Article

Nutrient farming: The business of environmental management

Authors:
  • Wetlands Research, Inc.
  • The Wetlands Initiative
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Abstract

Restored wetlands could be used successfully to address our recurring problems of excess nutrients (and sediments) and flood damages along U.S. rivers. Credit markets for flood storage, nitrogen, phosphorous, carbon, atrazine, sediment, and many other constituents would economically motivate landowners to restore wetlands. The resulting high-quality open space would provide for recreation, wildlife habitat, and biodiversity. By instigating the market for nitrate-nitrogen, we can jumpstart the entire process of using markets to manage ecosystems. The nitrogen market will create a new land-economics paradigm and new opportunities for landowners, particularly farmers.

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... Many of the depictions of response to the pressures for Iowa agriculture to adapt to increasing concern for water quality have focused on the application of practices by farmers (Dinnes et al. 2002), on new opportunities available through policies or programs (Hey et al. 2005), or on local initiatives, such as the strategies and workings of 11 A study by the Iowa Water Survey in 1999 demonstrated that the majority of flowing streams and rivers in the state did not exist in 1850. Through investigation of tiling networks, they determined that many these formed through water channeled off of Iowa's farmland. ...
... There are increasingly agency-sponsored initiatives to develop nutrient markets that would allow other potential polluters to pay farmers for actions to reduce nitrogen and phosphorus runoff. A growing number of farmers seek to ''farm nitrogen'' (Hey et al. 2005) in lieu of maximizing row-crop production (Hey et al. 2005). Iowa Farm Bureau reports that there is significant interest by farmers in implementing water-quality protection and soil conservation practices, as evidenced by the fact that there are far more farmers wanting to sign up for government conservation and wetland restoration programs than resources available to enroll farmers (Iowa Farm Bureau 2006). ...
... There are increasingly agency-sponsored initiatives to develop nutrient markets that would allow other potential polluters to pay farmers for actions to reduce nitrogen and phosphorus runoff. A growing number of farmers seek to ''farm nitrogen'' (Hey et al. 2005) in lieu of maximizing row-crop production (Hey et al. 2005). Iowa Farm Bureau reports that there is significant interest by farmers in implementing water-quality protection and soil conservation practices, as evidenced by the fact that there are far more farmers wanting to sign up for government conservation and wetland restoration programs than resources available to enroll farmers (Iowa Farm Bureau 2006). ...
Article
Full-text available
Conventional agriculture, while nested in nature, has expanded production at the expense of water in the Midwest and through the diversion of water resources in the western United States. With the growth of population pressure and concern about water quality and quantity, demands are growing to alter the relationship of agriculture to water in both these locations. To illuminate the process of change in this relationship, the author builds on Buttel’s (Research in Rural Sociology and Development 6: 1–21, 1995) assertion that agriculture is transitioning to a post “green revolution” period where farmers are paid for conservation, and employs actor network theory (Latour and Woolgar Laboratory life: The construction of scientific facts. Princeton, NJ: Princeton University Press, 1986) and the advocacy coalition framework (Sabatier and Jenkins-Smith, Policy change and learning: An advocacy coalition approach, 1–56. Boulder, CO: Westview Press, 1993) to frame discussions of water and agriculture in the upper Mississippi River watershed, particularly Iowa. The author concludes that contested views of agriculture and countryside, as well as differing views of how agriculture must change to adapt to growing water concerns, will shape coalitions that will ultimately play a significant role in shaping the future of agriculture.
... Specifically, precision conservation techniques around fields and across water pathways and off-site management practices such as buffers, filter strips, riparian zones, sediment ponds, denitrification traps, irrigation and drainage ditches, and other management of natural areas within a watershed can help reduce reactive N transport across the landscape. For example, some researchers have proposed that we can even harvest N and reduce its transport across water bodies by using information about N dynamics to determine the best strategic placement of wetlands as a practice that can increase denitrification and removal of nitrates (NO 3 -N) from surface waters (Hey, 2002;Hey et al., 2005). We suggest that these nutrient management concepts and principles could potentially be used to reduce N transport in the environment. ...
... This new nutrient trading concept may provide an additional factor for consideration by managers deciding what practices to implement to increase N use efficiencies. Several other researchers have reported on the potential to use environmental quality market credits to account for reductions of agricultural N losses and prevention of their transport into water bodies (Glebe, 2006;Greenhalch and Sauer, 2003;Hey, 2002;Hey et al., 2005;Ribaudo et al., 2005). However, we need to be realistic and consider that the dynamics of the N cycle make the quantification of these reductions in N losses difficult, especially when one considers interactions with the temporally and spatially variable hydrologic cycle, weather, soils, management, crop rotations, and other uncontrollable and isolated factors (such as thunderstorms), which may increase leaching and/or denitrification (Delgado, 2002). ...
... Several scientists have reported that it may be possible to use denitrification as a method to reduce the losses of reactive N to the environment (Hey, 2002;Hey et al., 2005;Hunter, 2001;Mosier et al., 2002). This can be achieved by adding a carbon source to the system (Mosier et al., 2002), strategically placing denitrification traps (Hunter, 2001), strategically managing water levels of drainage systems (Strock et al., 2007), and strategically locating wetlands to increase denitrification and removal of NO 3 -N from surface water (Hey, 2002;Hey et al., 2005). ...
Conference Paper
Farmers are getting financial rewards for implementing conservation measures on their farms. Industrial wastewater treatment plants are buying credits generated from these measures to meet their NPDES permit regulatory requirements. This is referred to as water quality trading. The treatment plants find it less expensive to pay agricultural producers to implement conservation practices than to upgrade or install new technologies at their plants, the producers get rewarded for their efforts, and the environment benefits in multiple ways including water quality, wildlife habitat, and carbon sequestration. This paper reviews the approaches to water quality trading, its current status of implementation around the nation, and different tools, including the Nitrogen Trading Tool (NTT) being developed by the USDA/ NRCS in cooperation with USDA-ARS Soil Plant Nutrient Research Unit to facilitate this process.
... Specifically, precision conservation techniques around fields and across water pathways and off-site management practices such as buffers, filter strips, riparian zones, sediment ponds, denitrification traps, irrigation and drainage ditches, and other management of natural areas within a watershed can help reduce reactive N transport across the landscape. For example, some researchers have proposed that we can even harvest N and reduce its transport across water bodies by using information about N dynamics to determine the best strategic placement of wetlands as a practice that can increase denitrification and removal of nitrates (NO 3 -N) from surface waters (Hey, 2002;Hey et al., 2005). We suggest that these nutrient management concepts and principles could potentially be used to reduce N transport in the environment. ...
... This new nutrient trading concept may provide an additional factor for consideration by managers deciding what practices to implement to increase N use efficiencies. Several other researchers have reported on the potential to use environmental quality market credits to account for reductions of agricultural N losses and prevention of their transport into water bodies (Glebe, 2006;Greenhalch and Sauer, 2003;Hey, 2002;Hey et al., 2005;Ribaudo et al., 2005). However, we need to be realistic and consider that the dynamics of the N cycle make the quantification of these reductions in N losses difficult, especially when one considers interactions with the temporally and spatially variable hydrologic cycle, weather, soils, management, crop rotations, and other uncontrollable and isolated factors (such as thunderstorms), which may increase leaching and/or denitrification (Delgado, 2002). ...
... Several scientists have reported that it may be possible to use denitrification as a method to reduce the losses of reactive N to the environment (Hey, 2002;Hey et al., 2005;Hunter, 2001;Mosier et al., 2002). This can be achieved by adding a carbon source to the system (Mosier et al., 2002), strategically placing denitrification traps (Hunter, 2001), strategically managing water levels of drainage systems (Strock et al., 2007), and strategically locating wetlands to increase denitrification and removal of NO 3 -N from surface water (Hey, 2002;Hey et al., 2005). ...
Article
Nitrogen (N) inputs to agricultural systems are important for their sustainability. However, when N inputs are unnecessarily high, the excess can contribute to greater agricultural N losses that impact air, surface water, and groundwater quality. It is paramount to reduce off-site transport of N by using sound management practices. These practices could potentially be integrated with water and air quality markets, and new tools will be necessary to calculate potential nitrogen savings available for trade. The USDA-NRCS and USDA-ARS Soil Plant Nutrient Research Unit developed a web-based and stand-alone Nitrogen Trading Tool (NTT) prototype. These prototypes have an easy-to-use interface where nitrogen management practices are selected for a given state and the NTT calculates the nitrogen trading potential compared to a given baseline. The stand-alone prototype can also be used to calculate potential savings in direct and indirect carbon sequestration equivalents from practices that reduce N losses. These tools are powerful, versatile, and can run with the USA soil databases from NRCS (SSURGO) and NRCS climate databases. The NTT uses the NLEAP model, which is accurate at the field level and has GIS capabilities. Results indicate that the NTT was able to evaluate management practices for Ohio, Colorado, and Virginia, and that it could be used to quickly conduct assessments of nitrogen savings that can potentially be traded for direct and indirect carbon sequestration equivalents in national and international water and air quality markets. These prototypes could facilitate determining ideal areas to implement management practices that will mitigate N losses in hot spots and provide benefits in trading.
