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As the public and scientific communities become more aware of the potential for environmental contamination by pesticides, the fate of turf-applied chemicals continues to receive growing attention. In contrast to most agricultural crops, turfgrass is a permanent crop that fully covers the soil surface. As such, pesticide applications are made to turfgrass foliage. Pesticides residing on foliage are subject to the same avenues of dissipation as pesticides in soil. Once on foliage, a pesticide can be absorbed into the leaf, volatilized back into the atmosphere, chemically or microbially degraded, or removed by water. It is well documented that pesticides have been detected in groundwater. However, research on turfgrass seems to indicate that a variety of factors in the turf environment may reduce leaching to levels below those seen in production agriculture. The runoff of pesticides applied to turfgrass has not been studied extensively.

Bereits in der Einleitung wurde die praktische Bedeutung von Drittparteien bei Korruptionsdelikten verdeutlicht. An der uberwiegenden Mehrzahl der AntiKorruptionsverfahren waren Studien zufolge Drittparteien beteiligt. Auch die tagliche Presseberichterstattung ergibt regelmasig Hinweise auf dolose Hand-lungen in Unternehmen, an denen Intermediare beteiligt sind.

Sobald ein Unternehmen den Entschluss getroffen hat seine Intermediare einer Business Partner Compliance Due Diligence zu unterziehen, muss in einem ersten Schritt festgelegt werden, welche Geschaftspartner genau von diesem Prozess erfasst werden sollen. Es bedarf daher einer Inventur der bestehenden Geschaftspartner und der Einteilung in verschiedene Kategorien. Die Herausforderung besteht darin, samtliche Partner zu identifizieren, die fur das eigene Unternehmen ein Korruptionsrisiko darstellen.

Fur Unternehmen und Unternehmensleiter besteht weitestgehend kein Ermessen bei der Frage, ob sie ihre Geschaftspartner einer Integritatsprufung unterziehen oder nicht. Sowohl gemas den deutschen Vorschriften als auch den Vorschriften des FCPA und des UK Bribery Acts kann das Verhalten von Intermediaren zu einer Verantwortlichkeit fuhren und dadurch mindestens ein Busgeld auslosen. Unternehmen konnen damit nicht ohne weiteres mit einem Berater ko-operieren, der in einem korruptionsanfalligen Land den Erfolg eines Projektes verspricht und dafur exzessive Provisionen verlangt.

Im internationalen Wirtschaftsverkehr kann auf Kooperationen mit Intermediaren kaum verzichtet werden. Unter den Begriff sind alle Parteien zu fassen, die zwischen dem eigenen Unternehmen und den Kunden, Lieferanten aber auch offentlichen Institutionen wirken.

Anders als bei direkter Korruption, bei der Mitarbeiter unmittelbar an Bestechungshandlungen teilnehmen, erfolgt bei indirekter Korruption eine Zwischenschaltung von und damit auch die Tathandlung durch unternehmensexterne Dritte. Zu berucksichtigen sind dabei auch Konstellationen, in denen der Intermediar ohne Wissen und Wollen des Unternehmens Schmiergeldzahlungen leistet, etwa um sich eine lukrative Provision zu sichern. Die Geschaftsleitung kann dann zumindest argumentieren, nichts von den Praktiken gewusst zu haben.

Fertilizers and pesticides applied to home lawns can contaminate surface and groundwater making them unfit for aquatic organisms and human consumption. Application of fertilizers and pesticides can...

Phosphorus losses from turfgrass areas are perceived to contribute to water quality prob- lems, yet a comprehensive review of P fate in turfgrass ecosystems is lacking. According to available data in the literature, phosphorus fer- tilizer inputs (2-10 kg ha -1 ) slightly exceed the estimated outputs of phosphorus in clippings (0.4-7.5 kg ha -1 ). Sediment losses from turf areas are negligible, generally limited to estab- lishment, but runoff and leaching losses of P vary from inconsequential to severe depending on rate, source, and timing of fertilizer applica- tion. Soil properties were found to have a larger effect on runoff volume than vegetative prop- erties. Highest runoff and leaching losses of P occurred when rainfall occurred or was simu- lated shortly after P fertilizer application. Leach- ing losses of P have historically been considered relatively minor; however, the limited research results available indicate that annual P leach- ing losses from mineral soils (0.2-0.7 kg ha -1 ) are similar in magnitude to runoff-P losses from turfgrass systems. One major gap in the knowl- edge is how P sources other than fertilizer (i.e., soil and plant tissue) and irrigation affect runoff and leaching losses of P.

