Locusts — Inventory (1990/98)

Observations from the 1990 investigation were recorded in a 4th-dimension database, while Wolf’s investigation was tabulated (Excel). Walter’s examined areas were plotted on overview plans 1:5'000. Areas with protected species (1 to 3 species combinations) were excreted as actual inventory areas, while the other areas were grouped only in one study perimeter and were not further differentiated. For Wolf, on the other hand, only the respective perimeters were recorded by the shape of natural inventory surfaces or by the indication of circular radii. Walter’s surfaces were digitised in the GIS as readable from very poor black and white overview plans copies. On the one hand, the surfaces of the Wolf investigation were digitised as inventory surfaces and on the other hand were obtained by the automatic generation of circular surfaces. The attributes of the two entries were merged into one schema and exported as a new GIS point record. Subsequently, the GIS point dataset was linked to the surfaces as far as possible. As linking criteria, the spatial superposition and/or comparable attribute values of close objects were taken into account. The locust inventory therefore consists of two data sets and a correlation table between areas and species observation points: • Inventory Areas • Observation points in the inventory areas Municipalities Investigation Walter: Altikon, Bassersdorf, Benken, Boppelsen, Bülach, Bubikon, Dietlikon, Eglisau, Elsau, Embrach, Glattfelden, Gossau, Hausen a.A., Hinwil, Hombrechtikon, Humlikon, Hüntwangen, Illnau-Effretikon, Kleinandelfingen, Knonau, Laufen-Uhwiesen, Maur, Mönchaltorf, Oberglatt, Otelfingen, Rümlang, Schönenberg, Sternenberg, Uster, Volketswil, Wasterkingen, Weiach, Wetzikon, Will, Wila Communities Investigation Wolf: Bubikon, Dachsen, Dürnten, Fällanden, Flaach, Greifensee, Hombrechtikon (without Lützelsee and surroundings), Illnau-Effretikon, Kleinandelfingen, Lindau, Marthalen, Ossingen, Rheinau, Schwerzenbach, Truttikon