What type of soil is formed from weathered parent material and does not exhibit significant horizon development?

The type of soil formed from weathered parent material and characterized by minimal horizon development is known as Entisol. Entisols typically form in environments where the formation process is relatively young or where disturbances such as flooding or erosion limit the accumulation of organic matter and other soil-forming processes. This leads to a soil profile that lacks distinct layers, or horizons, which are more commonly seen in soils that have had more time to develop or are influenced by specific climatic or biological conditions.

In contrast, Gelisols are soils that generally form in very cold environments and exhibit permafrost, which influences their development differently. Histosols are organic soils that develop in wetlands and typically have a significant accumulation of decomposed plant material, leading to a well-defined horizon. Spodosols are characterized by having a subsurface layer enriched with leached materials, particularly iron and aluminum, and exhibit more pronounced horizon development due to specific climatic conditions, primarily in cooler, forested regions.

Thus, Entisols stand out as soils that do not show significant horizon development as a result of their relatively young formation process and the influence of environmental conditions.