scholarly journals Multicompartment Ecosystem Mass Balances as a Tool for Understanding and Managing the Biogeochemical Cycles of Human Ecosystems

2001 ◽  
Vol 1 ◽  
pp. 802-808 ◽  
Author(s):  
Lawrence A. Baker ◽  
Diane Hope ◽  
Ying Xu ◽  
Jennifer Edmonds
Keyword(s):  
Management Practices ◽  
Management Strategies ◽  
The United States ◽  
N Balance ◽  
N Leaching ◽  
Treatment Technology ◽  
Ecosystem Level ◽  
Human Ecosystems ◽  
N Management ◽  
Central Arizona

Nitrogen remains a ubiquitous pollutant in surface and groundwater throughout the United States, despite 30 years of pollution control efforts. A detailed multicompartment N balance for the Central Arizona-Phoenix ecosystem is used to illustrate how an ecosystem-level approach can be used to develop improved N management strategies. The N balance is used to demonstrate how nitrate in pumped groundwater used for crop irrigation could be used to reduce inputs of commercial fertilizer and decrease N leaching to aquifers. Effectively managing N pollution also will require an understanding of the complex factors that control the N balance, including targeted regulations, individual human behavior, land-use conversion, and other ecosystem management practices that affect the N balance. These sometimes countervailing factors are illustrated with several scenarios of wastewater treatment technology and population growth in the Phoenix area. Management of N eventually must be coupled to management of other elements, notably carbon, phosphorus, and salts. We postulate that an ecosystem framework for pollution management will result in strategies that are more effective, fairer, and less expensive than current approaches.

Concepts and Practices for Improving Nitrogen Management for Vegetables

1992 ◽  
Vol 2 (1) ◽  
pp. 121-125 ◽  
Author(s):  
George J. Hochmuth
Keyword(s):  
Water Management ◽  
Management Practices ◽  
Management Strategies ◽  
N Fertilization ◽  
Nitrogen Management ◽  
Land Grant ◽  
Land Grant Universities ◽  
Production Practices ◽  
Negative Impacts ◽  
N Management

Efficient N management practices usually involve many potential strategies, but always involve choosing the correct amount of N and the coupling of N management to efficient water management. Nitrogen management strategies are integral parts of improved production practices recommended by land-grant universities such as the Institute of Food and Agricultural Sciences, Univ. of Florida. This paper, which draws heavily on research and experience in Florida, outlines the concepts and technologies for managing vegetable N fertilization to minimize negative impacts on the environment.

A steady-state N balance approach for sustainable smallholder farming

2021 ◽  
Vol 118 (39) ◽  
pp. e2106576118
Author(s):  
Yulong Yin ◽  
Rongfang Zhao ◽  
Yi Yang ◽  
Qingfeng Meng ◽  
Hao Ying ◽  
...  
Keyword(s):  
Steady State ◽  
Management Practices ◽  
Global Climate ◽  
N Balance ◽  
Smallholder Farming ◽  
N Losses ◽  
Application Range ◽  
High Yields ◽  
N Management ◽  
On Farm

Hundreds of millions of smallholders in emerging countries substantially overuse nitrogen (N) fertilizers, driving local environmental pollution and global climate change. Despite local demonstration-scale successes, widespread mobilization of smallholders to adopt precise N management practices remains a challenge, largely due to associated high costs and complicated sampling and calculations. Here, we propose a long-term steady-state N balance (SSNB) approach without these complications that is suitable for sustainable smallholder farming. The hypothesis underpinning the concept of SSNB is that an intensively cultivated soil–crop system with excessive N inputs and high N losses can be transformed into a steady-state system with minimal losses while maintaining high yields. Based on SSNB, we estimate the optimized N application range across 3,824 crop counties for the three staple crops in China. We evaluated SSNB first in ca. 18,000 researcher-managed on-farm trials followed by testing in on-farm trials with 13,760 smallholders who applied SSNB-optimized N rates under the guidance of local extension staff. Results showed that SSNB could significantly reduce N fertilizer use by 21 to 28% while maintaining or increasing yields by 6 to 7%, compared to current smallholder practices. The SSNB approach could become an effective tool contributing to the global N sustainability of smallholder agriculture.

scholarly journals Limitations of Improved Nitrogen Management to Reduce Nitrate Leaching and Increase Use Efficiency

