2 Much of this land, rare though it is, is being permanently taken out ofagricultural use by being built upon. Between 1960 and 1971 Japan lost more than7 per cent of its agricultural land to buildings and roads and European countrieslost from 1.5 per cent (Norway) to almost 4.5 per cent (Netherlands). Between1961 and 1971 more than 8000 square kilometres (over 2 million acres) of
3 The impact of these losses will be felt by millions of people far away from thecountries in which they are occurring. As Gus Speth, chairman of the US Councilon Environmental Quality. says of the US losses: 'When you figure that we've gotabout 400 million acres (1.6 million square kilometres) under cultivation, and we'refeeding about 300 million people, counting our exports, it means that every timewe lose a couple million acres of cropland that's a million people that aren't goingto be fed.' The impact will not just be confined to the food sector. In 1979 theUSA earned $33,000 million from agricultural exports, enough to make up half thecost of the country's oil imports.
4 Not only is farmland disappearing at an alarming rate, but much that remainsis being heavily degraded by bad farming practices. As much as one-third of theworld's cropland will be destroyed in the next 20 years if current rates of landdegradation continue.
5 Agricultural productivity depends not only on maintaining soil quality butalso on adopting cropping patterns and retaining a variety of habitats to encouragebeneficial insects and other animals. These are important for the pollination ofcertain crops and for helping to suppress pests, as part of integrated programmesof pest control. Pests can no longer be controlled by heavy doses of pesticides,partly because of the rising cost of petroleum- derived products but largelybecause excessive pesticide use promotes resistance (the number of pesticide resistantinsects and mites has doubled in 12 years), destroys natural enemies, turnsformerly harmless species into pests and contaminates food and feed. Insteadpesticides should be used to supplement a battery of methods integrated inappropriate combinations. These methods include the introduction of pest- resistantcrop varieties, special planting combinations and patterns, mechanical methods, theuse of repellents and hormones, and the encouragement of natural enemies.
6 Permanent pastures (land used for five years or more for herbaceous foragecrops, whether cultivated or wild) are the most extensive land- use type in theworld, occupying 30 million square kilometres (12 million square miles), or 20 percent of the earth's land surface. Permanent pastures and other grazing land areusually unsuitable for crops without intensive capital investment. Theirproductivity is generally low, ranging from 1 hectare (2.45 acres) supporting threeto five animal units on fertile, well-managed pastures in central Europe to 50-60hectares (120-150 acres) to support one animal unit in Saudi Arabia. Nonetheless,grazing lands and forage support most of the world's 3000 million head ofdomesticated grazing animals, and hence most of the world's production of meatand milk.
7 The genetic material contained in the domesticated varieties of crop plants,trees, livestock and aquatic animals, as well as in their wild relatives, is essentialfor the breeding programmes in which continued improvements in yields,quality, flavour, durability, pest and disease resistance, responsivenessto different soils and climates, and other qualities are achieved. These qualities arerarely, if ever, permanent. For example, the average lifetime of wheat and othercereal varieties in Europe and North America is only five to fifteen years. Pests anddiseases evolve new strains and overcome resistance; climates alter; soils vary;consumer demands change. Farmers and other crop producers, therefore, cannotdo without the reservoir of still-evolving possibilities available in the range ofvarieties of crop and domesticated animals, and their wild relatives

- Give precedence to farming. Prime farmland is taken over by buildings androads because towns tend to grow up in the middle of agricultural land andtheir expansion is poorly controlled, and because property values are muchhigher than agricultural values. Farmland near Washington DC, would sellfor almost $40,000 per hectare ($15,000 per acre) to a suburban developer.

But for a farmer to earn an equivalent return from that land, he would haveto charge $12 for every bushel (35 litres) of corn, about four times the going rate. If conversion of land to non- agricultural users is left to the unregulatedmarketplace, the best farmland will continue to disappear quickly.

Therefore, governments should first of all make a decision to giveprecedence to agriculture whenever there is competition betweenagriculture and other uses for high quality land. They can enforce thatdecision by prohibiting the sale of farmland, dropping governmentassistance for projects that would encourage conversion of farmland, andpromoting the use of lower quality land as sites for urban development.

- Start a top-level soil conservation service. Land users allow the land todegrade because they are after a quick buck, they do not know better, orthey have no choice. With the costs of seeds, fertilizers, pesticides andequipment going up, with credit either short or expensive, and with marketprices for produce uncertain, farmers are often tempted to wring more outof the land than it can sustain. They may neglect drainage, grow cropswhere grass alone is suitable, or convert to grass land that should remainwooded. Many farmers are simply unaware of the effects their actions thisyear will have on their capacity to grow food in future years. Or, if they arevaguely aware, they do not know what to do to make sure that anyincrease in productivity is sustainable. Millions of peasant farmers,especially in developing countries, are not in a position to conserve the soil,however knowledgeable they may be.

- Step up programmes to preserve crop and livestock genetic resources. Thethree ways of preserving the genetic diversity of the world's vanishingspecies and varieties are outlined below.

(a) On site—in which the stock is preserved by protecting the ecosystemin which it occurs naturally.

(b) Off site, part of the organism—in which the seed, semen or otherelement from which the organism concerned can be reproduced ispreserved.

(c) Off site, whole animal—in which a stock of individuals of theorganism concerned is kept outside their natural habitat in a plantation,botanical garden, zoo, aquarium or ranch.