Phosphorus (P) loss from urban areas has been identified as a major contributor to declining surface water quality. The objective of this study was to determine the relationship between extractable soil P, depth of soil sampling, and dissolved reactive P (DP) concentration in runoff from turfgrass areas. At each site, runoff was generated on turfgrass and adjoining areas where turfgrass cover was removed. Across all six locations and the wide range of nutrient management schemes, variation of extractable soil P concentration and saturation ratios of 0–2cm samples accounted for 49–59% (r 2 = 0.49–0.59, n = 92) of variation of DP concentration in runoff from bare soil and soil with turfgrass cover. Despite a high degree of soil P stratification, changing sampling depth generally did not improve the relationship between soil test P and runoff DP concentrations. Across the narrower range of soil P levels common to lawns in New York (0–50mg kg−1 Morgan extractable soil P), none of the soil tests or P saturation levels (for 0–2cm depth) could accurately predict runoff P concentrations from soil with turfgrass cover (r 2 = 0.02 to 0.23, n = 72). For bare soil plots, restricting the analysis to the same range (

Little information exists that describes how soil P levels and vertical distribution throughout the soil profile are influenced by fertilization practices and the addition of composted manures. Two field studies were designed to provide more information on how adding P fertilizer or compost influences the concentration and distribution of P in turfgrass soils. Application of P fertilizer at rates of 19, 38, or 72 kg P 2 O 5 per ha/year over a period of 4 or 5 years increased soil P in the upper 0 to 5 cm of soil by a factor of 2.7 to 3.3. Applying P at a rate of 10 kg P 2 O 5 per ha did not increase soil P in the upper 0 to 5 cm of soil. With one exception, soil P levels at depths of 5 to 10 or 10 to 15 cm were not increased by fertilizer applications over a period of 4 or 5 years. In contrast, adding composted poultry or dairy manures to plots at rates of 12 to 24 mm/year resulted in 8 to 333-fold increases in soil P in the upper 5 cm of soil. Soil P levels also increased substantially in deeper layers as a result of poultry compost application, but not for dairy. These findings indicate that common fertilization practices have a much smaller influence on soil P levels compared to composted manures. The benefits of using composted manures must be weighed against the potentially negative environmental impacts that could result from a large increase in soil P layer where runoff occurs.

Turfgrass managers regularly apply K to creeping bentgrass [Agrostis stolonifera var. palustris (Huds.) Farw.] putting greens on the basis of soil test results or in some relation to annual N fertilizer rates. In the many putting greens that have sand rootzones, K is susceptible to leaching, and in calcareous sands, K availability is further limited by high Ca levels. The K requirements for calcareous sand putting greens are not clear. A 2-yr field study was conducted on an L-93 creeping bentgrass putting green grown on a calcareous sand rootzone at Ithaca, NY. Potassium fertilizer was applied with N in 167 mL H2O m 22 at 0, 1, 2, 3, 5, and 6 g K m 22 14 d 21 during the 2002 and 2003 growing seasons. Leaf tissue samples were collected monthly, and soil samples were collected every 56 d. Turfgrass performance characteristics such as color, quality, and ball roll were evaluated visually and quantitatively. Without K addition, soil test K indicators decreased over time, and low levels of soil K (,1.25 mmol 1 M NH4OAc-K kg 21 ) were prevalent in all plots receiving the lowest (, 2gKm 22 14 d 21 )K rates. Potassium application had no beneficial effects on turfgrass performance. We conclude that acceptable creeping bentgrass performance can be achieved across a wide gradient of soil K levels and tissue K contents (255–639 mmol kg 21 dry weight) in calcareous sand rootzones. Recommended levels of soil and tissue K should be reevaluated to avoid gratuitous use of K fertilizers.

