Due to a recent drought, a farmer has lost quite a bit of soil on his fields because

Rapid evaporation and absence of precipitation

Explanation:

Drought is considered to be one of the natural disaster as every year farmers had to face this problem. It occurs in a particular area due to the lack of precipitation and rapidly increasing temperature condition. It is characterized by a very dry type of climate where the moisture content is very low or absent. Due to drought, the soil becomes dry and there is an absence of organic materials and water content if present gets evaporated. Subsequently, the soil loses its fertility and is rapidly eroded away losing the essential materials by the action of wind.

the food storage products of chrysophytes are oils or the polysaccharide laminarin.   formerly classified as plants, the chrysophytes contain the photosynthetic pigments chlorophyll a and c all but the yellow-green algae also contain the carotenoid pigment fucoxanthin.