scholarly journals Assessing the Eutrophic Susceptibility of New Zealand Estuaries

2020 ◽  
Vol 43 (8) ◽  
pp. 2015-2033 ◽  
Author(s):  
David R. Plew ◽  
John R. Zeldis ◽  
Bruce D. Dudley ◽  
Amy L. Whitehead ◽  
Leigh M. Stevens ◽  
...  
Keyword(s):  
Land Use ◽  
New Zealand ◽  
Physical Properties ◽  
Nutrient Loading ◽  
Management Strategies ◽  
Nutrient Concentrations ◽  
Intertidal Area ◽  
Land Use Patterns ◽  
Regional Patterns ◽  
Nitrogen Concentrations

Abstract We developed a method to predict the susceptibility of New Zealand estuaries to eutrophication. This method predicts macroalgae and phytoplankton responses to potential nutrient concentrations and flushing times, obtained nationally from simple dilution models, a GIS land-use model and physical estuary properties. Macroalgal response was based on an empirically derived relationship between potential nitrogen concentrations and an established macroalgal index (EQR) and phytoplankton response using an analytical growth model. Intertidal area was used to determine which primary producer was likely to lead to eutrophic conditions within estuaries. We calculated the eutrophication susceptibility of 399 New Zealand estuaries and assigned them to susceptibility bands A (lowest expected impact) to D (highest expected impact). Twenty-seven percent of New Zealand estuaries have high or very high eutrophication susceptibilities (band C or D), mostly (63% of band C and D) due to macroalgae. The physical properties of estuaries strongly influence susceptibility to macroalgae or phytoplankton blooms, and estuaries with similar physical properties cluster spatially around New Zealand’s coasts. As a result, regional patterns in susceptibility are apparent due to a combination of estuary types and land use patterns. The few areas in New Zealand with consistently low estuary eutrophication susceptibilities are either undeveloped or have estuaries with short flushing times, low intertidal area and/or minimal tidal influx. Estuaries with conditions favourable for macroalgae are most at risk. Our approach provides estuary-integrated susceptibility scores likely to be of use as a regional or national screening tool to prioritise more in-depth estuary assessments, to evaluate likely responses to altered nutrient loading regimes and assist in developing management strategies for estuaries.

Scale, context, and application of traditional knowledge of the Canadian north

Polar Record ◽  
1998 ◽  
Vol 34 (188) ◽  
pp. 31-38 ◽  
Author(s):  
Frank Duerden ◽  
Richard G. Kuhn
Keyword(s):  
Land Use ◽  
Resource Management ◽  
Land Use Planning ◽  
Management Strategies ◽  
Primary Role ◽  
Land Claims ◽  
Land Use Patterns ◽  
Use Patterns ◽  
Physical Environments ◽  
The Many

AbstractThere is strong contemporary interest in the application of traditional environmental knowledge (TEK) of physical environments and land-use patterns in northern Canada. This interest relates to land claims, land-use planning, cultural preservation, resource management, and environmental monitoring. The application of TEK to land and resource management is critically examined and a typology relating scale, user group, and the transformation of knowledge is developed. Of the many challenges facing the incorporation of TEK in resource-management initiatives, perhaps the greatest is the recognition of the appropriateness of scale. The conclusions reached in this paper reaffirm the notion that scale and context are key components in maintaining the validity and integrity of TEK. The primary role of TEK appears to be with providing the most valid and intelligible interpretations of local geographies and prescribing locally appropriate resource-management strategies.

scholarly journals Domestic Cat Abundance and Activity Across a Residential Land Use Gradient

2021 ◽  
Vol 9 ◽  
Author(s):  
Kevin F. P. Bennett ◽  
Brian S. Evans ◽  
J. Alan Clark ◽  
Peter P. Marra
Keyword(s):  
Land Use ◽  
Native Species ◽  
Management Strategies ◽  
Urban Environments ◽  
Camera Traps ◽  
Domestic Cat ◽  
Land Use Patterns ◽  
Residential Land ◽  
Residential Land Use ◽  
Free Ranging

