Described here are compositions, methods and apparatus for biological and physical geoengineering. A vertical spar buoy or spar buoy network is provided. The buoys or array of buoys are designed to resist wave motion while supporting an analytical platform at a depth such that particulate flux of fixed carbon is indicative of sequestration in the oceans depths for one hundred years or more. Sedimentary deadfall through the 100-Year Horizon is measured to validate the flux of fixed carbon. Issuance of validated carbon sequestration certificates and monetization and trading of those certificates are described. Also provided are compositions and methods for increasing bioactive surface area and nutrient levels so as to promote carbon sequestration. Regeneration of carbon dioxide in the mesopelagic water column is reduced by providing complex habitat in the photic zone, thus ensuring higher complexity of trophic levels and sedimentary deadfall having larger particulate size.