ln(beach-litter-density) Found on the beach: Lac Léman 2015 - 2016
A comparison of marine and freshwater litter densities
Introduction
Table of contents
Situation map
Beach litter survey results for Lac Léman Density and composition Transport methods
Results from other organisations and student groups Density distribution OSPAR and Lac Léman
Density and composition OSPAR and Lac Léman Discussion and Conclusion
Limitations and recomendations
Links to references and supporting documents
Marine litter starts upstream, that’s where it needs to end. hammerdirt 2017
Useful acronyms and definitions. For the full text analysis and explanation of the methodology see annex b. • OSPAR: Oslo - Paris convention for the Protection of the Marine Environment of the NorthEast Atlantic. The convention has been signed and ratified by Switzerland.
• MLW: Marine Litter Watch combines citizen engagement and modern technology to help tackle marine litter.
• MSFD: Marine Strategy Framework Directive aims to achieve Good Environmental Status
(GES) of the EU’s marine waters by 2020 and to protect the resource base upon which marine-related economic and social activities depend.
• Beach litter survey: a uniform way of monitoring shoreline litter. Litter is removed from
the shoreline, categorized according to a standardized list and counted. The length and location of the shoreline are noted.
• Standard unit: one meter of shoreline.
• Density: pieces of trash per meter of shoreline • pcs/m: pieces of trash per meter of shoreline
• hammerdirt: The association that started the MCBP series of projects
• MCBP: A series of hammerdirt projects that removes, identifies and quantifies aquatic pollutants. • Lac Léman: Lake Geneva
• Log-normal: A probability distribution of a random variable whose logarithm is normally distributed.
“Marine litter (marine debris) is any persistent, manufactured or processed solid material discarded, disposed of, abandoned or lost in the marine and coastal environment. This also includes such items entering the marine environment via rivers, sewage outlets, storm water outlets or winds.”
OSPAR guide lines 2010
Shoreline litter density on Lac Léman: A litter density comparison between
the shores of Lac Léman and the coasts of France, Denmark, England, Portugal and Belgium. Purpose: identify and quantify the visible pollutants present on the shores of Lac Léman and compare those results to existing data sets from other regions in europe.
Beach litter surveys were conducted at various lo-
Objective: advance the concept of “shoreline litter density” as a metric or module in the appreciation of Swiss lakes and to identify key opportunities for anti-litter campaigns and infrastructure improvements.
Only surveys with a minimum shoreline length of 5 meters and situated directly on the lake-shore were kept for analysis. The resulting eighty samples and 27’790 pieces of trash were converted to units of “pieces of trash per meter” (pcs/m). The total density and density of key items for each location on the lakeshore was calculated and compared. Similarities were noted in the relative proportions of certain key items at all locations.
cations on Lac Léman , Switzerland from November 2015 to November 2016. The hammerdirt association used the Marine Litter Watch (MLW) classification system to categorize over 30’000 items identified in 89 beach litter surveys from 17 locations.
The total density and densities of the most common items were regressed against Rhone discharge rates, precipitation rates and days-between-surveys. Statistically significant results were found for total density, Q-tips and plastic-construction-material when the 72hour Rhone discharge rate was considered.(annex Conflict of interest: hammerdirt b has the full analysis) has received no financial assisOSPAR and MLW are the most well known marine debris datance from any agency, institutabases in Europe. Designed as a tool to measure the load of tion or individual for this project. marine debris in coastal environments both programs are monitored by intergovernmental organizations and are based on Authors: simple protocols. MCBP2 was based on theses two programs. Erismann, Roger Sorted by location and density, the results from Lac Léman Erismann, Shannon were compared to MLW results for 2016 and 130 OSPAR
[email protected] veys from France, England, Denmark, Portugal and Belgium. The regions and countries were chosen at random. Similarities between the three sample groups were noted in both the distribution of total density and percent composition of key items. Usage: Anybody who wants to know more about aquatic-litter and how they can help stop it.
Two case studies are presented that propose the use of beach-litter survey data to define the problem on a local level and identify root causes of changes in beach-litter density.