Free-ranging domestic cats are a detriment to wildlife and humans by preying on native species and transmitting disease. As a result, removing free-ranging cats from the landscape has become a conservation and public health priority. Estimating cat population size with an unbiased sampling design, however, especially in human-dominated areas, is logistically challenging and rarely done. The lack of robust cat population sampling limits our understanding of where cats pose risks, which is important for evaluating management strategies, such as trap-remove or trap-neuter-return. We hypothesized that cat abundance and activity both depend on human land use and demographics. Using a network of sites participating in a community science program, we conducted transect and camera trap surveys to test predictions of cat population abundance and activity across a gradient of residential land use intensity. Both sampling methods determined that cat abundance was greatest in areas with intermediate human population density and lower educational attainment. Transect data also provided evidence that cat abundance was greatest at intermediate levels of impervious surface cover (e.g., road and buildings), while data from camera traps also showed that cat abundance was positively associated with household income. Using counts of cats observed on cameras, we found that the timing of cat activity varied depending on the degree of urban intensity. Cats were more strictly nocturnal in medium and high intensity residential land-use areas, possibly because a greater proportion of these cats are unowned or because they avoid human activity. These results suggest that transect surveys conducted during the day may undercount cats in urban environments where unowned free-ranging cats predominate. Taken together, our results highlight the importance of incorporating human demographics, land use patterns, and urban context in estimating the abundance of free-ranging cats to better inform management decisions and improve conservation outcomes.

scholarly journals Quantifying the nutrient flux within a lowland karstic catchment

2015 ◽  
Vol 12 (10) ◽  
pp. 10221-10260
Author(s):  
T. McCormack ◽  
O. Naughton ◽  
P. M. Johnston ◽  
L. W. Gill
Keyword(s):  
Nutrient Loading ◽  
Hydrological Model ◽  
Nutrient Flux ◽  
Agricultural Runoff ◽  
Nutrient Loss ◽  
Nutrient Concentrations ◽  
Main Process ◽  
Stable Conditions ◽  
Nitrogen Concentrations ◽  
Hydrological Functioning

Abstract. Nutrient contamination of surface and groundwaters is an issue of growing importance as the risks associated with agricultural runoff escalate due to increasing demands on global food production. In this study, the nutrient flux occurring within the surface and groundwaters of a lowland karst catchment in western Ireland was investigated with the aid of alkalinity sampling and a hydrological model. Water samples were tested from a variety of rivers, lakes (or turloughs), boreholes and springs at monthly intervals over three years. Alkalinity sampling was used to elucidate the contrasting hydrological functioning between different turloughs. Such disparate hydrological functioning was further investigated with the aid of a hydrological model which allowed for an estimate of allogenic and autogenic derived nutrient loading into the karst system. The model also allowed for an investigation of mixing within the turloughs, comparing observed behaviours with the hypothetical conservative behaviour allowed for by the model. Within the turloughs, nutrient concentrations were found to reduce over the flooded period, even though the turloughs hydrological functioning (and the hydrological model) suggested this should not occur. As such, it was determined that nutrient loss processes were occurring within the system. Denitrification during stable flooded periods (typically 3–4 months per year) was deemed to be the main process reducing nitrogen concentrations within the turloughs whereas phosphorus loss is thought to occur mostly via sedimentation and subsequent soil deposition. The results from this study suggest that, in stable conditions, ephemeral lakes can impart considerable nutrient losses on a karst groundwater system.

scholarly journals Variations of the nutrient concentrations in the sediments of ponds under the slopes of different land use patterns in small red soil watershed

2006 ◽  
Vol 18 (4) ◽  
pp. 387-394
Author(s):  
WANG Xiaolong ◽  
◽  
HU Feng ◽  
LI Huixing ◽  
QIN Jiangtao ◽  
...  
Keyword(s):  
Land Use ◽  
Red Soil ◽  
Nutrient Concentrations ◽  
Land Use Patterns ◽  
Use Patterns

scholarly journals Assessment of Terrigenous Nutrient Loading to Coastal Ecosystems along a Human Land-Use Gradient, Tutuila, American Samoa

Hydrology ◽  
2019 ◽  
Vol 6 (1) ◽  
pp. 18 ◽  
Author(s):  
Christopher Shuler ◽  
Daniel Amato ◽  
Veronica Veronica Gibson ◽  
Lydia Baker ◽  
Ashley Olguin ◽  
...  
Keyword(s):  
Land Use ◽  
Nutrient Loading ◽  
Water Discharge ◽  
Nitrogen Isotope ◽  
Nutrient Flux ◽  
American Samoa ◽  
Nutrient Concentrations ◽  
Human Land Use ◽  
The Impact

Anthropogenic nutrient loading is well recognized as a stressor to coastal ecosystem health. However, resource managers are often focused on addressing point source or surface water discharge, whereas the impact of submarine groundwater discharge (SGD) as a nutrient vector is often unappreciated. This study examines connections between land use and nutrient loading through comparison of four watersheds and embayments spanning a gradient of human use impact on Tutuila, a high tropical oceanic island in American Samoa. In each study location, coastal radon-222 measurements, dissolved nutrient concentrations, and nitrogen isotope values (δ15N) in water and in situ macroalgal tissue were used to explore SGD and baseflow derived nutrient impacts, and to determine probable nutrient sources. In addition to sampling in situ macroalgae, pre-treated macroalgal specimens were deployed throughout each embayment to uptake ambient nutrients and provide a standardized assessment of differences between locations. Results show SGD-derived nutrient flux was more significant than baseflow nutrient flux in all watersheds, and δ15N values in water and algae suggested wastewater or manure are likely sources of elevated nutrient levels. While nutrient loading correlated well with expected anthropogenic impact, other factors such as differences in hydrogeology, distribution of development, and wastewater infrastructure also likely play a role in the visibility of impacts in each watershed.

