Aug 8, 2023 · Two years of research were carried out to evaluate the effects of various sewage sludge and nitrogen doses on the turf performance of perennial ryegrass (Lolium perenne L.) under Mediterranean-type climatic conditions. Four nitrogen sources (NS) [NS1: ammonium nitrate (26%), NS2: Bursa City’s wastewater treatment plant’s waste, NS3: biogas production plant reactor waste, and NS4: food