“The greatest sources of marine litter are land-based activities, including waste from dumping sites near the coast or upstream along river-banks…” United Nations Environmental Program October 2016: Sorting beach litter debris from St Sulpice with students from the EPFL
Villa Barton
1
• # of surveys: 9 • Total number of pieces: 1’231 • Average density: 9.77 • #of MLW categories: 51 • Length: 14m
Jardin Botanique 2 • # of surveys: 3 • # of pieces: 1’659 • Average density: 8.64 • # of MLW categories: 53 • Length 64m
Versoix
3
• # of surveys: 1 • # of pieces: 1’490 • Average density: 10.41 • Length: 143m
Boiron
St Sulpice
4
• # of surveys: 1 • # of pieces: 402 • Average density: 3.27 • # of MLW categories: 32 • Length: 123m
5
• # of surveys: 2 • # of pieces: 2’ 721 • Average density: 21.3 • # of MLW categories: 35 • Length: 72
Vidy
6
• # of surveys: 1 • # of pieces: 55 • Average density: 6.88 • # of MLW categories: 16 • Length: 8m
Arabie
7
• # of surveys: 3 • # of pieces: 3’154 • Average density: 26.28 • # of MLW categories: 55 • Length: 40m
Survey Locations
Veveyse
8
Oyonne
9
Bain des Dames
10
Port, La Tour-de-Peilz
10
Maladaire
11
Baye de Clarens
12
Pierrier
12
Pierrier sud
12
• # of surveys: 13 • # of pieces: 2’345 • Average density: 3.40 • Density max: 5.8 • Denisty min: 0.98 • # of MLW categories: 67 • Length: 53m
• # of surveys: 1 • # of pieces: 717 • Average density: 22.41 • # of MLW categories: 44 • Length: 32m
The majority of the beach litter surveys come from the Vevey-Montreux area, home to the hammerdirt association. The Baye de Clarens, the Baye de Montreux and the Veveyse were surveyed 52 times during MCBP2.
4
5
6 78 910 11 12 13
Geographically the region of Vevey-Montreux has multiple pressures in regard to aquatic litter:
14
• The mouth of the Rhone is only 6km away
15
• The Stockalper and Eau froide canals empty into the lake • Three rivers that cross urban and semi-urban landscapes
3
• Densely populated
1
The locations outside of the Vevey-Montreux area were chosen based on availability or by request from other groups, like St Sulpice or St Gingolph.
• # of surveys:13 • Total number of pieces: 2’968 • Average density: 3.31 • Density max: 8.41 • Density min: 0.68 • # of MLW categories: 67 • Length: 69m
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Echelle 1: 300,000 Imprimé le 10.10.2016 19:46 https://s.geo.admin.ch/6edb0e8211
© swisstopo
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• # of surveys: 1 • # of pieces: 194 • Average density: 4.04 • # of MLW categories: 34 • Length: 48
St. Gingolph
• # of surveys: 1 • # of pieces: 1’159 • Average density: 41.39 • # of MLW categories: 58 • Length : 28
• # of surveys: 1 • # of pieces: 570 • Average density: 17.81 • # of MLW categories: 26 • Length: 32.00 • # of surveys: 2 • #of pieces: 1’437 • Average density: 11.975 • Density max : 12.21 • Density min: 11.73 • # of MLW categories: 46 • Length: 60
Beach litter surveys Lac Léman Nov 2015 - Nov 2016
Thonon-les-Bains 15
• # of surveys: 1 • # of pieces: 594 • Average density: 34.94 • # of MLW categories: 33 • Length: 17m
14
Baye de Montreux gauche 13 • # of surveys: 11 • # of pieces: 3’098 • Average density: 4.62 • Density max: 8.38 • Density min: 1.23 • # of MLW categories: 67 • Length: 61
• # of surveys: 3 • # of pieces: 2’697 • Average density: 17.63 • Density max: 26.78 • Density min: 11.31 • # of MLW categories: 60 • Length: 51 • # of surveys: 1 • Total number of pieces: 633 • Average density: 39.56 • # of MLW categories: 28 • Length: 16
Baye de Montreux droite 13 • # of surveys: 15 • # of pieces: 5’077 • Average density: 5.45 • Density max: 14.49 • Density min: 1.56 • # of MLW categories: 64 • Length: 61
Beach litter survey results Beach litter composition
Chart 1 displays the 16 MLW categories that are equal to 1% or more of the total number of objects found during MCBP2. 20.7%: Cigarette butts
12.4%: Plastic fragments
85% of total = 16 objects Expanded polystyrene and cigarette butts are present in almost equal values, together these two objects represent 42% of the litter on the shoreline.