Metalaxyl is a fungicide used for control of Pythium spp. diseases in turfgrass. The downward migration of metalaxyl was studied in irrigated lysimeters containing a fine sandy loam soil alone or sand amended with composted brewery waste, composted sewage sludge, peat or zeolite by analysis of the fungicide in leachates collected up to 65 days post application. The Arkport sandy loam soil and sand containing peat, brewery waste or sewage sludge amendments showed somewhat similar patterns of metalaxyl in collected leachates increasing from not detectable initially to peak concentrations between 14 and 21 days after first irrigation and decreasing thereafter. The peak concentrations were in the order: brewery waste > peat > sludge > Arkport sandy loam. In the lysimeter treatments containing sand amended with zeolite, the downward migration of the fungicide with time after application generally increased with the highest attained concentration in the leachate inversely proportional to the total amount of zeolite in the respective lysimeter sand profile. Only small percentages (ranging from 0.21 to 1.22) of the total applied fungicide were accounted for in the leachates. The literature is reviewed and the possible mechanisms of fungicide losses are discussed.

Downward migration of the fungicide, metalaxyl (N-(2,6-dimethylphenyl)-N-(methoxyacetyl)-alanine methyl ester) in irrigated creeping bentgrass (Agrostic palustris Huds) sand lysimeters was studied as a function of two factors: (1) amending sand with peat and (2) density of the bentgrass turf. Based on the determination of metalaxyl in leachates collected at specific intervals following fungicide application, the presence of peat in the sand delayed the downward migration of the fungicide. The percentages of total applied metalaxyl found in the collected leachates generally decreased as turf density and surface organic matter increased. Literature on the subject of the downward migration of metalaxyl in soils is reviewed.

Leaching of the herbicide mecoprop, [2-(4-chloro-2-methyl-phenoxy)propionic acid] (MCPP), was studied on three types of turfgrass soils; silt loam, fine sandy loam and acid sand, to assess the potential for ground water contamination. Each soil was prepared in plots as free draining lysimeters and seeded with Penncross creeping grass to simulate golf course fairways. The downward migration of MCPP was determined from collected leachate water and residue analysis were done by high performance liquid chromatography. The extent of pesticide leaching was determined to be a function of interval after herbicide application, amount of irrigation water and maturity of the turfgrass stand. The irrigation and water collection patterns do not explain most of the differences in the leaching profiles, in particular of the sand plots. The concentration of mecoprop in the sand leachates was high compared to the finer textured soils but decreased substantially with increasing time after herbicide application in all three soils as well as with maturity of the grass and with more biomass from first to third year application. Where groundwater monitoring is being done, MCPP is a likely candidate for residue analysis if the site has very sandy soils.

An earlier study showed that fall application of the fungicide, triadimefon to sandy turfgrass lysimeter plots resulted in rapid appearance of the metabolite, triadimenol in collected leachates but only occasional presence of the parent fungicide. In the present study, it was shown that, if after such fall applications, leachates are collected and analyzed through the following winter and spring, residues of the metabolite, triadimenol, are detectable as late as early June. Factors influencing these results are discussed.

The magnitude of migration of the nematocide, isazofos (O-[5-chloro-1-(1-methyl-ethyl)-1H-1,2,4-triazol-3-yl]-O,O-diethyl phosphorothioate) was investigated in a silt loam and a fine sandy loam soil and an acid sand, each prepared in plots as lysimeters and seeded with creeping bentgrass. The amount of pesticide leaching was determined as a function of time after isazofos application. The magnitude of downward migration of isazofos was sand > silt loam > fine sandy loam.

The downward migration of the insecticide, trichlorfon (o,o-dimethyl-2,2,2-trichloro-l-hydroxyethylphosphonate) was studied in a fine sandy loam, a silt loam and a sand each prepared in lysimeter plots and seeded with creeping bentgrass. The extent of insecticide leaching was determined as a function of interval after trichlorfon application under two irrigation regimes simulating above or below average precipitation. Trichlorfon moved downward quite rapidly with traces still detectable in leachates 23 days following application. The percentages of total applied insecticide recovered in the leachates were in the range of 1 and 4 percent at the lower and higher rates of irrigation, respectively. Factors affecting the various modes of dissipation of trichlorfon are discussed.

