bn and £92bn. And that's in one country alone. If we don't wake up to the global crisis facing our pollinators, the banking crisis is going to look relatively trivial as the world runs out of food. China can, for the time being, afford to hurl this level of human labour at the problem: but short of the prospect of actual starvation, it is wholly unrealistic to imagine this happening in, say, California, where bees still pollinate orange, apple, pear and plum trees.

Here in Britain we are losing bees at an alarming rate. Worldwide, many beekeepers estimate that, at the current rate of bee loss, there now may be only a 10-year window to find a cause and a solution to this problem. And the British Beekeepers Association has warned that honeybees could disappear entirely from the UK by 2018.

People may think that bees play no part in city life. Not true. When Boris Johnson launched Capital Growth two years ago, with the aim of creating 2012 new food-growing spaces by 2012, none of us realised just what an enthusiastic response we would get from communities across the capital. We now have 700 new vegetable gardens and are well on target to create another 1,300 by the end of 2012. Some are on roofs, some in parks, some on estates, in school yards, in deserted and neglected spaces on building sites. A few of the projects are planting orchards as well as vegetables. One street I visited recently is planting a communal orchard – each house is growing two or three different trees and the results will be shared by everyone. We need the bees, and indeed, London produces fantastic honey as bees forage across a very broad range of plants, both native and exotic.

No one quite knows why the honeybees are collapsing in numbers so dramatically but the over-use of pesticides on farms and in gardens, the mysterious "colony collapse disorder", the spread of disease like the varroa mite or foul brood, the changing climate and an increase in mono-cropping on farms, which means less food for bees throughout the summer season are all playing their part.

When I was a child, I used to help my father keep his three hives, donning my gloves, veil, hat and coat in the autumn to help bring in the honey. We often used to find wild hives in the countryside, the swarm clinging to a branch. By putting a box underneath them, and then lifting it up at the same time as banging lightly on the holding branch, we'd capture the swarm and let it out by an empty hive. Our bee colony steadily grew in size. But that's a childhood pleasure I suspect very few enjoy today.

According to Defra, beekeeping is pursued by 200-300 commercial bee farmers who depend on beekeeping for all or part of their income, but it is dominated by 33,000 amateur beekeepers who pursue the craft for personal interest. Without specialist support their investment in the required measures to promote or manage bee health or to collaborate to address common problems is likely to be limited. And this is where Capital Bee, the initiative launched today by the mayor and I, as a logical and practical next step to Capital Growth, comes in.

People don't need to own hives – they can plant bee-friendly plants and flowers even in small spaces such as window boxes. We can also simply learn to love bees in the knowledge they are making an important contribution to our towns' and cities' ecological health.

Einstein said if bees were to disappear from the surface of the earth humanity would have no more than four years to live – whereas if we were to disappear, the rest of the planet would carry on just fine.