ROBERTO FABRICIO Herald Columnist

Up the Mississippi River from New Orleans, in the shadow of the banyan trees of Baton Rouge, Lisandro Perez , a Cuban American from Miami, looks at our city from a unique perspective.

His mentality is at once Cuban and Southern.

Perez, 36, was born in Cuba, came to Miami as a teen-ager, graduated from the University of Miami and went on to the University of Florida, where he received a doctorate in sociology.

Last month, he was named acting dean of Louisiana State University's sociology department. He has lived with his wife and two children in Baton Rouge for 10 years.

In his cluttered office, he has accumulated an extraordinary amount of data on Cuban Americans. And, having spent nearly half his life at Gainesville and Baton Rouge, he knows the South.

"The most amazing thing that strikes me about Miami, as I look at it from a distance, is that there is such an intensity in the social interaction of the city," he said. "It is almost as if every single news story is of biblical transcendence."

Perez has his in-laws mail him the Miami newspapers every weekend. With the papers, he gets a special editing service.

"My mother-in-law circles in red all the stories that she feels are specially important," he told me. "Invariably they have to do with the East-West struggle and Cuban penetration in Central America."

erez sees the Cuban exodus to the United States and this country's growing Cuban community as part of a trend that began more than 100 years ago during Cuba's wars of independence from Spain.

"The relationship between the two countries is very special and has longstanding historical precedent," he said. "Just as there was a huge American presence in Cuba through the first half of this century, it was almost unavoidable that, given Cuba's proximity, the trend would reverse once the Cuban revolution took place."

Perez sees many traits common to the South and pre- revolutionary Cuba, among them the agrarian character of their economies and the similarities between the vestiges of slavery and those of colonialism.

It is ironic, he says, that with the many common traits and experiences of Southerners and Cubans, that there is such a gulf between them in South Florida. I agree.

hen you come to think of it, the Cubans in the United States have adjusted to their new host society faster than any comparable immigrant group in U.S. history. The similarities between Cuba and the South certainly had something to do with it.

Perez, who spends a month every summer living in South Florida, has a special kind of problem. He no longer feels at home anywhere.

"Baton Rouge is a very important part of my life because I have built a successful career here and I have come to love Louisiana, its people and its food," he said, smiling. "But with some regularity I get incredible pangs of nostalgia and I long for my Cuban roots that are so distant from here."

When he comes to Miami, he jumps right into the thick of the Cuban community where he grew up. For the next few weeks, he is busy with family and friends, absorbed by the cooking and the flavors. Then he gets a special kind of longing for the Deep South where he lives.

"I suppose that is the special problem of those of us who try to look at an exodus from a detached point of view, and then we become detached, perhaps too detached and suddenly there is no home, no real home to go back to. . . . "