@ shreyas 
in competetive release what u need to understand is that the concept of mutuialism . in mutualism there will be benifit of both the species who are in mutual relationship with each other . 
and if the concept of competetion will be applicable in these organism , then both of them will accept the competetion in a same rate , that is what we called as competetive release . 
that means we are applying the compatetion to the species which shows mutualism . 
COMING TO THE 2ND QUERY 
GAUSS EXCLUSION PRINCIPLE – two species competing for the same resource cannot coexist at constant population values, if other ecological factors remain constant. 
for example – suppose u are growing two types of plasmodium in a single plate , so, 1 of the plasmodium have mechanism to grow in a faster rate , and multiply the offsprings , so, that type of plasmodium will only survive in that plate , and the other species will be eliminated due to avaliability of less food . its clear now ?? 
Resource partitioning is the process whereby similar species exploit the limited resources in an ecological area without one species driving the others into extinction. Through natural selection, each species adopts a pattern of resource usage that isn't competitive.
in the case of resource partitioning there will be diffrent species , not of same species, if same species will be their then competetive principle will apply , 
and if diffrent species , then none of them will extinct completely , and the resource will be divided within those 2 species , thats is what we known as resource partitioning . 
I THINK THEY ARE CLEAR NOW . 
IF ANY MORE DOUBT LET ME KNOW 
ALL THE BEST ..