for soil erosion will cause agriculture growth loss it has calculated for 1 ha 0.4% loss will be happens/year

A=R*K*L*S*C*P

A- potential long term average annual soil loss in tons per acre per year

R-rainfall and runoff factor

K-soil erodibility factor

LS-slope length gradient factor

I agreed with Nagalakshmi Radhakrishnan and you can use weighted RUSLE which new trend in soil erosion research

Thank you very much for your answers, but RUSLE was used to assess soil loss, but this is about assessing the socio-economic vulnerability of natural disasters (soil erosion and landslides) on the island of Idjwi? I'm looking for surplus indicators.

Patient,

I, for one, am somewhat uncertain about how you are using the term vulnerability.

To me an economic vulnerability to landslides would be, for example, a primary roadway or a port facility that was exposed to the hazard of a landslide. As another example, a social vulnerability to soil erosion might be that a specific indigenous group occupies a hilly area but is being lured into raising a new crop whose cultivation results in unsustainable soil erosion (or lured into using "modern" cultivation methods that increase soil erosion).

Are these the kinds of things you are referring to when you say "socio-economic vulnerabilities?"

Alternatively, are you seeking methods to predict/model the socio-economic impacts of specific natural hazards? Note that a disaster is an overwhelming socio-economic impact of a hazard being realized, for example the occurrence of a landslide. Disaster and hazard are not synonyms. A huge landslide in the middle of nowhere might have no effect on humankind and thus not be a disaster at all. A small landslide in the middle of a densely populated city could be a huge disaster because of the magnitude of the socio-economic impacts it has.

Knowing which of these is your objective (or neither) will help me to know how to respond to your question.

Matthew,

Yes, that's exactly what it is. The impacts of these disasters on infrastructure and agricultural land. Many of the indicators are used (Social Vulnerability Index: SoVI). So I would like to have an idea about suitable indicators in a mountainous area like the island of Idjwi.

The objective is to assess the socio-economic vulnerability of Idjwi populations to the risks of water erosion and landslides. This is where I have to have a vulnerability map drawn up, since the susceptibility map has already been done.