... Independent of the approach used to manage conservation across a region, users should consider subsurface flows (Delgado and Berry, 2008;Vadas et al., 2007;Tomer et al., 2007). Precision Conservation Buffers and Riparian Zones also are important tools that can be used to manage variable and temporal flows across regions (Tomer et al., 2007;Dosskey et al., 2002;Lowrance et al., 2000;Hey et al., 2005). There are even opportunities to establish wetlands as nutrient farms if they are established in site specific zones (Hey et al., 2005) and even nutrient traps that can capture phosphorous (Penn et al. 2007) and nitrogen-denitrification traps (Hunter, 2001). ...
... Precision Conservation Buffers and Riparian Zones also are important tools that can be used to manage variable and temporal flows across regions (Tomer et al., 2007;Dosskey et al., 2002;Lowrance et al., 2000;Hey et al., 2005). There are even opportunities to establish wetlands as nutrient farms if they are established in site specific zones (Hey et al., 2005) and even nutrient traps that can capture phosphorous (Penn et al. 2007) and nitrogen-denitrification traps (Hunter, 2001). ...
... There is potential to use grasses, grass-like plants, and forbs to develop riparian herbaceous cover that accounts for temporal and seasonal site-specific hydrology. There is the potential to try to synchronize the vegetation growth and water and nutrient use with periods of maximum water flows (Tomer et al., 2007;Dosskey et al., 2002Dosskey et al., , 2005Dosskey et al., , 2007Hey et al., 2005). ...
Article
Full-text available
During the next four decades soil and water conservation scientists will encounter some of their greatest challenges to maintain sustainability of agricultural systems stressed by global warming and increasing population growth, with higher food and biofuels demands. It has been reported that intensive agriculture without adequate soil and water conservation practices can potentially reduce soil quality, lowering yields and increasing off-site transport of soil particles, nutrients, and agrochemicals that impact water bodies. Precision Conservation offers an alternative to integrate the use of spatial technologies such as global positioning systems (GPS), remote sensing (RS), and geographic information systems (GIS) and the ability to analyze spatial relationships within and among mapped data to develop management plans that account for the temporal and spatial variability of flows in the environment. This paper presents several advances in Precision Conservation during the last five years, and the potential applications and uses of these developments for new modified practices that can contribute to Precision Conservation across the landscape. These new technologies and new advances can help connect flows across the landscape, and improve the evaluation and understanding of connections between agricultural and non-agricultural areas to implement the best viable management and conservation practices across the landscape for sustainability of intensive agriculture that simultaneously provides for higher yields and environmental conservation. We propose that, to maintain the necessary maximum production, a parallel increase in conservation practices must take place to sustain maximum agricultural production. We also propose that Precision Conservation will be an approach to soil and water conservation that will be necessary to synchronize best management practices that maximize yields while reducing unnecessary inputs and losses of sediment and other chemicals to the environment.
... Buffers used at the edge of the fields are an effective vegetative barrier that can reduce off-site transport of sediments and nutrients (Dosskey et al. 2002;Fares et al. 2010;Hey et al. 2005;Lowrance et al. 2000). The spatial variability in flows from out of the field was observed in studies conducted during the 1980s (Dillaha et al. 1986(Dillaha et al. , 1989. ...
... Wetlands can also be used to clean surface waters and reduce the transport of nutrients. Hey (2002) and Hey et al. (2005) reported that strategically placed wetlands across the landscape can be used as nutrient harvest farms to remove nitrate from waters and as tools to clean water, and that ecological engineering concepts can be used to establish these wetlands. New geotechnological tools can be used to assess the water and nutrient flows in a watershed to make strategic decisions about where to place these precision conservation practices in order to increase conservation effectiveness (Berry et al. 2003;Hey et al. 2005 Tomer et al. (2013) used precision geotechnologies to conduct a watershed analysis of the flows of water, sediment, and nutrients from the contributing field areas of the Lime Creek watershed, Illinois, and to develop precision conservation recommendations to increase conservation effectiveness. ...
... Hey (2002) and Hey et al. (2005) reported that strategically placed wetlands across the landscape can be used as nutrient harvest farms to remove nitrate from waters and as tools to clean water, and that ecological engineering concepts can be used to establish these wetlands. New geotechnological tools can be used to assess the water and nutrient flows in a watershed to make strategic decisions about where to place these precision conservation practices in order to increase conservation effectiveness (Berry et al. 2003;Hey et al. 2005 Tomer et al. (2013) used precision geotechnologies to conduct a watershed analysis of the flows of water, sediment, and nutrients from the contributing field areas of the Lime Creek watershed, Illinois, and to develop precision conservation recommendations to increase conservation effectiveness. In developing a precision conservation plan for the whole watershed, Tomer et al. (2013) made recommendations about where to strategically place riparian buffers and what type of riparian buffer should be used considering spatial and temporal information to improve the management of the flow and the capacity to remove nutrients being transported from the watershed. ...
... Buffers, grass waterways, wetlands, and riparian areas can be good conservation tools with the potential to filter and improve water quality (Dosskey et al., 2002;Hey et al., 2005;Lowrance et al., 2000). These practices can help reduce the transport of chemicals, sediments, and denitrified NOrN. ...
... They concluded that the management of ditches, especially the deeper ditches that are continuously receiving the tile flow, presents a tremendous opportunity to reduce the NOrN leaching losses. Hey et al. (2005) reported that there is potential to strategically locate nutrient management farms where waters with high NOrN concentration will flow. Hey et al. (2005) envisioned that these site-specific nutrient harvesting farms will have wetlands and riparian buffers that will be used to clean the water. ...
... Hey et al. (2005) envisioned that these site-specific nutrient harvesting farms will have wetlands and riparian buffers that will be used to clean the water. There is potential to employ these ecological engineering practices using Precision Conservation to reduce the transport of nutrients into the surrounding environment (Berry et al., 2003(Berry et al., , 2005Hey et al., 2005). Shuster et al. (2007) conducted a model simulation to evaluate the prospect of enhanced groundwater recharge via infiltration of urban storm water runoff They evaluated the spatial distribution of expected recharge depth relative to the distribution of soils. ...
Article
Population growth is expected to increase, and the world population is projected to reach 10 billion by 2050, which decreases the per capita arable land. More intensive agricultural production will have to meet the increasing food demands for this increasing population, especially because of an increasing demand for land area to be used for biofuels. These increases in intensive production agriculture will have to be accomplished amid the expected environmental changes attributed to Global Warming. During the next four decades, soil and water conservation scientists will encounter some of their greatest challenges to maintain sustainability of agricultural systems stressed by increasing food and biofuels demands and Global Warming. We propose that Precision Conservation will be needed to support parallel increases in soil and water conservation practices that will contribute to sustainability of these very intensively-managed systems while contributing to a parallel increase in conservation of natural areas. The original definition of Precision Conservation is technologically based, requiring the integration of a set of spatial technologies such as global positioning systems (GPS), remote sensing (RS), and geographic information systems (GIS) and the ability to analyze spatial relationships within and among mapped data according to three broad categories: surface modeling, spatial data mining, and map analysis. In this paper, we are refining the definition as follows: Precision Conservation is technologically based, requiring the integration of one or more spatial technologies such as GPS, RS, and GIS and the ability to analyze spatial relationships within and among mapped data according to three broad categories: surface modeling, spatial data mining, and map analysis. We propose that Precision Conservation will be a key science that will contribute to the sustainability of intensive agricultural systems by helping us to analyze spatial and temporal relationships for a better understanding of agricultural and natural systems. These technologies will help us to connect the flows across the landscape, better enabling us to evaluate how we can implement the best viable management and conservation practices across intensive agricultural systems and natural areas to improve soil and water conservation.
... They concluded that the management of ditches, especially the deeper ditches that are continuously receiving the tile flow, presents a tremendous opportunity to reduce the NO 3 -N leaching losses. Hey et al. (2005) reported that there is potential to strategically locate nutrient management farms where waters with high NO 3 -N concentration will flow. Hey et al. (2005) envisioned that these site-specific nutrient harvesting farms will have wetlands and riparian buffers that will be used to clean the water. ...
... Hey et al. (2005) reported that there is potential to strategically locate nutrient management farms where waters with high NO 3 -N concentration will flow. Hey et al. (2005) envisioned that these site-specific nutrient harvesting farms will have wetlands and riparian buffers that will be used to clean the water. There is potential to employ these ecological engineering practices using Precision Conservation to reduce the transport of nutrients into the surrounding environment (Berry et al., 2003(Berry et al., , 2005Hey et al., 2005). ...
