parameters.bcsb: Spring barley aphid biocontrol model parameter values

In yclough/ecodeal: Functions for economic-ecological analyses of agricultural landscapes

Description

Parameter values as used in the model. There are three stages: colonizing, growing ground-living and growing flying. PRED_PAR contains the predation rate during aphid colonization (1st column), predator units (columns 2-4), predator initial populations (columns 5-7), predator populations as influenced by the land-use (columns 8:10), coefficients a0 (columns 11-13), b (columns 14-16), c (columns 17-19). OTHER_PAR contains Wo, N00, m2, m3, f, maloss (all in their individual columns). The number -99 means that the landscape does not influence population size during that stage. The predator groups are, in order of appearence in the data tables Wolfspiders,Sheet-web spiders, Large ground beetles,Carabidae, large, small ground beetles,Rove beetles, Adult lady beetles, Juvenile lady beetles, Lacewing larvae,Syrphid larvae) p0 are the attack rates calculated from U predatory units, and the othe parameters corresponding to 1 U; p Attack rate accounting for the U of each predator group

Usage

parameters.bcsb

Format

A list with dataframes (or lists) containing:

PRED_PAR

Predator parameters, Predation rate during aphid colonization (see above)

pw

Predation rate during aphid colonization, calculated from mortality m=(N00-N0)/N00 in <c3><96>stman et al. 2003

U

Predator units of the enemies during the different stages

P

Baseline predator densities during the different stages

LU

relevant land-use for the different groups and periods (1=PNAC135; 2=PNAC500; 3=PNAC1500; 4=PGL500)

a0

Used in the calculation of P0 (Phat in Jonsson et al) and Gompertz function coefficient a (Jonsson et al, eqn. 9)

b

Gompertz function coefficient (Jonsson et al, eqn. 9)

c

Gompertz function coefficient (Jonsson et al, eqn. 9)

OTHER_PAR

Other parameters (see above)

W0

N0 from v<c3><a4>xtskyddscentralens barley fields (=3.6)

N00

N00 is the size of the colonizing population, before any predation. (=3.49)

m2

Mortality in the second phase (=0.027), estimated from the reduction in r

m3

Mortality in the third phase (=0.054), estimated from the reduction in r

f

Fecundity (per day), 1.9/7=.2714 from Dean (1974)

T

Duration of the growth period, in days (=14)

th

Threshold to apply insecticide, in number of aphids per tillar (=5)

maloss

Yield loss due to machinery driving over the crop when spraying in percent (=0.002)

time_limit

Time after which it is not worth to spray, in days (=10)

References

Jonsson, M., Bommarco, R., Ekbom, B., Smith, H. G., Bengtsson, J., Caballero-Lopez, B., Winqvist, C. and Olsson, O. (2014), Ecological production functions for biological control services in agricultural landscapes. Methods Ecol Evol, 5: 243-252. http://dx.doi.org/10.1111/2041-210X.12149 <c3><96>stman, <c3><96>., Ekbom, B., & Bengtsson, J. (2003). Yield increase attributable to aphid predation by ground-living polyphagous natural enemies in spring barley in Sweden. Ecological Economics, 45(1), 149-158. https://doi.org/10.1016/S0921-8009(03)00007-7 Dean, G. J. (1974). Effect of temperature on the cereal aphids Metopolophium dirhodum (Wlk.), Rhopalosiphum padi (L.) and Macrosiphum avenae (F.)(Hem., Aphididae). Bulletin of Entomological Research, 63(3), 401-409. https://doi.org/10.1017/S0007485300040888

yclough/ecodeal documentation built on May 14, 2019, 2:01 a.m.