Mid-field natural ponds promote regional biodiversity, providing alternative habitats for many valuable animal species. The study’s objective was to determine the most important abiotic factors, including hydrochemical and morphometric parameters, affecting fish occurrence in natural, small water bodies on agricultural lands. The studies were conducted in nine randomly selected water bodies located in Poland (the North European Plain). Eleven species of fish were recorded in the waterbodies, with the most abundant being cyprinids (mainly crucian carp). Canonical correspondence analysis (CCA) showed that an increase in oxygenation, temperature, amount of macrophytes, and K concentration and a decrease in the concentration of phosphates, electrical conductivity (EC), Mg, and Cl is associated with the most beneficial living conditions for the most frequently occurring species in the studied water bodies—crucian carp and tench. Aside from the hydrochemical parameters of water in the natural ponds, the number of fish correlates with the basin area and the pond area, maximum depth, area of the buffer zone surrounding the water bodies, and the number of macrophytes. This last factor also has a significant influence on the species’ abundance in the water bodies. Fish occurrences in mid-field ponds and common knowledge on their important role in the environment require taking steps to provide fish protection.

中文翻译：

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不同非生物条件对位于农田的小型天然水体中鱼群结构和生物多样性的影响

中场天然池塘促进区域生物多样性，为许多有价值的动物物种提供替代栖息地。该研究的目的是确定最重要的非生物因素，包括水化学和形态测量参数，这些因素影响农田自然小水体中鱼类的发生。这些研究是在位于波兰（北欧平原）的九个随机选择的水体中进行的。水体中记录了 11 种鱼类，数量最多的是鲤科鱼类（主要是鲫鱼）。典型对应分析 (CCA) 表明，氧合、温度、大型植物数量和 K 浓度增加，磷酸盐、电导率 (EC)、Mg、和 Cl 与所研究水体中最常见的物种——鲫鱼和丁鱼的最有益的生活条件有关。除了天然池塘水的水化学参数外，鱼类的数量还与流域面积和池塘面积、最大深度、水体周围缓冲区的面积以及大型植物的数量有关。最后一个因素也对水体中物种的丰度有重大影响。中场池塘中的鱼类及其在环境中的重要作用的常识需要采取措施提供鱼类保护。鱼的数量与流域面积和池塘面积、最大深度、围绕水体的缓冲区面积以及大型植物的数量有关。最后一个因素也对水体中物种的丰度有重大影响。中场池塘中的鱼类及其在环境中的重要作用的常识需要采取措施提供鱼类保护。鱼的数量与流域面积和池塘面积、最大深度、围绕水体的缓冲区面积以及大型植物的数量有关。最后一个因素也对水体中物种的丰度有重大影响。中场池塘中的鱼类及其在环境中的重要作用的常识需要采取措施提供鱼类保护。