Long-Term (15 Years) Results of NPS Controls in an Agricultural Watershed upon a Receiving Lake's Water Quality

1993 ◽  
Vol 28 (3-5) ◽  
pp. 441-449 ◽  
Author(s):  
Paul J. Garrison ◽  
Timothy R. Asplund
Keyword(s):  
Water Quality ◽  
Structural Changes ◽  
Soil Phosphorus ◽  
Water Clarity ◽  
Management Control ◽  
Agricultural Watershed ◽  
Control Measures ◽  
Phosphorus Loading ◽  
Phosphorus Concentration ◽  
White Clay

Nonpoint source controls were installed in a 1215 ha agricultural watershed in northeastern Wisconsin in the late 1970. Changes were made in handling of animal wastes and cropping practices to reduce runoff of sediment and nutrients. Modelling results predicted a reduction in phosphorus runoff of 30 percent. The water quality of White Clay Lake has worsened since the installation of NPS controls. The lake's phosphorus concentration has increased from a mean of 29 µg L−1 in the late 1970s to 44 µg L−1 in recent years. Water clarity has declined from 2.7 to 2.1 m and the mean summer chlorophyll levels have increased from 9 to 13 µg L−1 with peak values exceeding 40 µg L−1. Increased phosphorus loading is not the result of elevated precipitation but instead the failure of the control measures to sufficiently reduce P loading. Most of the effort was placed on structural changes while most of the P loading comes from cropland runoff. Further, soil phosphorus concentrations have increased because of artificial fertilizers and manure spreading. The White Clay Lake experience is discouraging since the majority of the polluters in this watershed utilized some NPS control practices, including 76 percent of the farms which installed waste management control facilities.

Impacts of agriculture on aquatic systems: lessons learnt and new unknowns in Northern Ireland

2001 ◽  
Vol 52 (1) ◽  
pp. 151 ◽  
Author(s):  
S. I. Heaney ◽  
R. H. Foy ◽  
G. J. A. Kennedy ◽  
W. W. Crozier ◽  
W. C. K. O' Connor
Keyword(s):  
Water Quality ◽  
Northern Ireland ◽  
Soluble Reactive Phosphorus ◽  
Phosphorus Loading ◽  
Phosphorus Concentration ◽  
The European Union ◽  
Blue Green Algae ◽  
Lough Neagh ◽  
The Impact

Agriculture in Northern Ireland depends on grass-based production, but since 1980, expansion of output has been effectively constrained by production limits set by the European Union agricultural policy. Despite this, long-term monitoring over several decades has shown significant degradation of water quality in Lough Neagh, with persistent high biomass of blue-green algae. Similar long-term studies have revealed a marked decline in the freshwater survival of salmon in the nearby River Bush. These changes may be related and reflect the impact of farming on water quality and salmonid production. Regular sampling of the inflowing rivers to Lough Neagh has shown that continued increase in lake phosphorus concentration has been primarily due to an increase in the soluble reactive phosphorus loading from agricultural diffuse sources. Similar diffuse inputs of agriculturally derived nutrients to the River Bush, leading to increased plant growth together with the accumulation of fine sediment in salmon spawning redds, are considered to be important in the decline of freshwater survival of salmon from egg to smolt. The impact of farming practices on lakes and rivers is considered in relation to understanding of the complex and interacting factors that link land use to water quality.

scholarly journals Watershed Response to Legacy Phosphorus and Best Management Practices in an Impacted Agricultural Watershed in Florida, U.S.A.

Land ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 977
Author(s):  
Yogesh P. Khare ◽  
Rajendra Paudel ◽  
Ruscena Wiederholt ◽  
Anteneh Z. Abiy ◽  
Thomas Van Lent ◽  
...  
Keyword(s):  
Water Quality ◽  
Best Management Practices ◽  
Environmental Planning ◽  
Management Practices ◽  
Soil Phosphorus ◽  
Agricultural Watershed ◽  
Assessment Model ◽  
Evaluation Tool ◽  
South Central ◽  
P Sources

