Manures may be of two broad groups, 1. Bulky organic manures such as FYM, Compost, Green manure, Crop residues etc 2. Concentrated organic manures such as Oil cakes, Blood meal, Fish meal, Meat meal, Hoof meal etc.

FYM is the decomposed products of dung, urine, litter and left over fodder fed to the cow or bullock or horse having on an average 0.5% N, 0.2% P2O5 and 0.5% K2O and can be used in any type of soil. Compost is another product of organic residues of plant and animal origin, which you may use in all types of soil having in general 16% C, 0.5% N, 0.5% P2O5, 1% K2O. Green manure crops supplies organic matter as well as nutrients particularly N, if it is a legume crop, which also can be used in all types of soils.

 But you have to be careful to choose concentrated organic manures. For example, bones or bone meal consist of calcium phosphate together with fats and proteins, these are good sources of lime, phosphate and N. So it is best suitable for acid soils. Fish manure are quick acting manure and suitable for all soil types. Guano, the dried excreta of sea birds is contains only N and P2O5, so it is not suitable for K deficient soil and so on..... Therefore, accordingly you have to choose your required manures most suitable for your soil.

When you talk of manures vis-a-vis soil health, we should most importantly consider them as complete plant food with with good carriers of microbes   . Soil quality was fi rst defined by the Soil Science Society of America in 1997 as “the capacity of a specifi c kind of soil to function, within natural or managed ecosystem boundaries, to sustain plant and animal productivity, maintain or enhance water and air quality, and

support human health and habitation” . The Natural Resources Conservation Service of the United States Department of Agriculture (USDA) explained the concept in much simpler terms: “soil quality is how well soil does what we want it to do”

Its like opening the pandora box of issues over issues while debating this issue...

When talking about manure which can have quite a few issues from weed seed, to smell, pathogens, bulkiness, salts and little long term soil benefit I would suggest compost is the better choice. More benefit to the soil and environment can incur when crop residues and animal manures are properly composted rather than applied raw. It improves sanitation and give more benefits for the environment. When compost can done under a open roof the addition of water can create the optimized environment that does not support excess losses by precipitation. The use of temperature monitoring can be used to not overturn to eliminate dangers of excessive volatilization and the materials can be turned gently. Compost and manure both can lead to optimized crop production but the use of compost give better long term soil dynamics based on it greater longevity. A strong point of raw manure is its quick reactiion time providing more early nutrients in soluble forms. Manure teas and compost teas can give quick responses while compost give more season long response. 

Do we really have choice of manure at our disposal to use as per nature and properties of soil , considering manures as complete nutrient source, however, there is a great variability with regard to quantum of bio-available nutrients.  

Dr. Srivastava, your statement is partially true, we have little choice of manures but if we prepare the compost we can fairly control the nutrient source as per our desire. However, we have to be very accurate in selection of organisms, size of pit, inoculum addition, organic layering, harvesting time, C:N ratio, watering, and methods and time of inoculum addition. Probably then we may fairly control the bio-available nutrients to the desired level.

Dr Tarafdar ,   let's accept the reality of the issue. We never adopt this practice and neither, it is possible to regulate the nutrient concentration of any manure or compost. We hardly have any idea about the possible extent of bio-available nutrients released through such organic sources. And, therefore, the magnitude of response of any manure will vary on different soil types and crops  ( Annual versus perennial crops) as well.

Dr. Srivastava, I fully agree your views that the magnitude of response of any manure depends mainly on the soil types and on crops we are applying. But I still believe that regulation  of nutrient concentration in the compost can be managed after using scientific way of preparation.

 Thanks a lots  to professor Tarafdar ,Srivastava and Hepperly for your  contribution in these discussion,  (( Do we really have choice of manure at our disposal to use as per nature and properties of soil , considering manures as complete nutrient source, however, there is a great variability with regard to quantum of bio-available nutrients)) this saying  by Professor Srivastava exactly what I mean.

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Dr. Elsheikh, there is no doubt that the manures have the potential as it was the only source of replenishing soil fertility until the manufactures of fertilizers. We have now the choice of manures like, FYM, compost, vermicompost, green manuring, concentrated organic manure, enriched organic manure with suitable microbial inoculates, sewage and sludge, distillery effluents (spent wash), as well as different bio-fertilizers to use under different crops and soil conditions. We have also Arbuscular mycorrhizae, organic matter decomposers as well as plant growth promoting rhizobacteria ( PGPRs). Moreover, we have now fairly standardized the use of all the techniques. Only problem is dissemination of knowledge to the farmers when it needed most.

I agree with the ideas of Drs. J. C. Tarafdar, Paul Reed Hepperly and  Anoop Kumar Srivastava.

Dr Ghafoor , you have to throw out your response. To what an extent , you can adjust the crop nutrient requirement using these variety of so called manures, since  the quantum of bioavailability of different nutrients is so variable and conditional to  prevailing soil conditions, in addition of crops differential nutrient requirement ..??

Dear Dr. Srivastava

I do not think any thing so wrong in my response rendering it to "thorough out". However, it might be your feeling which might not be correct all the times. Better way is simply you may ignore the response of any person.

Dr Ghafoor , i meant , we need your feedback , nothing beyond it . You have misspelled my words, its throw out, NOT THOROUGH OUT..Regards

Dear Sir, You asked for ideas on learning more about organic amendment and its use. For your conditions I would suggest finding the local wastes. Then use these in a pit compost system. Get familiar with compost life by monitoring the changes in temperature in a long stemmed metal thermometer. Get familiar with changes in odor and texture. Learn the stink bag test which is the completely saturate a grap sample with water than seal in a plastic bag if it does not generate stink you have mature compost. Use compost in planting holes and as mulch and note response. Try different levels and positions for your compost use and use on different crops. Keep a journal and this will help you under actions, needs and issues.

PRH