An Economic Analysis of Erosion and Sedimentation in Lavon Reservoir Watershed

Public Law 92-500 - the 1972 Federal Water Pollution Control Act Amendments - mandates the analysis of agricultural non-point source (NPS) pollution controls. This report presents the results of a study of the economic impact of implementing potential agricultural NPS pollution controls in the watershed above Lavon Reservoir. The study focuses on: (a) effects of erosion controls on farm income, (b) off-side sediment damages in the watersheds; (c) costs of administering and enforcing alternative erosion-sedimentation controls, and (d) effects of adopting cotton pest management methods. Erosion controls considered include possible regulatory programs as well as voluntary programs combined with economic incentives. While the stimulus for this study was concern over pollution (an off-site problem) it can not, because of long-run farm income consequences, be separated from conservation problems (an on-farm problem). Thus, the study is as much an analysis of conservation economics as it is an analysis of environmental economics. Accordingly, the report contains substantial information on the short and long-run on-farm benefits and costs of various soil conservation practices for all soil mapping units in Lavon watershed The results are applicable to much of the Blackland Prairies Land Resource area

Barium Concentration in Rock Varnish: Implications for Calibrated Rock Varnish Dating Curves

Cation-ratio dating of rock varnish is a recently developed technique for obtaining surface exposure ages of a wide variety of geomorphic surfaces. As originally proposed, the technique utilizes a ratio among minor cations [(K+Ca)/Ti] in rock varnish. Although this varnish cation ratio is related to the Ti concentration, it can also be affected by the presence of Ba that may be partially included in the analyzed concentration of Ti. Barium is a minor constituent found in virtually all rock varnishes sampled from the Lake Mead area, Las Vegas Valley, and the Crater Flat region of southern Nevada. Barium is heterogeneously distributed in rock varnish, associated predominantly with Mn and secondarily with sulfur (detrital barite). Barium concentrations are apparently greater in varnishes found on young surfaces (\u3c 100 ka) than in varnishes found on older surfaces (\u3e 500 ka), and they are apparently greater in varnishes on low elevation surfaces than in varnishes on hill-slope or ridge deposits. In energy dispersive spectroscopy (EDS), Ba Lα and Lβ peaks overlap with Ti Kα and Kβ peaks. Unless decomposed , the overlapping peaks may yield erroneously large values for Ti. We have compared the effect of Ba concentration on calculated varnish cation ratios using: (I) quantitative EDS with the scanning electron microscope (SEM) that decomposes Ti and Ba peaks; (2) quantitative wavelength-dispersive spectroscopy (WDS) with an electron probe microanalyzer (EPM); (3) semiquantitative EDS with the SEM that decomposes Ti and Ba peaks; and (4) semi-quantitative EDS with the SEM that does not decompose Ti and Ba lines. Results suggest small amounts of Ba relative to Ti will not significantly change the value of the calculated varnish cation ratio with or without decomposition. However, if Ba concentrations are high relative to Ti, the effect on cation ratios is pronounced, resulting in anomalously low cation ratios. As younger varnishes and varnishes on topographically lower surfaces apparently have higher Ba concentrations, the effect of Ba on cation ratios calculated for younger rock varnishes and lower surfaces will be greater

Impact of New Irrigation Technology on the Texas High Plains: 1980-2020

Crop production on the Texas High Plains is constrained by limited and erratic rainfall, hence irrigation is important. Presently, 6 million acres, or 50% of regional cropland, are irrigated annually. Irrigation water is drawn from the Ogallala Aquifer, which has a recharge rate near zero, and is being depleted at the present rate of use. Future crop production is dependent on technology, as well as the resources available. Because water is a major limiting resource, technologies that increase plant available water, such as advanced irrigation distribution systems and soil moisture conserving tillage methods, are of particular interest, and are the focus of this study. Two levels of analysis were included. The first, a farm level analysis based upon representative counties showed the similarities and differences of response given particular resource endowments, technological options and price situations. Part of the analysis considers the impact of annual qroundwater withdrawal constraints on discounted net present value for a forty year planning horizon. The discounted net revenue was higher for lower discount rates, better commodity prices, and more advanced technology. However, alternative discount rates, prices, and technology did not change the optimum annual withdrawal limit. Lower initial groundwater resources reduced the revenue level and the optimal annual groundwater decline limit. The other part of the farm firm analysis covers expected costs, returns and cropping patterns for a single period. Prices have a significant influence on production, but a far greater impact on net returns. The value of production is 64% to 85% higher for normal prices versus low prices, while net returns are from 8 to 30 times higher. The amount of available groundwater was not as important as price in the determination of production levels, but it too had a significant impact on net returns. Comparing across representative counties, with prices, technology and groundwater situations held constant, the value of production varied more than $150 per acre, but net returns changed very little. The value of production increases 17% with advanced technology, but net revenue more than doubles. The second level of analysis, a regional analysis, addressed expected changes in cropland use, groundwater pumpage, production levels, input demand, and farm income over the next forty years, under select technology and price assumptions. Water availability and hence use, drops over time, reducing irrigated cropland, gross returns and net revenue. The demand for other inputs does not decline as quickly as water usage, indicating input substitution. Further, the decline in net revenue is greater than the reduction in gross returns or variable costs of production. The intensity of crop production declines and the mix of crops changes, reducing purchased input demand and lowering regional farm income. Advanced technology enhances the value of the groundwater resource, increasing water use especially in the later periods of the time horizon. Nontheless, over the whole 40 years, technologies which improve dryland, as well as irrigated, crop production, such as limited tillage and crop rotations, have a greater impact than advanced irrigation technology. While advanced technology enhances productivity and increases net returns, technology is not a substitute for irrigation. Nor does technology save groundwater resources in the large, since the increased value of the water, given advanced technology, encourages greater use, overall. Advanced technology, however, is important to the future of crop production in the region, since it increased the level of production, and net revenue. Further, the impact of technology was proportionally greater under the low commodity price scenarios than for average prices

