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In this study, we develop a vegetation monitoring framework which is applicable at a planetary scale, and is based on the BACI (Before-After, Control-Impact) design. This approach utilizes Google Earth Engine, a state-of-the-art cloud computing platform. A web-based application for users named EcoDash was developed. EcoDash maps vegetation using Enhanced Vegetation Index (EVI) from Moderate Resolution Imaging Spectroradiometer (MODIS) products (the MOD13A1 and MYD13A1 collections) from both Terra and Aqua sensors from the years 2000 and 2002, respectively. to detect change in vegetation, we define an EVI baseline period, and then draw results at a planetary scale using the web-based application by measuring improvement or degradation in vegetation based on the user-defined baseline periods. We also used EcoDash to measure the impact of deforestation and mitigation efforts by the Vietnam Forests and Deltas (VFD) program for the Nghe An and Thanh Hoa provinces in Vietnam. Using the period before 2012 as a baseline, we found that as of March 2017, 86% of the geographical area within the VFD program shows improvement, compared to only a 24% improvement in forest cover for all of Vietnam. Overall, we show how using satellite imagery for monitoring vegetation in a cloud-computing environment could be a cost-effective and useful tool for land managers and other practitioners

Highlights A sulfuric acid leaching process is applied on unsorted spent batteries. The pregnant leach solution (PLS) contains Zn, Mn, Cd, Ni and Co. Zn and Cd are separated from PLS using solvent extraction and electrodeposition. Mn and Ni are recovered using chemical precipitation as metal carbonates. AbstractThis investigation presents the development of a waste batteries recycling technology, that could lead to the minimization of waste discharged and contamination problems and to the depletion of natural resources. This study mainly focused on the recovery of metals from a pregnant leach solution (PLS) obtained from a sulphuric leaching process applied to unsorted spent batteries. The PLS mainly contains Zn, Mn, Cd, Ni and Co. Cyanex 272 (di-2,4,4trimethylpentyl phosphinic acid) was used to selectively recover Zn from the mixed solution.The Zn-Cyanex 272 was stripped and electrodeposited in metallic form and approximately 134 kg of Zn were recovered. Cd and Mn were co-extracted in the organic solvent D2EHPA (2ethylhexylphosphonic acid) from the Zn-depleted solution and they were stripped using H 2 SO 4 .Consequently, Cd was selectively electrodeposited from a sulphate-stripped solution where the amount of Cd recovered was equal to 21.6 kg Cd per ton of waste battery powder. Residual Mn was recovered in the carbonate form by the addition of Na 2 CO 3 (238 kg of Mn t -1 of waste battery powder). In the following step, Cyanex 272 was used to remove Co and other impurities from the Zn-Cd-Mn depleted solution, while Ni was not extracted. Finally, Ni was precipitated from the pure NiSO 4 solution with Na 2 CO 3 and 23.8 kg of Ni were recovered per ton of waste battery powder. The costs of the process develop to recover metals (including only chemical costs and energy consumption) are estimated at $814 t -1 of battery powder, while the metal revenues obtained are estimated at $2,132 t -1 of battery powder. The chemical cost /metal revenue ratio is lower than 50%, which indicates that the process is feasible.

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