6.1%: Snack wrappers
Like the ocean, the debris on the shoreline of the lake is mostly plastic. Chart 1 displays the percentage composition of all the objects found during MCBP2, objects that were greater than or equal to 1% of the total (27’790) were singled out. Table 1 summarizes the material composition of the debris removed from the Lac Léman shoreline and the current MLW results for 2016. Although 88% of the total is plastic, there are many varieties of plastic included in that group, ranging from candy wrappers to shotgun shells (see chart 1). There are 16 MLW categories that comprise 85% of the total debris found on the lake-shore (chart 1). The most common categories identified during the MCBP2 surveys are also among the most common items in the 2016 results from Marine Litter Watch Chart two compares the percent composition of ten key items in the MLW results and the MCBP2 results. The same items occupy a greater percentage of the total in the MCBP2 results. (chart 2)
Chart 2: Beach litter composition: MCBP2 and MLW 2016 results.
1.80%: Paper fragments 1.5%: Shotgun cartridges 1.4%: Plastic lids - type unknown: 1.1%: Pieces of metal < 50cm
14.7%: Everything else
Plastic caps from drinks: 2.1% Waste from construction: 1.8% Metal bottle caps: 1.5% Plastic rings from bottle caps: 1.3%
Drinking straws - drink stirrers : 1.1%
100% Expanded polystyrene Cigarette butts Plastic Fragments Snack Wrappers Cotton swabs Broken glass Plastic caps from drinks Shotgun cartridge Pieces of metal < 50cm Drinking straws and stirrers Everything else
88.1%
91.3%
Metal
4.3%
3.6%
Glass
2.9%
2.0%
Paper
2.9%
0.1%
Rubber
0.7%
0.3%
Wood
0.5%
0.5%
0.2%
2.6%
0.1%
N/A
Cloth textile Parafin
Lac Léman: MCBP2 beach litter survey results.
4.5%: Cotton swabs
2.7%: Broken glass
Plastic
Table 1: Material composition of beach litter surveys Lac Léman / Marine Litter Watch.
88% plastic
Plastic sheeting and films: 4.3%
MLW
21%: Expanded polystyrene
MCBP2
Lac Léman
Chart 1: Percent composition of Lac Léman beach litter by MLW categories. All items that are equal to or greater than 1% of the total quantity. n = 27’790 items collected
80%
60%
40% 20%
0%
Marine Litter Watch: Beach litter survey results 2016.
Density and Composition MCBP2
Chart 3: average density of beach litter and top 16 items by location in descending order of density.
40
n=80 surveys and 17 locations
The average density and composition of the beach litter for all locations is presented in chart 3. Using chart 1 as a model, the same filter was applied to the results for each location. Even at smaller density values the relationship of the key items to total density remains within a certain range. Chart 4 compares the percent composition of objects between all survey locations. Although the densities of individual items varies per location, the category “everything else” stays within a fairly small range.
