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University of Nebraska - Lincoln

2017

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Articles 1 - 24 of 24

Full-Text Articles in Environmental Health and Protection

A Framework For Linking Population Model Development With Ecological Risk Assessment Objectives, Sandy Raimondo, Matthew Etterson, Nathan Pollesch, Kristina Garber, Andrew Kanarek, Wade Lehmann, Jill Awkerman Dec 2017

A Framework For Linking Population Model Development With Ecological Risk Assessment Objectives, Sandy Raimondo, Matthew Etterson, Nathan Pollesch, Kristina Garber, Andrew Kanarek, Wade Lehmann, Jill Awkerman

United States Environmental Protection Agency: Staff Publications

The value of models that link organism-level impacts to the responses of a population in ecological risk assessments (ERAs) has been demonstrated extensively over the past few decades. There is little debate about the utility of these models to translate multiple organism-level endpoints into a holistic interpretation of effect to the population; however, there continues to be a struggle for actual application of these models as a common practice in ERA. Although general frameworks for developing models for ERA have been proposed, there is limited guidance on when models should be used, in what form, and how to interpret model …


Factors Associated With Bat Mortality At Wind Energy Facilities In The United States, Maureen Thompson, Julie A. Beston, Matthew Etterson, Jay E. Diffendorfer, Scott R. Loss Sep 2017

Factors Associated With Bat Mortality At Wind Energy Facilities In The United States, Maureen Thompson, Julie A. Beston, Matthew Etterson, Jay E. Diffendorfer, Scott R. Loss

United States Environmental Protection Agency: Staff Publications

Hundreds of thousands of bats are killed annually by colliding with wind turbines in the U.S., yet little is known about factors causing variation in mortality across wind energy facilities. We conducted a quantitative synthesis of bat collision mortality with wind turbines by reviewing 218 North American studies representing 100 wind energy facilities. This data set, the largest compiled for bats to date, provides further evidence that collision mortality is greatest for migratory tree-roosting species (Hoary Bat [Lasiurus cinereus], Eastern Red Bat [Lasiurus borealis], Silver-haired Bat [Lasionycteris noctivagans]) and from July to October. Based …


Physical Water Scarcity Metrics For Monitoring Progress Towards Sdg Target 6.4: An Evaluation Of Indicator 6.4.2 “Level Of Water Stress”, D. Vanhama, A. Y. Hoekstra, Y. Wada, F. Bouraoui, A. De Roo, Mesfin Mekonnen, W. J. Van De Bund, O. Batelaan, P. Pavelic, W. G.M. Bastiaanssen, M. Kummu, J. Rockström, J. Liu, B. Bisselink, P. Ronco, A. Pistocchi, G. Bidoglio Sep 2017

Physical Water Scarcity Metrics For Monitoring Progress Towards Sdg Target 6.4: An Evaluation Of Indicator 6.4.2 “Level Of Water Stress”, D. Vanhama, A. Y. Hoekstra, Y. Wada, F. Bouraoui, A. De Roo, Mesfin Mekonnen, W. J. Van De Bund, O. Batelaan, P. Pavelic, W. G.M. Bastiaanssen, M. Kummu, J. Rockström, J. Liu, B. Bisselink, P. Ronco, A. Pistocchi, G. Bidoglio

Daugherty Water for Food Global Institute: Faculty Publications

Target 6.4 of the recently adopted Sustainable Development Goals (SDGs) dealswith the reduction ofwater scarcity. To monitor progress towards this target, two indicators are used: Indicator 6.4.1 measuring water use efficiency and 6.4.2 measuring the level of water stress (WS). This paper aims to identify whether the currently proposed indicator 6.4.2 considers the different elements that need to be accounted for in a WS indicator.WS indicators compare water use with water availability.We identify seven essential elements: 1) both gross and net water abstraction (or withdrawal) provide important information to understand WS; 2) WS indicators need to incorporate environmental flow requirements …


Water Use In Irrigated Agriculture: An Approach To Water Productivity In Drip And Sprinkler Systems, Fernanda Lamede Ferreira De Jesus, Jéssica Garcia Nascimento, Rubens Duarte Coelho, Sergio Nascimento Duarte, Fernando Campos Mendonça Aug 2017

