Very still, this square: night stillness, with a halo of light emanating from behind an erect trio of cigarillo-slender smokestacks. Two bristling tangles of pipes and lights, and then at dead center, that familiar monumental pair of bulbous stogies spout a plume upwards to scuff the otherwise pristine halo of fog-evened sky, then reproduce themselves downward toward their reflection in the flat water that is Elkhorn Slough.

“Moss Landing Power Station” is one of a portfolio of 30 important photographs that resulted from a 1987 California Arts Council grant for an Art in Public Places project that brought English-born Michael Kenna, a landscape photographer who already was known worldwide, to work with the Elkhorn Slough Foundation.

On April 4, the foundation celebrated its 25th anniversary and the 20th anniversary of Kenna’s work that it published in a small book now much prized and out of print, The Elkhorn Slough and Moss Landing: Photographs by Michael Kenna. These photographs are now exhibited at Monterey Museum of Art, where the foundation presented the gelatin silver prints along with several donated by the artist, to the museum’s permanent collection. “This is where art and science meet,” says Mark Silberstein, foundation executive director.

He repeated the phrase the morning of April 5, as he and Kenna revisited the sites of many of Kenna’s extraordinary images in the company of about 15 photographers, naturalists and art collectors. Silberstein spoke of “historical ecology,” an emerging discipline that, along with other data, uses photographs and paintings to document decades of changing habitat. (In this most painted and photographed bay, he could gather a detailed recording of the life of most every creek, boulder and tree on the coast.)

From the first promontory overlooking the expanse of ponds, grassy spits and small islands that form the slough, it was clear that the PG&E Power Plant that seemed so fixed a part of the landscape in Kenna’s photographs now has been modernized and streamlined, though its familiar duo of steaming stogies remain. This industrial monolith acts as symbol for one of the most delicate, plentiful and diverse ecosystems on the planet. Into the last habitat of red-legged frogs, into warm lagoons where leopard sharks swim from the bay to give birth, where cranes and herons nest in tall stands of trees at water’s edge and where the deepest ocean canyon in the Americas empties hundreds of species into its mouth, each day more than 1 billion gallons of water cycle through the power plant and into the estuary, making the plant a significant part of the ecosystem.

In this place where art and science meet, so does intensive farming and transportation, housing developments and a busy railroad track that cuts through the wildlife preserve.

Kenna is excited by such meeting points. Documentation is the humblest function of his photographs; their highest might be called a crystallization of insight. Using an old Hasselblad, a 2-by-2-inch negative and a simple darkroom setup, the artist has developed an unmistakable signature in compositions as compelling in form as they are bulging with content. The photographer looking out is present in every composition: the reverence for what he sees, the point of view he sees from. He often assumes extreme perspectives to line up a series against a contrasting background, frames objects into wide-angled relationships with each other, or isolates one element against an atmospheric background. Kenna’s works can be appreciated purely for their formal drama and simplicity, calling to mind tonalists, colorists and minimalists but belonging to none of these, for he is first and most certainly a black-and-white photographer.

His photographs are neither taken, nor captured, nor shot. Rather, they are acts of patient exchange. Kenna spends time. He often camps out to gather long exposures and the night shots for which he is well known, preferring to work in the hours of late evening through early morning. Stillness, softness, mist. “Another half hour and this would have been completely different,” he says of “Brine Shrimp Boat, Moss Landing.”

The composition is exquisitely satisfying even as an abstraction. A seamless blanket of fog settle above the level shadow of the horizon. Below, a broad swath of breathlessly flat water is made to seem turgid, full, by the glittering fringe of wet pebbles that mark its waveless shoreline in the foreground, leaving the dark of the shore comfortingly at the bottom of the page. Breaking the hush of these horizontal tonal elements is a crusted quadrangle of planks, frozen on the flat water, aimed toward the horizon. A pole listing from its topmost angle is the only vertical element in the piece. The simplicity and glowing portent of a Rothko is here in monochrome.

ELKHORN SLOUGH: PHOTOGRAPHS BY MICHAEL KENNA continues through July 13 at Monterey Museum of Art, 559 Pacific St., Monterey. 372-5477 or montereyart.org. Contact the Elkhorn Slough Foundation at 728-5939 or at elkhornslough.org. Or visit the reserve at 1700 Elkhorn Rd., Watsonville. 728-2822.