One of them is a lack of land areas available for restoration.

其中一个困难就是可供修复的土地面积不足。

This would also increase the area available for seaweed farms, by allowing them to be located well away from coastlines.

这也会增加海草养殖场的可用面积，在离海岸线较远的地方也可以种植。

Additionally, gas exchange is efficient because of the large surface area available for gas exchange.

此外，气体交换是有效的，因为大表面积可用于气体交换。

Hemoglobin gives erythrocytes their red color. Erythrocytes are small, disk-shaped cells with no nucleus. This shape maximizes the surface area available for absorption of oxygen and carbon dioxide.

血红蛋白使红细胞呈红色。红细胞是小的盘状无核细胞。这种形状最大化了吸收氧气和二氧化碳的表面积。