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Updated: Jun 6, 2026
10:49
Laboratory-determined Phosphorus Flux from Lake Sediments as a Measure of Internal Phosphorus Loading
Published on: March 6, 2014
Nonpoint-source nitrogen and phosphorus behavior and modeling in cold climate: a review
Cheng-Wei Han1, Shi-Guo Xu, Jian-Wei Liu
1School of Civil and Hydraulic Engineering, Dalian University of Technology, Dalian, Liaoning, China. cwhan@mail.dlut.edu.cn
Summary
Nonpoint-source (NPS) nitrogen and phosphorus pollution intensifies in cold climates due to soil frost and snowpack. These factors challenge watershed model simulations, necessitating model improvements for accurate nutrient loss predictions.
Area of Science:
- Environmental Science
- Hydrology
- Ecology
Background:
- Nonpoint-source (NPS) nitrogen (N) and phosphorus (P) pollution are primary drivers of eutrophication in aquatic ecosystems.
- Cold climate conditions significantly impact the environmental behavior and transport of NPS N and P.
Purpose of the Study:
- To investigate the influence of cold climate factors on NPS N and P pollution.
- To identify challenges posed by cold regions to watershed-scale pollution models.
- To highlight the need for improved modeling of nutrient dynamics in cold environments.
Main Methods:
- Analysis of N and P accumulation and transformation processes in cold soils.
- Assessment of pollutant transport mechanisms associated with snowpack and snowmelt.
- Evaluation of the impact of frozen soil and snow on nutrient losses.
Main Results:
- NPS N and P losses are exacerbated in cold climates due to soil freezing, reduced plant uptake, and disturbed nutrient transformation.
- Snowpack accumulation and subsequent snowmelt significantly contribute to increased N and P runoff.
- First flush events of NPS N and P are more severe in cold climate regions.
Conclusions:
- Frozen soil and snowpack present substantial challenges for simulating watershed-scale hydrologic and NPS pollution models in cold regions.
- Ongoing model improvements focusing on snowmelt runoff, nutrient losses in frozen soil, and N and P behavior are crucial.
- Future research should evaluate model performance across various scales and hydrological conditions in cold climates.
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