L9 Chemical Pollution Part 2 pesticides/food web/monitoring Flashcards
general overview
- Biomagnification/Bioaccumulation
- Pesticide Need and Toxic spills?
- DDT, pesticide problem + Chlorpyrifos
- Biomonitoring (4)
- what biomonoitors used?
- Compensatory response / Resilience and Recovery
- Current + Future work
Biomag Bipacum
difference
examples that bioMAG (6)
bioac example from fisheries
Biomagnification- increases UP food chain, by eating multiple prey – ie Saithe in fisheries practical
Bioaccumu - indivudal level
dioxins, organochloride ,pesticides DDT , radionuclides , heavy metals TBT antifouling paint
PCBS and Dioxins - linked iwth birt hdefects
Cod liver oil - can be high in PCBs and dioxins
bioaccumulation is contamination levels over tme build up in same organism (ie sandeel, sole – spawning and nesting ground – sandeel burrows and hibernates in sedimentary soil)
what are linked with birth defects
PCBs and dioxins
Wh ydo we have pesticides ?
Trends of use?
global need to feed 7bn humans
boost yield
remove enermies 9pests /pathogens) to boost indirectly
US $ imports of pestciicde import and production increase betweem 1940-2000
pesticide increase in imports and production between
1940 and 2000
need to feed
7 billion
What can toxic spills tel us? (30
a) can devastat ecosystems
b) Yet much unknown about effects
c) fish kills provide early WARNING
DDT main points (4)
Rachel Carson - book
Influence on Policy + sucess?
Human Impact
Evidence (3)
DDT Rachel Crason
what does ddt do?
why no song?
Silent Spring
• DDT causes thinning of bird eggs as it bioaccumulates and magnifies through food webs – birds dying so no song
DDT - public and policy ? Effective?
increASE BETWEEN
recovery of what (us + uk)
DDT was banned
looking at historical data and occupied territories since 1980-2005 can see a clear increase
Organochlorine impacts and subsequent recovery in American peregrine falcons
DDT - human impact
where can we see residues?
residue levels in human adipose tissue
in human milk
Pesticide - human impact
USA
UK
JAPAN
- USA can be seen between 1970-1983 DDT declining and low Dieldrin an HCH (BCH)
- UK 1963-1983 DDE dlightly decreseDDT has decreased a lot but HCH and Dieldrin slightly higher levels than us but also stayed the same (note scale shows less than US overall)
- Japan 1976-1985 Can see diedrin stopped in 1977 and can see more PCB and HCH although this is slightly declining (note- scale shows more of each overall) for example staggering 45 mg per KG of DDT in 1976 (v high in com;arison to US and UK)
Pesticide human impact what chemicals?
DDT
Dieldrin
HCH
PCB
Pesticide evidence (3)
farmland bird declines
pollinators
agric footrpint (pesticide economy)
pesticide evidence 1 detail (bird)
birds (6)
total lost?
farmland bird decline
1980-2009
• Falling population amongs 1)starling 2)Tree sparrow 3)Linnet 4)Whinchat 5)Yellow wagtail 6) turtle dove
• Overall PECBMS source shows since 1980 297 million birds have been lost
Bird spp falling pops (6)
)starling 2)Tree sparrow 3)Linnet 4)Whinchat 5)Yellow wagtail 6) turtle dove
pesticide evidence 2 9pollinators)
Many species pollinate our crops for free but for how much longer?
Honeybees are disappearing from much of Europe – pestcides have been implicated in recent studies
link to handpol
linkt to pear problem
pesticicde evidence 3 - global pesticide economy
implications?
trends since 1960?
• implicaions for the lower trophic levels in the world’s food webs
• Billions of USD
Since 1960 can see huge increase in 1)herbicides 2)insecticides 3)fungicides 4)others
Pesticide problem (clue- (3) trade off)
what approach is important?
services?
rely on what ?
network based approached to studying ecosystem SERVICE
there are trade offs with agrochemical base food production
cultural/provisioning/ supporting nad rgeulating services rely on
plants
algae
detitirs
Invertebrates, Vertebrates and Apex predators complex effects on networks in diagram
Pesticide problem -
b) what do they do to food webs? who do they knock out?
often knockout the CORE of freshwater food webs
knocks out abundant taxa
What is another organophosphate and what does it target?
Chlorpyrifos
common urban organophosphate
leatherjackets - these destroy crops and lawns
Biomonitoring (overview)
- problem (kennett)
- Riverfly partnership
- “Action for the river Kennet”
- tracking
biomonitoring 1. what is the problem?
new approach?
traditional ecotoxicology provides tight control of stressors BUT lacks realism and ignores food web effects
need a NOVEL
GENE to ECOSYSTEM biomonitoring process
example = 2016 - new integrative approach
biomonitoring 2
National citizen science biomonitoring scheme example?
what is it?
what do they work together to do (4) QCUD
Riverfly partnership
network of nearly 100 partner organisations (ie conservationists / scientists /managers etc) working togteher to
1) protect the water quality of our rivers
2) further uderstanding of riveerfly populations
3) actively conserve riverfly habitats
4) compile a riverflies monitoring database - with online recording
biomonitoring 3 regional citizen science biomonitoring scheme example? why is this important? moto? event? Importance- ban?
