Pietrzak Stefan, Pazikowska-Sapota Grażyna, Dembska Grażyna, Dzierzbicka-Glowacka Lidia Anita, Juszkowska Dominika, Majewska Zuzanna, Urbaniak Marek, Ostrowska Dominika, Cichowska Agnieszka, Galer-Tatarowicz Katarzyna
Department of Water Quality, Institute of Technology and Life Sciences in Falenty, Raszyn, Poland.
Department of Environmental Protection, Maritime Institute, Gdańsk, Poland.
PeerJ. 2020 Jan 7;8:e8396. doi: 10.7717/peerj.8396. eCollection 2020.
In order to counteract the eutrophication of waterways and reservoirs, a basic risk assessment of phosphorus (P) losses in the surface runoff from agricultural land should be included in water management plans. A new method has been developed to assess the risk of P losses by estimating the degree of P saturation (DPS) based on the P concentration of the water extract water-soluble P.
The risk of P losses in surface runoff from agricultural land in the Puck Commune on the Baltic Sea Coast was assessed with the DPS method. The results were compared to an agronomic interpretation of the soil test P concentration (STP). Research was conducted on mineral and organic soils from 50 and 11 separate agricultural plots with a total area of 133.82 and 37.23 ha, respectively. Phosphorus was extracted from the collected samples using distilled water on all soil samples, acid ammonium lactate on mineral soils, and an extract of 0.5 mol HCl·dm on organic soils. The organic matter content and pH values were also determined. The results of the P content in the water extracted from the soils were converted into DPS values, which were then classified by appropriate limit intervals.
There was a high risk of P losses from the soil via surface runoff in 96.7% of the agricultural parcels tested (96% of plots with mineral soils and 100% of plots with organic soils). Simultaneously, a large deficiency of plant-available P was found in soils from 62% of agricultural plots. These data indicate that the assessment of P concentration in soils made on the basis of an environmental soil P test conflicts with the assessment made based on STP and create a cognitive dissonance. The risk level of P losses through surface runoff from the analyzed plots as determined by the DPS indicator is uncertain. This uncertainty is increased as the DPS index is not correlated with other significant factors in P runoff losses, such as the type of crop and area inclination.
为应对水道和水库的富营养化问题，农业用地地表径流中磷（P）流失的基本风险评估应纳入水资源管理计划。已开发出一种新方法，通过基于水提取物水溶性磷的磷浓度估算磷饱和度（DPS）来评估磷流失风险。
采用DPS方法评估波罗的海沿岸普克公社农业用地地表径流中磷流失的风险。将结果与土壤测试磷浓度（STP）的农艺解释进行比较。研究分别在50个和11个单独的农业地块的矿质土和有机土上进行，总面积分别为133.82公顷和37.23公顷。对所有土壤样品均使用蒸馏水提取磷，对矿质土使用乳酸铵，对有机土使用0.5 mol HCl·dm提取物。还测定了有机质含量和pH值。将从土壤中提取的水中磷含量结果转换为DPS值，然后按适当的极限区间进行分类。
在所测试的96.7%的农业地块（96%的矿质土地块和100%的有机土地块）中，土壤通过地表径流流失磷的风险很高。同时，在62%的农业地块土壤中发现植物有效磷严重缺乏。这些数据表明，基于环境土壤磷测试对土壤中磷浓度的评估与基于STP的评估相冲突，并造成认知失调。由DPS指标确定的分析地块通过地表径流流失磷的风险水平不确定。由于DPS指数与磷径流流失中的其他重要因素（如作物类型和面积坡度）不相关，这种不确定性增加了。