... Hey et al. (2005) envisioned that these site-specific nutrient harvesting farms will have wetlands and riparian buffers that will be used to clean the water. There is potential to employ these ecological engineering practices using Precision Conservation to reduce the transport of nutrients into the surrounding environment (Berry et al., 2003(Berry et al., , 2005Hey et al., 2005). ...
... Examples of off-site practices include vegetative buffers or fi lters and restored and constructed wetlands (Hefting et al., 2003;Jacobs and Gilliam, 1985;Lowrance et al., 1984). Buffers and wetlands reduce nitrogen loads to water through plant uptake, microbial immobilization and denitrifi cation, soil storage, and groundwater mixing (Pionke and Lowrance, 1991;Lowrance et al., 1997;Hey et al., 2005;Mayer et al., 2005). ...
... Restored wetlands have been shown to be effective at reducing the transfer of nitrogen from agricultural land to water bodies (Jansson et al., 1994) and have been proposed as a technique to remove reactive nitrogen from the environment (Hey et al., 2005;Mitsch and Day, 2006 (USDA, NRCS, 2006). For the purposes of this analysis, these practices are defi ned as follows: ...
Article
Nitrogen is an important agricultural input that is critical for crop production. However, the introduction of large amounts of nitrogen into the environment has a number of undesirable impacts on water, terrestrial, and atmospheric resources. This report explores the use of nitrogen in U.S. agriculture and assesses changes in nutrient management by farmers that may improve nitrogen use effi ciency. It also reviews a number of policy approaches for improving nitrogen management and identifi es issues affecting their potential performance. Findings reveal that about two-thirds of U.S. cropland is not meeting three criteria for good nitrogen management. Several policy approaches, including fi nancial incentives, nitrogen management as a condition of farm program eligibility, and regulation, could induce farmers to improve their nitrogen management and reduce nitrogen losses to the environment.
... A similar approach could also be used to identify the areas of the field that are more susceptible to higher nitrate leaching, and where spatial fertigation applications and management zones can be applied to maximize nitrogen use efficiencies and reduce nitrogen losses Delgado and Berry, 2008;. The use of these precision (target) conservation practices will contribute to increased water quality of aquifers, lakes, rivers, and other water bodies, since they maximize conservation effectiveness and reduce erosion, as well as reduce losses of nitrogen and phosphorous, and 89 Conservation Practices for Climate Change Adaptation improve the application of buffers, riparian buffers, and wetlands (Delgado and Berry, 2008;Hey et al., 2005;Khosla et al., 2002;Knight, 2005;Qiu et al., 2007;Sadler et al., 2005;Tomer et al., 2007). It is clear from recent advances in precision (target) conservation that we can implement precision conservation agriculture in a wide range of agricultural systems: from low-tech approaches to help low-input, sustainable systems in Africa (Jenrich, 2011), to high-tech minimum tillage systems that use precision digital elevation data to apply precisely aligned furrows along the contour to capture runoff and reduce erosion . ...
... There is potential to use buffers, riparian buffers, and wetlands to adapt to climate change by reducing the off-site transportation of soil, soil organic matter, nutrients, and other agrochemicals, and to reduce the potential for hypoxia by harvesting nutrients, including nitrate, via denitrification (Hey, 2002;Hey et al., 2005;Hill, 1996;Mayer et al., 2007). These conservation practices have been reported as areas that have the capacity to serve as sinks for nutrients moving from upland agricultural fields, preventing movement to streams (Hill, 1996;Mayer et al., 2007;Vidon, 2010). ...
Article
Farmer management adaptations and use of conservation practices to adapt to a changing climate (e.g., no-till practices, crop rotations, precision conservation, crop selection and dates of planting, harvest, and tillage) have the potential to greatly reduce soil erosion rates. Conservation practices will be key and must be used as strategies for adaptation to climate change impacts on the soil resource. Examples of key strategies are the use of conservation tillage, management of crop rotations and crop residue (including use of cover crops where viable), management of livestock grazing intensities, improved management of irrigation systems, use of technologies, and precision conservation. Many other conservation practices also have the potential to reduce much or all of the potential acceleration of soil erosion rates that may occur under a change in climate that will bring more total rainfall with higher intensity rainfall events, or a change to a drier climate that will potentially bring higher wind erosion rates. One important adaptation practice will be to consider projected spatial changes in the hydrological cycle, such as wetter and drier regions, and periods of drought. This could help in the development and/or implementation of soil and water conservation policies that consider temporal and spatial effects from climate change at the regional level. These policies should also consider conservation practices that contribute to increased water-holding capacity in the soil profile, improved drainage practices, and the development of new crop varieties and cropping systems that are more resistant to drought.
... Restored and created wetlands hold potential to replace the lost acreage and ameliorate ecosystem problems, including discharge of excess nutrients and solids, hypoxia, flooding, and habitat loss (Hey et al. 2005). For example, in the early 1970s researchers in Wisconsin and Florida began studying the effectiveness of wetlands for reducing nutrients in wastewaters (Steward & Ornes 1975;Spangler, Sloey & Fetter 1976). ...
... Interest in the water quality functions of created wetlands was rekindled in the late 1980s and early 1990s because of their perceived effectiveness for treating nonpoint and point source of pollution (Faulkner & Richardson 1989;Hammer & Bastian 1989;Kadlec 1989;Moshiri 1993;Olson 1993). Hey et al. (2005) proposed restoring 130,000 ha of wetlands in the Upper Mississippi basin as nutrient ''farms'' to remove nitrogen. In northeastern Illinois, restored wetlands are promoted to municipalities as a cost-effective means of improving water quality in streams degraded by agriculture and urban development (Illinois Municipal League 1991;Technical Note #78 1995). ...
Article
In northeastern Illinois, restored wetlands are used to improve water quality in streams degraded by agriculture and urban development. Using freshwater wetlands to reduce nitrogen loading to lakes and rivers is well documented; however, there are fewer studies addressing their use to remove phosphorous. In 1998, a systematic water quality monitoring project was begun at Prairie Wolf Slough Wetland Demonstration Project, a restored palustrine emergent marsh wetland located on an abandoned farm field north of Chicago. The wetland drains 98 ha of mixed land uses into the Chicago River. Our objectives were to assess spatial and temporal variations in total suspended solids, soluble reactive and total phosphorous concentrations, and mass loadings and compute a mass balance and retention efficiency for these constituents. Water sampling was conducted from 1998 to 2003. In 2004, soil samples were collected from the marsh and an adjacent abandoned farm site and analyzed for soil test (Bray) phosphorus. The marsh effectively traps suspended solids but acts as a source of soluble reactive and total phosphorous to the river both during the growing and nongrowing seasons. Net export of phosphorous from the wetland was likely due to mobilization of orthophosphate as a result of anoxic conditions produced during inundation events. Often little consideration is given to the link between soil and water quality when locating restoration sites. Our study adds to a growing body of literature that clearly demonstrates the need for both soil and water quality assessments in wetland restoration planning, design, and monitoring.
... A new concept of receiving environmental quality market credits to account for reductions of agricultural N losses and prevention of their transport into water bodies has been proposed (Greenhalch and Sauer, 2003;Ribaudo et al., 2005;Glebe, 2006;Hey, 2002;Hey et al., 2005;Lal et al., 2009). However, since quantification of N losses is so complex, and the pathways for losses of nitrogen are so numerous, it is difficult to determine how management practices can reduce the losses of nitrogen by a given amount (Delgado, 2002) and how much can be traded in a given water and air quality market without the use of a robust tool (Delgado et al., 2008a). ...
... Delgado et al. (2008b) Delgado et al. (2008b) considered that nutrient managers may also be interested in total nitrogen losses. Although management of denitrification is a good approach to reducing NO 3 -N losses to water bodies (Hunter 2001;Mosier et al. 2002, Hey, 2002Hey et al., 2005), nutrient managers may be able to reduce N inputs if the losses due to denitrification are reduced and nitrogen use efficiencies are increased (Mosier et al., 2002). The NTT calculates N 2 -N denitrification (∆ N 2 -N) and total N losses (NTT-DNL tot ) with Equation 21 and 22, respectively. ...
... Several researchers have proposed the concept of using payments as part of an ecosystem services payment system in an environmental trading/water quality trading program to reduce the negative effects of reactive nitrogen in the environment. [19][20][21][22][23] Hey and Hey et al. [19,21] recommended the strategic placement of wetlands across the Mississippi watershed that could be used as filters to remove nitrate as it enters these wetlands to reduce the transport of nitrogen to the Gulf of Mexico and have farmers receive environmental payments for developing wetlands for their farms to remove the nitrate. This approach is one of a series of precision conservation approaches that could be used with other conservation practices that could be set up strategically in fields and the landscape to increase the efficiency of conservation practices such as sediment traps, riparian buffers and denitrification traps to remove nitrate, phosphorus and sediment from water traveling to the Mississippi River and water bodies. ...
