Examina ion o low, sedimen and
phospho us ela ionships using moni o ed
s o m e en da a om a mul iscale esea ch
pla o m
Yusheng Zhang, S e e G ange , Tegan Da ch, Louise Olde and Adie Collins
Ag icul u e and he En i onmen
Aa hus, Denma k, 3-6 June 2025
The challenge
En i onmen al Imp o emen
Plan: 40% educ ion in sedimen
and nu ien loss om ag icul u al
land by 2038 compa ed wi h a
baseline in 2018
Sou ce: h ps://doi.o g/10.1007/s13593-025-01015-4
BBSRC na ional capabili y
•No h Wyke Fa m Pla o m (NWFP): 15
hyd ologically-isola ed ield scale
ca chmen s; 4 ca chmen s we e
a ge ed.
•Uppe Ri e Taw Obse a o y (URTO): 3
nes ed ca chmen s (Uppe Ra combe,
Lowe Ra combe and Pecke s o d) wi h
con as ing land uses
•High esolu ion and con inuous
moni o ing and eco ding o ain all,
low a es, sedimen and nu ien s
(ni ogen and phospho us), e c.
•Focus on selec ed s o m e en s whe e
lab da a o sedimen and phospho us
a e a ailable o physical wa e
samples
S o m sampling and labo a o y analyses
•Sampling pe iod: No 2018 o Feb
2021.
•Numbe o e en s pe ca chmen :7 -
10
•NWFP: Flow-based sampling; 7 – 8
samples pe e en ; co e bo h alling
and ising limbs.
•URTO: Time-based sampling; 24 – 48
samples pe e en ; co e whole
hyd og aph.
•All samples we e analysed o
suspend solids (SS) and o al
phospho us (TP) concen a ions
(sodium hyd oxide usion)
Smi h, B.F.L., Bain, D.C. (1982). A sodium hyd oxide usion me hod o he de e mina ion
o o al phospha e in soils. Communica ions in Soil Science and Plan Analysis 13(3), 185-
190. h ps://doi.o g/10.1080/00103628209367257
Si es expe ience designed a able con e sion
and ex eme wea he condi ions.
Maximum concen a ions in he s o m e en s
Ca chmen
a ea
(km2)
Land
uses
Sedimen
conc.
mg/l
TP
conc.
µg/l
NWFP
Ca chmen 2
0.0673
g ass and hen
con e ed o a able
in Sep 2019
981
1413
Ca chmen 3
0.0684
g ass and hen
con e ed o a able
in Sep 2019
1423
2905
Ca chmen 5
0.0673
imp o ed g ass
206 699
Ca chmen 8
0.0733
pe manen g ass
317
1073
UTRO
Uppe
1.7
g ass
172 282
Lowe
4.4
majo a ea o a able
765 852
Pecke s o d
41.4
mixed
424 546
Da a p ocessing and analysis
•Phospho us con en o sedimen :
o al P concen a ion di ided by
sedimen concen a ion. Mean
alues o each e en we e
es ima ed
•Sedimen and phospho us
ela ionship: simple linea
eg ession o es ima e slopes;
co ela ion analysis o assess he
s eng h o he ela ionship.
•S a is ical es s o compa e
di e en land uses.
•Load es ima es a UTRO:
mul iplica ion o low a es and
concen a ions.
Example e en da a om Pecke s o d -
URTO
Flow a es and SS concen a ions on NWFP: land use change
Sou ce:
h ps://doi.o g/10.1016/
j.agee.2025.109713
SS and TP concen a ions on UTRO: d y yea s we yea
SS and TP concen a ions on NWFP
TP con en o opsoil (down o 10 cm) was
es ima ed o be a ound 0.09 o 0.14% based
on soil su ey unde aken in 2016.
