러시아 최대의 곡창지대(Saratov Oblast)

사진을 클릭해서 보세요, 이 사진은 좀 작습니다. 누르시면 커집니다.

A지역이 Saratov Oblast 입니다.
볼가강 하류에 위치한 이 지역이 러시아 농업생산의 40%를 책임지고 있습니다.
볼가강 유역에서는 가장 큰 곡창지대이기도 하고요.

이 지역은 그루갈이를 하는데 봄과 여름사이에 작물의 종류가 변하게 됩니다.
제일위 사진중에서
위의 두개는 2002년 3월 31일 촬영한 것이고
아래 두개는 2002년 7월 18일 촬영한 것입니다.

그냥 사진만 보면 왼쪽의 두개는 "뭐야 이거! 전체적으론 누런색인데 가끔 녹색이 있고..별 차이도 없는걸"
하시겠지만, 이상하게도 오른쪽의 두개 사진은 많이 다르지요. 하나는 초록색끼가 도는데, 하나는 핑크빛이...
뭔가 삘이 오긴하는데, 뭘까 뭘까 뭘까........ 하실겁니다.

예를 들어 전봇대를 위성에서 내려다 본다고하면 전봇대 지름만한 원밖에 안보이겠지요?
하지만 60도 정도의 각도로 내려다 본다면 내 눈에는 전봇대 단면도 모양의 원이 아니라, 길죽한 직사각형일 겁니다.
보이는 모양이 전혀 달라지는 것이지요.

위성사진도 그냥 지상위에서, ray의 종류만 바꿔서 쏴대는 것이 아니라
보는 각도도 달리하니, 저런 분석이 가능해지는 것이군요.

우즈베키스탄의 곡창지대 Jizzax자료도 함께 보시지요

http://geowiki.tistory.com/entry/우즈베키스탄-곡창지대-Jizzax-Province-in-eastern-Uzbekistan

1. red band data from MISR's 60-degree backward - red
2. nadir - green
3. 60-degree forward-viewing - blue
본문에 나오는 내용인데, 미리 이 세가지를 유념하고 보시면 더 유익하시라 생각됩니다.

Russia's Saratov Oblast (province) is located in the southeastern portion of the East-European plain, in the Lower Volga River Valley. Southern Russia produces roughly 40 percent of the country's total agricultural output, and Saratov Oblast is the largest producer of grain in the Volga region. Vegetation changes in the province's agricultural lands between spring and summer are apparent in these images acquired on May 31 and July 18, 2002 (upper and lower image panels, respectively) by the Multi-angle Imaging SpectroRadiometer (MISR).

 

The left-hand panels are natural color views acquired by MISR's vertical-viewing (nadir) camera. Less vegetation and more earth tones (indicative of bare soils) are apparent in the summer image (lower left). Farmers in the region utilize staggered sowing to help stabilize yields, and a number of different stages of crop maturity can be observed. The main crop is spring wheat, cultivated under non-irrigated conditions. A short growing season and relatively low and variable rainfall are the major limitations to production. Saratov city is apparent as the light gray pixels on the left (west) bank of the Volga River. Riparian vegetation along the Volga exhibits dark green hues, with some new growth appearing in summer.

 

The right-hand panels are multi-angle composites created with red band data from MISR's 60-degree backward, nadir and 60-degree forward-viewing cameras displayed as red, green and blue respectively. In these images, color variations serve as a proxy for changes in angular reflectance, and the spring and summer views were processed identically to preserve relative variations in brightness between the two dates. Urban areas and vegetation along the Volga banks look similar in the two seasonal multi-angle composites. The agricultural areas, on the other hand, look strikingly different. This can be attributed to differences in brightness and texture between bare soil and vegetated land. The chestnut-colored soils in this region are brighter in MISR's red band than the vegetation. Because plants have vertical structure, the oblique cameras observe a greater proportion of vegetation relative to the nadir camera, which sees more soil. In spring, therefore, the scene is brightest in the vertical view and thus appears with an overall greenish hue. In summer, the soil characteristics play a greater role in governing the appearance of the scene, and the angular reflectance is now brighter at the oblique view angles (displayed as red and blue), thus imparting a pink color to much of the farmland and a purple color to areas along the banks of several narrow rivers. The unusual appearance of the clouds is due to geometric parallax which splits the imagery into spatially separated components as a consequence of their elevation above the surface.

 

The Multi-angle Imaging SpectroRadiometer observes the daylit Earth continuously from pole to pole, and views almost the entire globe every 9 days. These images are a portion of the data acquired during Terra orbits 13033 and 13732, and cover an area of about 173 kilometers x 171 kilometers. They utilize data from blocks 49 to 50 within World Reference System-2 path 170.

<From : NASA>