... Several researchers have proposed the concept of using payments as part of an ecosystem services payment system in an environmental trading/water quality trading program to reduce the negative effects of reactive nitrogen in the environment. [19][20][21][22][23] Hey and Hey et al. [19,21] recommended the strategic placement of wetlands across the Mississippi watershed that could be used as filters to remove nitrate as it enters these wetlands to reduce the transport of nitrogen to the Gulf of Mexico and have farmers receive environmental payments for developing wetlands for their farms to remove the nitrate. This approach is one of a series of precision conservation approaches that could be used with other conservation practices that could be set up strategically in fields and the landscape to increase the efficiency of conservation practices such as sediment traps, riparian buffers and denitrification traps to remove nitrate, phosphorus and sediment from water traveling to the Mississippi River and water bodies. ...
... Continuing on the topic of restoring the agricultural lands in the Mississippi River Basin, Hey et al. (2005) present an intriguing concept of "nitrogen farming" as a means to economically encourage agriculture in the Midwest to create wetlands and other methods to reduce nitrogen to the Gulf of Mexico. They argue that credit could be given to farmers for storing floodwaters as well as removing nitrogen, phosphorus, carbon, pesticides, sediments, and other constituents and that this trading could be done in the marketplace, lessening farmer's dependence on government subsidies while providing relieve for nonpoint source pollution and flooding. ...
... Wetlands can also be constructed to remove nitrogen and phosphorus from farm drainages before they enter streams (Kovacic et al., 2006). Such practices could become more widespread through direct incentive payments to farmers who use them, or by development of nutrient trading markets, similar to carbon trading markets (Hey et al., 2005). ...
Article
The articles in this volume of Hydrobiologia commemorate the 40th anniversary of the Mississippi River Research Consortium by synthesizing research and monitoring conducted on the river over the past 40years. This article briefly describes the recent history of development (since 1866) of the river and the programs that currently support monitoring, research, and rehabilitation of the river. These programs have generated much of the information reported in the articles, which cover hydrology and geomorphology, contaminants, nutrients, plants, reptiles and amphibians, food webs, and concepts of river ecology. The Upper Mississippi River is still responding to changes that occurred 70 or more years ago (construction of navigation dams, leveeing of the floodplains, and intensification of agriculture in the catchment) and to new stressors (climate change, invasive species, hormone-disrupting chemicals). Nevertheless, the river continues to attract 12 million visitors per year along the scenic Great River Road, hosts 36% of all the migrating ducks in the contiguous United States, and is home to 129 native species of freshwater fishes. The biological productivity and diversity of the river are likely to be maintained and even enhanced if the following occur: (1) planned rehabilitation efforts are coupled with hypothesis testing (adaptive environmental assessment and management); (2) sampling is extended beyond the six river reaches that are currently monitored intensively; (3) new sensor networks are developed and deployed; (4) water quality is protected by better controls on nonpoint sources and better testing of new chemicals before they are widely introduced; and (5) ways are found to engage multidisciplinary teams of academic scientists around the world, as well as agency scientists and managers, in cooperative efforts to better understand and manage large, complex, dynamic floodplain–river ecosystems.
... Nevertheless, some crop loss will likely occur during extreme peak flow events. To meet the environmental goals of nutrient attenuation, Hey et al. (2005) have suggested that producers be compensated for nutrient farming (the removal of excess nutrients from streams via riparian wetlands). Because of the uncertainty associated with wetland phosphorous cycling and potential TP losses to streams, riparian interception-wetlands must provide enough hydraulic storage for evapotranspiration to be the dominant export pathway. ...
Article
Full-text available
Riparian wetlands have multiple source waters that require understanding to effectively manage water quantity and quality. Source waters were determined in an interception-wetland located a relatively flat clayey till terrain in southern Minnesota. Data loggers were used to measure precipitation, water stage from monitoring wells and a tile-drain outlet. Over 70 oxygen (δ18O), hydrogen (δD) and geochemical water samples were collected from seven locations over different seasons (9 events) from 1996 to 1999. Results indicate the dominant source water input to the wetland was drained shallow groundwater beneath intensively managed cropland (P=0.000). Evapotranspiration was the dominant export pathway. Nitrate–nitrogen (NO3-N) concentrations significantly decreased (P=0.000) in the cattail-willow portion of the wetland. Total phosphorous (TP) concentrations were relatively high in the grass portion of the wetland (673±549μgL−1), and relatively low in the cattail-willow portion of the wetland (139±85μgL−1) because source waters were low in TP. Overall, the interception-wetland design limited out-of-bank flooding, yet allowed sufficient gradient between the cropland and the wetland outlet to minimize potential crop damage and provide hydraulic storage for nutrient attenuation.
... Therefore, mathematical difference between the base scenario and the new N management scenario is assessed by adding individual pathway NTT-DNL reac values. Since denitrification (N 2 -N) losses could be beneficial to the environment (Mosier et al., 2002;Hunter, 2001;Hey, 2002;Hey et al., 2005), we calculated the NTT mathematical difference in reactive N losses (NTT-DNL reac ) using Eqs. (1)-(6). ...
Article
Nitrogen (N) losses from agriculture often contribute to reduced air, groundwater, and surface water quality. The minimization of these N losses is desirable from an environmental standpoint, and a recent interest in discounted reductions of agricultural N losses that might apply to a project downstream from an agricultural area has resulted in the concept of N credits and associated N trading. To help quantify management-induced reductions in N losses at the farm field level (essential components of a Nitrogen Trading Tool), we defined a Nitrogen Trading Tool difference in reactive N losses (NTT-DNLreac) as the comparison between a baseline and new management scenarios. We used a newly released Windows XP version of the Nitrogen Losses and Environmental Assessment Package (NLEAP) simulation model with Geographic Information System (GIS) capabilities (NLEAP-GIS) to assess no-till systems from a humid North Atlantic US site, manure management from a Midwestern US site, and irrigated cropland from an arid Western US site. The new NTT-DNLreac can be used to identify the best scenario that shows the greatest potential to maximize field-level savings in reactive N for environmental conservation and potential N credits to trade. A positive NTT-DNLreac means that the new N management practice increases the savings in reactive N with potential to trade these savings as N credits. A negative number means that there is no savings in reactive N and no N available to trade. The new NLEAP-GIS can be used to quickly identify the best scenario that shows the greatest potential to maximize field-level savings in reactive N for environmental conservation and earning N credits for trade.
... Field and off-site parameters need to be considered when deciding on nitrogen management practices. Off the field practices, such as buffers, can contribute to reduce N losses to the environment (Dosskey et al., 2005;Hefting et al., 2005;Hey et al., 2005). Shaffer and Delgado (2002) and Delgado et al. (2006) recommended that a practical Tier-1 N-Index tool should be able to integrate best management practices with ecological engineering principles and practices such as use of buffers, account for distance to water bodies, deeper rooting systems, distance to aquifers, and others, to help separate and rank the potential effects of nitrogen management. ...
Article
Nitrogen (N) losses from agriculture are negatively impacting groundwater, air, and surface water quality. New tools are needed to quickly assess these losses and provide nutrient managers and conservationists with effective tools to assess the effects of current and alternative management practices on N loss pathways. A new N-Index tool was developed in spreadsheet format, allowing prompt assessments of management practices on agricultural N losses. The N-Index tool was compared with experimental field data and shown to estimate the effects of management practices on N loss pathways (probability, P < 0.001). The N-Index correctly assessed the nitrate nitrogen (NO3-N) leaching losses when tested against measured NO3-N leaching data and atmospheric N losses collected over multiple years (annual basis) and locations. The N-Index tool was developed with international cooperation from several countries and there is potential to use this tool at the international level.
... For example, educating the local community about ecosystem conservation is important in order to heighten the local awareness and understanding of environmental protection. The creation of a nitrogen market in which nitrogen credits can be traded would be an innovative economic incentive to encourage local landowners to leave their wetlands undeveloped [22], which has yet to be considered in Korea. It is important to remember that suggestions like this should be adapted to the specific social context of the relevant region. ...
