In the Mapbiomas Water dataset, we found 656748 water masses classified as “2 - artificial water body (anthropic dams)”.
In the Solvik dataset, we found 1150123 water masses mapped in Brazil.
The size of these bodies of water ranged from 0.074 to 7076.765 hectares in the Mapbiomas dataset. The total area is estimated at 1369764.42 hectares.
In the Solvik dataset, they ranged from 0.008 to 387.736 hectares. The total area is estimated at 704804.14 hectares.
Below is the distribution of size of all of these water masses:
A closer look at the impoundments below 5ha in area:
And below is the distribution of size and number, according to size classes.
In Google Earth Engine, we transformed the water areas into vectors, and drew polygons containing the water area, plus a buffer area of 200 meters. Then, we analyzed the profile of land use in these areas using the Mapbiomas land use data collection 8, as well as the Mapbiomas Pasture, Mining and Irrigation products as well.
Below shows the total sum of areas in these buffer areas, according to the land use type.
Below is the distribution of the percentage of the buffer area covered by each land cover class. The histograms below show further a dominance of pasture in the vicinity of the impoundments.
Considering that the buffer areas include the water mass area, the assumption was that every water mass polygon would contain at least one pixel of water area. That turned out to not be the case. Out of the 656748 Mapbiomas and 1150123 Solvik areas, only 274898 and 274898 have some water area contained in it, respectively.
Not all mapped impoundment areas have pasture area detected in the vicinity: Out of the 656748 Mapbiomas and 1150123 Solvik areas, only 519724 and 941006 have some pasture area in their vicinities, respectively.
There are many criteria to classify what we consider to be more likely a cattle impoundment, within the ones mapped in these two datasets. Below is the estimation of cattle impoundment area per state, considering different criteria.
| state | source | total | criteria1 | criteria2 | criteria22 | criteria3 | criteria4 | criteria44 |
|---|---|---|---|---|---|---|---|---|
| RS | Mapbiomas_water | 328665 | 309233 | 174613 | 174608 | 142549 | 126072 | 126068 |
| CE | Mapbiomas_water | 105206 | 98928 | 96700 | 96675 | 59596 | 37442 | 37429 |
| GO | Mapbiomas_water | 89283 | 85972 | 76857 | 76823 | 65718 | 62842 | 62723 |
| MG | Mapbiomas_water | 81046 | 78130 | 68080 | 67951 | 61152 | 55254 | 54865 |
| MT | Mapbiomas_water | 81031 | 77638 | 69139 | 69026 | 62191 | 57758 | 57588 |
| PA | Mapbiomas_water | 75570 | 66520 | 52488 | 52349 | 44350 | 41746 | 41397 |
| MA | Mapbiomas_water | 68667 | 54109 | 53361 | 53306 | 42624 | 27721 | 27460 |
| BA | Mapbiomas_water | 67248 | 63088 | 60169 | 59846 | 53428 | 37531 | 37003 |
| SP | Mapbiomas_water | 65849 | 49006 | 45968 | 45818 | 29490 | 28585 | 28420 |
| RO | Mapbiomas_water | 49550 | 48139 | 45580 | 45497 | 42564 | 38339 | 38136 |
| MS | Mapbiomas_water | 42623 | 36967 | 36617 | 36561 | 29926 | 29066 | 28915 |
| RN | Mapbiomas_water | 39715 | 37577 | 37574 | 37365 | 33339 | 20371 | 20111 |