Soil phosphorus (P) built up due to past management practices, legacy P, in the Lake Okeechobee Watershed (LOW) in south-central Florida, U.S.A., is often discussed as the root cause of lake eutrophication. Improvement of the lake’s water quality requires the identification of critical P sources and quantifying their contributions. We performed a global sensitivity analysis of the Watershed Assessment Model (WAM), a common evaluation tool in LOW environmental planning, using the Morris method. A pre-calibrated WAM setup (Baseline) of the LOW sub-watershed, Taylor Creek Nubbin Slough (TCNS), was used as a test case. Eight scenarios were formulated to estimate the contributions of various P sources. The Morris analysis indicated that total phosphorus (TP) loads were highly sensitive to legacy P in improved pastures, the major land use covering 46.2% of TCNS. The scenario modeling revealed that legacy P, inorganic fertilizers, and other sources contribute 63%, 10%, and 32%, respectively, to the Baseline TP load of 111.3 metric tons/y to the lake. Improved pastures, dairies, citrus, and field crops are the top TP load contributors. Our results have important implications for water quality improvement plans in the LOW and highlighted the need for accurate spatial mapping of legacy P and incorporation of such information in modeling efforts for watersheds demonstrating legacy P problems.

scholarly journals Definitions of Water Quality: A Survey of Lake-Users of Water Quality-Compromised Lakes

Water ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 2114
Author(s):  
Ashley M. Votruba ◽  
Jessica R. Corman
Keyword(s):  
Water Quality ◽  
Environmental Protection Agency ◽  
Water Clarity ◽  
Agricultural Watershed ◽  
Potential Outcomes ◽  
Washington Dc ◽  
Urban Watershed ◽  
Chemical Parameters ◽  
The Us ◽  
Quality Features

Understanding and defining water quality is an important precursor for influencing pro-environmental behavior and accurately assessing potential outcomes of human–lake interactions. This study surveyed 82 lake-users in Nebraska regarding their definitions of water quality and the importance of various water quality features to determine if lake-users’ definitions align with complex and multi-faceted governmental and scientific definitions. Survey sites included two recreational reservoirs (e.g., boating and fishing), Holmes Lake (urban watershed) and Branched Oak Lake (agricultural watershed). The biological and chemical parameters are similar between the lakes and both lakes were listed as “impaired” on the Section 303(d) (United States Environmental Protection Agency, Washington, DC, USA) list of impaired waters of the US at the time of the surveys. The results of our survey suggest that the overwhelming majority of lake-users’ self-generated definitions of water quality did not include more than one feature of water quality found in the relevant policy and regulatory definitions and they focused primarily on water clarity. Further, when provided a list of specific water quality features, the participants rated all provided features of water quality as highly important. This suggests that the failure to include those features in a self-generated definition is not the consequence of perceiving that feature as low importance.

scholarly journals Internal loading potential of phosphorus in reservoirs along a semiarid watershed

RBRH ◽  
2020 ◽  
Vol 25 ◽  
Author(s):  
Diana Souza Moura ◽  
Antonia Samylla Oliveira De Almeida ◽  
Carlos João Pestana ◽  
Laura Gomes Girão ◽  
José Capelo-Neto
Keyword(s):  
Water Quality ◽  
Total Phosphorus ◽  
Nutrient Dynamics ◽  
Internal Loading ◽  
Phosphorus Loading ◽  
Chemical Fractionation ◽  
Phosphorus Concentration ◽  
Ph Values ◽  
Upstream Reservoir ◽  
Artificial Reservoirs

ABSTRACT Sediments are important to nutrient dynamics, especially due to phosphorus internal loading. Several studies have observed that internal loading could prevent water quality from improving in lakes, even when external phosphorus loading is significantly decreased. Therefore, there is an urgent need to assess the potential release of phosphorus contained in the sediment, and thus, its potential to impact water quality. In this study, the vertical and horizontal distributions of distinct phosphorus forms in the bottom sediments of artificial reservoirs, located at Forquilha watershed (Ceará, Brazil), were investigated through sequential chemical fractionation. The reservoirs Lagoa Cercada (R#1), Riacho do Algodão (R#2), Riacho Verde (R#3), Cachoeira (R#4), Chagas Manu (R#5), Quandu (R#6) and Balanças (R#7) were investigated. Reservoirs R#1 (most downstream reservoir of the watershed) and R#7 (most upstream reservoir of the watershed) had higher concentrations of total phosphorus (PT) and lower pH values, potentially exerting greater influence in phosphorus concentration in the water column. Reservoirs R#3 and R#4 presented a predominance of residual phosphorus (PRe), the least available fractions of phosphorus and thus, presented a lower potential for internal loading. Reservoirs R#5, R#1 and R#2 showed a tendency of decreasing total phosphorus (PT) as the sediment depth increased, probably indicating an increase of allochthonous phosphorus loading along time. Reservoir R#6 showed the predominance of PFeAl and PCa fractions on points A and B, respectively, showing that the characteristics of the sediments may vary in the same reservoir. Mobile (PM) and iron and aluminum-bound phosphorus (PFeAl) were the least and the most abundant fractions in most of the samples analyzed, respectively.