2001 ◽  
Vol 1 ◽  
pp. 10-16 ◽  
Author(s):  
James L. Baker
Keyword(s):  
Water Quality ◽  
Nitrate Leaching ◽  
Management Practices ◽  
Nitrate Nitrogen ◽  
Nitrogen Management ◽  
N Leaching ◽  
N Loss ◽  
Use Efficiency ◽  
Rate Method ◽  
N Management

The primary mode of nitrogen (N) loss from tile-drained row-cropped land is generally nitrate-nitrogen (NO3-N) leaching. Although cropping, tillage, and N management practices can be altered to reduce the amount of leaching, there are limits as to how much can be done. Data are given to illustrate the potential reductions for individual practices such as rate, method, and timing of N applications. However, most effects are multiplicative and not additive; thus it is probably not realistic to hope to get overall reductions greater than 25 to 30% with in-field practices alone. If this level of reduction is insufficient to meet water quality goals, additional off-site landscape modifications may be necessary.

scholarly journals Evaluation of drill seeding patterns and nitrogen management strategies for wet and dry land rice

2013 ◽  
Vol 37 (4) ◽  
pp. 559-571 ◽  
Author(s):  
M Akkas Ali ◽  
JK Ladha ◽  
J Rickman ◽  
JS Lales ◽  
M Murshedul Alam
Keyword(s):  
Grain Yield ◽  
Management Strategies ◽  
Crop Productivity ◽  
Direct Seeding ◽  
N Balance ◽  
Dry Land ◽  
Available N ◽  
Land Preparation ◽  
N Management ◽  
N Use

Many Asian farmers are shifting from rice transplanting to direct seeding because the latter requires less labour, time, drudgery, and cultivation cost. Direct seeding is usually practiced in either wet or dry land preparation depending on water availability. The present study aimed at evaluating the potential of single and paired rows drill seeding patterns and five N management strategies on crop productivity, N use-efficiency, and apparent N balance. The experiment was laid out in a split plot design with two seeding patterns as main plots and five N treatments as subplots with three replications. Drill seeding did not affect grain yield, water, and N use-efficiencies and N balance. Grain yield increased with LCC-based N management with the lower N fertilizer input. Soil available N after 2 years of rice cropping was similar to the amount at the beginning indicating most of applied fertilizer N was lost. DOI: http://dx.doi.org/10.3329/bjar.v37i4.14374 Bangladesh J. Agril. Res. 37(4): 559-571, December 2012

scholarly journals Identifying Sustainable Nitrogen Management Practices for Tea Plantations

Nitrogen ◽  
2022 ◽  
Vol 3 (1) ◽  
pp. 43-57
Author(s):  
Rhys Rebello ◽  
Paul J. Burgess ◽  
Nicholas T. Girkin
Keyword(s):  
Management Practices ◽  
Synergistic Effects ◽  
Soil Health ◽  
N Leaching ◽  
N2o Emissions ◽  
Nitrification Inhibitors ◽  
Financial Barriers ◽  
Trade Offs ◽  
High Yields ◽  
N Management

Tea (Camellia sinensis L.) is the most widely consumed beverage in the world. It is mostly grown in the tropics with a heavy dependence on mineral nitrogen (N) fertilisers to maintain high yields while minimising the areas under cultivation. However, N is often applied in excess of crop requirements, resulting in substantial adverse environmental impacts. We conducted a systematic literature review, synthesising the findings from 48 studies to assess the impacts of excessive N application on soil health, and identify sustainable, alternative forms of N management. High N applications lead to soil acidification, N leaching to surface and groundwater, and the emission of greenhouse gases including nitrous oxide (N2O). We identified a range of alternative N management practices, the use of organic fertilisers, a mixture of organic and inorganic fertilisers, controlled release fertilisers, nitrification inhibitors and soil amendments including biochar. While many practices result in reduced N loading or mitigate some adverse impacts, major trade-offs include lower yields, and in some instances increased N2O emissions. Practices are also frequently trialled in isolation, meaning there may be a missed opportunity from assessing synergistic effects. Moreover, adoption rates of alternatives are low due to a lack of knowledge amongst farmers, and/or financial barriers. The use of site-specific management practices which incorporate local factors (for example climate, tea variety, irrigation requirements, site slope, and fertiliser type) are therefore recommended to improve sustainable N management practices in the long term.