Water Use In Irrigated Agriculture: An Approach To Water Productivity In Drip And Sprinkler Systems, Fernanda Lamede Ferreira De Jesus, Jéssica Garcia Nascimento, Rubens Duarte Coelho, Sergio Nascimento Duarte, Fernando Campos Mendonça

Daugherty Water for Food Global Institute: Faculty Publications

Irrigation plays an important role in agriculture and the increase in the irrigated area and scarce water resources have encouraged the use of irrigation systems and management systems that increase the efficiency of water use. Thus, maximize water productivity has been one of the most important challenges in agriculture. The present study aimed to relate information on water productivity for two irrigation systems, drip and sprinkler systems, with the purpose of understanding the characteristics of these systems and contributing to the advancement of studies and research carried out in the area. Technological innovations aimed at reducing consumption and increasing water …


Model Application Niche Analysis: Assessing The Transferability And Generalizability Of Ecological Models, Jessica B. Moon, Theodore H. Dewitt, Melissa N. Errend, Randall J. F. Bruins, Mary E. Kentula, Sarah J. Chamberlain, M. Siobhan Fennessy, Kusum J. Naithani Aug 2017

Model Application Niche Analysis: Assessing The Transferability And Generalizability Of Ecological Models, Jessica B. Moon, Theodore H. Dewitt, Melissa N. Errend, Randall J. F. Bruins, Mary E. Kentula, Sarah J. Chamberlain, M. Siobhan Fennessy, Kusum J. Naithani

United States Environmental Protection Agency: Staff Publications

The use of models by ecologists and environmental managers, to inform environmental management and decision-making, has grown exponentially in the past 50 yr. Due to logistical, economical, and theoretical benefits, model users frequently transfer preexisting models to new sites where data are scarce. Modelers have made significant progress in understanding how to improve model generalizability during model development. However, models are always imperfect representations of systems and are constrained by the contextual frameworks used during their development. Thus, model users need better ways to evaluate the possibility of unintentional misapplication when transferring models to new sites. We propose a method …


Loss Of Buffer Value Due To Aquifer Depletion: The Case Of High Plains Aquifer, Mani Rouhi Rad, Timothy Foster, Nicholas Brozovic Aug 2017

Loss Of Buffer Value Due To Aquifer Depletion: The Case Of High Plains Aquifer, Mani Rouhi Rad, Timothy Foster, Nicholas Brozovic

Daugherty Water for Food Global Institute: Faculty Publications

Existing literature in economics and engineering do not realistically capture the effects of aquifer depletion on loss of profits from agricultural production. While the former literature ignores the physical characteristics of aquifer and the relationship between aquifer levels and groundwater availability, the latter strand of literature does not consider farmers' decisionmaking as a result of aquifer depletion. Misspecification of these relationships and their effect on irrigation decisions can result in misunderstanding the consequences of aquifer depletion and may provide ineffective policies. This paper provides a framework to study the effects of aquifer depletion on the profit of agricultural production. We …


Nuclear Weapons In A Changing Climate: Probability, Increasing Risks, And Perception, Adam Liska, Tyler R. White, Eric Holley, Robert J. Oglesby Jul 2017

Nuclear Weapons In A Changing Climate: Probability, Increasing Risks, And Perception, Adam Liska, Tyler R. White, Eric Holley, Robert J. Oglesby

Adam Liska Papers

Many people tend to think that the outcome of any nuclear weapons use today will result in an escalatory situation with apocalyptic outcomes for the countries involved. Yet many factors are increasing the probability of the limited use of nuclear weapons (e.g., 1 to 20 warheads) in a range of conflict scenarios. Previous atmospheric model simulations of regional nuclear conflicts employing many relatively small bombs have been estimated to cause a global “nuclear autumn,” with great reductions in agricultural productivity, stratospheric ozone loss, and spread of hazardous radioactive fallout. The totality of these effects would result in widespread damage …


Evaluating The Impacts Of Farmers’ Behaviors On A Hypothetical Agricultural Water Market Based On Double Auction, Erhu Du, Ximing Cai, Barbara Minsker May 2017

Evaluating The Impacts Of Farmers’ Behaviors On A Hypothetical Agricultural Water Market Based On Double Auction, Erhu Du, Ximing Cai, Barbara Minsker

