皖北采煤沉陷区水域周边土壤磷赋存形态分布特征研究

Distribution Characteristics of Phosphorus Speciation in Soils around the Subsidence Waterlogging Area in Coal Mining Area in Northern Anhui Province

摘要: 采煤沉陷区水域属于特殊的水生态系统，其周边土壤与沉陷区水环境质量存在紧密联系。土壤中不同形态的磷通过径流和淋溶等方式进入采煤沉陷区水域，导致水域富营养化。本研究选取皖北矿区9个采煤沉陷区水域周边土壤为研究对象，包括祁南矿(QNK)、卧龙湖矿(WLHK)、桃园矿(TYK)、钱郢孜矿(QYZK)、芦岭矿(LLK)、孟庄矿(MZK)、刘桥二矿(LEQK)、朱仙庄矿(ZXZK)和杨庄矿(YZK)。采用SMT法(Standard Measurements Testing)测定土壤中总磷(TP)、无机磷(IP)、有机磷(OP)、铁铝结合态磷(Fe/Al-P)和钙结合态磷(Ca-P)的含量，旨在评估周边土壤中磷的生态风险。结果表明：土壤中的TP的平均含量为563.33 mg∙kg⁻¹，IP是TP的主要形态(60.80%~86.38%)，Ca-P可能是IP主要形态(54.11%~86.79%)，人为活动可能是驱动磷形态空间分布的主要因素。YZK和QYZ沉陷区周边土壤的磷污染指数均已超过1.2，这些区域磷负荷较高，受人为活动影响较大，高污染的地区易随径流进入水体而造成水域富营养化风险。OP与TP存在正相关(r = 0.67, p < 0.05)，但与其他磷形态的相关性较低，说明OP主可能是外源输入为主。TP与Ca-P存在正相关(r = 0.70, p < 0.05)，Ca-P易随雨水迁移进入水体，形成潜在的释放源，导致水体富营养化的产生。因各采煤沉陷区水域所处地理位置不同，以及农业活动、生活污水和工业废水等人为活动，导致其污染状况呈现出地方性分布差异。本研究成果为采煤沉陷区后续治理及控制采煤沉陷区水域水体富营养化提供了科学依据，并对生态安全维护与风险管理提供理论支撑。

Abstract: The subsidence waterlogging area in coal mining area is a special water aquatic ecosystem, with the surroundings soil forming important sources and sinks. Different forms of phosphrous in the soil enter the subsidence waterlogging area in coal mining area through runoff and leaching, leading to eutrophication of the water. This study focuses on 9 the subsidence waterlogging area in coal mining area in the northern Anhui mining region, including Qinan Mine (QNK), WOlong Lake Mine (WLHK), Taoyuan Mine (TYK), Qian Yingzi Mine (QYZK), Luling Mine (LLK), Meng Zhuang Mine (MZK), Liuqiao No.2 Mine (LEQK), Zhu Xianzhuang Mine (ZXZK), and Yang Zhuang Mine (YZK). Using the Standard Measurements Testing (SMT) method to texting the contents of total phosphorus (TP), inorganic phosphorus (IP), organic phosphorus (OP), iron-aluminum unite phosphorus (Fe/Al-P), and calcium unite phosphorus (Ca-P) in the surrounding soil, aiming to evaluate the ecological risks of phosphorus in the surrounding soil. The results showed that the average content of TP in the soil was 563.33 mg∙kg⁻¹. IP was the main form of TP (60.80% to 86.38%), Ca-P likely was the main form of IP (54.11% to 86.79%), human activities may be the primary factor driving the spatial distribution of phosphorus forms. The pollution index of YZK and QYZ had exceeded 1.2, these areas had a high phosphorus load and were more influenced by human activities, highly polluted areas were prone to enter water bodies through runoff, posing a risk of eutrophication in the water areas. OP had a positive correlation with TP (r = 0.67, p < 0.05), but had a lower correlation with other forms of phosphorus, further explanation: OP was likely dominated by exogenous inputs. There was a positive correlation between TP and Ca-P (r = 0.70, p < 0.05). Ca-P was prone to move into water with rainwater, forming potential release source and leading to eutrophication of water. Due to the different geographical locations of the subsidence waterlogging area in coal mining area, and human activities such as agricultural activities, domestic sewage and industrial sewage, these results in local differences in pollution conditions. The findings of this study provide a scientific basis for the subsequent management and control of eutrophication in the subsidence waterlogging area in coal mining area, and offer theoretical support for ecological security maintenance and risk management.