Recursive Programming Model for Crop Production on the Texas High Plains

A flexible, recursive programming model of crop production on the Texas High Plains was developed. Besides the linear programming (LP) Optimization routine and recursive feedback section, the model also includes a matrix generator and report writer to make scenario definition and output analysts faster and easier. The production activities for each run of the model, are defined for one acre of a specific crop or crop rotation, irrigated at particular times, using a chosen irrigation distribution system and tillage method, on a given land class. The irrigation level may be zero (i.e. dryland) and the land class can include terracing when appropriate. The objective function for the LP optimization routine is the maximization of net returns (gross returns minus all variable, or variable and fixed, costs) to land, water and management. For static runs, the maximization includes net returns over variable costs only; for temporal runs, over variable and fixed costs. LP constraints include land by soil class, irrigation water availability for each of 18 irrigation periods and a total annual water use constraint. The model can be run as either a static single period optimization or as a recursive, temporal model When operated in the recursive mode, the model will loop through up to 20 iterations, rebuilding the LP matrix for each iteration and writing a report for each period. The feedback section of the recursive model is used to update the groundwater situation after solution of each iteration. The amount of groundwater used is summed and that usage translated into the reduction in aquifer saturated thickness, increased pump lift and reduced well yield per period. The new groundwater situation plus any inputted changes in prices, technical efficiencies or crop yields form the data, from which the production activities and constraints for the next iteration are built. At the end of the prescribed number of iterations, a summary report covering the whole time horizon is written and the discounted present value of net returns is calculated at three prescribed discount rates

An Economic Analysis of Agricultural Soil Loss in Crosby County, Texas

The Federal Water Pollution Control Act Amendments of 1972, Public Law 92-500, established a national goal of eliminating the discharge of pollutants into the nation's waterways by 1985. As a step toward that goal an interim water quality standard of "fishable, swimmable waters nationwide" by July 1, 1983 was set. Under section 208 of this law, each state was required to establish a "continuing planning process" to define controls for agricultural non-point sources of water pollution. Section 208 calls for the development of state and area-wide water quality management plans. The plans are to include "a process to (i) identify if appropriate, agriculturally and silviculturally related non-point sources of pollution, including runoff from manure disposal areas, and from land used for livestock and crop production, and (ii) set forth procedures and methods (including land use requirements) to control to the extent feasible such sources." In an earlier group of technical reports (TR 87, 88, 90, 93, 94) in this series, a model was developed to measure the net social benefits from controlling agricultural sediment given various policy options. This was done by contrasting benefits to be gained from reducing the sediment load in a watershed against costs involved in achieving that reduction using various voluntary or mandatory policies to accomplish the reduction. It was a major conclusion of these studies that no policy which restricted soil loss to less than that which was economically desirable from the farmers own viewpoint would generate benefits greater than the costs involved. This finding, in the watersheds of major sediment control concern lead to a decision to change the base area for this report to a county instead of a watershed and to only deal with the on-farm consequences of various management practices. These on-farm consequences would include the changes in topsoil loss and the yield losses that result from losing topsoil. Also included are profit levels that could be expected from different management practices and how the present value of a stream of these profits would vary over various planning horizons

Erosion and Sediment Damages and Economic Impacts of Potential 208 Controls: A Summary of Five Watershed Studies in Texas

