The 3 doshas represent different qualities as given here. The increase and decrease of the doshas can be understood by observing these attributes in the body.

VataRuksha, Laghu, Seeta, Khara, Sukshma, Chala
PittaSlightly Snigdha,Tikshna, Ushna, Laghu, Visra, Sara, Drava
KaphaSnigdha, Seeta, Guru, Manda, Slakshana, Pichchila, Sthira

Vata represents Dry (Ruksha), Light (Laghu), Cold (Seeta), Rough (Khara), Subtle (Sukshma), Constant movement (Chala) attributes. 

Pitta represents Slightly Moist (Snigdha) ,Sharp (Tikshna), Hot (Ushna), Light (Laghu), Foul (Visra), Flowing (Sara), Liquid (Drava) attributes.

Kapha represents Moist (Snigdha), Cold (Seeta), Heavy (Guru), Slow (Manda), Subtle (Slakshana), Slimy (Pichchila), Stable (Sthira) attributes

Pancha-Mahabhuta And Tridosha

The 5 Principal elements (Pancha-Mahabhuta) that flow in nature and through every cell in our bodies together in different combinations form the 3 constitutional principles known as Doshas.

Doshas are the functional units of the body. They are 3 in number- Vata, Piitta and Kapha. 

They are responsible for formation, maintenance and protection of the body. 

When in equilibrium they provide health and when out of balance they are responsible for disease, ageing and death. Tridoshas form the fundamental principle for treatment in Ayurveda.

VataEther & Air
KaphaWater & Earth