Article
The history of Korean tidal flat management and the process for designating Coastal Wetland Protected Areas (CWPAs) are described. Korean coastal wetlands have a long history of intensive use through reclamation for agricultural and industrial uses in the 20th century. Recently, the management policy is shifting away from intensive use towards the conservation of wetlands. This shift is caused by increasing public awareness of the value of wetlands and strong institutional support from the government. Since the Wetlands Conservation Act was passed in 1999, a total of twelve CWPAs have been designated through both top-down and bottom-up processes. Three designation paths are classified based on the relevant drivers, namely government-driven designations (seven CWPAs), local community driven designations (three CWPAs), and conflict resolution (trade-offs) driven designation (two CWPAs). The lessons learned from the designation of Korean CWPAs is that diversification of designation process could facilitate voluntary participation of local stakeholders and thereby enhance the chance of successful implementation of wise use strategy of tidal flats.Research highlights►Korean wetland management policy shift in the mid of 1990s. ►Twelve Coastal Wetland Protected Areas have been designated. ►Three designation paths are observed in Korean wetland management. ►Diversification of designation process could enhance MPA success.
... Quantitative performance information is required so that farmers, agricultural advisors, and industry and regulatory agencies can assess the applicability and cost-eff ectiveness of wetlands in comparison to other mitigation options available to help achieve water quality targets. Th is information also underpins the potential development of nutrient farming and trading programs that harness and value the ecosystem services provided by wetlands (Craft, 2006;Hey et al., 2005). ...
Article
Subsurface tile drain flows can be a major s ource of nurient loss from agricultural landscapes. This study quantifies flows and nitrogen and phosphorus yields from tile drains at three intensively grazed dairy pasture sites over 3- to 5-yr periods and evaluates the capacity of constructed wetlands occupying 0.66 to 1.6% of the drained catchments too reduce nutrient loads. Continuous flow records are combined with automated flow-proportional sampling of nutrient concentrations to calculate tile drain nutrient yields and wetland mass removal rates. Annual drainage water yields rangedfrom 193 to 564 mm (16-51% of rainfall) at two rain-fed sites and from 827 to 853 mm (43-51% of rainfall + irrigation) at an irrigated site. Annually, the tile drains exported 14 to 109 kg ha(-1) of total N (TN), of which 58 to 90% was nitrate-N. Constructed wetlands intercepting these flows removed 30 to 369 gTN m(-2) (7-63%) of influent loadings annually. Seasonal percentage nitrate-N and TN removal were negatively associated with wetland N mass loadings. Wetland P removal was poor in all wetlands, with 12 to 115% more total P exported annually overall than received. Annually, the tile drains exported 0.12 to 1.38 kg ha of total P, of which 15 to 93% was dissolved reactive P. Additional measures are required to reduce these losses or provide supplementary P removal. Wetland N removal performance could be improved by modifying drainage systems to release flows more gradually and improving irrigation practices to reduce drainage losses.
... Other forms of long-term investment would consequently be possible if the options were attractive and directed toward the business, rather than to the landowner as an individual. This approach requires a change of view on the part of authorities, away from the perspective of landowners as those who only need to be informed of what to do (Burgess et al., 2000) to professional providers of ecosystem services (Hey et al., 2005). A change of identity among landowners is correspondingly needed (Burton, 2004), from seeing themselves as unfairly treated strugglers to being entrepreneurs within the ecosystem service market. ...
... Humans cleared forests, broke sod, and drained wetlands to clear land and facilitate farming. An unintended consequence of this land conversion was degraded water quality, flood damage, diminished biodiversity, and radically altered regional hydrology (Prince 1997, Hey et al. 2005. Because hydrology determines the location of wetlands and their structural and functional properties, agricultural expansion has caused not only an enormous loss of wetland acreage, but has also compromised the ability of existing wetlands to provide their characteristic ecosystem services (Zedler 2003b). ...
... Perennial-based agroecosystems well suited for this region include woody and herbaceous perennial polycultures (Tilman et al. 2006), agroforestry systems (Jorgensen et al. 2005), and managed wetlands (Hey et al. 2005). There is mounting evidence that such agroecosystems, integrated in a welldesigned landscape, can produce agricultural commodities abundantly and profitably while producing nonmarket public goods and services more effectively than annual systems such as corn (Zea mays L.) and soybean (Glycine max L. Merr.). ...
Article
Full-text available
Multifunctional agriculture (MFA) enhances the quality and quantity of benefits provided by agriculture to society, by joint production of both agricultural commodities and a range of ecological services. In developed countries, new agroecosystem designs for MFA are appearing rapidly, but adoptions are limited. We present a heuristic strategy for increasing the adoption of MFA through development of new enterprises that enable farmers to profit from production of both agricultural commodities and ecological services. We propose that such enterprises can arise through feedback between social and biophysical systems operating across a range of scales. Such feedback depends on coordinated innovation among economic actors in a range of interdependent social sectors, supported by new “subsystems” that produce site-specific agroecological knowledge, and by change in the encompassing “supersystem” of public opinion and policy. This strategy can help guide efforts to increase the adoption of MFA.
... The realization that nature sustains economies is, however, not new to ecologists. Leopold (1949) wrote on that theme, and subsequent authors have tried to impress it upon a broad audience (Hey et al., 2005, Hackney, 2000, Gren, 1995and Storer, 1968. Ecologists have subsequently tried to develop a compelling empirical basis for the worth of natural capital that economists would accept (Odum, 1994 andWestman, 1977). ...
... Restoring prairie for biofuel use can produce a valuable energy feedstock while offering valuable ecosystem services (Clergue et al., 2005;Foley et al., 2005). These ecosystem services include pollinator habitat for service to nearby crop fields (Greenleaf and Kremen, 2006) and mitigation of agricultural runoff from traditional farming by reducing flow volumes and increasing nutrient use opportunity (Huggins et al., 2001), akin to similar services provided by wetlands (Hey et al., 2005). ...
Article
Transportation biofuel production in the United States is currently dominated by ethanol from the grain of maize and, to a much lesser extent, biodiesel from soybeans. Although using these biofuels avoids many of the environmentally detrimental aspects of petroleum-based fossil fuels, biofuel production has its own environmental costs, largely related to fossil fuel use in converting crops to biofuels and crop cultivation itself, including ecological damages caused by nitrogen and phosphorus fertilizers, pesticides, and erosion. A new generation of biofuels derived from lignocellulosic sources offers greatly reduced environmental impacts while potentially avoiding conflicts between food and energy production. In particular, diverse mixtures of native prairie species offer biomass feedstocks that may yield greater net energy gains than monoculture energy crops when converted into biofuels, while also providing wildlife habitat and enriching degraded soils through carbon sequestration and nitrogen fixation. Ultimately, as demand for both food and energy rise in the coming decades, greater consideration will need to be given to how land can best be used for the greater benefit of society.
... Some researchers have proposed recommendations for specific industries, such as agriculture and fisheries. Hey and others (2005) proposed stimulating and funding wetland restoration by creating nutrient removal credits (i.e., credits that can be bought or sold on an open market or through long-term contracts to improve water quality) and a ''nutrient farming'' strategy based on nitrogen credits. Páez-osuna (2001) analyzed choices regarding the siting and operation of shrimp aquaculture, assessed the environmental impacts of shrimp aquaculture, and discussed alternatives for mitigating the problems. ...
Article
Wetland protection and utilization sometimes appear to be in conflict, but promoting the wise use of wetlands can solve this problem. All countries face the challenge of sustainable development of wetlands to a greater or lesser extent, but the problem is especially urgent in developing countries, such as China, that want to accelerate their economic development without excessive environmental cost. Chinese wetlands contribute greatly to economic development, but improper use of these natural resources has endangered their existence. It is thus necessary to provide scientific guidance to managers and users of wetlands. In this paper, we analyze the present status of Chinese wetland protection and utilization, and discuss problems in six categories: a lack of public awareness of the need for wetland protection; insufficient funding for wetland protection and management; an imperfect legal system to protect wetlands; insufficient wetland research; lack of coordination among agencies and unclear responsibilities; and undeveloped technologies related to wetland use and protection. The wise use of Chinese wetlands will require improvements in four main areas: increased wetland utilization research, scientific management of wetland utilization, improved laws and regulations to protect wetlands, and wider dissemination of wetland knowledge. Based on these categories, we propose a framework for the optimization of wetland use by industry to provide guidance for China and other countries that cannot sacrifice economic benefits to protect their wetlands.
... Continuing on the topic of restoring the agricultural lands in the Mississippi River Basin, Hey et al. (2005) present an intriguing concept of "nitrogen farming" as a means to economically encourage agriculture in the Midwest to create wetlands and other methods to reduce nitrogen to the Gulf of Mexico. They argue that credit could be given to farmers for storing floodwaters as well as removing nitrogen, phosphorus, carbon, pesticides, sediments, and other constituents and that this trading could be done in the marketplace, lessening farmer's dependence on government subsidies while providing relieve for nonpoint source pollution and flooding. ...
... A carbon tax should also lead to lower carbon emissions due to lower consumer demand and the development of efficient alternative fuel sources. In addition, a wetland subsidy would promote additional restoration and creation efforts on the part of state and local governments, and private landowners, who wish to capture a portion of the subsidy and gain economically from increased productivity on their lands (Hey et al. 2005). This would lead to increased carbon sequestration. ...
