Irrigation analysis

Fig. 1 Results from a redundancy analysis of stream nutrient concentrations vs. catchment characteristics in 31 headwater catchments in Catalonia (Spain). Note how phosphorus (SRP) and ammonium (NH4) appear associated with urban point and diffuse sources (Urban percent urban land use, Inhabs number of inhabitants, eq. inhab inhabitant equivalents), whereas nitrate (NO3) concentration is positively associated with irrigated agriculture (IrrAg) and bovine cattle units (ECU), and negatively with mean catchment slope (slope) and percent forest land (Forest). The other variables are Area log area, P precipitation, NonIrrAg non irrigated agriculture. Data are from the Catalan water agency (http //ww.gencat.cat/ac)...

The guiding principles in test plot maintenance are to (1) minimize soil surface disturbance at all times, (2) ensure that control and treated plots are similarly maintained, (3) avoid applying other agrochemicals that may interfere with sample analysis or that are otherwise contrary to the purpose of the study, (4) follow the prescribed irrigation policy determined for the study site, and (5) keep bare-soil test plots free of vegetation, as follows. 

Mandal, U.K., Warrington, D.N., Bhardwaj, A.K., Bar-Tal, A., Kautsky, L. Minz, D., Levy, G.J. 2008. Evaluating impact of irrigation water quality on a calcareous clay soil using principal component analysis. Geoderma, 144, 189-197. 

Traditional agriculture views soil as a relatively inert holder of moisture and nutrients. Effort is made to conserve the soil, maintain its structure and resupply nutrients and water as they are removed. The easiest and cheapest way to supply water is through irrigation. The easiest way to supply nutrients is in the most concentrated form, high-analysis chenucal fertilizers. 

Wynen, E. 2002. Bio-dynamic and Conventional Irrigated Dairy Farming in Australia An Economic Analysis. Australasian Agribusiness Perspectives, Paper 50. University of Melbourne, Carlton. 

Field Locations. For each field test location a variety of information is collected and recorded in addition to the samples which are collected. Seven general categories of information can be defined. Three simple ones are 1) test design or plot plan, 2) location and 3) field use history for several years. Field soil characterization 4) includes screen analysis (soil type), pH measurement, and organic matter content. Weather information 5) includes daily temperatures and rainfall and/or irrigations during the test. Application related data 6) consists of dates, application modes, weather conditions at application, calculations and calibrations. Harvest information 7) includes crop name, part, amount, date, and collector. 

Researchers have also used immunoassay techniques for analysis of triazines in soil leachate. Tasli et al. (1996), for example, analyzed soil water from an irrigated com plot by immunoassay and GC/NPD. Amistadi et al. (1997) analyzed leachate collected from different tillage systems for atrazine by EIA and GC/NPD. Guillard et al. (1999) used an EIA to compare the concentration of atrazine in leachate from plots receiving band or broadcast applications. 

Bresler, E. (1978). Analysis of trickle irrigation with application to design problems. Irrig. Sd. 1, 3—17. Brewer, R. (1964). Fabric and Mineral Analysis of Soil. John Wiley, New York. 

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