scholarly journals Modelling water, sediment and nutrient fluxes from a mixed land-use catchment in New Zealand: effects of hydrologic conditions on SWAT model performance

2015 ◽  
Vol 12 (4) ◽  
pp. 4315-4352 ◽  
Author(s):  
W. Me ◽  
J. M. Abell ◽  
D. P. Hamilton
Keyword(s):  
Land Use ◽  
New Zealand ◽  
High Frequency ◽  
Swat Model ◽  
Base Flow ◽  
Treated Wastewater ◽  
Nutrient Concentrations ◽  
Flow Measurements ◽  
Event Based ◽  
Parameter Values

Abstract. The Soil Water Assessment Tool (SWAT) was configured for the Puarenga Stream catchment (77 km2), Rotorua, New Zealand. The catchment land use is mostly plantation forest, some of which is spray-irrigated with treated wastewater. A Sequential Uncertainty Fitting (SUFI-2) procedure was used to auto-calibrate unknown parameter values in the SWAT model which was applied to the Puarenga catchment. Discharge, sediment, and nutrient variables were then partitioned into two components (base flow and quick flow) based on hydrograph separation. A manual procedure (one-at a-time sensitivity analysis) was then used to quantify parameter sensitivity for the two hydrologically-separated regimes. Comparison of simulated daily mean discharge, sediment and nutrient concentrations with high-frequency, event-based measurements allowed the error in model predictions to be quantified. This comparison highlighted the potential for model error associated with quick-flow fluxes in flashy lower-order streams to be underestimated compared with low-frequency (e.g. monthly) measurements derived predominantly from base flow measurements. To overcome this problem we advocate the use of high-frequency, event-based monitoring data during calibration and dynamic parameter values with some dependence on discharge regime. This study has important implications for quantifying uncertainty in hydrological models, particularly for studies where model simulations are used to simulate responses of stream discharge and composition to changes in irrigation and land management.

scholarly journals Climate change adaptation in arable land use, and impact on nitrogen load at catchment scale in northern agriculture

2013 ◽  
Vol 22 (3) ◽  
pp. 342-355 ◽  
Author(s):  
Katri Rankinen ◽  
Pirjo Peltonen-Sainio ◽  
Kirsti Granlund ◽  
Hannu Ojanen ◽  
Mikko Laapas ◽  
...  
Keyword(s):  
Climate Change ◽  
Land Use ◽  
Crop Production ◽  
Nutrient Loading ◽  
Arable Land ◽  
System Level ◽  
Adaptation To Climate Change ◽  
Catchment Scale ◽  
Land Use Patterns ◽  
Arable Land Use

Prolongation of the growing season due to a warming climate could represent new opportunities for northern agriculture. Climatic and biotic constraints may challenge future crop production. The objective of this study was to speculate how a range of arable land use patterns, resulting from various policy driven choices, could be introduced into a farming system, and how they would affect the risks associated with nutrient leaching. We found that while adaptation to climate change must include consideration of crop choices, there are conflicts associated with allocations and rotations for various market and policy situations. The expected increase in nutrient loading in the simulations caused by climate change was moderate. The increase can partly be compensated for by changes in farmland use, more in the shorter term than in the longer term to mid-century. In the future, adaptation at cropping system level is potentially an efficient way to manage nutrient load risks.

scholarly journals Fecal Contamination and High Nutrient Levels Pollute the Watersheds of Wujiang, China

Water ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 457
Author(s):  
Raju Sekar ◽  
Xin Jin ◽  
Shuang Liu ◽  
Jing Lu ◽  
Jianwei Shen ◽  
...  
Keyword(s):  
Water Quality ◽  
Land Use ◽  
Management Strategies ◽  
Fecal Contamination ◽  
Water Quality Monitoring ◽  
Ammonium Nitrogen ◽  
Point Sources ◽  
Fecal Coliforms ◽  
Land Use Patterns ◽  
Sources Of Pollution

