What the Waves Take Away : MEMOIR : HEAVEN’S COAST,<i> By Mark Doty (HarperCollins: $24; 305 pp.)</i>

I can imagine the moment before he dies,” confided a friend of mine whose lover languished in the last stages of AIDS. “I can even imagine the moment of his death. What I can’t imagine is the moment afterward.” This vast and seemingly uninhabitable “afterward” is the territory charted by Mark Doty in his powerful memoir, “Heaven’s Coast.”

Doty’s story is catapulted into motion by the results of an HIV test; the author tests negative and Wally Roberts, his lover of 12 years, positive. The terror and injustice of this sudden rupture takes an immediate physical toll on Doty, whose lower back is wrenched out of alignment, leaving him with the apprehension that he will be unable to bear the weight of this new knowledge, unable to impel his body onward. A New Age physical therapist tells the author that the vertebra giving him the most discomfort represents “faith in the future.” What ensues is the story of a man who must renegotiate his belief in the future, who must regain the narrative continuity of his life, a life upon which AIDS will impose its grim revision.

“The world doesn’t need us to continue,” writes Doty in his prologue, “although it does need us to attend, to study, to name.” Consolation is possible for the author largely through the act of observing and articulating the particulars of nature, specifically the salt marsh and coastline of his Cape Cod home.

Doty, one of the country’s foremost poets, ruminates on flora and fauna with a care and acuity that makes his environment palpable, a complex presence that can both inspire and overwhelm. He describes the “bronzy, barbaric-looking claw of beach pea unfurling, and the bee-pestered wedding lace of beach plum.” Of Herring Cove he writes, “It is a whole shifting confluence of aspects . . . a continuous apocalypse; Sahara becomes sea becomes sand again, in a theater of furious mutability.” But the furious mutability of nature, and our lack of control over it, lead the writer to acknowledge that, often, the only antidote to despair is to feel despair more keenly. “Sometimes, all that helps,” he writes, “is a deep, bracing breath of emptiness.”

Almost immediately, sections of the memoir begin to leap forward and back in time--Wally’s decline is imminent or glanced at in retrospect. This jumbled chronology intensifies the mood of crisis and uncertainty, of one’s universe being, by turns, demolished and reconstructed. All the while, the piecemeal indignities of Wally’s illness, as well as the deaths of other friends (most notably the poet Lynda Hull), are accompanied by visitations from the natural world. Seals appear on the shore, cast their gaze toward the author, then vanish into the water like souls into an afterlife. The author’s dogs scout the beach, coming upon the remains of a dolphin. “Walking on the shore,” Doty laments, “what do I stand on but the vast, accumulated evidence of death? What do I confront, day after day, but death and death?”

Doty’s voice, driven by a restless, elegiac impulse, veers between reflexive praise and plain hurt, and finds the right notes for both. Often he locates an equipoise between the two emotions: Describing the viral brain infection that eventually claimed Wally’s life, Doty asks, “Was it a kind, compensatory mechanism of the disease, that took his nervous system’s ability to control his legs away, but gave him childlike pleasure in return, allowed him to keep his delight in the world?”

As Doty’s grief over Wally’s death intensifies, so does the pain in his back. The only way out of this pain, the author concludes, is through it. And so begins “Through,” the last and more harrowing half of the book. Here again Doty acts upon his imperative “to attend, to study, to name”; he turns the focus of his craft, unflinchingly, toward his lover. “That face. The pure self which looks out into the world. . . . Self-consciousness, doubt, circumstances, even history stripped away, he’s that awareness, that quality which is most essentially Wally.” In this section, a passage about, say, Wally’s craving for an ornately shaped licorice candy is followed by a graphic account of tending to him during his bouts of uncontrollable diarrhea. Ostensibly disparate aspects of physical being are treated with equanimity; appetite and excrement--the lover’s body is raised, as it were, by the survivor’s enduring regard.

Recollection--in the literal sense of gathering broken pieces--is the engine that powers many literary memoirs, and yet what makes this memoir exceptionally touching is that one can detect, beneath Mark Doty’s burnished prose, the heat and urgency of his task. In page after page, the process of finding words to embody the unbearable is, for author and reader alike, a “coming to terms.” And yet this book is far from a private exercise in catharsis. Doty escapes solipsism by way of his reverence for nature, by embracing fates besides his own and Wally’s, and by his ability to seamlessly introduce broad-ranging observations about domesticity, fidelity and even clothing, into his narrative. And always, his exacting, sensuous language resonates far beyond, as well as deeply into, the personal sphere.

The exigencies of this book have resulted in some fragmented patches of text. Chapters were written, the introduction explains, both during and after Wally’s illness and death. Although Doty uses the brilliant device of beginning a new section with a phrase from the preceding section, thereby accentuating the human drive for “ongoingness,” the final section, “Consolations,” is unapologetically collaged from friends’ letters, literary excerpts, Doty’s journal entries and records of his dreams. How else, except with tentative, borrowed strength, can one grapple with the indifference of death? How else, except with a kind of ragged grace, can one accept the loss of his beloved and construct a future alone?

* Reviewer BERNARD COOPER will participate, along with AMY TAN, in a writers’ discussion at the Los Angeles Times Book Festival on Sunday, April 21, at 3 p.m.