The downward movement of the herbicide, mecoprop [2-(4-chloro-2-methyl-phenoxy) propanoic acid], was studied in a silt loam and a fine sandy loam soil and an acid sand, each prepared in plots as lysimeters and seeded with Penncross creeping bentgrass. The extent of pesticide leaching was determined as a function of interval after last herbicide application and volume of irrigation water. Mecoprop moved downward in small but detectable concentrations in both soils but its rate of leaching was high in the sand. The concentration of mecoprop in the leachates decreased progressively with increasing time after herbicide application in both soils and the sand. A method of analysis was developed based on electron capture gas chromatographic determination of a ring nitrated and methylated mecoprop derivative. Factors affecting the downward movement of herbicides of similar structure are discussed.

The leaching characteristics of the fungicide, triadimefon were studied in a silt loam and a fine sandy loam soil and an acid sand each prepared in plots as lysimeters and seeded with Penncross creeping bentgrass. The effect of sampling interval after last fungicide application and volume of irrigation water on pesticide leaching were studied. In both soils and sand, triadimefon was converted to triadimenol, the latter metabolite being present in the leachate of each growth medium. The concentration of triadimenol in the leachates greatly exceeded that of triadimefon and triadimenol and was much higher in the leachates of the sand than in those of the soils. Factors affecting the movement of pesticides in soils are discussed.

The contribution of runoff from various land uses to stream channels in a watershed is often speculated and used to underpin many model predictions. However, these contributions, often based on little or no measurements in the watershed, fail to appropriately consider the influence of the hydrologic location of a particular landscape unit in relation to the stream network. A simple model was developed to predict storm runoff and the phosphorus (P) status of a perennial stream in an urban watershed in New York State using the covariance structure of runoff from different landscape units in the watershed to predict runoff in time. One hundred and twenty-seven storm events were divided into parameterization (n = 85) and forecasting (n = 42) data sets. Runoff, dissolved P (DP), and total P (TP) were measured at nine sites distributed among three land uses (high maintenance, unmaintained, wooded), three positions in the watershed (near the outlet, midwatershed, upper watershed), and in the stream at the watershed outlet. The autocorrelation among runoff and P concentrations from the watershed landscape units (n = 9) and the covariance between measurements from the landscape units and measurements from the stream were calculated and used to predict the stream response. Models, validated using leave-one-out cross-validation and a forecasting method, were able to correctly capture temporal trends in streamflow and stream P chemistry (Nash-Sutcliffe efficiencies, 0.49-0.88). The analysis suggests that the covariance structure was consistent for all models, indicating that the physical processes governing runoff and P loss from these landscape units were stationary in time and that landscapes located in hydraulically active areas have a direct hydraulic link to the stream. This methodology provides insight into the impact of various urban landscape units on stream water quantity and quality.

[1] A reduction in surface water quality in urban watersheds due to nonpoint source phosphorus (P) loading has prompted municipalities to consider management practices to reduce P loss from landscapes. However, locating P source areas can be time consuming and expensive. Use of distributed models allows delineation of P source areas and focused management strategies. Using the spatially distributed soil moisture distribution and routing model, we adapt and validate a dissolved P (DP) loading model for application to an urban watershed, in Ithaca, New York, to identify P source areas. The model calculates DP loss separately for base flow, impervious surfaces, plant-soil complex, and fertilized areas. The load at the outlet is the sum of P loss from the four components distributed throughout the watershed. Both stream and distributed DP loss were well predicted as indicated by comparison with measured data. The model predicted the largest contribution from plant-soil complexes (36%). Impervious surfaces contributed 10% of the total load but as much as 17% in the winter. More important, the impervious surfaces increased DP losses from the adjacent areas due to runoff from the impervious surfaces saturating the soil, thus increasing runoff losses. Fertilizer contributed substantially following application but decreased rapidly thereafter, a result of conversion from soluble to insoluble P. However, fertilization increased soil P levels, and thus DP losses were higher as a whole (19%). Results demonstrate that correctly predicting the coincidence of P and runoff source areas can be a powerful tool to identify and mitigate contamination of surface waters.