Freshwaters in China are affected by point and non-point sources of pollution. The Wujiang District (Suzhou City, China) has a long history of canals, rivers, and lakes that are currently facing various water quality issues. In this study, the water quality of four rivers and a lake in Wujiang was assessed to quantify pollution and explore its causes. Seventy-five monthly samples were collected from these water bodies (five locations/samples per area) from August to October 2020 and were compared with nine control samples collected from a water protection area. Fifteen physicochemical, microbiological, and molecular–microbiological parameters were analyzed, including nutrients, total and fecal coliforms, and fecal markers. Significant monthly variation was observed for most parameters at all areas. Total phosphorus, phosphates, total nitrogen, ammonium–nitrogen, and fecal coliforms mostly exceeded the acceptable limits set by the Chinese Ministry of Environmental Protection. The LiPuDang Lake and the WuFangGang River were the most degraded areas. The studied parameters were correlated with urban, agricultural, industrial, and other major land use patterns. The results suggest that fecal contamination and nutrients, associated with certain land use practices, are the primary pollution factors in the Wujiang District. Detailed water quality monitoring and targeted management strategies are necessary to control pollution in Wujiang’s watersheds.

Loading rates of nutrients discharging from a golf course and a neighboring forested basin

1999 ◽  
Vol 39 (12) ◽  
pp. 99-107 ◽  
Author(s):  
Takao Kunimatsu ◽  
Miki Sudo ◽  
Takeshi Kawachi
Keyword(s):  
Nutrient Loading ◽  
Chamaecyparis Obtusa ◽  
Phosphorus Loading ◽  
Golf Course ◽  
Nutrient Concentrations ◽  
Golf Courses ◽  
Japanese Cypress ◽  
Arithmetic Average ◽  
Loading Rates ◽  
Runoff Rate

In the last ten years, the number of golf courses has been increasing in some countries as the game gains popularity. This indicates, a need to estimate the nutrient loading from golf courses in order to prevent the eutrophication of water bodies. Nutrient concentrations and flow rates of a brook were measured once a week from 1989 to 1990 at two sites: Site A of a brook flowing out from D-golf course (53 ha) and Site B of the same brook discharging into the golf course from an upper forested basin (23 ha) covered mainly with planted Japanese cypress (Chamaecyparis obtusa SIEB. et ZUCC). The bedrock of the area was granite. The annual values of precipitation and mean temperature were 1947 mm and 13.5°C in 1989, respectively. The arithmetic average values of discharge from the forested basin and the golf course were 0.392 and 1.26 mg/l total nitrogen (TN), 0.0072 and 0.145 mg/l total phosphorus (TP), 0.82 and 3.53 mg/l potassium ion (K+, 5.92 and 8.24 mg/l sodium ion (Na+), 2.1 and 9.9 mg/l suspending solid (0.001–2.0 mm, SS), 0.087 and 0.147 mS/cm electric conductivity (EC), and 0.031 and 0.037 m3/km2•s specific discharge, respectively. The loading rates of the forested basin and the golf course were 5.42 and 13.5 TN, 0.133 and 3.04 TP, 8.84 and 33.9 K+, 55.0 and 73.0 Na+, and 54.3 and 118 SS in kg/ha•y. The leaching and runoff rate of nitrogen in the chemical fertilizers applied on the golf course was calculated as 32%. These results indicated the importance of controlling the phosphorus loading for the management of golf courses.

IMPACTS OF URBAN LAND USE ON CRIME PATTERNS THROUGH GIS APPLICATION

2013 ◽  
Vol 11 (2) ◽  
Author(s):  
Ahmad Nazri Muhamad Ludin ◽  
Norsiah Abd. Aziz ◽  
Nooraini Hj Yusoff ◽  
Wan Juliyana Wan Abd Razak
Keyword(s):  
Land Use ◽  
Drug Abuse ◽  
Land Use Planning ◽  
Urban Areas ◽  
Spatial Relationship ◽  
Police Department ◽  
Strong Relationship ◽  
Urban Land ◽  
Urban Land Use ◽  
Land Use Patterns

Land use planning plays a crucial role in creating a balance between the needs of society, physical development and the ecosystem. However, most often poor planning and displacement of land uses particularly in urban areas contribute to social ills such as drug abuse and criminal activities. This research explains the spatial relationship of drug abuse and other criminal activities on urban land use planning and their implications on the society at large. Spatial statistics was used to show patterns, trends and spatial relationships of crimes and land use planning. Data on crime incidents were obtained from the Royal Malaysia Police Department whilst cases of drug abuse were collected from the National Anti-Drug Agency (AADK). Analysis of the data together with digital land use maps produced by Arnpang Jaya Municipal Council, showed the distribution of crime incidents and drug abuse in the area. Findings of the study also indicated that, there was a strong relationship between petty crimes, drng abuse and land use patterns. These criminal activities tend to concentrate in residential and commercial areas of the study area.

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