Mapping areas at risk of diffuse phosphorus losses to water: a pilot study of Lake Haderslev Dam, Denmark

2008 ◽  
Vol 58 (11) ◽  
pp. 2173-2178 ◽  
Author(s):  
Hans Estrup Andersen ◽  
Goswin Heckrath ◽  
Hans Thodsen

Haderslev Dam is a 272 ha lake in southern Denmark with a high recreational value. For decades the lake has been severely eutrophicated due to excessive phosphorus loading. Major point sources were cut off in the early 1990s and an upstream wetland was recreated. However, the ecological quality remains unsatisfactory. In this study we estimate the importance of agriculture on diffuse phosphorus (P) input to the lake by modelling combined with independent estimates for contributions from scattered dwellings not connected to a sewer and from background losses. We apply a newly developed Danish P index to the lake catchment for mapping of risk areas for diffuse phosphorus losses. For risk areas we suggest mitigation measures and estimate the effect of the mitigation measures on the total P loading of the lake as well as the associated costs.

1996 ◽  
Vol 33 (4-5) ◽  
pp. 81-88 ◽  
Author(s):  
B. Kronvang ◽  
P. Græsbøll ◽  
S. E. Larsen ◽  
L. M Svendsen ◽  
H. E. Andersen

Since 1989, nutrient loading of the Danish aquatic environment has been monitored in 270 Danish streams draining catchment areas differing in climate, physico-geographic and land usage. Diffuse nutrient loading from non-point sources (mainly agricultural) is now the main cause of eutrophication of the Danish aquatic environment; thus in 1993, diffuse sources accounted for 94% of riverine nitrogen loading and 52% of riverine phosphorus loading. Annual riverine total nitrogen (total-N) loading from diffuse sources during the period 1989-93 was on average 10 times greater in 66 small agricultural catchments (median 23.4 kg N ha−1) than in 9 natural catchments (median 2.2 kg N ha−1). Correspondingly, annual riverine total phosphorus (total-P) loading from diffuse sources was on average 3.5 times greater in the agricultural catchments (0.29 kg P ha−1) than in the natural catchments (0.07 kg P ha−1). The annual total-N and total-P load was found to increase with the proportion of agricultural land in the catchments. In 1993, intensive measurements of phosphorus load in 8 agricultural catchments showed that normal point sampling (fortnightly) underestimates annual total-P loading by a median of 37% as compared to that estimated by frequent sampling. Moreover, estimates of monthly total-P loading are even more biased, especially in late summer and early autumn (−50% to −65%).


2012 ◽  
Vol 21 (3) ◽  
pp. 307-324 ◽  
Author(s):  
Antti Iho ◽  
Marita Laukkanen

This study analyzes the economic feasibility of gypsum amendment as a means to reduce particulate and dissolved phosphorus loads from arable areas. To this end, an optimization model is developed that includes gypsum amendment as well as matching phosphorus fertilization to crop need and the level of soil phosphorus reserves as phosphorus load mitigation measures, with soil phosphorus reserves measured by soil test phosphorus (STP). The optimal extent of gypsum amendment is then determined simultaneously with optimal fertilization use as a function of field STP level. The results indicate that whether or not gypsum amendment is economically feasible depends on field erosion susceptibility and STP level. When accounting for the costs and benefits to the society on the whole, gypsum treatment suits best to mitigation of phosphorus losses from soils with excessively high phosphorus reserves; once a threshold STP level is reached, gypsum amendment is optimally given up. This threshold level depends on field slope and on society’s willingness to pay for water quality.


AMBIO ◽  
2015 ◽  
Vol 44 (7) ◽  
pp. 612-623 ◽  
Author(s):  
Ana Villa ◽  
Faruk Djodjic ◽  
Lars Bergström ◽  
Katarina Kyllmar

1996 ◽  
Vol 33 (4-5) ◽  
pp. 137-144 ◽  
Author(s):  
Josef Hejzlar ◽  
Vojtech Vyhnálek ◽  
Jirí Kopácek ◽  
Jirí Duras

Export and sources of P in the Vltava basin (subbasin of upper Elbe: total area – 28,093 km2; population density – 115 km−2; forests – 35%, farmland – 51%) were evaluated during 1972–1993. Annual export rates of total P from the basin to the river Elbe ranged between 38 and 68 kg km−2 a−1. Reservoirs with hydraulic retention times longer than 15 days were efficient traps for phosphorus retaining 20 to 30% of total P loading into the watercourses. Point sources (municipal wastewaters) were most important throughout the period and their share varied from approximately 60% in wet years to more than 90% in dry years. Export from diffuse sources (dominated by output from farmland) was highly dependent on discharge and fluctuaded between 5 and 40 kg km−2 a−1 in dry and wet years, respectively. Only about 2% of the P input into the basin from the fertilisation of farmland and from the atmospheric deposition was exported to the watercourses.


Impact ◽  
2020 ◽  
Vol 2020 (3) ◽  
pp. 26-28
Author(s):  
Tsukasa Ohba

Volcanology is an extremely important scientific discipline. Shedding light on how and why volcanoes erupt, how eruptions can be predicted and their impact on humans and the environment is crucial to public safety, economies and businesses. Understanding volcanoes means eruptions can be anticipated and at-risk communities can be forewarned, enabling them to implement mitigation measures. Professor Tsukasa Ohba is a scientist based at the Graduate School of International Resource Studies, Akita University, Japan, and specialises in volcanology and petrology. Ohba and his team are focusing on volcanic phenomena including: phreatic eruptions (a steam-driven eruption driven by the heat from magma interacting with water); lahar (volcanic mudflow); and monogenetic basalt eruptions (which consist of a group of small monogenetic volcanoes, each of which erupts only once). The researchers are working to understand the mechanisms of these phenomena using Petrology. Petrology is one of the traditional methods in volcanology but has not been applied to disastrous eruptions before. The teams research will contribute to volcanic hazard mitigation.