Weighted average of density: 35
Cigarette butts
Plastic Fragments ExpandedPlastic polystyrene sheeting and films Plastic Fragments Construction waste
Snack Wrappers Plastic caps from drinks
Plastic sheeting and-films Platic lids type unknown
Broken glass Paper fragments
Construction wastecartridge Shotgun Platic lids -Cotton type unknown swabs
Plastic caps frombottle drinkscaps Metal
Shotgun cartridge
Metal bottle caps straws and stirrers Drinking
Cotton swabs
Plastic rings fromofcaps Pieces metal < 50cm
Snack Wrappers Cigarette butts Broken glass
Paper fragments Plastic rings from caps
Drinking straws and stirrers
8.44 pcs/m
47%
Density range :
35%
Pieces of metal < 50cm
100%
80%
60%
40%
Jardin Botanique
Villa Barton
Arabie
Veveyse
Pierrier
Thonon
St. Gingolph
Vidy
Boiron
Pierrier Sud
Le Port, La Tour-de-Peilz
Oyonne
0%
Bain des Dames
20%
Maladaire
St. Gingolph Pierrier Sud Bain des Dames Le Port, La Tour-de-Peilz Arabie Oyonne Pierrier Maladaire Villa Barton Jardin Botanique Vidy Montreux droite Montreux gauche Thonon Veveyse Baye de Clarens Boiron
Expanded polystyrene Cigarette butts Plastic Fragments Snack Wrappers Cotton swabs Plastic sheeting and films Broken glass Plastic caps from drinks Paper fragments Construction waste Shotgun cartridge Metal bottle caps Platic lids - type unknown Plastic rings from caps Pieces of metal < 50cm Drinking straws and stirrers Everything else
Chart four: percent composition of beach litter at each location, Lac Léman 2015-2016
Montreux gauche
5
10
15
20
• 70% of density values between 2.18 - 13.48 pcs/m • Log-normal distribution where μ= 1.689, σ = 0.912
Montreux droite
25
Density distribution :
Baye de Clarens
30
0.68 - 50.1 pcs/m
0
Pieces of trash per meter of shoreline, Lac Léman Nov 2015 - Sep 2016 - n=80
Most likeley left by visitors:
Most likely transported to the location by wind, rain or lake currents : Expanded polystyrene
f yo
sit
n De
sh
tra
on
t
he
h
c ea
b
fQ
b
m Nu
The Rhone and tributaries are the main water sources for the lake and increases in the discharge rate of the Rhone corresponds with trash density increases in the Montreux region. See Annex B.
Students from the “Solid Waste Engineering” class at the EPFL and elementary school students from the international school of Geneva, assisted by hammerdirt staff, completed beach litter surveys in St. Sulpice and Versoix. (Annex B for details) Chart five puts the results from these surveys in relation to the results from MCBP2
35
Allaman
25
Arabie
St Gingolph
St Sulpice
Villa Barton
40
30 Bain des Dames
15
20
Anthy sur Leman
5
10
Oyonne
Baye de Clarens
0
Jardin Botanique
433 pieces or 1.5% of total.
Montreux droite
Shotgun shells
h
ac
be
Chart five: Maximum density per location Lac Léman - comparison of MCBP2 results with results from other associations and student groups in the region.
Maladaire
Expanded polystyrene (Ep)
e
th
A large portion of beach-litter is transported to the location where it is found.
Litter survey results from other organizations
Versoix
Read the full report from the local chapter of Surfrider Foundation.
n
so
p -ti
o er
There are two other associations that do beach-litter surveys on the lake : Surfrider Léman and Sol à tous. They do not share the data with other organizations, however the total pieces collected per survey are posted on social media.
Water treatment plants are not designed for this type of material, thus cotton swabs are released into the environment on a regular basis.
5’876 pieces or 20.9% of total.
r
ha
sc di
te
ra
m
ec
/s
Baye de Clarens
1’214 pieces or 4.34% of total.
e
on
Rh
ge
=
3
Montreux gauche
Plastic sheeting and films
Bio filters are used in the water treatment process. They arrived in two waves first from the Rhone in 2012 (round type) and then from St Prex in 2013 (square type). Identified in 41 out of 80 surveys, the Oyonne is the only location where no Bio filters were identified.
Thonnon
http://www.pelletwatch.org/
Cotton-swabs are found at all locations, the maximum is 6.75 pcs/m (Pierrier Sud). Cotton swabs are a global problem and are found on beaches all over Europe.
191 pieces or 0.01% of total.
Vidy
Identified as a transport medium of toxic chemicals in the marine environment by International Pellet Watch. GPI accumulate chemicals such as PCB, DDT and Nonylphenol.
