The changing land-use pattern in the Valley is evident on the outskirts of Kathmandu and Lalitpur as more and more land is devoured by urban sprawl.

The remaining arable land is increasingly turned into clay mines to supply brick kilns. Farmers are leasing their land to these kilns, and in the process are losing the fertility of their topsoil. Degradation of land quality is a virtually irreversible process and the soil never gets back its fertility.

The 120 brick kilns in the Valley erode the topsoil completely, and what the farmer gets back at the end of the lease is a large pit devoid of any agricultural value. Brick kilns run mostly from December to June, and the farmer is paid the equivalent of a wheat harvest in the area being leased. Most brick kilns close down during the monsoon when the land reverts back to paddy cultivation.

At the Chun Devi Ita Bhatta in Bhaktapur, supervisor Shivshankar Yadav boasts that his kiln occupies 90 ropani of land and bakes five million bricks every season.

The farmer is compensated 160kg of wheat priced at Rs 11 per kg for every season his land is leased. What is not factored into the calculation is that in one year, the farmer will have lost 220cm of his priceless and irreplaceable topsoil.

Nir Kumar Shrestha, a farmer in Bhaisepati reckons he has lost nearly two metres of his topsoil in the past four years after he leased his field to the SK Chimney Bhatta. "My land had become useless for wheat, but after hauling loads of compost and manure, I manage to salvage the paddy," Nir Kumar says.

The farmer's traditional risk-averse nature is overruled by the promise of windfall gains, opening them and their soil to exploitation by the brick kiln owners. The cash in hand is too tempting, and many can't afford to think of the longterm consequences.

At Jhaukhel in Bhaktapur, 78-year-old Gyan Bahadur Suwal is ploughing his 5.5 ropani of land all by himself. For the past 12 years, he has been renting out his land to Jay Dibyaswori Ita Bhatta and his field is now four metres below the surrounding land. The kiln owners don't always level off the land before they leave, and even if they do it doesn't bring back the lost fertility.

Gyan Bahadur remembers when his land gave him 480kg of paddy with just organic fertiliser. Today, the same field produces only 180kg, and even this with lots of hard work hauling fertilisers. Gyan Bahadur has also seen his vegetable crop go down and his profit margin is now nil. It actually makes more sense to lease his land for Rs 3,500 for six months to the brick kiln owner. Almost everyone in Jhaukhel these days sells off their top soil to the brick business, and those who don't find their property sitting high and dry above the surrounding fields.

The relationship between environment and development in Kathmandu Valley is inverted and the environmental stresses are contributing to underdevelopment and poverty. One of the basic causes of poor land management is poverty, but its consequence is ever-deeping poverty. To get out of this vicious cycle, land use alternatives must be reconciled with demographic pressure. And this can only happen if the farmers have insurance against crop failure and other sustainable alternatives.