This report summarizes results of economic analyses of erosion and sedimentation in five agricultural watersheds in Texas (see fig. 1). Economic analyses of the study areas considered both the on-farm economics of soil conservation and the economic consequences of various sedimentation control options. These topics were joined in the studies because they deal with different facets of the same problem. Unlike some potential pollutants, soil particles transported from a farmer's field that may become a problem downstream are a valuable resource, not a waste product. Because soil is valuable in itself, some level of soil conservation is going to be economically desirable even if downstream damages are not present or are not considered by the farmer. Results of the studies show that soil conservation does indeed pay in many situations and that its value is greater the longer the planning horizon of a farmer. This suggests that an educational program in this regard may reduce sediment damage while increasing farm income at the same time . Sediment can cause environmental damage (off-site costs) both directly and indirectly. Directly, the soil particles can cause environmental damage by filling up reservoirs and flood control structures and by deposition in other places. Indirectly, sediment can cause environmental costs by carrying plant nutrients that are potential pollutants. For the study watersheds, no evidence was found that the concentration of plant nutrients in the water posed health hazards to livestock or humans, nor caused undue eutrophication in the watersheds. Consequently, the study focused on off-site sediment damages resulting from shortened economic lives of reservoir and flood control structures and from sediment deposition in the watershed. Annualized off-site sediment damages ranged from a high of 26 cents per ton of gross erosion in Lake Lavon watershed to 14 cents per ton of gross erosion in Duck Creek, to 13.5 cents per ton of gross erosion in Lower Running Water Draw, to a negligible amount in Turkey Creek and Cameron County. These estimates are considerably lower than off-site sediment damages in corn belt watersheds (Lee & Guntermann). Policy Options for Controlling Sediment Public policies that can be implemented to abate off-site sediment damages include direct regulation, provision of economic incentives, education, and public investment. For point sources of pollutants, regulations are typically directed toward the pollutant at or near the point of emission into waterways. However, this is infeasible with non-point sources such as sediment because they enter waterways at an infinite number of points. Hence, regulations must be directed toward the practices that cause erosion and thus sedimentation. The economic incentive option includes alternatives such as Federal or State cost-sharing for adoption of conservation practices, and disincentives such as taxes or penalties on erosion. Education is a viable policy option in situations where producers are not adopting soil conservation practices that would be profitable. In these situations a successful education program would increase producer's income as well as reducing off-site sediment damages. Public investment could be used to pay for dredging sediment from reservoirs and flood control structures to prevent loss of flood control, water supply and recreational benefits. Social benefits and costs of various policy options based on direct regulation, taxation, and provision of economic incentives were estimated for three watersheds: Lake Lavon, Duck Creek, and Lower Running Water Draw. Items considered in the benefit-cost analysis were: (a) farm income consequences; (b) off-site sediment damages abated; (c) governmental cost or revenue; and (d) administration and enforcement costs associated with each policy. The major conclusion of this social benefit and cost analysis is that off-site damages are not large enough to warrant controls on agricultural activities in any of the watersheds; that is, the costs to society of controls exceed the total benefits to society for all of the policy options considered. Another conclusion is that an education program that emphasizes the on-farm profitability of conservation practices may reduce sediment damages while simultaneously increasing farm income

An Economic Analysis of Erosion and Sedimentation in Lavon Reservoir Watershed

Public Law 92-500 - the 1972 Federal Water Pollution Control Act Amendments - mandates the analysis of agricultural non-point source (NPS) pollution controls. This report presents the results of a study of the economic impact of implementing potential agricultural NPS pollution controls in the watershed above Lavon Reservoir. The study focuses on: (a) effects of erosion controls on farm income, (b) off-side sediment damages in the watersheds; (c) costs of administering and enforcing alternative erosion-sedimentation controls, and (d) effects of adopting cotton pest management methods. Erosion controls considered include possible regulatory programs as well as voluntary programs combined with economic incentives. While the stimulus for this study was concern over pollution (an off-site problem) it can not, because of long-run farm income consequences, be separated from conservation problems (an on-farm problem). Thus, the study is as much an analysis of conservation economics as it is an analysis of environmental economics. Accordingly, the report contains substantial information on the short and long-run on-farm benefits and costs of various soil conservation practices for all soil mapping units in Lavon watershed The results are applicable to much of the Blackland Prairies Land Resource area

An Economic Analysis of Agricultural Soil Loss in Mitchell County, Texas

The Federal Water Pollution Control Act Amendments of 1972, Public Law 92-500, established a national goal of eliminating the discharge of pollutants into the nation's waterways by 1985. As a step toward that goal an interim water quality standard of "fishable, swimmable waters nationwide" by July 1, 1983 was set. Under section 208 of this law, each state was required to establish a "continuing planning process" to define controls for agricultural nonpoint sources of water pollution. Section 208 calls for the development of state and area-wide water quality management plans. The plans are to include "a process to (i) identify if appropriate, agriculturally and silviculturally related non-point sources of pollution, including runoff from manure disposal areas, and from land used for livestock and crop production, and (ii) set forth procedures and methods (including land use requirements) to control to the extent feasible such sources." In an earlier group of technical reports (TR 87, 88, 90, 93) in this series a model was developed to measure the net social benefits from controlling agricultural sediment given various policy options. This was done by contrasting benefits to be gained from reducing the sediment load in a watershed against costs involved in achieving that reduction using various voluntary or mandatory policies to accomplish the reduction. It was a major conclusion of these studies that no policy that restricted soil loss to less than that which was economically desirable from the farmers own viewpoint would generate benefits greater than the costs involved. This finding, in the watersheds of major sediment control concern lead to a decision to change the base area for this report to a county instead of a watershed and to only deal with the on-farm consequences of various management practices. These on-farm consequences would include the changes in topsoil loss and the yield losses that result from losing topsoil. Also included are profit levels that could be expected from different management practices and how the present value of a stream of these profits would vary over different planning horizons

Somatic Cell Count

This archival publication may not reflect current scientific knowledge or recommendations. Current information available from the University of Minnesota Extension: https://www.extension.umn.edu