Elemental Flow And Ecological Footprint Of Penaeus Vannamei Industrial Chain In Guangdong Province

Penaeus vannamei（common name for the white-leg shrimp）is a species with the largest production of farming shrimps in the world,in which the production of P.vannamei in China accounted for more than one third.The development P.vannamei industry are related to its resource input and environmental impact,but it still lacks comprehensive and detailed research data.In this paper,P.vannamei industry material cycle,ecological footprint,and the ecological costs of protein production in Guangdong Province of China,the one of major producing region of P.vannamei in the world,were carried out by using field investigation,laboratory experiments,and mathematical modeling,with the aim to study the industry resource management,environmental protection,protein supply analysis of P.vannamei industry.The results showed that to product 1 ton of P.vannamei,about 790.97 kg of carbon,132.58kg of nitrogen and 27.34 kg of phosphorus from Shandong,Hubei,Anhui,Jiangsu,Zhejiang in China,Myanmar,the United States,Brazil,Argentina,and other areas were transported to the coast of Guangdong Province;about 669.77 kg of carbon,98.3 kg of nitrogen and 24 kg of phosphorus of pollutants,e.g.uneaten food and feces,were discharged in the coastal waters of the shrimp farming area;about 84.84 kg of carbon,23.98 kg of nitrogen and 2.34 kg of phosphorus in the form of shrimp products stayed in the vicinity of the consumer market;about7.91 kg of carbon,1.94 kg of nitrogen and 0.28 kg of phosphorus in the form of shrimp processing waste were discharged in the vicinity of shrimp processing plant;about 11.08 kg of carbon,3.52 kg of nitrogen and 0.24 kg of phosphorus was sold in the form of shrimp processed products to the domestic market;about 14.49 kg of carbon,4.61 kg of nitrogen and 0.32 kg of phosphorus to shrimp processing products were exported to the United States,Japan,the European Union,and other foreign markets.The gross ecological footprint of the shrimp industry was 11.0983ghm²/ton.The ecological footprint of breeding process,feed production process,shrimp processing,and transportation processwas14.4375×10^-3ghm²/ton,32.667×10^-3ghm²/ton,50.82×10^-3ghm²/ton,and18.51×10^-3ghm²/ton,respectively.The ecological footprint of shrimp culturing was 10.9819ghm²/ton,with 10.3442 ghm²/ton for pond culture and 11.5037 ghm²/ton for high-elevation breeding pond.The protein/ecological footprint ratio of P.vannamei was 0.017 t/ghm²,lower than 0.0338t/ghm² of pork,0.0449 t/ghm² of poultry meat,0.0449 t/ghm² of egg,0.0814 t/ghm² of grass carp,0.233 t/ghm² of wheat,0.165 t/ghm² of corn,and 0.2361 t/ghm² of soybean.Thus,P.vannamei is the protein source with the high ecological cost in several agricultural products studied in this paper.The environmental bottlenecks,prediction of geographical distribution,and management measurements of P.vannamei farming were discussed.