scholarly journals 2nd International Arctic Ungulate Conference

Rangifer ◽  
1996 ◽  
Vol 16 (2) ◽  
pp. 49
Author(s):  
A. Anonymous
Keyword(s):  
Population Dynamics ◽  
Behavior Genetics ◽  
Management Strategies ◽  
The United States ◽  
Research Unit ◽  
Federal Agencies ◽  
Lessons Learned ◽  
Ecosystem Level ◽  
Commercial Organizations ◽  
The University

The 2nd International Arctic Ungulate Conference was held 13-17 August 1995 on the University of Alaska Fairbanks campus. The Institute of Arctic Biology and the Alaska Cooperative Fish and Wildlife Research Unit were responsible for organizing the conference with assistance from biologists with state and federal agencies and commercial organizations. David R. Klein was chair of the conference organizing committee. Over 200 people attended the conference, coming from 10 different countries. The United States, Canada, and Norway had the largest representation. The conference included invited lectures; panel discussions, and about 125 contributed papers. There were five technical sessions on Physiology and Body Condition; Habitat Relationships; Population Dynamics and Management; Behavior, Genetics and Evolution; and Reindeer and Muskox Husbandry. Three panel sessions discussed Comparative caribou management strategies; Management of introduced, reestablished, and expanding muskox populations; and Health risks in translocation of arctic ungulates. Invited lectures focused on the physiology and population dynamics of arctic ungulates; contaminants in food chains of arctic ungulates and lessons learned from the Chernobyl accident; and ecosystem level relationships of the Porcupine Caribou Herd.

scholarly journals A Review of the Biology, Ecology, and Management of Plum Curculio (Coleoptera: Curculionidae)

2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Timothy P Lampasona ◽  
Cesar Rodriguez-Saona ◽  
Tracy C Leskey ◽  
Anne L Nielsen
Keyword(s):  
Management Practices ◽  
Management Strategies ◽  
The United States ◽  
Conotrachelus Nenuphar ◽  
Future Directions ◽  
Geographic Ranges ◽  
Plum Curculio ◽  
Fruit Abortion ◽  
Chemical Inputs ◽  
And Control

Abstract The plum curculio, Conotrachelus nenuphar Herbst (Coleoptera: Curculionidae), is an insect native to the Americas that is a serious pest of stone and pome fruits in the United States and Canada. Failure to effectively manage this insect may result in up to 85% damaged fruit at harvest, as well as early season fruit abortion. Conotrachelus nenuphar is oligophagous, feeding and ovipositing on many Rosaceous plants, including apple, peach, plum, cherry, quince, and pear. Additionally, C. nenuphar in limited geographic ranges utilizes alternate hosts such as highbush blueberry (Ericaceae) and Muscadine grape (Vitaceae). Despite its long history as a pest, integrated pest management (IPM) lags behind similarly damaging native fruit pests. Although significant progress has been made on the identification of attractive lures for monitoring C. nenuphar adults, development of behaviorally based management strategies, and biological control with entomopathogenic nematodes, growers continue to rely heavily on top-down chemical inputs to manage this pest. Most of the research to date comes from studies done in apples where alternative management practices for C. nenuphar have, to some extent, been adopted; however, less IPM-based information is available for other susceptible crops. In this review, we summarize the history, biology, ecology, behavior, and control of C. nenuphar and future directions for IPM research.

scholarly journals 453 N Management Strategies Affect Watermelon Yield and N Leaching

HortScience ◽  
1999 ◽  
Vol 34 (3) ◽  
pp. 522E-522
Author(s):  
G. Hochmuth ◽  
S. Locascio ◽  
R. Hochmuth ◽  
Jennifer Hornsby ◽  
D. Haman ◽  
...  
Keyword(s):  
Soil Solution ◽  
Drip Irrigation ◽  
Irrigation System ◽  
Management Strategies ◽  
Poultry Manure ◽  
N Leaching ◽  
Fertilization Program ◽  
Nitrate N ◽  
N Management ◽  
Polyethylene Mulch

