他透露：在火星上，表层土壤也是碱性的，而且含盐量低，但是在较深处，随着“冰桌”的临近就会变成含盐分的酸性土壤。
There , the surface soil is also alkaline and low in salts , but deeper it can turn saline and acidic as the " ice table " is approached , he said .
冰桌