Daugherty Water for Food Global Institute: Faculty Publications

Agricultural water markets are considered effective instruments to mitigate the impacts of water scarcity and to increase crop production. However, previous studies have limited understanding of how farmers’ behaviors affect the performance of water markets. This study develops an agent-based model to explicitly incorporate farmers’ behaviors, namely irrigation behavior (represented by farmers’ sensitivity to soil water deficit k) and bidding behavior (represented by farmers’ rent seeking l and learning rate b), in a hypothetical water market based on a double auction. The model is applied to the Guadalupe River Basin in Texas to simulate a hypothetical agricultural water market under …


Mechanistic Modeling Of Insecticide Risks To Breeding Birds In North American Agroecosystems, Matthew Etterson, Kristina Garber, Edward Odenkirchen May 2017

Mechanistic Modeling Of Insecticide Risks To Breeding Birds In North American Agroecosystems, Matthew Etterson, Kristina Garber, Edward Odenkirchen

United States Environmental Protection Agency: Staff Publications

Insecticide usage in the United States is ubiquitous in urban, suburban, and rural environments. There is accumulating evidence that insecticides adversely affect non-target wildlife species, including birds, causing mortality, reproductive impairment, and indirect effects through loss of prey base, and the type and magnitude of such effects differs by chemical class, or mode of action. In evaluating data for an insecticide registration application and for registration review, scientists at the United States Environmental Protection Agency (USEPA) assess the fate of the insecticide and the risk the insecticide poses to the environment and non-target wildlife. Current USEPA risk assessments for pesticides …


Funding Strategies For Non-Traditional University Ms4 Stormwater Programs, Elizabeth M. Garrett May 2017

Funding Strategies For Non-Traditional University Ms4 Stormwater Programs, Elizabeth M. Garrett

Community and Regional Planning Program: Theses and Student Projects

Stormwater programs have historically been stymied by lack of proper funding resources. Unlike drinking water and sanitary sewer utility services that long ago transitioned to enterprise funds, a stormwater utility continues to evade stable and direct revenue sources throughout much of the United States. Inefficiently funded stormwater programs utilizing general funding practices leaves stormwater management programs unable to properly plan for long-term improvement, management, regulatory compliance, and maintenance. Funding research has established that forms of direct funding sources are crucial for successful stormwater programs, however, focus has been directed to strategies for municipalities. This paper will attempt to analyze, through …


Influence Of Internal Variability On Population Exposure To Hydroclimatic Changes, Justin S. Mankin, Daniel Viviroli, Mesfin Mekonnen, Arjen Y. Hoekstra, Radley M. Horton, Jason E. Smerdon, Noah S. Diffenbaugh Mar 2017

Influence Of Internal Variability On Population Exposure To Hydroclimatic Changes, Justin S. Mankin, Daniel Viviroli, Mesfin Mekonnen, Arjen Y. Hoekstra, Radley M. Horton, Jason E. Smerdon, Noah S. Diffenbaugh

Daugherty Water for Food Global Institute: Faculty Publications

Future freshwater supply, human water demand, and people’s exposure to water stress are subject to multiple sources of uncertainty, including unknown future pathways of fossil fuel and water consumption, and ‘irreducible’ uncertainty arising from internal climate system variability. Such internal variability can conceal forced hydroclimatic changes on multi-decadal timescales and near-continental spatial-scales. Using three projections of population growth, a large ensemble from a single Earth system model, and assuming stationary per capita water consumption, we quantify the likelihoods of future population exposure to increased hydroclimatic deficits, which we define as the average duration and magnitude by which evapotranspiration exceeds precipitation …


Factors That Influence Vital Rates Of Seaside And Saltmarsh Sparrows In Coastal New Jersey, Usa, Samuel G. Roberts, Rebecca A. Longenecker, Matthew A. Etterson, Katharine J. Ruskin, Chris S. Elphick, Brian J. Olsen, W. Gregory Shriver Mar 2017

Factors That Influence Vital Rates Of Seaside And Saltmarsh Sparrows In Coastal New Jersey, Usa, Samuel G. Roberts, Rebecca A. Longenecker, Matthew A. Etterson, Katharine J. Ruskin, Chris S. Elphick, Brian J. Olsen, W. Gregory Shriver