| AM | Mapbiomas_water | 38486 | 23143 | 22838 | 22770 | 14455 | 13444 | 13288 |
| SC | Mapbiomas_water | 31390 | 27084 | 24837 | 24829 | 15654 | 15315 | 15247 |
| PI | Mapbiomas_water | 30100 | 28207 | 28158 | 28052 | 20367 | 13265 | 13182 |
| TO | Mapbiomas_water | 29394 | 28548 | 25414 | 25409 | 23005 | 22298 | 22264 |
| PR | Mapbiomas_water | 28978 | 19930 | 19169 | 19068 | 9081 | 8402 | 8329 |
| PB | Mapbiomas_water | 27353 | 26088 | 26065 | 25995 | 20054 | 15400 | 15212 |
| PE | Mapbiomas_water | 23446 | 21362 | 20279 | 20198 | 17421 | 14974 | 14698 |
| AC | Mapbiomas_water | 17791 | 17739 | 17739 | 17739 | 17672 | 17086 | 17086 |
| ES | Mapbiomas_water | 12015 | 11734 | 11572 | 11567 | 10987 | 10987 | 10968 |
| RR | Mapbiomas_water | 10299 | 9810 | 9806 | 9805 | 8125 | 6567 | 6564 |
| RJ | Mapbiomas_water | 9278 | 8135 | 8126 | 7989 | 5119 | 4851 | 4763 |
| AL | Mapbiomas_water | 6465 | 6328 | 6328 | 6322 | 5428 | 3912 | 3906 |
| SE | Mapbiomas_water | 5908 | 5792 | 5527 | 5486 | 5285 | 4340 | 4234 |
| AP | Mapbiomas_water | 3219 | 2223 | 2188 | 2177 | 844 | 844 | 816 |
| DF | Mapbiomas_water | 1189 | 1144 | 1000 | 1000 | 787 | 787 | 787 |
| RS | Solvik_et_al | 233682 | 220391 | 129160 | 129160 | 107946 | 97904 | 97904 |
| GO | Solvik_et_al | 55996 | 53697 | 47814 | 47803 | 43577 | 43443 | 43429 |
| SP | Solvik_et_al | 54964 | 40546 | 38087 | 38049 | 27364 | 27129 | 27113 |
| MT | Solvik_et_al | 49093 | 47721 | 45170 | 45165 | 41933 | 41877 | 41817 |
| MG | Solvik_et_al | 46996 | 45218 | 40422 | 40412 | 36386 | 36386 | 36233 |
| CE | Solvik_et_al | 38447 | 35068 | 34956 | 34956 | 25198 | 25005 | 24991 |
| MS | Solvik_et_al | 30783 | 28816 | 28641 | 28637 | 25370 | 25370 | 25285 |
| PA | Solvik_et_al | 29255 | 29145 | 25347 | 25347 | 25162 | 25061 | 25043 |
| RO | Solvik_et_al | 26505 | 26483 | 25883 | 25882 | 25702 | 25702 | 25697 |
| MA | Solvik_et_al | 21597 | 21222 | 21115 | 21111 | 20093 | 20093 | 20089 |
| PR | Solvik_et_al | 20571 | 13598 | 13484 | 13471 | 7568 | 7494 | 7482 |
| TO | Solvik_et_al | 17523 | 17340 | 16926 | 16926 | 16048 | 15948 | 15948 |
| SC | Solvik_et_al | 13225 | 11088 | 10727 | 10725 | 7166 | 7166 | 7165 |
| BA | Solvik_et_al | 12782 | 12355 | 11984 | 11972 | 11549 | 11549 | 11494 |
| RN | Solvik_et_al | 10789 | 10698 | 10697 | 10696 | 9788 | 9713 | 9705 |
| PB | Solvik_et_al | 10165 | 9831 | 9828 | 9801 | 8668 | 8542 | 8479 |
| AC | Solvik_et_al | 8736 | 8735 | 8735 | 8735 | 8734 | 8734 | 8734 |
| PE | Solvik_et_al | 6394 | 6310 | 6283 | 6273 | 5885 | 5885 | 5847 |
| PI | Solvik_et_al | 5624 | 5112 | 5098 | 5097 | 3885 | 3885 | 3869 |
| RJ | Solvik_et_al | 3920 | 3863 | 3858 | 3858 | 3694 | 3694 | 3691 |
| ES | Solvik_et_al | 3338 | 3319 | 3294 | 3294 | 3186 | 3186 | 3184 |
| AM | Solvik_et_al | 1977 | 1964 | 1932 | 1932 | 1914 | 1914 | 1913 |
| RR | Solvik_et_al | 1188 | 1186 | 1181 | 1181 | 1178 | 1178 | 1178 |
| AL | Solvik_et_al | 491 | 489 | 489 | 489 | 485 | 485 | 485 |
| DF | Solvik_et_al | 476 | 456 | 333 | 333 | 249 | 249 | 249 |
| SE | Solvik_et_al | 151 | 150 | 150 | 150 | 146 | 146 | 146 |
| AP | Solvik_et_al | 133 | 131 | 105 | 105 | 103 | 103 | 103 |