石澳山仔是岩岸的典型例子，岩石表面受到強烈的海浪沖刷而並無鬆動的石塊。潮間帶的後方會形成一些岩石池，亦有有不同的生態區域。
石澳山仔是香港海藻品種最豐富的地區之一。 在冬季，即海藻季節，整個潮間帶會被具有明顯地帶性的藻類所覆蓋。
較上部分多是綠藻類，如石蒓。在岩池中，亦可找到其他藻類，如珊瑚藻科的藻類。這裡還有季節性的藻類生長的模式。從11月到3月，圓紫菜丶頭髮菜(紅毛菜) 和其他紅藻在會長於較下部分 。從3月到5月，這種優勢被其他紅藻類植物取代，例如具皮多管藻。
由於海藻資源豐富，石澳山仔可用作研究海藻，而這地方亦可成為蒐集海藻作研究之用。該地區還是當地村民收集紫菜， 出售的地點之一，所以石澳山仔也具有其文化價值。

The site represents a typical example of exposed rock shore which is subject to strong wave actions. No loose rock or boulder can be found on the exposed rocky platform. Some rock pools are formed at the back of the intertidal zone. There is a clear zone of rocky shore flora and fauna.
The site is one of the areas with the richest collection of seaweeds in Hong Kong. During winter, the seaweed season, the whole intertidal zone is almost completely covered by marine macro-algae with a distinct zonal pattern. The upper shore is dominated by green algae such as Ulva lactuca (石蒓), In the rock pools, other algae such as the calcareous rhodphyte Corallina (珊瑚藻科) can be found. There is also a seasonal pattern. Porphyra suborbiculata (圓紫菜), Bangia autropurpurea (頭髮菜/紅毛菜) and other red algae dominate the lower shore from November to March. The dominance is replaced by other rhodophytes such as Polysiphonia harlandii (具皮多管藻) from March to May.
Due to its rich collection of seaweeds, the site has been used for research of marine algae. It is a fovourite site for collecting experimental materials for seaweed studies. The area is also one of the few sites in the territory where local villagers tradtionally collect Porphyra (紫菜), Zicai, "purple vegetable") for sale. Hence, the site is also of cultural interest.