How do you calculate the area of a lake or region ?

The formula is: length (m) width (m) number of acres.

The traditional formula for calculating the number of acres of land is: 1 mu = 60 square feet = 6000 square feet = square meters.

square meters are changed to acres, and the calculation formula is "add half and move three left". 1 square meter mu, such as 128 square meters is equal to how many acresThe calculation method is to add 128 to half of 128: 128 64 192, and then shift the decimal point to the left by 3 places, that is, the number of acres is.

Mu for square meters, the calculation formula is "divide by three, double the right move three". If you want to calculate how many square meters per mu is equal to, double it as, and then shift the decimal point to the right by 3 places, that is, the number of square meters is 16400.

The formula is: length (m) width (m) number of acres.

For example, the land area of 200 meters long and 150 meters wide is:

200 (m) 150 (m) sq m mu).

Length (m) Width (m) 667 = number of acres.

For example, if a piece of land is 60 meters long and 40 meters wide, the formula is 60x40 667 and the number calculated is the number of acres.

Grid method, surveying and mapping maps, dividing them into 1cm grids, greater than or equal to half of the grid is counted as one, less than half of the grid is rounded, and the number of grids is multiplied by the scale ratio.

Get a picture of the ** directly above the lake, and then use the lattice method to calculate the area on the **, and then multiply it by the corresponding proportion.

1. Use the latest satellite image data to circle the area. Google Earth's imagery is updated faster. This method is simple, but the real-time performance depends on the time when the image is taken.

2. Use GPS recorder, it is really not good to use mobile phone GPS, run, ride, drive, and circle along the lake, and use the recorded trajectory circle to calculate the area.

3. UAV aerial photography generates high-resolution fast puzzles with GPS coordinates, which are calculated by GIS or CAD loading, accurate and real-time.

4. Differential GPS, RTK on-site collection of lake edges, the most troublesome, but the most accurate.

The general lake area requirements are not so precise, and the first two methods will do.

Depending on how big your lake is, if you have a large area, use GPS to measure the inflection points of the lake, import the CAD exhibition points, and automatically calculate the plane area.

1. More than 10,000 square kilometers.

The Caspian Sea is 386,400 square kilometers, the Great Lakes are 245,200 square kilometers (including 82,414 square kilometers of Lake Superior), Lake Victoria is 69,400 square kilometers, Lake Baikal is 31,500 square kilometers, Lake Big Bear is 31,000 square kilometers, Lake Danu is 28,600 square kilometers, Lake Winnipeg is 24,400 square kilometers, Lake Balkhash is 18,000 square kilometers, Lake Ladoga is 18,000 square kilometers, and 2,000-9,999 square kilometers.

Lake Titicaca is 8,300 square kilometers, North Aier Lake is 8,200 square kilometers, Issyk-Kul Lake is 6,332 square kilometers, Wienern Lake is 5,650 square kilometers, Jaisangbo is 5,500 square kilometers, Qinghai Lake is 4,400 square kilometers, Saima Lake is 4,400 square kilometers, Chude Lake is 3,550 square kilometers, Great Salt Lake is 3,525 square kilometers, Poyang Lake is 3,150 square kilometers, Alahu Lake is 2,650 square kilometers, Dongting Lake is square kilometers, Taihu Lake is 2,445 square kilometers, and Hongze Lake is 2,069 square kilometers, Chaohu Lake square kilometers.

3. 1000-1999 square kilometers.

Namtso is 1,961 square kilometers of the town, Loch Ness is 1,800 square kilometers, Bosten Lake is 1,646 square kilometers, and Weishan Lake is 1,266 square kilometers.

4. 100-999 square kilometers.

Lake Geneva is 580 square kilometers, Lake Constance is 536 square kilometers, Lake Selim is 458 square kilometers, Dianchi Lake is 330 square kilometers, Plitvice Lake is 294 square kilometers, Erhai Lake is 251 square kilometers, Miyun Reservoir is square kilometers, and Lake Como is 146 square kilometers.

5. 1-99 square kilometers.

Kanas Lake square kilometers, Wuhan East Lake 33 square kilometers, Changbai Mountain Tianchi square kilometers, Hallstatt Lake square kilometers, Hangzhou West Lake square kilometers, Kings Lake square kilometers, Tianshan Tianchi square kilometers, Buhong Lu Ryder Lake square kilometers.

Saturday, June 25, 2022 The weather is fine.

This question is computationally intensive.

The sine and cosine theorems are mainly used.

The area of the upper and lower triangles is governed by the sinusoidal theorem.

s=1/2absin∠c

Find the length of two dashed lines using the cosine theorem of the upper and lower triangles.

c²=a²+b²-abcos∠c

Then, when finding the area of the middle triangle, first use the cosine theorem to find one angle of the triangle.

Then use the sinusoidal theorem to find the area.

Although the lake is irregular, it can be divided according to the knowledge we learned in junior high school, and the irregular lake surface can be divided into regular lake surface and calculated, and the area of the lake surface can be roughly calculated.

Using the cosine theorem, it is easy to find the length of each side and then the area.

Solve (The area of the lake is the sum of the three triangles).

This is a bit too difficult, you can search for this question in the next little ape search question or a question bank or something, take a picture and upload it. If it really doesn't work, you can ask the math teacher, because this diagram should be incomplete, and he has parts that are all out of the graph.

The lake area refers to the area within the boundaries of the lake. When the water level of the lake rises, the lake area increases. When the water level decreases, the lake area decreases, and the two are a function of the relationship, and the general water level-area relationship curve represents this characteristic. In order to calculate the volume of the lake, it is necessary to know the area enclosed by each depth contour, i.e., the area of the water surface at each depth at different isobaths.

The method of accurately measuring the area of the lake is usually the plotter method. If there are islands in the lake, the total area of the lake and the area of each island must be measured, and the difference between the two is the lake area. In square kilometers.