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Proceedings of the International Conference on Land for Waste Management =
1974
Tomlinson, Jocelyn
COMPARING SOLID WASTE MANAGEMENT SYSTEMS FOR SUPERMARKETS
1974
Ricker, Harold S.
BEEF WASTE MANAGEMENT ECONOMICS FOR MINNESOTA FARMER-FEEDERS
1974
Pherson, Carl L.
Planning for the management of solid waste materials in rural areas
1974
Carley, D. H.
Planning for the management of solid waste materials in rural areas
1974
Carley, D. H.
Production theory and community services planning: application to solid waste disposal
1974
Knutson, M. | Boehlje, M. | Schreiner, D.
Extract: A basic management responsibility in community service planning is to evaluate alternative methods of providing various public goods and services such as transportation services, sewage and solid waste disposal, and water for home and industry. these alternative methods frequently involve new or different technologies and various combinations of inputs such as capital and labor. the purpose of this discussion is to develop and relate the concepts of production economics to the provision of community services. the application of these concepts to the allocation of resources in solid waste disposal will provide an empirical example of the type of analysis required. these concepts should be useful to community planners and public works managers in making and justifying resource allocation decisions.
Afficher plus [+] Moins [-]Preliminary investigation into the rheology of dairy shed waste
1974
Dakers, A. J.
With the introduction of stricter control on the final disposal of all forms of farm waste, its transportation is becoming an everyday component of farm management. In the past and at present the design of such transportation systems has been and is being based on criteria for transportation of fresh water with little appreciation of the differences that may or may not exist. Certain research workers have found this difference to be quite significant (13, 15, 31). Estep (36) has suggested that manure pump installations should be designed for a friction loss 10% higher than for water. Grimm et ale (12) found that with total solids (T.S) less than 35,000ppm pressure loss was less than for water. Thus it might be concluded that a considerable amount of work is required before accurate flow characteristics of manure slurries can be understood.
Afficher plus [+] Moins [-]Decision-makers guide in solid waste management | Solid waste management | Technical Report Archive & Image Library (TRAIL)
1974
Colonna, Robert A.
Nitrogen Loss from Manure as Influenced by Moisture and Temperature
1974
Adriano, D. C. | Chang, A. C. | Sharpless, R.
Soil temperature and moisture are important in cattle waste management. The effects of these two variables on N losses from different rates of applied manure were studied under greenhouse conditions at two soil moisture (60 and 90% of water saturation percentage, WSP) and two soil temperature (10 and 25C) levels. The manure rate did not have a significant effect on the percentage of loss of applied N. At 10C, the average losses of applied N were 26 and 39%, respectively, for the 60 and 90% moisture levels. Higher losses of 40 and 45% were obtained for the 60 and 90% levels, respectively, at 25C. Results suggest that these losses occurred largely through volatilization of NH₃. Under conditions where significant nitrification occurred, there were greater concentrations of electrolytes associated with reduction in pH indicating that leaching of NO₃⁻ cannot be divorced from soluble salts in manure disposal areas. With N losses approaching 50% of the applied N, large quantities of N are being volatilized to the atmosphere over large and concentrated dairy and feedlot areas.
Afficher plus [+] Moins [-]The relationship between evapotranspiration and moisture content
1974
McLellan, A.
In development of forage and pasture crop management practices it is important to make effective use of the soil moisture in production of vegetative growth. Although irrigation in New Zealand is on the increase, there seems little conclusive evidence on how much water should be applied to obtain optimum levels of production. With the cost of water likely to increase as more use is made of it, these optimum levels of supply become of economic importance. Information must be available regarding how much water can be used productively for a point is reached where the extra water added costs more than is gained by the increase in yield. It is necessary to learn whether plants having unlimited moisture supply tend to "waste" water as compared with plants having less ample supplies of soil moisture. Within the present meaning a "wastage" of water would be indicated by a relatively high amount of water loss through transpiration per unit of dry matter produced by the plants. The quantity of water removed from the soil by plants is variously termed "water requirements" or “water use” in the literature. A study of the effect of soil moisture content on the evapotranspiration rate is important in crop water requirement studies. The results will influence the timing of irrigation. If evapotranspiration does not decrease as moisture content decreases it may be possible to replenish water less often. On the other hand, if evapotranspiration rate does decrease with decreasing moisture content a more precise optimum point could be found from the relationship, for the timing of irrigation.
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