Author(s):  
P. G. Whitehead ◽  
J. Crossman ◽  
B. B. Balana ◽  
M. N. Futter ◽  
S. Comber ◽  
...  

The catchment of the River Thames, the principal river system in southern England, provides the main water supply for London but is highly vulnerable to changes in climate, land use and population. The river is eutrophic with significant algal blooms with phosphorus assumed to be the primary chemical indicator of ecosystem health. In the Thames Basin, phosphorus is available from point sources such as wastewater treatment plants and from diffuse sources such as agriculture. In order to predict vulnerability to future change, the integrated catchments model for phosphorus (INCA-P) has been applied to the river basin and used to assess the cost-effectiveness of a range of mitigation and adaptation strategies. It is shown that scenarios of future climate and land-use change will exacerbate the water quality problems, but a range of mitigation measures can improve the situation. A cost-effectiveness study has been undertaken to compare the economic benefits of each mitigation measure and to assess the phosphorus reductions achieved. The most effective strategy is to reduce fertilizer use by 20% together with the treatment of effluent to a high standard. Such measures will reduce the instream phosphorus concentrations to close to the EU Water Framework Directive target for the Thames.


2019 ◽  
Vol 60 (1) ◽  
pp. 50-58 ◽  
Author(s):  
Anneleen Dereymaeker ◽  
Vladimir Matic ◽  
Jan Vervisch ◽  
Perumpillichira J. Cherian ◽  
Amir H. Ansari ◽  
...  

2021 ◽  
Author(s):  
Sophie de Bruin ◽  
Jannis Hoch ◽  
Nina von Uexkull ◽  
Halvard Buhaug ◽  
Nico Wanders

<p>The socioeconomic impacts of changes in climate-related and hydrology-related factors are increasingly acknowledged to affect the on-set of violent conflict. Full consensus upon the general mechanisms linking these factors with conflict is, however, still limited. The absence of full understanding of the non-linearities between all components and the lack of sufficient data make it therefore hard to address violent conflict risk on the long-term. </p><p>Although it is neither desirable nor feasible to make exact predictions, projections are a viable means to provide insights into potential future conflict risks and uncertainties thereof. Hence, making different projections is a legitimate way to deal with and understand these uncertainties, since the construction of diverse scenarios delivers insights into possible realizations of the future.  </p><p>Through machine learning techniques, we (re)assess the major drivers of conflict for the current situation in Africa, which are then applied to project the regions-at-risk following different scenarios. The model shows to accurately reproduce observed historic patterns leading to a high ROC score of 0.91. We show that socio-economic factors are most dominant when projecting conflicts over the African continent. The projections show that there is an overall reduction in conflict risk as a result of increased economic welfare that offsets the adverse impacts of climate change and hydrologic variables. It must be noted, however, that these projections are based on current relations. In case the relations of drivers and conflict change in the future, the resulting regions-at-risk may change too.   By identifying the most prominent drivers, conflict risk mitigation measures can be tuned more accurately to reduce the direct and indirect consequences of climate change on the population in Africa. As new and improved data becomes available, the model can be updated for more robust projections of conflict risk in Africa under climate change.</p>


Author(s):  
Christine Olney ◽  
Jennifer Leestma ◽  
Andrew Hansen ◽  
John Ferguson ◽  
Mary Murphy Kruse ◽  
...  

Veterans with spinal cord injury (SCI) are at high risk for developing debilitating pressure injuries, particularly to their seated areas (e.g. coccyx, sacral and gluteal) [1]. To prevent development of a pressure injury the Veteran with SCI is encouraged to invoke multiple prevention strategies [2]. One recommended prevention strategy is to conduct twice daily skin self-screenings. Skin self-screening is usually conducted in the bed, prior to arising in the morning and prior to sleep in the evening. The current method to conduct skin self-screening utilizes a mirror at the end of a long handle. The Veteran with SCI examines at-risk areas for changes in their skin integrity such as discoloration, swelling, or changes in skin texture. This method can take up to 20 minutes to complete. In the event there is a change to skin integrity, the pressure injury prevention protocol advises the Veteran with SCI to off-load that particular area for at least 24 hours [3]. Further, he/she is advised to consult with their skin specialist if the area does not resolve to normal color or texture within that next 24 hour period. The consequences of ignoring an early stage pressure injury can be serious e.g. weeks to months of hospitalization attempting to heal the injury, tens to hundreds of thousands of dollars in healthcare costs, possible surgery to close the wound and possibly death [4]. Informal interviews with Veterans with SCI clarified and validated that conducting skin screening with the mirror could be very challenging due to barriers such as: not having a baseline image to compare to; the mirror image not being viewable to the user due to lack of user flexibility or body habitus; the mirror does not easily allow a complete view of all the at-risk areas; the user not being able to discern what he/she is actually viewing possibly due to mirror image distortion and limited visual acuity. The need for a better skin self-screening device was evidenced by the advanced pressure injuries Veterans presented to their healthcare providers. Finding a pressure injury in the early stages of development and intervening immediately, such as repositioning, can improve the trajectory of the injury [5]. Therefore the project goal was to offer a better tool for and improve the efficacy of skin self-screening for the Veterans with SCI. To overcome the identified barriers, our team of VA clinicians and engineers of the Minneapolis Adaptive Design & Engineering (MADE) program invented such a device at the Minneapolis VA. This paper presents the patient centered iterative process that was used to develop a skin self-screening device and the future directions for this technology.


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