Complex sentence: He studied the effects of sewage outfalls and El Niño on kelp forests, the predations of sea urchins, and consulting for California's kelp-harvesting industry.
Split into simpler sentences: He studied the effects of sewage outfalls and El Niño on kelp forests, and the predation kelp by of sea urchins. He served as a consultant for California's kelp-harvesting industry.