your question is not clear for an international forum/ Please - details

thanks

Subject is the topic; research is the hypothesis :)

Subject specific means the department of the particular university from which you have to do PhD dissertation and it can be Forestry, Ecology and Environment department.For instance Central Universities, IITs and State Universities offer degrees according to their area of research interest. Although Research specific means the highlights topic which you are going to Propose your research hypothesis according to the speciality of the guide. Hence, the choices is yours which university you are interested to proposed your research hypothesis.

@Charanakumar. PhD is specialised research dimensions and recruitment process is different. For instance Assistant professor recruitment process in any university is based on the master level with specialised PhD research topic. PhD is specialized topic of the concern subject. Conceptually, you can't do PhD in entire subject. The environment and forestry is combinations of entire ecosphere and one of the broad field itself. In any university or institute department you can't find entire faculty in similar areas of research everyone has their specialties in one topic, like some are ecologist, few

are atmospheric scientist few are taxonomist and few are chemist etc. Hence Don't confused between research topic and entire subject.