1260 pieces or 4.5% of total.
Bio filters
Veveyse
Found at all locations, dark blue is the common color. Plastic resin pellets are the raw material for the fabrication of plastic articles. Pellets range from barrel shaped to disc shaped and measure 2 to 5mm.
Cotton swabs
Boiron
Plastic-pellets / GPI
Transport methods
Pierrier
Items in Lac Léman that are found along European shores
50 45
55
Pieces per meter of shoreline
Plastic film is found throughout the lake in various states of decomposition. The most common type found is a heavy gauge plastic similar to the sheeting used to protect objects out of doors from the elements.
International School of Geneva
The most common item found on the lake-shore. Used in the construction, manufacturing and packaging industries, EP quickly fragments into pieces 1-2mm in Shotgun wadding is found on the beach all over the globe, diameter.
November 2015 - November 2016 n=87, unts = pieces/meter of shoreline.
Ecole Polytechnique Fédérale Surfrider Lac Léman Sol à Tous MCBP2
8.44
Density weighted average (location)
6.89
8.46
6.03
50.10
Maximum density
89.31
0.68
Minimum density 90th percentile
0.02 15.81
(48.08, 55.98]
(32.28, 40.18]
(40.18, 48.08]
(24.38, 32.28]
(0.68, 8.58]
(16.48, 24.38]
Frequency of results
100
OSPAR surveys n=130, lac Léman surveys n=80
80
38
Density non weighted average
17.5
Chart 8: probability density function of ln(density) OSPAR/MCBP2
μ*= 2.3 σ*= 4.45
60
R: OS PA
-5
-3
µ=
-1
1
3
ln(density)
5
40
20 0 (55.32, 63.22] (63.22, 71.12] (71.12, 79.02] (79.02, 86.92] (86.92, 94.82]
17
# of locations
132
Chart 7: Histogram of density values OSPAR, n=130
120
(7.92, 15.82] (15.82, 23.72] (23.72, 31.62] (31.62, 39.52] (39.52, 47.42] (47.42, 55.32]
80
# of surveys
74’155
0
[0.02, 7.92]
For a complete list of survey locations and dates see annex a
27’790
# of pieces
20
Density : pieces/meter
Frequency of results
The OSPAR data can be downloaded from here:
OSPAR
40
The Z-test of sample means, greater than 5, confirms the difference between the OSPAR samples and the MCBP2 samples. This result holds true wether the natural log is used or the the geomtric mean.
, σ= 0 .911
The MCBP2 data can be downloaded from here.
MCBP2
Once the natural logarithm of the density values for both sample sets is taken and the Probability Density Function (PDF) is graphed, chart 8, the relationship between the two sample sets is more evident.
1.4 94 2:µ = 1.6 89
Key figures MCBP2/OSPAR
The recommended minimum shoreline value in OSPAR is 100m of sandy or gravel beaches. On Lac Léman there are few beaches that are 100m or greater, in order to increase the amount of surveys and variety of locations the minimum length was adjusted to the topography of the region.
Frequency of results
Chosen randomly, the OSPAR 100m survey results from those five countries represent 130 surveys from 38 different locations. The greatest concentration of surveys comes from the United Kingdom and Portugal.
Table two:
The distribution of beach-litter density values is log-normal for both sample sets (MCBP2 and OSPAR). This property is normal for many types of data, including environmental data.
2. The minimum shoreline value is 5m
μ*= 5.42 σ*= 2.49
60
BP
2015 marine litter survey results from the United Kingdom, France, Belgium, Denmark and Portugal were compared to the results from the MCBP2.
Converting OSPAR densities from values per 100m to 1m is straight forward and allows a direct comparison of the distribution of values from MCBP2. The histgrams of both distributions are positively skewed, chart 6 and 7.
MC
Like the MCBP2, OSPAR data is collected under similar conditions and by similar groups of people: volunteers actively engaged in monitoring shoreline litter and following a protocol.
