it depends on how deep is the ground water,,, many other parameters in the soil can not transferred to surface /ground water especially insoluble organic/inorganic constituents.  but I recommend to measure the growth parameters of specific plant to reflect the soil health/quality with respect to this specific plant....

Yes, especially needed where irrigation water is polluted with heavy metals/metal kids like arsenic, fluorine, and other pollutants as nitrate, selenium which has adverse effect on soil quality. Besides routine testing of irrigation water is needed where iron toxicity is a problem which develops soil acidity. So also true for saline water also.

I do'nt think so.  I do not have any evidence.   I am also living in a more arid country.  I think that the correlation between soil health/fertility and soils higher up in the landscape would be very poor.  The correlation between the river and the closely associated soils may be better.  Rivers are fed from catchment areas, that my vary in relief and I suppose that the correlation would be better between river content and the catchment area.  Furthermore, soil health should be defined to a specific depth and that depth will determine the correlation. I think the more shallow (less depth), the better the correlation.  But,....it is only my opinion.

I agree that in the broad, salinity would show easier, as well as heavy metal trends.  But the normal NPK, Ca, Mg trends,....no

A good book on P loss to water is "Phosphorus loss from soil to water" edited by Tunney, Carton, Brookes & Johnston, CAB International.

Regards

SAR and RSC of ground water used for irrigation and also of the saturation extract  of soils have direct relevance to the quality of soils. In addition,  concentration of heavy metals  need to be monitored as they cause damage the soils for growing crops.

Obviously, arsenic contamination in ground water correlates well with the harmful levels of soil arsenic and eventually that arsenic is found to be excess level in rice plants and grain, and this is common in many parts of the world. Besides, Excess amount of Fe, Mn, Na have detrimental effects on soil quality. Surface water contaminated by industrial effluent is very common.  Sewage and industrial effluents used to contaminate nearby fields and affect both soil and crops. Many heavy metals like Cd, Ni, Pb and Cr are common in untreated sewage and industrial effluents that also adversity affect soil health. So analysis both ground and surface water would be a good indicator of soil health for ensuring agricultural productivity.

Dear colleagues and friends,yesterday I had the opportunity to look into one historical,probably the first ever article on soil health.Soils and health  by Raphael Pumpelly published in Science volume 6,no.127 pages 30-31.Dr Susanta provided this article as reference in one the researchgate questions on history of soil health card.Though the article was published in 1885,130 has years back,  a lot  of good thoughts were presented in that article.Soil ,water and air are linked in health,especially in the movement of pollutants and pathogens.He linked river water contamination with urban house  contamination and farm wells to on farm activities and farmhouse-hold activities.He highlighted the importance organic matter and microbes in soil health .Hygiene and heath of farm soils,farmhouse and farm wells  are interconnected and important in human health.This is what I could get from the article.You may get much more and  like to read it.The question I put up is inspiration from the article.

The question is a bit intricate. State away, we can predict the soil quality (at equilibrium) with respect to EC, SAR and even metals in the surface irrigation water with reasonable precision. 

The other part of question is soil quality on the basis of ground water quality which will very strongly depend on the depth of ground water. As we all know that the geological water aquifer in the Indian subcontinent as well as many other arid regions is saline and sodic and  at places might contain toxic  contaminants as well. But the shallow ground water might have such problems due to anthropogenic activities that may differ from place to place. Under such situations estimation / prediction becomes more and more difficult.

The plants health as indicator is possible but only from the natural habitats, i.e. halophytes directly reflect saline-sodic nature of soil while glycophytes indicate good soil. I know there was a farmer in our district. His farm land was very highly saline-sodic up to a depth of 120 cm. He used to apply 10 bags of gypsum each year along with 6-8 bags of SSP or 5-6 bags of TSP and 3-4 bags of urea. He was getting > 1400 kg grain per acre. This just appeared to me that all the nutrients were made available within few cm of surface and salt prom below was not affecting the crops.

Dear colleagues,so far we viewed soil health with a perspective of sustaining the plant productivity,and due attention was not paid to air and water quality in that particular agricultural area .Also we have not seen whether the soil health supports the human heath and habitation in that area.If we try to link the soil health with water quality in the area (both in wells and ponds) and health of people in the area ,we have to give due weight age to all agricultural practices being carried out on agricultural lands.Also if the water is geologically  affected with the problem of toxic elements like arsenic or selenium or contaminated with municipal solid or liquid wastes resulting in contamination of water with heavy metals.Irrigation with such waters affects the soil health.As pointed out by colleagues, the shallow waters will be much affected.Also  industrial and urban activity near river also affects the river water quality and in turn soil health.From  accumulation of nitrates in soil, the ground water will be affected. If soil has accumulation of phosphate ,through erosion it will reach nearby water bodies.So the geologic or anthropological contaminants can flow from soil to water or from water to soil and ultimately affect human and animal health.

Dr. You have very correctly synthesized the whole scenario. I recall while one of my Ph.D. student was working in raw sewage irrigated vegetable field around Faisalabad, I happen visit this area frequently particularly conducting farmer interviews. there was a reasonably high concern and human as well as animals ailments among farmers. Of course farmers were getting very high yields with out the application of synthetic fertilizers. This situation seemed me very similar to the case Selenium accumulation in one lake water and subsequent birds bone problems and later Dr. Frenkinberger proposed a solution of Se contamination through its conversion into Se-gas with the inoculation of area with some fungi. Hence you are very correct in saying the water and soil heath effects plants from where these toxines get their entry int food chain of animals and human being. And I am sure all these toxic contaminants originate from geological and anthropogenic sources.

Dr.The examples given by you are  relevant and can form useful case studies.Our research should be oriented to such studies linking land management/urban activity to water quality to human/animal heath in the area.In India also we have similar examples of growing vegetables with sewage water in peri-urban areas and possible excess accumulation of some pollutant elements and pathogens especially in leafy vegetables.