Biomass Production In Plantations Research Articles

Biomass production in plantations: Land constraints increase dependency on irrigation water

AbstractIntegrated assessment model scenarios project rising deployment of biomass‐using energy systems in climate change mitigation scenarios. But there is concern that bioenergy deployment will increase competition for land and water resources and obstruct objectives such as nature protection, the preservation of carbon‐rich ecosystems, and food security. To study the relative importance of water and land availability as biophysical constraints to bioenergy deployment at a global scale, we use a process‐detailed, spatially explicit biosphere model to simulate rain‐fed and irrigated biomass plantation supply along with the corresponding water consumption for different scenarios concerning availability of land and water resources. We find that global plantation supplies are mainly limited by land availability and only secondarily by freshwater availability. As a theoretical upper limit, if all suitable lands on Earth, besides land currently used in agriculture, were available for bioenergy plantations (“Food first” scenario), total plantation supply would be in the range 2,010–2,300 EJ/year depending on water availability and use. Excluding all currently protected areas reduces the supply by 60%. Excluding also areas where conversion to biomass plantations causes carbon emissions that might be considered unacceptably high will reduce the total plantation supply further. For example, excluding all areas where soil and vegetation carbon stocks exceed 150 tC/ha (“Carbon threshold savanna” scenario) reduces the supply to 170–290 EJ/year. With decreasing land availability, the amount of water available for irrigation becomes vitally important. In the least restrictive land availability scenario (“Food first”), up to 77% of global plantation biomass supply is obtained without additional irrigation. This share is reduced to 31% for the most restrictive “Carbon threshold savanna” scenario. The results highlight the critical—and geographically varying—importance of co‐managing land and water resources if substantial contributions of bioenergy are to be reached in mitigation portfolios.

Comparison of the growth of fast-growing poplar and willow in two sites of Central Kazakhstan

In temperate climatic conditions, plantations of poplar and willow species provide sustainable production of biomass. Short rotation coppice plantations on agricultural lands have a great potential to increase the amount of biomass available for the production of biofuels, bioenergy and bioproducts. We studied and measured the growth of poplar and willow clones in two experimental research sites in Batys and Astaninskiy in the steppe zone of Astana in northern Kazakhstan. We measured tree heights, stem diameters at breast height and crown diameter. The mean height of 6-years-old trees of the “Kazakhstanskiy” hybrid poplar was 4.03 m in the Batys site, which is 1.6 m less than the height of poplars from the Astaninskiy experimental site that were measured in autumn. The results of this study show different reactions of selected clones/cultivars of poplar and willow to climatic conditions of northern Kazakhstan as well as their usability for biomass production in plantations under limiting hydrological conditions.