A total of 224 animal manures and feeds, randomly sampled from different sizes of intensive farms in three northeastern provinces, were analyzed to determine Cu concentration. At the same time, the load of animal manure Cu on farmlands and loss to rivers in sewage irrigation areas of Liaoning Province was estimated. The results showed that the mean Cu concentrations in pig, cattle, and chicken feeds were 179.8, 16.6 and 20.8 mg kg-1, respectively. Cu concentrations in manures ranged from 1.5 to 1521.2 mg kg-1. The mean value of 642.1 mg kg-1 in pig manure was higher than the mean values of 65.6 mg kg-1 and 31.1 mg kg-1 in chicken and cattle manures, respectively. The load of animal manure Cu on farmland in the study area ranged from 12.3-35.4 kg km-2 annually. In particular, the Xiaolinghe area received a higher level than the other areas. The possible amount of manure Cu entering river water as a result of soil erosion was lower than 0.76 kg km-2. The highest loss rates were found in the south of Anshan and the west of Jinzhou. It is suggested that animal manures contain a high level of Cu. Long-term agricultural application of animal manure may increase the potential risk of Cu pollution in soil and surface water.
The Yangtze River is the longest river in China, and the river basin spans one fifth of the area of the whole country. Based on statistical data, the excretion of manure-borne steroid hormones, including steroid estrogens(SEs) and steroid androgens(SAs), in 10 provinces of China within the region has been estimated. The potential environmental and ecological risk of manure-borne steroid estrogens to the surface water in this region was also assessed. The manure-borne SE and SA excretions in the 10 provinces and municipalities vary in the order: Sichuan 〉 Hunan 〉 Hubei 〉 Yunnan 〉 Jiangsu 〉 Anhui 〉 Jiangxi 〉Chongqing 〉 Qinghai 〉 Shanghai. The highest increase of manure-borne SEs(1434.3 kg)and SAs(408.5 kg) was found in Hunan and Hubei provinces, respectively, and the total excretion in 2013 was 65% more than 15 years earlier in these two provinces. However, the emissions in Anhui and Shanghai decreased in this 15 year period of time. Swine urine,chicken feces, cattle urine, and laying hen feces were considered the dominant sources of manure-borne E1, βE2, αE2, and SAs, respectively. Although Jiangsu province did not have the largest excretion of manure-borne SEs, it had the highest level of predicted17β-estradiol equivalency(EEQs) value of 16.65 ng/L in surface water because of the limited surface water resources. According to the lowest observable effect level of 10 ng/L for17β-estradiol, the manure-borne SEs in Jiangsu province might potentially pose ecological risk to its wild aquatic organisms.
Yanxia LiShiying GaoShufang LiuBei LiuXuelian ZhangMin GaoLinjie ChengBoyang Hu