Wetlands are valuable ecosystems protected under Section 404 of the Clean Water Act, and accurate delineation of wetlands is thus important for their continued preservation. The standard method for wetland delineation includes identifying hydric soils based on their distinctive hydromorphology, which often includes gley colors. However, in some cases soil colors can be misleading. One example is hydric soils derived from problematic red parent material (PRPM), which fail to exhibit the dominantly gray colors commonly observed in soils formed under hydric conditions. Recently, the widespread distribution of soils derived from PRPM was tied to red‐bed formations of Mesozoic or Paleozoic age, with deep red colors associated with large hematite crystals. The color change propensity index currently used to test (in the laboratory) for PRPM soils takes many hours and requires specialized expensive equipment, which may substantially delay assessment. The objective of this study was to develop a rapid field test that could be used to recognize soils formed from PRPM. The proposed field test and calculated One Hour Color Index can be used to determine if soils are derived from PRPM with 90% accuracy, using easily accessible chemicals and equipment (sodium dithionite, sodium chloride, distilled water, plastic test tubes) and a Munsell color book.

中文翻译：

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现场测试以识别有问题的红色母材

湿地是《清洁水法》第404条所保护的宝贵生态系统，因此，准确划定湿地对于继续保护它们至关重要。划定湿地的标准方法包括根据其独特的水形态识别水土，通常包括hydro色。但是，在某些情况下，土壤颜色可能会产生误导。一个例子是衍生自有问题的红色母体材料（PRPM）的含水土壤，这种土壤不能表现出通常在含水条件下形成的土壤中常见的显性灰色。最近，PRPM衍生的土壤的广泛分布与中生代或古生代的红层形成有关，深红色与大的赤铁矿晶体有关。当前用于（在实验室中）测试PRPM土壤的色变倾向指数需要花费数小时，并且需要专用的昂贵设备，这可能会大大延迟评估。这项研究的目的是开发一种快速的现场测试，可以用来识别PRPM形成的土壤。拟议的现场测试和计算得出的“一小时颜色指数”可用于确定土壤是否源自PRPM，并使用易于获得的化学药品和设备（连二亚硫酸钠，氯化钠，蒸馏水，塑料试管）和孟塞尔颜色进行测定。书。