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Jeffrey A. Hicke, David B. Lobell, and Gregory P. Asner

1. Introduction Croplands are important land-cover types in the global carbon (C) cycle. Worldwide, croplands cover 12% of the total vegetated land surface ( Ramankutty and Foley, 1998 ). Studies of net primary production (NPP), the net amount of carbon fixed by plants, estimated that 7.8 Pg C yr −1 is associated with croplands, or 16% of the global total ( Potter et al., 1993 ). In the coterminous United States, croplands contributed an average of 20% of the total NPP from 1982 to 1998

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C. E. LAMOUREUX

,000 acres of cropland for units of area varying in size from a single township to the State as a whole. It isnoted that the adjusted dollar data on damage per 1,000 acres do not reflect meteorological factors alone, but includeproduction factors as well. A further adjustment is made, using a crop production index developed by the IowaDepartment of Agriculture. The resulting damage data, as influenced by meteorological factors alone, shows lessvariation between the various sections of the State

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Jatin Kala, Mark Decker, Jean-François Exbrayat, Andy J. Pitman, Claire Carouge, Jason P. Evans, Gab Abramowitz, and David Mocko

. Fig. 8. Gridded cumulative difference in monthly mean LAI and carbon fluxes (Gg month −1 ) between the control simulation and the ensemble mean (cumulative changes in LAI < 5 have been masked out to highlight the largest changes). Fig. 9. Time series of monthly mean absolute differences in LAI, autotrophic respiration (AR), heterotrophic respiration (HR), and gross primary production (GPP) between the control simulation and the ensemble mean for (a) southwestern and (b) southeastern croplands. 4

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Christopher Potter, Steven Klooster, Alfredo Huete, and Vanessa Genovese

in North America ( Potter et al. 2001 ; Amthor et al. 2001 ; Hicke et al. 2002 ) and against atmospheric inverse model estimates of global NEP ( Potter et al. 2003 ). For the first time in our NPP model, the e max term has been adjusted for different cropland types to account for the effects of fertilizer nutrient additions on crop yield and biomass production. Following the synthesis results of Stewart et al. ( Stewart et al. 2005 ), who summarized a total of 362 seasons of crop production

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W. L. Ellenburg, R. T. McNider, J. F. Cruise, and John R. Christy

changes in albedo would go into sensible heat. The southeastern United States resides in a humid, subtropical climate, and in this energy-limited, water-rich environment, the latent energy is mostly governed by the available water. Under this assumption, the results show that the change in sensible (as a result of albedo) and latent energies are in direct competition with each other. In the spring and early summer months, the croplands are in peak production, and the latent energy associated with

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Peiyun Zhu, Susan J. Cheng, Zachary Butterfield, Gretchen Keppel-Aleks, and Allison L. Steiner

. 1998 ). Because COT measures the degree to which light is attenuated, it captures both the scattering (i.e., production of diffuse light) and absorption (i.e., reduction of diffuse and direct light) of light by clouds and can be considered an integrated measure of the physical impacts that clouds have on surface radiation. Global-scale data on COT can be remotely sensed from space using instruments such as NASA’s Moderate Resolution Imaging Spectroradiometer (MODIS) ( Pincus et al. 2012 ), which

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Philip Potter, Navin Ramankutty, Elena M. Bennett, and Simon D. Donner

recoverable fraction. 3.5. “Hot spot” nature of fertilizer application and manure production Most fertilized grid cells have low application rates—for example, more than 50% of cropland area fertilized with N is fertilized at a rate of less than 2.5 kg ha −1 (figure not shown). On the other hand, a small proportion of the fertilized land area receives a disproportionately large proportion of the total fertilizers applied ( Figure 6 ). In fact, 8.5% and 10.2% of the grid cells fertilized

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C.-H. Ho, S.-J. Park, S.-J. Jeong, J. Kim, and J.-G. Jhun

budget. The expansion of croplands and the associated land-use changes (e.g., large-scale deforestation and irrigation) can affect long-term climate variations and has been a topic of intense research. The agricultural practice of double cropping, widely used to increase crop production, causes short-term but systematic variations in land surface characteristics during a period between two adjacent growing seasons. Double cropping is composed of two growing seasons separated by a short harvest season

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Ellen Jasinski, Douglas Morton, Ruth DeFries, Yosio Shimabukuro, Liana Anderson, and Matthew Hansen

1. Introduction In the three decades since soy production began in Brazil, soy has advanced to become the nation’s principal crop, both in planted area and in quantity produced. Since 1990, the amount of land planted with soy in Brazil has doubled and production has quadrupled. Mechanization has been a key element in both the rapidity of expansion and the increase in yield. Researchers and farmers first introduced soy into the southern region of the country, and have since extended planting

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David Barriopedro, Célia M. Gouveia, Ricardo M. Trigo, and Lin Wang

1. Introduction During 2009 and 2010, an intense and prolonged drought episode affected several provinces of northern (Hebei, Shanxi, and Liaoning) and southwestern (Yunnan, Guizhou, Guangxi, and Sichuan) China, including the municipalities of Beijing and Chongqing ( Qiu 2010 ). Northern China is an important area of grain production, while the southwest region represents one of the major water resources of the country, supplying water to the Yangtze River, the Pearl River head, and their

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