Water Quality in the Priority Watercourses of Hong Kong in Respect of Various Environmental Control Measures

1991 ◽  
Vol 23 (1-3) ◽  
pp. 85-91 ◽  
Author(s):  
Ho Kin-chung
Keyword(s):  
Water Quality ◽  
Hong Kong ◽  
Environmental Control ◽  
Control Measures ◽  
Livestock Waste ◽  
Water Control ◽  
Control Zone ◽  
Town Development ◽  
Control Scheme ◽  
Term Monitoring

The water quality in the 12 priority watercourses of Hong Kong was appraised in respect of the various environmental control measures being undertaken. It was noted that water quality in Lam Tsuen River had been significantly improved since 1983. This is attributed to recent resumption of unsewered lands for town development, training of river basin to increase flow, and declaration of the catchment as a “Water Control Zone” under the Water Pollution Control Ordinance. In contrast with the other heavily polluted watercourses to which little abatement measures were implemented, the water qualities of Shing Mun River and Tuen Mun River were slightly upgraded because of the efforts to rectify unauthorized industrial discharges back to foul sewer and provision of interceptors and sewers to villages. The 10 year Livestock Waste Control Scheme enforced on 24 June 1989 was found in parallel with BOD and suspended solids decrease in watercourses. To assess its effectiveness, however, a longer term monitoring is required to get a conclusive result.

What's it Worth? Improving Surface Water Quality

1999 ◽  
Vol 40 (10) ◽  
pp. 153-159 ◽  
Author(s):  
D. H. Newsome ◽  
C. D. Stephen
Keyword(s):  
Water Quality ◽  
Surface Water ◽  
Cost Benefit Analysis ◽  
Cost Benefit ◽  
Surface Water Quality ◽  
Control Measures ◽  
Benefit Analysis ◽  
The Cost

Many countries are investing in measures to improve surface water quality, but the investment programmes for so doing are increasingly becoming subject to cost-benefit analysis. Whilst the cost of control measures can usually be determined for individual improvement schemes, there are currently no established procedures for valuing the benefits attributable to improved surface water quality. The paper describes a methodology that has been derived that now makes this possible.

scholarly journals KUALITAS AIR SUNGAI DI KAWASAN WISATA PANTAI PETITENGET, KEROBOKAN KABUPATEN BADUNG BALI

2018 ◽  
Vol 12 (2) ◽  
pp. 226
Author(s):  
Wayan Budiarsa Suyasa ◽  
Sri Kunti Pancadewi G. A ◽  
Iryanti E. Suprihatin ◽  
Dwi Adi Suastuti G. A.
Keyword(s):  
Water Quality ◽  
Structural Changes ◽  
Pollution Index ◽  
Basic Structure ◽  
Physical Damage ◽  
E Coli ◽  
Pollutant Source ◽  
Quality Category ◽  
Index Value ◽  
The Impact

In order to maintain the environmental carrying capacity of coastal tourism, this research was conducted to determine the condition of river water environmental pollution in the Petitenget beach area and pollutant source activities. Determination of water quality is carried out by analyzing the water quality taken at several sampling points in the four rivers that lead to the Petitenget beach. Determined the pollution index value (IP) of the physical chemical and biological pollution parameters. The results showed that the four rivers that flow into the Petitenget Beach area had been contaminated with indications of pH, BOD, COD, ammonia, Coliform and E. coli which exceeded water quality category III class quality (PerGub Bali No 16 Year 2016). The four rivers are included in the criteria of severe contamination. The four rivers have experienced physical damage or structural changes that have very high discharge fluctuations both in quantity and quality. Slimy basic structure, smelly and slum aesthetic waters. While the indication of the impact of pollution is waste water which is directly discharged into the river from hotels, restaurants, homestays, commercial centers and settlements.