United States Environmental Protection Agency: Staff Publications

As saltmarsh habitat continues to disappear, understanding the factors that influence the population dynamics of saltmarsh breeding birds is an important step in the conservation of these declining species. Using 5 yrs (2011–2015) of demographic data, we evaluated and compared apparent adult survival and nest survival of Seaside (Ammodramus maritimus) and Saltmarsh (A. caudacutus) sparrows at the Edwin B. Forsythe National Wildlife Refuge in New Jersey, USA. We determined the effect of site management history (unditched vs. ditched marshes) on adult and nest survival to aid in prioritizing future management or restoration actions. Apparent adult …


Effects Of Initial Aquifer Conditions On Economic Benefits From Groundwater Conservation, T. Foster, N. Brozovic, A. P. Butler Jan 2017

Effects Of Initial Aquifer Conditions On Economic Benefits From Groundwater Conservation, T. Foster, N. Brozovic, A. P. Butler

Daugherty Water for Food Global Institute: Faculty Publications

Worldwide, there is growing recognition of the need to reduce agricultural groundwater use in response to rapid rates of aquifer depletion. To date, however, few studies have evaluated how benefits of conservation vary along an aquifer’s depletion pathway. To address this question, we develop an integrated modeling framework that couples an agro-economic model of farmers’ field-level irrigation decisionmaking with a borehole-scale groundwater flow model. Unique to this framework is the explicit consideration of the dynamic reductions in well yields that occur as an aquifer is depleted, and how these changes in intraseasonal groundwater supply affect farmers’ ability to manage production …


Statistical Survey Of Persistent Organic Pollutants: Risk Estimations To Humans And Wildlife Through Consumption Of Fish From U.S. Rivers, Angela L. Batt, John B. Wathen, James M. Lazorchak, Anthony R. Olsen, Thomas M. Kincaid Jan 2017

Statistical Survey Of Persistent Organic Pollutants: Risk Estimations To Humans And Wildlife Through Consumption Of Fish From U.S. Rivers, Angela L. Batt, John B. Wathen, James M. Lazorchak, Anthony R. Olsen, Thomas M. Kincaid

United States Environmental Protection Agency: Staff Publications

U.S. EPA conducted a national statistical survey of fish tissue contamination at 540 river sites (representing 82 954 river km) in 2008−2009, and analyzed samples for 50 persistent organic pollutants (POPs), including 21 PCB congeners, 8 PBDE congeners, and 21 organochlorine pesticides. The survey results were used to provide national estimates of contamination for these POPs. PCBs were the most abundant, being measured in 93.5% of samples. Summed concentrations of the 21 PCB congeners had a national weighted mean of 32.7 μg/kg and a maximum concentration of 857 μg/kg, and exceeded the human health cancer screening value of 12 μg/kg …


A Photosynthesis-Based Two-Leaf Canopy Stomatal Conductance Model For Meteorology And Air Quality Modeling With Wrf/Cmaq Px Lsm, Limei Ran, Jonathan Pleim, Conghe Song, Larry Band, John T. Walker, Francis S. Binkowski Jan 2017

A Photosynthesis-Based Two-Leaf Canopy Stomatal Conductance Model For Meteorology And Air Quality Modeling With Wrf/Cmaq Px Lsm, Limei Ran, Jonathan Pleim, Conghe Song, Larry Band, John T. Walker, Francis S. Binkowski

United States Environmental Protection Agency: Staff Publications

A coupled photosynthesis-stomatal conductance model with single-layer sunlit and shaded leaf canopy scaling is implemented and evaluated in a diagnostic box model with the Pleim-Xiu land surface model (PX LSM) and ozone deposition model components taken directly from the meteorology and air quality modeling system—WRF/CMAQ (Weather Research and Forecast model and Community Multiscale Air Quality model). The photosynthesis-based model for PX LSM (PX PSN) is evaluated at a FLUXNET site for implementation against different parameterizations and the current PX LSM approach with a simple Jarvis function (PX Jarvis). Latent heat flux (LH) from PX PSN is further evaluated at five …


Atp Binding Cassette Sub-Family Member 2 (Abcg2) And Xenobiotic Exposure During Early Mouse Embryonic Stem Cell Differentiation, Mitchell B. Rosen, Susan C. Jeffay, Harriette P. Nichols, Maria R. Hoopes, E. Sidney Hunter Iii Jan 2017

