Modeling of non-point source nitrogen pollution from 1979 to 2008 in Jiaodong Peninsula, China

Abstract

Abstract:Efforts to reduce land-based non-point source (NPS) pollutions from watersheds to coastal waters are ongoing all around the world. In this study, annual yield of NPS nitrogen (NPS-N) pollution in Jiaodong Peninsula, China from 1979 to 2008 was estimated. The results showed that: from 1979 to 2008, NPS-N yields exhibited significant inter-annual variations and an increasing trend on decadal scale. High NPS-N yield was mainly found in east and south parts, as well as the urbanized coastal regions in Jiaodong Peninsula. Among the 32 river basins, the three largest basins yielded more than 41.16% of the NPS-N. However, some small coastal watersheds along the South Yellow Sea and Jiaozhou Bay had higher per unit area yield. Most of the small watersheds characterized by seasonal runoff had coastal waters pertain to mild and moderate pollution levels. The ratio of watershed area to shoreline length and the up-stream land use had significant impacts on NPS-N flux through the shoreline. Among the four adjacent coastal areas of Jiaodong Peninsula, Jiaozhou Bay was the most noteworthy one not only because of high levels of land-based NPS-N pollution but also because of its nearly enclosed structure. The combination between integrated coastal zone management and integrated river basin management, land use planning and landscape designing in Jiaodong Peninsula is recommended.

Challenges and opportunities of German-Chinese cooperation in water science and technology

“…Chemical fertilizers, poultry and livestock breeding, aquaculture, and rural living are the major sources of elevated chemical oxygen demand, ammonia-nitrogen, total nitrogen, and total phosphorus loads discharged to receiving watercourses. In China, NPS pollution control will be one of the most important issues in water environmental protection in the next several decades (Hou et al 2014). To control NPS pollution, it is important to increase the knowledge of governing pathways and transformation processes of nutrients from land to water and to improve our opportunities to quantify these processes to further develop abatement strategies.…”

An Overview of China’s Agricultural Non-point Source Issues and the Development of Related Research

“…The Soil Conservation Service (SCS) Curve Number (CN) equation is widely used in NPS studies by Chinese scholars when considering factors that influence the spatial differences of an underlying surface (such as land use, soil permeability, and rainfall) [6,7]. Li and Shen [8] presented storage, saturation excess, and integrated runoff yield theories of regional agricultural NPS runoff yield calculations based on China's actual situation.…”

Coupling ITO3dE model and GIS for spatiotemporal evolution analysis of agricultural non-point source pollution risks in Chongqing in China

“…Currently, the premise of effectively solving the problem of AGNPS lies in the accurate evaluation of the risk state distribution, the risk level, and the risk evolution situation of AGNPS. In particular, the integration of numerous technologies and methods, such as models for the calculation of AGNPS 3 , the universal soil loss equation (USLE) 4 , and GIS technology 5 , has greatly promoted the research on AGNPS in China 6 .…”