scholarly journals Assessment of Trophic Responses of a Reservoir to Seasonal and Annual Variations in Monsoon

Water ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 2117
Author(s):  
Su-mi Kim ◽  
Hyun-su Kim
Keyword(s):  
Water Quality ◽  
Trophic State ◽  
Monsoon Season ◽  
Phytoplankton Growth ◽  
Phosphorus Loading ◽  
Nutrient Concentrations ◽  
Trophic State Index ◽  
Post Monsoon ◽  
Post Monsoon Season ◽  
State Index

The variations in water quality parameters and trophic status of a multipurpose reservoir in response to changing intensity of monsoon rain was investigated by applying a trophic state index deviation (TSID) analysis and an empirical regression model to the data collected in two periods from 2014 to 2017. The reservoir in general maintained mesotrophic conditions, and Carlson’s trophic state index (TSIc) was affected most by TSITP. Nutrient concentrations, particularly phosphorus, did not show strong correlations with precipitation, particularly in the period with weak monsoon, and a significant increase in total phosphorus (TP) was observed in Spring 2015, indicating the possibility of internal phosphorus loading under decreased depth and stability of water body due to a lack of precipitation. TSIChl was higher than TSISD in most data in period 1 when a negligible increase in precipitation was observed in the monsoon season while a significant fraction in period 2 showed the opposite trend. Phytoplankton growth was not limited by nutrient limitation although nutrient ratios (N/P) of most samples were significantly higher than 20, indicating phosphorus-limited condition. TSID and regression analysis indicated that phytoplankton growth was limited by zooplankton grazing in the Spring, and that cell concentrations and community structure in the monsoon and post-monsoon season were controlled by the changing intensity of the monsoon, as evidenced by the positive and negative relationships between community size and cyanobacterial population with the amount of precipitation in the Summer, respectively. The possibility of contribution from internal loading and an increase in cyanobacterial population associated with weak monsoon, in addition to potential for nutrient enrichment in the post-monsoon season, implies a need for the application of more stringent water quality management in the reservoir that can handle all potential scenarios of eutrophication.

scholarly journals The Dynamic Impacts of the COVID-19 Pandemic on Log Prices in China: An Analysis Based on the TVP-VAR Model

Forests ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 449
Author(s):  
Chenlu Tao ◽  
Gang Diao ◽  
Baodong Cheng
Keyword(s):  
Exchange Rate ◽  
Structural Changes ◽  
Raw Materials ◽  
Supply And Demand ◽  
Oil Prices ◽  
Control Measures ◽  
Var Model ◽  
Time Varying ◽  
Wood Industry ◽  
The Impact

China’s wood industry is vulnerable to the COVID-19 pandemic since wood raw materials and sales of products are dependent on the international market. This study seeks to explore the speed of log price recovery under different control measures, and to perhaps find a better way to respond to the pandemic. With the daily data, we utilized the time-varying parameter autoregressive (TVP-VAR) model, which can incorporate structural changes in emergencies into the model through time-varying parameters, to estimate the dynamic impact of the pandemic on log prices at different time points. We found that the impact of the pandemic on oil prices and Renminbi exchange rate is synchronized with the severity of the pandemic, and the ascending in the exchange rate would lead to an increase in log prices, while oil prices would not. Moreover, the impulse response in June converged faster than in February 2020. Thus, partial quarantine is effective. However, the pandemic’s impact on log prices is not consistent with changes of the pandemic. After the pandemic eased in June 2020, the impact of the pandemic on log prices remained increasing. This means that the COVID-19 pandemic has long-term influences on the wood industry, and the work resumption was not smooth, thus the imbalance between supply and demand should be resolved as soon as possible. Therefore, it is necessary to promote the development of the domestic wood market and realize a “dual circulation” strategy as the pandemic becomes a “new normal”.

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