Atop a heap of old paper bags and plastic, a pregnant woman lay quietly moaning with pain from an evil-looking abscess on her leg. A small, mud-covered child sat in the dirt beside her, its head shinny with bald patches caused by malnutrition and disease.

Five months ago, the Nicaraguan national guard evicted them along with dozens of other peasant families from their seaside village 50 miles from here.

Today the families live in huts made literally, of rubbish - a few boards and sheets of plastic bound together with string - in an empty railroad yard on the edge of this small city in northwestern Nicaragua.

The peasants, and their sympathizers here and abroad, have protested their treatment to the Nicaraguan government and to U.S. officials who have expressed an interest in human rights. They expect little assistance from either.

It was the Nicaraguan government of President Anastasio Somoza that threw out, the peasants believe, and activists tell them it is the United States, through its economic and military assistance, that provides the "moral force" that backs oppression here.

The stories the Chinandega refugees tell of greedy landlords and generations of oppression are as old as the smouldering volcanoes that dominate the tropical landscape. The political and economic realities of their situation, they freely admit, are complicated far beyond their understanding.

The peasants blame their eviction on "white gold fever" - the desire of Nicaragua's large landholders to acquire still more acreage on which to grow the high-priced, long-fibre cotton that is the country's chief export crop.

Their village was built on what they thought was publicly owned property, given to them under an abortive land reform scheme begun two decades ago. The Nicaraguan government now says that the land is private, and that the landlords have registered their ownership papers with local authorities.

The soldiers came to their village unannounced, loaded the peasants on trucks with a few of their possessions, and dumped them in the rail yard. Left behind were their homes, their school, their fishing boats and the crops they had planted in the fields.

Since then, the peasants said, the government has provided them with no assistance, except the menacing nighttime presence of armed national guard troops who oaccasionally prowl the outskirts of their encampment.

These refugees are totally without income except for the occassional $1.70 a day a few of the men earn picking and cleaning cotton on the large plantations surrounding the city.

Local and international human rights groups charge that these families are amonging thousands of peasants who have been uprooted from their homes by the national guard, Nicaragua's only armed military and police force, on orders from the handful of wealthy families who own more than 50 per cent of the country's cultivated land.

Earlier this year, Julio Molina, an opposition member of the Nicaraguan House of Deputies, traveled to the United States to talk about this problem with American Civil Rights Activists. He said he discussed the possibility of non-violent opposition to the Nicaraguan government in meetings with both Coretta King, the widow of Martin Luther King Jr., and Cesar Chavez, the California farm labor leader.

"We want to struggle through strikes, through not paying taxes and not picking the crops," Molina said in an interview. "We are fighting with ideas, and have no resources other than ourselves."

The peasants, he said, "can't fight what the United States gives (Somoza) in weapons and aid."

The U.S.-donated weapons were used last week to put down a brief revolt, led by leftist guerrillas, in which at least 35 persons were killed.

The one thing all Nicaraguans, pro- and anti-Somoza, have in common is a healthy respect for the power and influence of the United States.

While most other Central and South American nations long ago lost their awe of the "Yanquis," the U.S. presence here has continued to dominate the Nicaraguan view of politics. American economic aid is a major factor here. The national guard continues to be supplied, as it has been since it was formed in 1933, with U.S. weapons, and its officers are trained exclusively at U.S. bases.

To the Nicaraguan government, this relationship with the United States demonstrates continued American support for the strident anti-communism that is still Somoza's guiding political principle. To the peasants and to the political opposition, it means that Somoza is still in power after more than 40 years of family rule, because the United States wants him to be.

Although they take some encouragement from the current U.S. human rights campaign - and the increasingly close calls Somoza has had in the U.S. Congress, where critics of his regime have been urging a halt to all aid - there is little hope here that things will soon change.

"I know that Carter has good intentions," Molina said, "but above all, he's a North American. A North American politician. "We are a small country, and talking against the dictator suits U.S. purposes right now. But it means nothing here."

The peasants are used to seeing the trucks and material the U.S. government sends here, said one peasant leader. They know that when a sign goes up saying a road or building is a "gift of the government and the people of the United States of America," it means nothing for them.

What the peasants want, Molina said, are "free elections. That is the best gift the United States could give us."

For now, Molina is trying to organize the displaced farmers and fishermen. Several days each week, he travels from the capital, Managua, 100 miles to the south, to the refugee villages around Chinandega. There he talks about "passive resistance," and writes down the names of those who have been jailed by the national guard in its seemingly endless effort to get the peasants to give up for good and move east.

Yet, talk in the encampment is increasingly of confrontation. "We are going back to our village, to our land," said 53-year-old Edurado Guardado, the unofficial spokesman in the Chinandega railroad yard. "We have no place else to go, and nothing else to lose.We have lived there all of our lives."

So far, the peasants campaign has not moved much beyond nighttime meetings at which they quietly strum guitars and sing songs they have written to the beat of protest. The songs, like those of a hundred such struggles that have come and gone in Latin America, speak of unity, of throwing off the landlords - and of an end to suffering.