... In its present state of excess, nitrogen is instrumental in creating the Dead Zones in the Gulf of Mexico. However, a large scale study of these new functions for floodplain land has been proposed for a site in the Illinois River basin (Hey et al., 2005b). According to the nutrient farming model, a landholder could sell or trade the water quality improvement "credits" to municipal and industrial wastewater treatment facilities that discharge excess nutrients into the receiving waters. ...
... Commercialization of the technology is under way by HydroMentia, Inc., which is currently building and operating ATS on the hectare scale in Florida. Use of ATS for water quality improvement represents a kind of "nutrient farming" (Hey 2002, Hey et al. 2005, with clean water as a primary output. Values from byproducts of the biomass of algae grown on ATS need to be developed, but these will accrue in addition to water quality improvement values. ...
Article
Full-text available
As human populations have expanded, Earth's atmosphere and natural waters have become dumps for agricultural and industrial wastes. Remediation methods of the last half century have been largely unsuccessful. In many US watersheds, surface waters are eutrophic, and coastal water bodies, such as the Chesapeake Bay and the Gulf of Mexico, have become increasingly hypoxic. The algal turf scrubber (ATS) is an engineered system for flowing pulsed wastewaters over sloping surfaces with attached, naturally seeded filamentous algae. This treatment has been demonstrated for tertiary sewage, farm wastes, streams, and large aquaculture systems; rates as large as 40 million to 80 million liters per day (lpd) are routine. Whole-river-cleaning systems of 12 billion lpd are in development. The algal biomass, produced at rates 5 to 10 times those of other types of land-based agriculture, can be fermented, and significant research and development efforts to produce ethanol, butanol, and methane are under way. Unlike with algal photobioreactor systems, the cost of producing biofuels from the cleaning of wastewaters by ATS can be quite low.
... Humans cleared forests, broke sod, and drained wetlands to clear land and facilitate farming. An unintended consequence of this land conversion was degraded water quality, flood damage, diminished biodiversity, and radically altered regional hydrology (Prince 1997, Hey et al. 2005. Because hydrology determines the location of wetlands and their structural and functional properties, agricultural expansion has caused not only an enormous loss of wetland acreage, but has also compromised the ability of existing wetlands to provide their characteristic ecosystem services (Zedler 2003b). ...
Article
Full-text available
The Glaciated Interior Plains historically supported a broad variety of wetland types, but wetland losses, primarily due to agricultural drainage, range from 50% to 90% of presettlement area. Wholesale land use change has created one of the most productive agricultural regions on earth, but wetland conversion has also led to the loss of the ecosystem services they provide, particularly water quality improvement, flood de-synchronization, carbon sequestration, and support of wetland-dependent species (biodiversity). Nearly three-quarters of the Glaciated Interior Plains fall within the Mississippi River drainage basin, where the combination of extensive tile drainage and fertilizer use has produced watersheds that contribute some of the highest nitrogen yields per acre to the Mississippi River. Wetland conservation practices implemented under Farm Bill conservation programs have established or involved management of nearly 110000 ha of wetlands, riparian zones, and associated ecosystem services over the period 2000—2007. We estimated the cumulative ability of these conservation practices to retain sediment, nitrogen, and phosphorus in Upper Mississippi River Basin watersheds. Estimated retention amounts to 1.0%, 1.5%, and 0.8% of the total N, sediment, and P, respectively, reaching the Gulf of Mexico each year. If nutrient reduction is estimated based on the quantity of nutrients exported from the Glaciated Interior Plains region only, the numbers increase to 6.8% of N, 4.9% of P, and 11.5% of sediment generated in the region annually. On a watershed basis, the correlation between the area of wetland conservation practices implemented and per-hectare nutrient yield was 0.81, suggesting that, for water quality improvement, conservation practices are successfully targeting watersheds that are among the most degraded. The provision of other ecosystem services such as C sequestration and biodiversity is less well studied. At best, implementation of wetland and riparian conservation practices in agricultural landscapes results in improved environmental quality and human health, and strengthens the rationale for expanding conservation practices and programs on agricultural lands.
... In its present state of excess, nitrogen is instrumental in creating the Dead Zones in the Gulf of Mexico. However, a large scale study of these new functions for floodplain land has been proposed for a site in the Illinois River basin (Hey et al., 2005b). According to the nutrient farming model, a landholder could sell or trade the water quality improvement "credits" to municipal and industrial wastewater treatment facilities that discharge excess nutrients into the receiving waters. ...
... The practice of strategically placing wetlands across the landscape to remove nitrogen has been referred to as nutrient farming (Hey et al., 2005;Berry et al., 2003;Berry et al., 2005;and Tomer, 2010). To be effective, the wetland must be placed at the bottom of a wetland watershed that is large enough to supply enough water to maintain a healthy ecosystem and has nitrogen loadings that are of concern. ...
... Field and off-site parameters need to be considered when deciding on nitrogen management practices. Off the field practices, such as buffers, can contribute to reduce N losses to the environment (Dosskey et al., 2005;Hefting et al., 2005;Hey et al., 2005). Shaffer and Delgado (2002) and Delgado et al. (2006) recommended that a practical Tier-1 N-Index tool should be able to integrate best management practices with ecological engineering principles and practices such as use of buffers, account for distance to water bodies, deeper rooting systems, distance to aquifers, and others, to help separate and rank the potential effects of nitrogen management. ...
Conference Paper
Nitrogen inputs significantly contribute to increased yields, food security, and the economic viability of agricultural systems. This is due to the fact that most agricultural systems are nitrogen deficient, and nitrogen is essential to so many physiological functions in plants. One factor that complicates nitrogen management is that this nutrient is very dynamic and can be lost from the system in many different ways, such as via denitrification, leaching, and volatilization. The rate of losses from the system is a function of many physical, chemical, climatic and biological factors. This complexity makes the management of nitrogen to maximize yields while reducing the risk of reactive nitrogen losses to the environment a difficult task. The Nitrogen Index can aid in the assessment of risk of nitrogen losses to the environment. This tool has been validated and calibrated across several regions and countries, and it has been found to be capable of quickly assessing the risk of nitrogen losses. The tool can currently be used in the English and Spanish languages, and will soon be available in Portuguese. The tool may also become available in additional languages with future releases. The tool is being used across the USA (e.g., it is being used by NRCS in Kentucky as part of the state's nutrient management plans), and in Mexico, Ecuador, and other countries. The tool has new features such as a Phosphorus Index and the capability to quickly estimate nitrogen use recommendations for a given site. It can also now be used to assess the effects of management on N2O emissions and carbon sequestration equivalents. Examples will be presented on the potential to use this tool to quickly assess the risk of nitrogen losses to the environment, to reduce nitrate leaching and N2O emissions, and to increase nitrogen use efficiency.
... N utrient management, including management of nitrogen (N) inputs, was a key part of the Green Revolution, which increased global agricultural production and helped feed the world in the latter half of the twentieth century. While N is often applied to increase yields, and is indeed essential to meet the increased production demand that inevitably follows population growth, an extensive number of studies from regions throughout the globe have reported negative impacts related to N losses to the environment (Smith et al. 2018;Follett and Walker 1989;Hey 2002;Hey et al. 2005;Greenhalch and Sauer 2003;Delgado and Follett 2010;Juergens-Gschwind 1989;Dubrovsky et al. 2010;Glebe 2006), particularly when N was applied at excessive rates, allowing much of the unused N to quickly escape agroecosystems via atmospheric, surface runoff, and/or leaching pathways. Among the negative effects reported by these studies were contributions to the development of hypoxic zones and algae blooms; direct and indirect losses of nitrous oxide (N 2 O), a greenhouse gas (GHG) that exacerbates a changing climate; nitrate (NO 3 -) leaching losses that can negatively impact groundwater and surface water quality; and other negative environmental impacts. ...
... Rather they noted that at the farm level, wetland construction was generally more expensive than other conservation measures. However others have found that wetlands could be more cost-effective than fertilizer management on a regional level, as shown in Hey et al. (2005) where the feasibility of restored wetlands as a mitigation tactic in a nitrogen market was investigated. The benefits of wetlands construction include: excess nutrient removal, floodwater storage and wildlife habitats. ...
... Mississippi (Hey et al., 2005) Rivers, which may have thus diminished the role of point source pollution in these rivers. Similar to our study, Zhang (2017) showed a decrease in c-Q slopes with increase in discharge in the Potomac. ...