Atp Binding Cassette Sub-Family Member 2 (Abcg2) And Xenobiotic Exposure During Early Mouse Embryonic Stem Cell Differentiation, Mitchell B. Rosen, Susan C. Jeffay, Harriette P. Nichols, Maria R. Hoopes, E. Sidney Hunter Iii

United States Environmental Protection Agency: Staff Publications

Background: ATP binding cassette sub-family member 2 (ABCG2) is a welldefined efflux transporter found in a variety of tissues. The role of ABCG2 during early embryonic development, however, is not established. Previous work which compared data from the ToxCast screening program with that from in-house studies suggested an association exists between exposure to xenobiotics that regulate Abcg2 transcription and differentiation of mouse embryonic stem cells (mESC), a relationship potentially related to redox homeostasis.

Methods: mESC were grown for up to 9 days. Pharmacological inhibitors were used to assess transporter function with and without xenobiotic exposure. Proliferation and differentiation were …


Aquacrop-Os: An Open Source Version Of Fao’S Crop Water Productivity Model, T. Foster, N. Brozovic, A. P. Butler, C. M. U. Neale, D. Raes, P. Steduto, E. Fereres, T. C. Hsiao Jan 2017

Aquacrop-Os: An Open Source Version Of Fao’S Crop Water Productivity Model, T. Foster, N. Brozovic, A. P. Butler, C. M. U. Neale, D. Raes, P. Steduto, E. Fereres, T. C. Hsiao

Daugherty Water for Food Global Institute: Faculty Publications

Crop simulation models are valuable tools for quantifying crop yield response to water, and for devising strategies to improve agricultural water management. However, applicability of the majority of crop models is limited greatly by a failure to provide open-access to model source code. In this study, we present an open-source version of the FAO AquaCrop model, which simulates efficiently water-limited crop production across diverse environmental and agronomic conditions. Our model, called AquaCrop-OpenSource (AquaCrop-OS), can be run in multiple programming languages and operating systems. Support for parallel execution reduces significantly simulation times when applying the model in large geospatial frameworks, for …


In-Situ Observation And Transport Modelling Of Arsenic In Gangetic Plain, India, Pankaj Kumar Gupta, Pranjay Joshi, Jahangeer Jan 2017

In-Situ Observation And Transport Modelling Of Arsenic In Gangetic Plain, India, Pankaj Kumar Gupta, Pranjay Joshi, Jahangeer

Daugherty Water for Food Global Institute: Faculty Publications

The focus of this study is to investigate the arsenic movement and impacts on the residual concentrations on groundwater pollution load. The Gangetic plain area in the Ballia, Uttar Pradesh is selected as study area, which is also reported to extreme arsenic pollution in soil-water system. A modelling approach is developed to assess the arsenic flux in partially saturated zone using data of soil texture, soil hydraulic properties and stratigraphy. Soil type, slope, and land-use cover is considered for estimating the transient flux at the top boundary from daily precipitation and evapotranspiration data of the study area. Solute transport in …


Paid To Pump: How A Tax Credit Could Discourage Conservation Of The High Plains Aquifer, S. Polzkill,, A. Stejskal, H. Wilke, Anna Wistrom, Katherine E. B. Gibson, Mindy J. Spiehs, Nicholas Brozovic Jan 2017

Paid To Pump: How A Tax Credit Could Discourage Conservation Of The High Plains Aquifer, S. Polzkill,, A. Stejskal, H. Wilke, Anna Wistrom, Katherine E. B. Gibson, Mindy J. Spiehs, Nicholas Brozovic

Daugherty Water for Food Global Institute: Faculty Publications

In 1965’s United States v. Shurbet case, an irrigator from Texas asserted his claim for a depletion tax deduction for groundwater pumped from the High Plains Aquifer. He argued that the unique conditions of the southern High Plains region - a plateau where the shallow aquifer is recharged only through precipitation at a slow rate - meant the groundwater resource would be depleted in time. The state argued that groundwater was not fundamentally an exhaustible natural deposit, but the Supreme Court concluded the tax deduction was appropriate given the “peculiar” conditions in the area. It was stated the decision was …


Pathways To Increasing Farmer-Led Investments In Sustainable Agricultural Water Management In Sub-Saharan Africa, Douglas J. Merrey, Peter G. Mccornick, Molly C. Nance Jan 2017