80
σ=
OSPAR and MCBP2
100
(8.58, 16.48]
The MLW categorization system is more detailed than OSPAR, for example in the MLW system plastic lids are separated into three categories instead of one for OSPAR. This does not effect the total number of pieces per length of shoreline and permits a more thorough analysis of root causes and origin of beach litter debris.
Chart 6: Histogram of density values MCBP2, n=80
120
For OSPAR surveys the standard unit is 100m of shoreline because the minimum length is 100m. The variety of shoreline lengths in MCBP2 requires a smaller standard unit (to incorporate surveys of less than 100m).
1. Objects are categorized according to MLW categories
Distribution of density values :
The summary data for the two sample sets can be found in table two.
3. The standard unit is one meter of shoreline
MCBP was modified from the OSPAR protocol in three very specific ways:
0. 83 3,
Beach litter survey results from other countries
Density : pieces/meter
Density and composition:
to both MLW and OSPAR surveys. Chart 9 summarizes the results.
OSPAR and MCBP2
The OSPAR sample set was sorted by average density per location in descending order. The top sixteen locations were compared to the average density per location of MCBP2 samples. The comparison includes the converted values for the key items from chart 1 and 2 common
Like the MLW comparison, the beach litter composition of OSPAR and MCBP2 are similar. In the MCBP2 results the proportion of density attributed to key items is greater than the OSPAR results. See annex a for the list of locations and densities, how items were classified and how densities were converted.
Chart 9: average densities per location in descending order. Comparing 16 of the most densely polluted OSPAR beaches from the sample group to 16 locations from Lac Léman*. OSPAR, n= 66 surveys and 16 locations; MCBP2, n= 80 surveys and 16 locations 50
*
*
Lac Léman Polystyrene and plastic pieces Cigarette butts
*
Cotton swabs
40
*
Plastic sheeting and films Plastic caps all types
*
Discussion: The data presented is a comparison of samples taken by volunteers in six
countries in Europe. The volunteers all had a minimum of training and experience, either as part of the OSPAR program or as a member of the hammerdirt association. The notable difference between the sample sets is the absence of commercial fishing gear and other nautical equipment in the Lac Léman surveys, these items are identified regularly in the OSPAR and MLW surveys.
The density distributions are both positively skewed and log-normal.
This type of distribution is common with data that has a minimum value of zero (no negative densities), low average values and large variances. The histograms of both the OSPAR and MCBP2 sample sets display these characteristics. The distribution of values from the MCBP2 are within the range of the OSPAR data both in total density and density of key components.
The results from other groups on the lake following the OSPAR protocol produce values that are within the distribution of the MCBP2 results (and by default within the OSPAR distribution). When using the hammerdirt protocol elementary school and university students also reported values that are within the distribution of MCBP2 results.
The composition of Lac Léman trash can be characterized by the relative proportions of 16 key items. The key items from Lac Léman have a greater proportion of total density than the same items from the MLW or OSPAR surveys. According to the report published by the EPFL in 2014 there is a higher density of suspended micro-plastics in the lake when compared to the ocean. These particles likely come from the fragmentation of larger objects primarily expanded polystyrene (Styrofoam) and plastic wrapping. The findings from MCBP2 confirm both the elevated total density and the proportion of expanded polystyrene, fragmented plastic and wrappers to total density.
Shotgun cartridge Everything else
*
Conclusion: The density and composition of litter along the shores of Lake Geneva is
* 20
similar to the litter found in marine environments of Western Europe. The presence of the same items at different locations and in similar proportions (relative to total density) indicate a common origin for many of the key items found along the lake.
*
The density of suspended anthropogenic debris in Lac Léman resembles that of the ocean: areas that are severely affected by debris accumulation and areas that are less affected. However, there are no unaffected regions.