Article
Full-text available
Little is known about temporal variability in nitrate concentration responses to changes in discharge on intraannual time scales in large rivers. To investigate this knowledge gap, we used a six-year data set of daily surface water nitrate concentration and discharge averaged from near-continuous monitoring at U.S. Geological Survey gaging stations on the Connecticut, Potomac, and Mississippi Rivers, three large rivers that contribute substantial nutrient pollution to important estuaries. Interannually, a comparison of nitrate concentration-discharge (c-Q) relationships between a traditional discrete grab sample data set and the near-continuous data set revealed differing c-Q slopes, which suggests that sample frequency can impact how we ultimately characterize hydrologic systems. Intraannually, we conducted correlation analyses over 30-day windows to isolate the strength and direction of monthly c-Q relationships. Monthly c-Q slopes in the Potomac were positive (enrichment/mobilization response) in summer and fall and negative (dilution response) and weakly chemostatic (nonsignificant near-zero c-Q slope) in winter and spring, respectively. The Connecticut displayed a dilution response year-round, except summer when it was weakly chemostatic. Mississippi c-Q slopes were weakly chemostatic in all seasons and showed inconsistent responses to discharge fluctuations. The c-Q dynamics in the Potomac and Connecticut were correlated (R > 0.3) to river temperature, flow percentile, and calendar day. Minimal correlation in the Mississippi suggests that the large basin area coupled with spatiotemporally variable anthropogenic forcings from substantial land use development created stochastic short-term c-Q relationships. Additional work using high-frequency sensors across large river networks can improve our understanding of spatial source input dynamics in these natural-human coupled systems.
... Various strategies to capture these releases have been proposed, among which "nutrient farming" (Hey, Urban, and Kostel 2005) has shown promise. One type of nutrient farming involves the capture of nutrients in a wetland to stimulate the growth of wetland plants that uptake N and P while they grow. ...
Conference Paper
Full-text available
Midwestern states have agreed to reduce nutrient releases to combat Gulf of Mexico hypoxia by focusing on the approximately 80% of N and 50% of P loading resulting from agriculture. In support of this effort, we are working with The Wetlands Initiative to develop “Pocket Wetlands” to capture and treat drain tile water by microbial denitrification and nutrient sequestration. Two wetlands were built, W1 in 2015 and W2 in 2017, in high-yield corn/soybean cropland in IL. Inlet and outlet flow and nutrient data have been used to assess treatment performance and learn lessons about construction and operation to increase nutrient removal. NO3⁻-N levels averaged 11.7 mg/l, and SRP averaged 0.18 mg/l in W1 during 2016 with a DIN/SRP ratio >65. Overall, 1100 kg of N was removed in 2016 from W1, but with relatively low efficiency. In the second year, W1 nitrate removal efficiency increased significantly with total removal of 1700 kg of N and 200 kg of P. Lessons learned from the operation of W1 have been employed in the construction and operation of wetland W2. Data from initial operation in W2 demonstrate the importance of proper conditions to support the microbial denitrification process.
Article
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A U.S. farm policy shift to joint production of commodities and ecological services will advance sustainable agriculture.
Article
Feuchtgebiete sind Ökosysteme, die durch die Anwesenheit von Wasser, spezielle Bodenverhältnisse und eine besondere Vegetationszusammensetzung geprägt sind. Sie zählen zu den am stärksten bedrohten Ökosystemen der Erde. Im Verlauf des 20. Jahrhunderts nahm weltweit sowohl ihre Fläche als auch ihre Qualität (bezüglich Artenvielfalt etc.) stark ab. Viele von Wasser beeinflusste Flächen, v.a. in Flussauen, wurden gezielt entwässert, um sie für Siedlungen, Industrie oder wegen der fruchtbaren Böden für intensive Landwirtschaft nutzbar zu machen. Im natürlichen Zustand stellen Flächen mit Feuchtgebieten allerdings ebenfalls wertvolle ökonomische Ressourcen dar (u.a. dienen sie dem Hochwasserschutz, der Nährstoffspeicherung, Erholung und Naturschutz), so dass eine Umwandlung bzw. Degradation dieses Naturkapitals oft nicht zu einer wirklichen Steigerung der gesellschaftlichen Wohlfahrt führt. Im Rahmen der Betrachtung der Problematik der Erhaltung und der Rückgewinnung von Überschwemmungsflächen, welche im Fokus dieser Arbeit stehen, werden Flächennutzungskonflikte in Flussgebieten in Verbindung mit den Schwierigkeiten des institutionellen Rahmens deutscher Bodenmärkte untersucht. Zur Schärfung der Argumentation wird ein extremes Beispiel für die Rückgewinnung von Feuchtgebieten - der Abbruch einer Siedlung im potenziellen Überschwemmungsbereich eines Flusses - herausgegriffen. Eine abstrakte Einheitssiedlung sowie tatsächliche Umsiedlungen dienen der Ermittlung der volkswirtschaftlichen Kosten eines solchen Vorhabens, welche dann den in anderen Studien erfassten Nutzen von Feuchtgebieten gegenübergestellt werden können. Die Berechnungen zeigen, dass es schon allein unter Berücksichtigung der zum Schutz der Siedlung notwendigen Erhaltungs- und Erneuerungskosten eines Hochwasserschutzdeiches ab einem bestimmten Zeitpunkt empfehlenswert sein kann, diese Siedlung nicht weiter aufrecht zu erhalten. Der Nutzen des zu erstellenden Feuchtgebietes muss hier gar nicht bekannt sein, um eine Entscheidung zugunsten einer Absiedlung zu treffen (allerdings: starke Sensitivität gegenüber den verwendeten Diskontsätzen). Daneben kann gezeigt werden, dass ein optimaler Zeitpunkt für Abbruch bzw. Umsiedlung ermittelt werden kann, bei welchem die Differenz zwischen Nutzen und Kosten des Vorhabens maximal ist. Wetlands are highly productive, multifunctional ecosystems, providing a large number of products and services to mankind such as nutrient retention, flood protection and conservation of biodiversity. However, in the course of the 20th century quantity and quality (in terms of biodiversity) of these ecosystems declined. The worldwide wetland area has been receded to 50 % of the pristine extent despite their relevance. For parts of the world with high density settlements as Germany for the considered problem the importance of the institutional framework particularly with regard to land markets can be shown. These markets are affected by many regulations by law, which contribute to a distortion of land prices offering incentives to convert wetlands into intensively used fields or defining river lowlands as profitable building land. In the framework of a case study the costs of reversing the process of wetland destruction, more precisely the opportunity costs of displacement of a settlement in favor of reestablishing wetlands and simultaneously abating damages from floods are examined in consideration of institutions and regulations. In this analysis the influence of regulations on land markets on the costs of nature protection as well as on the costs of ecological measures of flood protection (flooding areas) becomes apparent.
Article
Vegetable growing leads to high nitrogen emissions. In the Netherlands, nitrogen emissions can hardly be reduced by reducing fertilization without risks for yield and quality loss. An alternative measure to reduce emissions is to collect nitrate-rich drain water and remove nitrate from the drain water in constructed wetlands. This was tested in three different types of constructed wetlands at an experimental farm in the SE of the Netherlands: (1) a surface flow system (SF) planted with Common reed, (2) a horizontal subsurface flow system with Common reed (SSF-reed) and (3) a horizontal subsurface flow system filled with straw (SSF-straw). The water discharge into the wetlands is adjusted to the nitrate removal capacity of the wetlands. In- and outlet concentrations of nitrogen and other nutrients were measured every two weeks since December 2005. Collected water from pipe drains contained on average 30 mg N L-1. The mean N removal was 58% in SF (1655 kg N ha-1 year-1), 25% in SSF-reed (1447 kg ha-1 year-1) and 63% in SSF-straw (3622 kg N ha-1 year-1). SF and SSF-straw are functioning well. In SSF-reed, the amount of carbon seems to be insufficient to sustain nitrogen reduction. Disadvantage of SSF-straw is the negative removal rate of phosphorus (mean 16 kg ha-1). With a removal rate of about 60% within the system, about 20% of the leached nitrogen from the vegetable fields could be removed: about two-third of the leached water is collected in drains and half of the nitrate-rich drain water is collected for purification. The cost effectiveness (expressed as € per kg N removed) ranged between € 52 and € 104 kg-1 N for SF, between € 29 and 58 kg-1 N for SSF-straw and between € 161 and € 322 kg-1 N for SSF-reed. Cost reduction is possible by combining with other functions as water storage and nature development
Article
Multifunctional agriculture (MFA) enhances the quality and quantity of benefits provided by agriculture to society, by joint production of both agricultural commodities and a range of ecological services. In developed countries, new agroecosystem designs for MFA are appearing rapidly, but adoptions are limited. We present a heuristic strategy for increasing the adoption of MFA through development of new enterprises that enable farmers to profit from production of both agricultural commodities and ecological services. We propose that such enterprises can arise through feedback between social and biophysical systems operating across a range of scales. Such feedback depends on coordinated innovation among economic actors in a range of interdependent social sectors, supported by new "subsystems" that produce site-specific agroecological knowledge, and by change in the encompassing "supersystem" of public opinion and policy. This strategy can help guide efforts to increase the adoption of MFA. © 2010 by American Institute of Biological Sciences. All rights reserved.
