dynamics [Vinogradov, 1988]. 
Monitoring of the Ecosystem Dynamics 
The Amudarya delta was covered by space photography from manned spacecraft "Soyuz-9" in 1970, from 
"Salyut-4" in 1975, from "Salyut-6" in 1980 and from "Salyut-7" in 1985 for long-term monitoring of the 
ecosystem dynamics. Thus, the Amudarya delta was surveyed through equal time intervals each 5 years. All 
space photographs were taken with photographic metric camera KATE with f= 140-210 mm on panchromatic 
films with spatial resolution near 50-80 m. Thus, technical conditions of all photographic space surveys were 
comparable. Then, natural conditions of photographic space surveys were unified also: dry weather and clear 
air of late summer season (august-september). Simultaneously a range of test sites over the Lower Amudarya 
delta was studied on the ground from 1975 during last 15 years. 
Using repeated aerial and space photos tested by field works we could monitor the ecosystem changes of the 
Lower Aanudarya delta for each 5 years. 
1960-1965. Decrease of water flow of the Amudarya river was not marked before 1965. Variations of river 
disharge was within the equilibrium state. Hydromorphic ecosystems (Hydr, HyMe, HyHa, see tabl.l) 
dominated on the delta plain. Meadow and tree-scrub ecosystems were favourable and stretched along river 
channels. 
1965-1970. Aerial surveys and space photographs from "Soyuz-9" revealed beginning of drying over delta plain. 
Although composition of ecological dominants in hydro- and mesoimorphic ecosystems is remained the 
condominants could be changed and morphometric characteristics (such as decrease of soil humidity, plant 
density, high, and fidelity and increase of soil salinity) became worse. 
1970-1975. Space photographs from "Salyut-4" made evident the desertification process. As was revealed 
on photographs the composition of ecological dominants was changed. Area of hydro- and mesomorphic 
ecosystems began reduce and area of xero- and halomesomorphic ecosystems began growth. 
1975-1980. Space photographs from "Salyut-6" indicated the critical level of desertification when they reach 
of limit admissible size near 30% of area but they had a possibility of reverse successions. Area of forest-shrub 
mesomorphic associations was chortened twice. 
1980-1985. Finally, space photographs from "Salyut-7" showed catastrophic stade of desertification. Amudarya 
river depleted and didn't fall into Aral sea. Desertification reaches 70% of the delta plain and is growing 
disaster stade. In contrary, swamp, meadow-swamp and meadow-forest (tugai) ecosystem classes drop below 
then 15% of area. 
The Ecosystem Dynamics Forecasting 
The analysis of the dynamic trends of area changes of the ecosystem classes within the Lower Amydarya delta 
reveals the ecosystem dynamics through desertification using successive space photographs 1970, 1975, 1980, 
and 1985. Comparison of areas of all ecosysytem classes with successive space photographs indicates the form 
of trends. The dynamic trends of area changes of the most ecosystems are seen to be nonlinear. The nonlinear 
trends have a curve of form: 
& $ 
Y[n]= a + b(X[i] - X[o]) + c(X[i] - X[o]) , 
where Y is the area of delta occupied by n-th ecosystem classe, X[o] is the conventional year of the beginning 
of the significant ecosystem area change, X[i] is the current year of the aerospace survey. At one case the 
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