* * 10
0
*
*
*
* * * *
Skagen Strand Polhawn St Gingolph Pierrier sud Bain des dames Port, Tour-de-Peilz Arabie Crammon Beach Oyonne Sand Bay Pierrier Jubilee Beach Amoeiras Maladaire Lunderston bay Villa Barton Kilkeel North Jardin Botanique Fonte de Telha Monte Velho Vidy Le Braye Slip Osso da Baleia Felixstowe Koubou Rottingdean Baye de Montreux Robin Hoods Bay Thonnon les Bains Veveyse Baye de Clarens Boiron
Pieces of trash per meter of shoreline
30
The shift to the right of the PDF of ln(density) for the MCBP2 results (chart 8) and the greater concentration of key items when compared to the marine environment (chart 2 and 9) indicate that there is a higher probability of having an elevated density value on Lac Léman as opposed to the OSPAR sample group. The Z-test of sample means, greater than 5, suggestst that the null hypothesis can be rejected and that the density of shoreline trash on Lac Léman is elevated when compared to the OSPAR sample group. The returns from St Sulpice, Allaman and Anthy-sur-Léman (beach-litter-survey results from non-affilitaed organisations) suggest that the density in the Haut-Lac maybe lower than other regions. The initiative by Surfrider Léman and Sol à tous is welcome, the density values from those surveys are an independent voice to our data, hopefully they will continue.
Limitations of this study: The data collection is repetitive and requires a certain amount of physical effort, the categorization of objects is tedious, subjective and could be described as “déplaisante” or “unpleasant”. Litter collection happens along the lake therefore weather and seasonal changes may influence collection and sorting for example; the shore may be snow covered or waves may limit site exposure. Logistically it is not feasible to keep samples, limiting the opportunities to do recounts to evaluate categorization variances between volunteers. Improving this study: The study would benefit from a greater diversity in locations and
more regular surveys (once a week or once month). A real university partnership either in data visualization/modeling or data analysis would allow for more and varied interpretations of the data. Partnerships with civil or mechanical engineering groups could help evolve the surveys in a direction that supports product development (filtration techniques, urban hydrology, storm water catchment)
Next steps for hammerdirt: Continue to monitor and conduct surveys, over time the
combined data will open up the possibility of time series analysis. Other projects that compliment the MCBP series: 1. Development of density map of beach litter on Lac Léman 2. Construction of DIY water monitor 3. Plan MCBP3
Recommendations : There are several action plans in existence for marine environments. Initially education and outreach should be focused on educating groups and organizations with a direct stake in the health of the lake. 1. Develop a common data set for the region with a standardized protocol. Encourage groups with a shared interest to participate, for example rowing clubs, fishing clubs or elementary schools, scout troops or lifeguard groups. Invite the industrial and commercial sectors to participate. 2. Integrate the beach-litter data into environmental assessments by including beach-litter-density in the system of “Appreciation and analysis of Swiss lakes” and the “National Survey of Swiss Waterways”. The presence of solid waste was noted in the last published survey of Swiss waterways. Adding a module to the appreciation system based on observations from previous studies is a reasonable response. 3. Treat this as a regional or national problem. The effects and solutions are multiplicative ( like the standard deviation and the geometric mean of log-normal distributions), the changes or efforts of one commune would be difficult to measure. Solutions need to be implemented on the scale of the water shed, not communal or cantonal boundaries. 4. Develop a preventive communication strategy that targets the objects found in the lake. 5. Create a common funding scheme or partnership so communities in the basin have access to resources necessary to prevent aquatic litter. 6. Facilitate and simplify the marking of storm-water drains throughout the basin. Use simple measures like stencils and non toxic paint combined with art designed by students in the region. These activities go along way to raising awareness and encouraging participation. 7. Enforce existing littering and pollution laws. Fines and penalties of individuals and industries may fund clean up efforts and deter flagrant pollution tendencies.
Links to annexes and references Annexes Annex a : Converting data for this report, list of all beach litter surveys used in the report Annex b: Methods, background, Swiss law and aquatic litter, full analysis, regression results
Case Studies Chez Mme. Michelet: One resident tries to reason with local and state officials about the systematic pollution of her lakeside property. A case study based on correspondences and an evaluation of beach litter composition. The Jazz Effect: How much does the Montreux Jazz festival contribute to beach litter density and what does the city of Montreux do to prevent it.
Data All the data used for this report
This is a hammerdirt publication
Somebody needs to do this
hammerdirt association 2017 all rights reserved