Received 30 March 2006; revised 15 September 2006; accepted 10 October 2006; published 10 March 2007. [1] Effective control of nonpoint source contaminants in runoff from urbanized watersheds requires knowledge about the locations of runoff source areas under a variety of conditions. Physical monitoring of spatially variant processes, such as runoff production form variable source areas, is time-consuming and expensive. Thus modeling the processes may provide a valuable cost-effective alternative. In this paper we adapt and validate a variable source model for an urban watershed to predict areas of the landscape prone to elevated soil moisture levels and saturation excess runoff. We modified the soil moisture distribution and routing (SMDR) model to simulate hydrologic processes in an urban upstate New York watershed by considering the impact of impervious surfaces, hydraulic control structures (detention basins), and land use on the water balance. In our model, infiltration excess runoff from impervious surfaces infiltrates in the surrounding soils. Simulated and observed streamflow agreed well, and more importantly, the distribution of soil moisture levels and overland flow throughout the watershed were well predicted. Removing urban features from the model resulted in substantially lower peak stormflows than observed, and the base and interflows increased accordingly. Both modeled and measured distributed results indicated that the more urbanized areas of the study site had both higher soil moistures and runoff losses due to shallower soils, greater upslope contributing areas, and a larger area of impervious surfaces generating runoff. The model results helped identify processes that describe how urbanization impacts integrated and distributed hydrology, which provides useful information for targeted water quality management.

Nutrients in surface and ground water can affect human and aquatic organisms that rely on water for consumption and habitat. A mass-balance field study was conducted over two years (July 2000-May 2001) to determine the effect of nutrient source on turfgrass runoff and leachate. Treatments were arranged in an incomplete randomized block design on a slope of 7 to 9% of Arkport sandy loam (coarseloamy, mixed, active, mesic Lamellic Hapludalf) and seeded with Kentucky bluegrass (Poa pratensis L.) and perennial ryegrass (Lolium perenne L.). Three natural organic (dairy and swine compost and a biosolid) and two synthetic organic nutrient sources (readily available urea and controlled-release N source sulfur-coated urea) were applied at rates of 50 and 100 kg N ha(-1) per application (200 kg ha(-1) yr(-1)). Runoff water collected from 33 storms and composite monthly leachate samples collected with ion exchange resins were analyzed for nitrate (NO3- -N), phosphate (PO4(3-) -P), and ammonium (NH4+ -N). Nutrient concentrations and losses in both runoff and leachate were highest for the 20-wk period following turfgrass seeding. The NO3- -N and NH4+ -N losses declined significantly once turfgrass cover was established, but PO4(3-) -P levels increased in Year 2. Turf's ability to reduce nutrient runoff and leachate was related to overall plant growth and shoot density. The use of natural organics resulted in greater P loss on a percent applied P basis, while the more soluble synthetic organics resulted in greater N loss.

Nitrogen (96 and 192 kg·ha-1·year-1) and K (0, 48, 96, and 192 kg·ha-1·year-1) were applied in factorial combination over 4 years to two creeping bentgrass (Agrostis palustris Huds.) and one Kentucky bluegrass (Poa pratensis L.) field plot locations. Turfgrass wear tolerance and recovery from wear were evaluated in the 3rd and 4th years of N and K application by visually estimating the percentage of unworn turf present at the wheel track of a wear simulator or by determining the fresh weight of turfgrass tissue collected from cores removed within, and outside the simulator wheel track. Increasing the supply of N improved creeping bentgrass wear tolerance in the 4th year, but had no effect on Kentucky bluegrass wear tolerance. Nitrogen did not influence recovery from the wear of either species over 8 to 14 days of evaluation following the imposition of wear. Potassium did not affect the wear tolerance or recovery from wear injury in either species.