We study the infrared ( K _ { s } band ) properties of clusters of galaxies in the Ursa Major supercluster using data from 2MASS ( Two-Micron All-Sky Survey ) and SDSS ( Sloan Digital Sky Survey ) .
We identified three large filaments with mean redshifts of z = 0.051 , 0.060 , and 0.071 .
All clusters of the supercluster are located in these filaments .
We determined the total K _ { s } -band luminosities and masses for 11 clusters of galaxies within comparable physical regions ( within a radius R _ { 200 } close to the virial radius ) using a homogeneous method .
We constructed a combined luminosity function for the supercluster in this region , which can be described by the Schechter function with the following parameters : M ^ { * } _ { K } = -24 ^ { m } .50 and \alpha = -0.98 .
The infrared luminosities of the clusters of galaxies correlate with their masses ; the M / L _ { K } ratios of the systems increase with their masses ( luminosities ) , with most of the Ursa Major clusters of galaxies ( particularly the richer ones ) closely following the relations derived previously for a large sample of clusters and groups of galaxies .
The total mass-to-infrared-luminosity ratio is 52 M _ { \odot } / L _ { \odot } for six Abell clusters and 49 M _ { \odot } / L _ { \odot } for all of the clusters , except Anon2 .

Key words : galaxies , groups and clusters of galaxies .