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Limitations and disadvantages of artificial sweeteners in the food and beverage products act as an incentive for paying attention to the extraction and purification of natural sweeteners. Aqueous two-phase systems (ATPSs) are believed to be a desirable method for the extraction and separation of biomolecules. In recent years, researchers have focused on the use of innocuous, benign components having potential to form ATPSs. In this research, Choline Chloride, as a biocompatible and nutritious constituent, has been utilized to establish an ATPS performing the extraction of stevioside. To assess the efficiency of the ATPS composed of choline chloride and potassium phosphate, the partitioning of stevioside was explored. The effects of such parameters as the weight percents of choline chloride and potassium phosphate on the partitioning of stevioside were studied. All experiments were conducted at four temperatures of 298 K, 303 K, 308 K, and 313 K. Also, the effect of pH on the partitioning of stevioside was investigated. Different regression models were adopted to correlate the empirical results of the stevioside partition coefficient, and through statistical analyses the most reliable regression model was chosen.
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This chapter proposes an integrative and heuristic strategy - a 'theory of change' - to address interlocking challenges of climate change and sustainable management of agriculture and bioresources. It aims to increase the multifunctionality of agriculture in the Upper Midwest region of the USA by pursuing change at three distinct levels of integration. The chapter first describes the central system level, which addresses development of new economic opportunities and related systems of management and policy, for farmers of multifunctional agroecosystems. Next, it portrays a pivotal subsystem of the enterprise development model, agroecological partnerships, that produce knowledge needed for multifunctional agriculture (MFA). Third, the chapter describes how social values shape the supersystem of public opinion and policy. The chapter finally presents a case study - the Koda Energy Fuelshed project - which outlines the challenges in realizing the potential of MFA.
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Vegetable growing leads to high nitrogen emissions. In the Netherlands, nitrogen emissions can hardly be reduced by reducing fertilization without risks for yield and quality loss. An alternative measure to reduce emissions is to collect nitrate-rich drain water and remove nitrate from the drain water in constructed wetlands. This was tested in three different types of constructed wetlands at an experimental farm in the SE of the Netherlands: (1) a surface flow system (SF) planted with Common reed, (2) a horizontal subsurface flow system with Common reed (SSF-reed) and (3) a horizontal subsurface flow system filled with straw (SSF-straw). The water discharge into the wetlands is adjusted to the nitrate removal capacity of the wetlands. In- and outlet concentrations of nitrogen and other nutrients were measured every two weeks since December 2005. Collected water from pipe drains contained on average 30 mg N L -1. The mean N removal was 58% in SF (1655 kg N ha-1 year-1), 25% in SSF-reed (1447 kg ha-1 year-1) and 63% in SSF-straw (3622 kg N ha-1 year-1). SF and SSF-straw are functioning well. In SSF-reed, the amount of carbon seems to be insufficient to sustain nitrogen reduction. Disadvantage of SSF-straw is the negative removal rate of phosphorus (mean 16 kg ha-1). With a removal rate of about 60% within the system, about 20% of the leached nitrogen from the vegetable fields could be removed: about two-third of the leached water is collected in drains and half of the nitrate-rich drain water is collected for purification. The cost effectiveness (expressed as € per kg N removed) ranged between € 52 and € 104 kg-1 N for SF, between € 29 and 58 kg -1 N for SSF-straw and between € 161 and € 322 kg -1 N for SSF-reed. Cost reduction is possible by combining with other functions as water storage and nature development.
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Excerpt Climate change, in combination with the expanding human population, presents a formidable food security challenge: how will we feed a world population that is expected to grow by an additional 2.4 billion people by 2050? Population growth and the dynamics of climate change will also exacerbate other issues, such as desertification, deforestation, erosion, degradation of water quality, and depletion of water resources, further complicating the challenge of food security. These factors, together with the fact that energy prices may increase in the future, which will increase the cost of agricultural inputs, such as fertilizer and fuel, make the future of food security a major concern. Additionally, it has been reported that climate change can increase potential erosion rates, which can lower agricultural productivity by 10% to 20% (or more in extreme cases). Climate change could contribute to higher temperatures and evapotranspiration and lower precipitation across some regions. This will add additional pressure to draw irrigation water from some already overexploited aquifers, where the rate of water recharge is lower than the withdrawal rates. These and other water issues exacerbated by climate change present a serious concern because, on average, irrigated system yields are frequently double those of nonirrigated systems. The…
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Phosphorus fractions and phosphate adsorption characteristics of the floodplain sediments in the lower reaches of the Han River in China were investigated in order to provide the environmental managers with essential data on the Han River ecosystem. The results showed that the total phosphorus (TP) contents ranged from 643.86 to 985mgkg−1; inorganic phosphorus (IP) was the major fraction of TP, and calcium–bound phosphorus (Ca–P) was the main fraction of IP. Immersion played an important role in bioavailable phosphorus (exch-P and Fe/Al–P) desorption. The phosphorus adsorption process was completed within about 16h. The desorption amount of phosphorus increased within 7h and then decreased after 7h. The contents of native adsorbed phosphorus (wNAP), zero equilibrium phosphorus concentration (cEPC), total maximal adsorption amount of phosphorus (TQmax) and partitioning coefficient value (Kp) were calculated by corresponding formulae. wNAP ranged from 5.96 to 8.48mgkg−1 and cEPC ranged from 0.15 to 0.24mgL−1. wNAP was positively related to the exch-P and Ca–P contents (wexch-p and wCa–P) and negatively related to the Fe/Al–P contents (wFe/Al–P). A more significant linear relationship between TQmax and Kp was observed. The floodplain sediments would release phosphorus into the overlying water. The Han River ecosystem should be restored in response to the development of the sustainable Han River ecosystem.
Chapter
The biological state-of-the-art purification of wastewaters has gained momentum in recent times. The microalgal capability to reduce N and P contaminants, as well as chemical oxygen demand (COD), is implemented in wastewater treatment processes. This green microalgal strategy to integrate wastewater treatment and to achieve better energy efficiency mainly depends on the purpose, scalability, nutrient uptake of algal species and economic feasibility. Therefore, the microalgal approach is sustainable as compared to conventional methods of wastewater treatments because it generates no toxic waste and can grow in limited resources to meet the soaring energy demand of the world. In this chapter, we discuss the successful trials on pretreatment methods employing microalgae to treat a variety of wastewaters based on a different selection criterion. Further, we focused on different microalgae cultivation systems with an emphasis on their benefits and drawbacks. Then, a brief evaluation of the microalgae biorefinery technologies was done to generate renewable energy and high-value chemicals. Lastly, the challenges faced in integrated microalgal wastewater treatment processes were outlined for wide-scale applications on bioenergy production.
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Ecotechnology - the use of natural ecosystems to solve environmental problems - should be a part of efforts to shrink the zone of hypoxia in the Gulf of Mexico.
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Nitrate contamination of drinking water may increase cancer risk, because nitrate is endogenously reduced to nitrite and subsequent nitrosation reactions give rise to N-nitroso compounds; these compounds are highly carcinogenic and can act systemically. We analyzed cancer incidence in a cohort of 21,977 Iowa women who were 55-69 years of age at baseline in 1986 and had used the same water supply more than 10 years (87% >20 years); 16,541 of these women were on a municipal supply, and the remainder used a private well. We assessed nitrate exposure from 1955 through 1988 using public databases for municipal water supplies in Iowa (quartile cutpoints: 0.36, 1.01, and 2.46 mg per liter nitrate-nitrogen). As no individual water consumption data were available, we assigned each woman an average level of exposure calculated on a community basis; no nitrate data were available for women using private wells. Cancer incidence (N = 3,150 cases) from 1986 through 1998 was determined by linkage to the Iowa Cancer Registry. For all cancers, there was no association with increasing nitrate in drinking water, nor were there clear and consistent associations for non-Hodgkin lymphoma; leukemia; melanoma; or cancers of the colon, breast, lung, pancreas, or kidney. There were positive associations for bladder cancer [relative risks (RRs) across nitrate quartiles = 1, 1.69, 1.10, and 2.83] and ovarian cancer (RR = 1, 1.52, 1.81, and 1.84), and inverse associations for uterine cancer (RR = 1, 0.86, 0.86, and 0.55) and rectal cancer (RR = 1, 0.72, 0.95, and 0.47) after adjustment for a variety of cancer risk/protective factors, agents that affect nitrosation (smoking, vitamin C, and vitamin E intake), dietary nitrate, and water source. Similar results were obtained when analyses were restricted to nitrate level in drinking water from 1955 through 1964. The positive association for bladder cancer is consistent with some previous data; the associations for ovarian, uterine, and rectal cancer were unexpected.
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