Pathways To Increasing Farmer-Led Investments In Sustainable Agricultural Water Management In Sub-Saharan Africa, Douglas J. Merrey, Peter G. Mccornick, Molly C. Nance

Daugherty Water for Food Global Institute: Faculty Publications

Without a transformative leap forward in the use of irrigation, Africa will continue falling short in the struggle to feed its growing population, improve its people’s nutrition, grow its economies, adapt to the impacts of climate change, and eliminate poverty. While Africans must lead this transformation for it to be successful, the international community can help African countries substantially increase the use of more productive and sustainable water management practices and unlock the potential of farmer-led irrigated agriculture. Achieving highly productive irrigated agricultural systems in Africa requires an enabling environment that facilitates the full engagement of farmers, public and private …


Weight Of Evidence Evaluation Of A Network Of Adverse Outcome Pathways Linking Activation Of The Nicotinic Acetylcholine Receptor In Honey Bees To Colony Death, Carlie A. Lalone, Daniel L. Villeneuve, Judy Wu-Smart, Rebecca Y. Milsk, Keith Sappington, Kristina V. Garber, Justin Housenger, Gerald T. Ankley Jan 2017

Weight Of Evidence Evaluation Of A Network Of Adverse Outcome Pathways Linking Activation Of The Nicotinic Acetylcholine Receptor In Honey Bees To Colony Death, Carlie A. Lalone, Daniel L. Villeneuve, Judy Wu-Smart, Rebecca Y. Milsk, Keith Sappington, Kristina V. Garber, Justin Housenger, Gerald T. Ankley

United States Environmental Protection Agency: Staff Publications

Ongoing honey bee (Apis mellifera) colony losses are of significant international concern because of the essential role these insects play in pollinating crops. Both chemical and non-chemical stressors have been implicated as possible contributors to colony failure; however, the potential role(s) of commonly-used neonicotinoid insecticides has emerged as particularly concerning. Neonicotinoids act on the nicotinic acetylcholine receptors (nAChRs) in the central nervous system to eliminate pest insects. However, mounting evidence indicates that neonicotinoids also may adversely affect beneficial pollinators, such as the honey bee, via impairments on learning and memory, and ultimately foraging success. The specificmechanisms linking activation …


Nebraska Public Water Supply Program Summary Report 2017 Jan 2017

Nebraska Public Water Supply Program Summary Report 2017

Nebraska Department of Environmental Quality: Reports

The United States Environmental Protection Agency (EPA) established the Public Water System Supervision (PWSS) Program under the authority of the 1974 Safe Drinking Water Act (SDWA). Under the SDWA and the 1986 Amendments, EPA sets national limits on contaminant levels in drinking water to ensure that the water is safe for human consumption. These limits are known as Maximum Contaminant Levels (MCLs) and Maximum Residual Disinfectant Levels (MRDLs). For some regulations, EPA establishes treatment techniques in lieu of an MCL to control unacceptable levels of contaminants in water.


2017 Nebraska Water Monitoring Programs Report, Marty Link, Ryan Chapman Jan 2017

2017 Nebraska Water Monitoring Programs Report, Marty Link, Ryan Chapman

Nebraska Department of Environmental Quality: Reports

The Nebraska Department of Environmental Quality (NDEQ) is charged with monitoring, assessing, and to the extent possible, managing the state’s water resources. The purpose of this work is to protect and maintain high quality water and encourage or execute activities to improve poor water quality. Monitoring is done on nearly 17,000 miles of flowing rivers and streams, more than 134,000 acres of surface water in lakes and reservoirs, as well as the vast storage of groundwater in Nebraska’s aquifers.


2017 Nebraska Groundwater Quality Monitoring Report Jan 2017

2017 Nebraska Groundwater Quality Monitoring Report

Nebraska Department of Environmental Quality: Reports

The 2001 Nebraska Legislature passed LB329 (Neb. Rev. Stat. §46-1304) which, in part, directed the Nebraska Department of Environmental Quality (NDEQ) to report on groundwater quality monitoring in Nebraska. Reports have been issued annually since December 2001. The text of the statute applicable to this report follows: “The Department of Environmental Quality shall prepare a report outlining the extent of ground water quality monitoring conducted by natural resources districts during the preceding calendar year. The department shall analyze the data collected for the purpose of determining whether or not ground water quality is degrading or improving and shall present the …