“Action for the river kennet”
one of most important chalk streams and 45 miles is largest tributary to River Thames in summermoths (contributes up to alf its flow)
“think globally, act locally”
biomonitoring ecosystem responses to a catastrophic petsicoide spill in a Uk river in 2013 – 15km of invertebrate life wiped out
Implications: River Kennet pesticide pollution called prompts for ban (BBC News)
Note- even small quantities can be lethal – a few tablespoons of Chloripyrifos caused this ecological catastrophe- Yet you can buy it easily on Amazon
what was the pesticide in the 20133 spill in river Kennet that led to a ban?
Chloripyrifos
Biomonitoring 4. Tracking
what is it and how can it be done?
track IMPACT and RECOVERY to quantify multilevel resilience ie 3 control sizes and 3 impact sites look ober LT (again insecticides knock out core of the food web)
- what Biomonitors can be used?
what do riverfly monitors (ARK)?
Riverfly Monitors (ARK) show invertebrate numbers decline more than 100 fold .. but (partial) recovery within a few months
- How can we collect biomonitoring data /what can we use?
3 examples
note - match to what you want to sample
Stone scrapes - algal community
Hess sampler - ivertebrates
Electropfishing bterrn stop nets : fish
- Biomonitoring spp
c)what happend adter huge pesticicde influx
_days later?
population of _ explodes?
28 days later zombie apocaplypse
explosion of flatworms feeding on millions of carcasses
- Biomonitoring spp
d) where were the initial impacts felt ?
e) what does the reference food web show
f) what is the response of the food web ? (3)
genes to ecosystem level imapcts
dominance by GAMMARUS shrimps - bodymass baundance plots show this spp dominates
food web response
1-loss of op down effects
2.increase in diatom cell sized (grazers stripped out of web)
3keystone spp wiped out (nodes lost from network)
What was the dominantspecies according to the refernce food web in the kennet river?
Gamma rus shrimps
- Compensatory Response
- structure + condequence
- gene response
community shifts towards dominance by small taxa as the large keystone spp are lost
microbrial processes dominate detrital processing in absence of large detritivores
Process: litter breakdown thus decreases
Abundance of microbrial functional genes associated with
a) processing pesticide (direct effect) and
b) with decomposting animal carcasses (indirect effect) increase
genes associated with — increase? (2)
processing pesticide (direct effect)
decomposting animal carcasses (indirect effect) increase
which genes?
Direct= oph Indirect = amoA
Resilience and recovery
after the 2013 pesticide spills?
a) case study : monitoring example and findings?
clue (again basically structural and genes)
but what is a positive?
what was the effect pf losing herviourous consumers from green pathways?
Responses were monitored from July 2013 pesticide spill – 2 months later (sep2013), 8 months later,(march 2014) 14 months later (sep 2014) and 20 months later (March 2015)
etritivorous consumers from “brown pathways” and keystone spp that were previously dominate (ie Gammarus shrimps lost
reduced decomposition rates of leaf litter due to loss of detritivores
BUT recovery within 1 yr
Order of magnitude increase in the size of diatoms when comparing impacted to reference populations in logabundance plots – why? Herbivores such as mayflies are LOST so what happens? Algal blooms
were algal blooms in repsonse to the pestcicde spoll in 2013 from eutrophication?
NO
they were due to
loss of herbicvores and thus it was NOT eutrophication due t onutrients
Recovery? Yes saw recovery after 1 year – when looking at chlorphyll concentration and comparing reference to impacted.
Resilience and reocvery ?
b) buffering?+ connectednetworks?
In highly connected networks pertubations can spread and also dissipate very rapidly
Alterantive feeding pathways can buffer stressor impacts
What is the current work being done?
gaps
new dimensions
work is being done to fill the remaining grey areas to understand th shape of resilience
emerging picture is trackingresilience in the foodweb through SPACE and TIME
Ie- loss and recovery of a super abundant species – Woodward et al Unpublished
Looking at differ sites (control and impact – over time0 Woodward et al unpublished
Current / future work?
-genetics
-
Network based approaches , eDNA and ecoinformatics promise novel means of comping with complec indirect effects that lead to “ecological suprises”
What would this genetics / sample approach include?
Routine biomonitoring data AND Environmental sample (soil,water, gt contents) generate taxon list using DNA analusis NGS
BOTH feed into
Infer network links ie from interactions database or predictive models
derive network metrics /model stability/robustness , explore food web sensitivity to environmental driver
Detail on integrating DNA?
1) Dna is extracted from bulk Benthic samples (not just free eDNA in the water)
2( then sequenced) using metabracoding –
Ie dissolve in ethanol then sieve arthropod bulk and sieve through 1mm sieve
=clean macrofauna bulk
0.45um sieve and ludox flotation = clean meiofauna bulk
Silwood future wok?
question
Trialing what?
how can we get info? (clue - Celldex experiment)
Prospects for the future can we combine informatics, DNA & network approaches to design
Next Generation Biomonitoring tools to detect multiple stressors across the globe?
trialling new molecular & bacterial “biosensors” as early warning systems and measuring ecosystem impacts of stressors at Imperial’s Silwood Park campus
Note: The power of crowdsourcing a new global bioassay of ecosystem functioning the CELLDEX experiment (in prep)
Kennet as an example for the future- why?
2 main things
- Dna techniques detected strong pesticide responses rapidly from a TINY number of smaples from the Kennet
- NMDS total beta diversity ordinations for Athropoda , Insecta and Cristacea based on presence / absence community matrices by read mapping against de novo generated OTUs at 3% and 10% for the bc-3’ and bc-5’ gene fragments
kennet mapping against?
Insecta and Cristacea based on presence / absence community matrices by read mapping against de novo generated OTUs
at 3% and 10%
for the bc-3’ and bc-5’ gene fragments
