@ARTICLE{Krajewski_Adam_Estimating_2026,
 author={Krajewski, Adam and Hejduk, Leszek},
 volume={vol. 52},
 number={No 1},
 pages={110-117},
 journal={Archives of Environmental Protection},
 howpublished={online},
 year={2026},
 publisher={Polish Academy of Sciences},
 abstract={The Curve Number method, developed in the 1950s in the United States, is commonly used to estimate runoff depth resulting from heavy rainfall. Over many years, it has been tested in various regions and for purposes beyond its original use. Despite numerous studies on this method, some issues still require consideration, i.e., a universally accepted procedure for CN determination from rainfall-runoff data. In this work, the authors attempt to estimate the CN parameter for a small, lowland catchment in central Poland. Historical data on catchment land cover and original rainfall-runoff measurements are used to determine the CN values for three periods characterized by different catchment land-cover structures. The applied approaches for CN estimation are compared and discussed. The study indicates that: i) over the period 1974-2018, a gradual increase in forested areas was observed, accompanied by a decrease in the average CN value (on average, a 1% increase in forest cover reduces CN by 0.2), ii) among approaches based on rainfall-runoff data, the least-squares calibration appears to be the most straightforward method for CN estimation; while the asymptotic approach may additionally identify a threshold rainfall beyond which the method is applicable; iii) the accepted initial abstraction ratio plays a key role in CN estimation and water-routing modelling, and further research is required to improve runoff prediction.},
 title={Estimating Curve Number under changing catchment’s land cover structure},
 type={Article},
 URL={http://www.journals.pan.pl/Content/138271/PDF/Archives%20vol%2052%20art%209.pdf},
 doi={10.24425/aep.2026.158387},
 keywords={CN method;, rainfall-runoff;, initial abstraction;, afforestation;, rural area;},
}