494 
properties would be of great importance for crop 
monitoring ('CROPSAT': Bouwmans 1985). At present 
technical and economical constraints make such a 
solution rather unlikely. The data produced by the 
LANDSAT-TM scanner and the SPOT satellite does al 
ready put a serious challenge to the current proces 
sing capabilities of both satellite operators and 
users. This is notwithstanding the request dependent 
coverage of both satellites. For the time being ap 
plication of MSS-techniques in humid regions with 
intensive land use, as in the Netherlands, will main 
ly depend on airborne sensors. 
sensing. Deelrapport 4, remote sensing studiepro- 
ject Oost-Gelderland. Nota 1542. Institute for 
Land and Water Management Research, Wageningen. 
85 pp. 
Tucker, C.J. 1977. Use of near infrared/red radiance 
ratios for estimating vegetation biomass and 
physiological status. Proc. 11th int. symposium of 
remote sensing of environment 1:493-494. 
REFERENCES 
Badhwar, G.D., J.G. Carnes & W.W. Austin 1982. Use of 
LANDSAT-derived temporal profiles for corn - soy 
bean feature extraction and classification. Remote 
Sens. Environ. 12:57-79. 
Batista, G.T., H.M. Hixson & M.E. Bauer 1985. LAND- 
SAT-MSS crop classification performance as a func 
tion of scene characteristics. Int. J. Remote 
Sensing 6,9:1521-1533. 
Belmans, C., J.G. Wesseling & R.A. Feddes 1983. Simu 
lation model of the water balance of a cropped soil: 
SWATRE. J. Hydro1. 63:271-286. Techn. Bull, ns 21. 
Institute for Land and Water Management Research 
(ICW), Wageningen. 
Bouwmans, J.M.M. 1985. Practical application of remote 
sensing techniques in water management problems, 
state of the art. Proc. Intern, workshop on hydro- 
logic applications of space technology. Cocoa 
Beach, Florida, August 18-23 (in press). 
Crist, E. & W. Malila 1981. A technique for automatic 
labeling of LANDSAT agricultural scene elements by 
analysis of temporal-spectral patterns. Proc. 15th 
intern, symposium on remote sensing of environment. 
Ann Arbor, Michigan:1227-1236. 
Feddes, R.A., P.J. Kowalik & H. Zaradny 1978. Simula 
tion of field water use and crop yield. Simulation 
Monographs. PUDOC, Wageningen. 189 pp. 
Jackson, R.D., R.J. Reginato & S.B. Idso 1977. Wheat 
canopy temperature: a practical tool for evaluating 
water requirements. Water Res. Res. 13:651-656. 
Kok, A. 1984. Studie naar de effecten van grondverbe- 
tering in de veenkoloniën met remote sensing. Nota 
1532. Institute for Land and Water Management Re 
search (ICW), Wageningen. 50 pp. 
Laat, P.J.M. de & R.H.C.M. Awater 1978. Groundwater 
flow and évapotranspiration; a simulation model. 
Part 1. Theory. Basisrapport Commissie Bestudering 
Waterhuishouding Gelderland. Provinciale Waterstaat 
van Gelderland, Arnhem. 64 pp. 
Nieuwenhuis, G.J.A., E.H. Smidt & H.A.M. Thunnissen 
1985. Estimation of regional évapotranspiration of 
arable crops from thermal infrared images. Int. J. 
Remote Sensing 6,8:1319-1334. 
Seguin, B. & B. Itier 1983. Using midday surface tem 
perature to estimate daily evaporation from satel 
lite thermal IR data. Int. J. Remote Sensing 4,2: 
371-383. 
Soer, G.J.R. 1977. The TERGRA model - a mathematical 
model for the simulation of the daily behaviour of 
crop surface temperature and actual évapotranspira 
tion. Nota 1014. Institute for Land and Water 
Management Research (ICW), Wageningen. 44 pp. 
Spaans, J.H. 1985. Studie naar de invloed van leemla- 
gen in de ondergrond op de vochtvoorziening van 
gras en mais in een gebied nabij Rucphen (West- 
Brabant); de toepassing van remote sensing technie- 
ken en hydrologische modelberekeningen. Nota 1696. 
Institute for Land and Water Management Research, 
Wageningen. 57 pp. 
Thunnissen, H.A.M. 1984a. Eenvoudige méthode voor de 
bepaling van de régionale gewasverdamping. Deelrap 
port 6, remote sensing studieproject Oost-Gelder- 
land. Nota 1580. Institute for land and Water 
Management Research, Wageningen. 39 pp. 
Thunnissen, H.A.M. 1984b. Hydrologisch onderzoek: 
toepassing van hydrologische modellen en remote