Nitrate concentrations in the springs and rivers in northern Florida have been increasing, and several state agencies are interested in implementing nitrogen management programs on farms to reduce N entering the groundwater. Watermelon was grown in the first season of a six-season project under various cultural and fertilization programs to investigate the relationship of N management with N leaching. Treatments were a factorial arrangement of two cultural systems (polyethylene mulch with drip-irrigated beds and unmulched, overhead irrigated beds) and three N fertilization programs [N at the extension-recommended rate, N at the commercial-watermelon-producer rate (1.5 times recommended), or N at the recommended rate with 50% of N from poultry manure]. Nitrate in the soil beneath the watermelon crop was monitored at the 2-m depth with porous-crop suction lysimeters and soil sampling. Yields were greater with the mulch/drip irrigation system compared with the unmulched/sprinkler cultural system; however, fertilization program had no effect on yield. Nitrate-N concentrations in the soil solution at the 2-m depth with all fertilizer treatments were only slightly elevated (3 to 5 mg·L-1) above that in the unfertilized soil (< 1.0 mg·L-1) early in the season when no rain fell. Later in the season, soil solution nitrate-N concentrations at the 2-m depth increased to >50 mg·L -1 with the unmulched treatment and with the greater fertilization rate. Polyethylene mulch, drip irrigation, and recommended N rate combined to maintain groundwater nitrate-N concentration below 10 mg·L-1 for most of the production season and only slightly above 10 mg·L-1 during the summer off-season when rainfall was frequent.

Developing a new regulatory paradigm to address the impacts of diffuse pollution attributable to agriculture

1999 ◽  
Vol 39 (12) ◽  
pp. 299-305 ◽  
Author(s):  
Jan McNitt ◽  
Ron Kepford
Keyword(s):  
Land Management ◽  
Environmental Protection Agency ◽  
Management Practices ◽  
Management Strategies ◽  
Pollution Abatement ◽  
The United States ◽  
Time Frame ◽  
Point Sources ◽  
Diffuse Pollution ◽  
Watershed Approach

To control pollution attributable to livestock operations, the statutory and regulatory scheme of the US Clean Water Act focuses on implementing structural controls to contain animal waste. While the United States Environmental Protection Agency (USEPA) is empowered only to regulate point sources, existing authority may be extended to regulate diffuse runoff associated with certain livestock facilities. Current water pollution abatement programs, however, have not responded to the differences inherent in diffuse pollution and the land management strategies necessary to control and abate its impacts. The Planned Intervention Micro-watershed Approach (PIMA) recognizes this distinction, offering a method of refining land management strategies while keeping existing point source pollution regulation and enforcement mechanisms in place. Within a limited time frame, producers have flexibility to develop and implement cost-effective management practices that achieve environmental goals. Planned intervention is integrated with a micro-watershed approach to watershed management which uses small, hydrologically discrete areas to target diffuse pollution sources and direct intervention efforts. This approach utilizes local stakeholder input and participation to create a bottom-up, community-based institutional framework for addressing diffuse pollution from agricultural sources that satisfies water quality objectives.

scholarly journals Moyamoya disease in the midwestern United States

1998 ◽  
Vol 5 (5) ◽  
pp. E3 ◽  
Author(s):  
Nicholas M. Wetjen ◽  
P. Charles Garell ◽  
Nicholas V. Stence ◽  
Christopher M. Loftus
Keyword(s):  
United States ◽  
Moyamoya Disease ◽  
Management Practices ◽  
Correct Diagnosis ◽  
Management Strategies ◽  
Superficial Temporal Artery ◽  
Age Distribution ◽  
Temporal Artery ◽  
The United States ◽  
Epidemiological Characteristics

There have been few investigations of moyamoya disease in the United States and no systematic description of the management practices or outcome from this population. The authors reviewed their experience with this disease to gain a better understanding and improve the treatment of patients with moyamoya disease in the United States. Over a 25-year period 30 patients with moyamoya disease have been treated at the University of Iowa. The cases were divided into patients who had classic, probable, and akin moyamoya disease. Results indicated that there was a bimodal age distribution and a female predominance of cases. In estimating the referral pattern of our institution, the authors determined that there were greater numbers of epidemiological characteristics than previously anticipated. Patients were treated either surgically or nonsurgically, and different management strategies were utilized in each of the major groups: superficial temporal artery to middle cerebral artery anastomosis and encephalodurosynangiosis in the surgical group; or antiplatelet, anticoagulation, or nonpharmacological intervention in the nonsurgical group. The authors conclude that there is a higher prevalence and incidence of moyamoya disease in the United States than previously reported and that there are some clinical characteristics of this disease that differ from the cases reported in southeast Asia. These differences may be due to genetic or environmental factors but can also be partly explained by the lower index of suspicion for this disease and, thus, a delay in or complete absence of the correct diagnosis.

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