To save content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about saving content to .
To save content items to your Kindle, first ensure email@example.com
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about saving to your Kindle.
Note you can select to save to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be saved to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Low-spatial resolution satellite imagery from the NOAA-10 polar-orbiting meteorological satellite was analyzed to determine if central New Mexico grasslands infested by broom snakeweed could be discriminated from unaffected areas. Distinctive phenological characteristics of broom snakeweed, including an early season growth flush and late season flowering, enable moderate to heavily infested areas to be separated from grasslands having few or no weeds present. The procedure used shows promise as a tool for locating and monitoring brown snakeweed and other weeds growing on shortgrass prairie.
As governments and institutions work to ameliorate the effects of anthropogenic CO2 emissions on global climate, there is an increasing need to understand how land-use and land-cover change is coupled to the carbon cycle, and how land management can be used to mitigate their effects. This book brings an interdisciplinary team of fifty-eight international researchers to share their novel approaches, concepts, theories and knowledge on land use and the carbon cycle. It discusses contemporary theories and approaches combined with state-of-the-art technologies. The central theme is that land use and land management are tightly integrated with the carbon cycle and it is necessary to study these processes as a single natural-human system to improve carbon accounting and mitigate climate change. The book is an invaluable resource for advanced students, researchers, land-use planners and policy makers in natural resources, geography, forestry, agricultural science, ecology, atmospheric science and environmental economics.
The last few millennia have seen significant human intervention in the Earth system. For most of this time, the influence of humans on ecological processes, including the carbon (C) cycle, was limited to local-scale impacts through hunting and gathering and then through cultivation and animal husbandry. However, the start of the Industrial Revolution in the eighteenth century saw the collective action of humans begin to alter the C cycle at a global scale by changing the composition of the Earth's atmosphere (Hegerl et al. 2007). It is arguable that human impacts on global levels of atmospheric methane (CH4) and carbon dioxide (CO2) can be traced back thousands (not just hundreds) of years, largely driven by extensive land management through use of fire (Ruddiman 2003). Although the dominant anthropogenic influence on the global C cycle has resulted from the burning of fossil fuels, it has been estimated that land changes and land degradation have directly affected 39 to 50 percent of the land surface (Vitousek et al. 1997) and contributed to 30 percent of the total anthropogenic efflux of CO2 to the atmosphere (see Chapter 3). Humans have become integral actors in the C cycle – at both local and global scales – to such a degree that many now argue that no point on the surface of the Earth, or ecosystem, has escaped the effects of human activity (e.g., Ellis et al. 2010; Turner, Lambin, and Reenberg 2007).
Central to the theme of this book is the notion that as humans alter the surface of the land through land use and land management, they change the pools and fluxes of C across the Earth. Human actions affect the fundamental structure and function of the ecosystems, therefore altering the amount of C stored above- and belowground; the rate of transfer between the surface and the atmosphere; and how much ends up in the rivers, streams, lakes, and oceans. For example, when a forest is burned to clear the land, a large portion of the aboveground C is released to the atmosphere, some remains on site, and some is leached into the hydrological system. Not all of these fractions are known with a high degree of precision, but they vary by ecological context and frequency, duration, and intensity of fire.
We have measured the transient events of the α-β martensitic transformation in nanocrystalline Ti films via single shot electron diffraction patterns with 1.5 ns temporal resolution. This was accomplished with a newly constructed dynamic transmission electron microscope (DTEM), which combines pulsed laser systems and pump-probe techniques with a conventional TEM. The DTEM thereby enables studies of transformations that are (1) far too fast to be captured by conventional bulk techniques, and (2) difficult to study with current ultrafast electron diffraction (UED) instruments (which typically require an accumulation of multiple shots for each diffraction pattern). Martensitic transformations in nanocrystalline materials meet both criteria, with their rapid nucleation, characteristic interface velocities ∼1 km/s, and significant irreversible microstructural changes. Free-standing 40-nm-thick Ti films were laser-heated at a rate of ∼1010 K/s to a temperature above the 1155 K transition point, then probed at various time intervals with a 1.5-ns-long intense electron pulse. Diffraction patterns show an almost complete transition to the β phase within 500 ns. Post-mortem analysis (after the sample is allowed to cool) shows a reversion to the α phase coupled with substantial grain growth, lath formation, and texture modification. The cooled material also shows a complete lack of apparent dislocations, suggesting the possible importance of a "massive" short-range diffusion mechanism.
Email your librarian or administrator to recommend adding this to your organisation's collection.