Jeehwan Bae : Paper of the week & Book of the month

Author  : Goodale, C. L. Davidson, E. A. Year  : 2002 Title  : Carbon cycle: Uncertain sinks in the shrubs Journal  : Nature Comment   : Grasses usually allocate more of their production to roots than to shoots, and most of the roots are in the top metre of soil. When shrubs invade grasslands, carbon input to the topsoil may decrease because the woody species allocate less of their total production below ground, and what they do send to roots is distributed more deeply.

Author  : Zhao, S. Q. Zhu, C. Zhou, D. C. Huang, D. Werner, J. Year  : 2013 Title  : Organic Carbon Storage in China's Urban Areas Journal  : Plos One Comment   : They estimated that total carbon storage in China’s urban areas was 577 ± 60 Tg C in 2006. Soil was the largest contributor to total carbon storage (56%), followed by buildings (36%), and vegetation (7%), while carbon storage in humans was relatively small (1%). This value might be useful for estimating urban carbon storage at regional to global scales.

Author  : Edmondson, J. L. Davies, Z. G. McHugh, N. Gaston, K. J. Leake, J. R. Year  : 2012 Title  : Organic carbon hidden in urban ecosystems Journal  : Scientific Reports Comment   : To date, the total quantity of OC stored in urban soils (under both impervious surfaces and greenspaces), together with that in above-ground vegetation, has never been systematically measured.  They report the first city-wide organic carbon (OC) budget for vegetation and soils, including under impervious surfaces. The majority of OC (82%) was held in soils, with 13% found under impervious surfaces, and 18% stored in vegetation.

Author  : Augusto, L. Ranger, J. Binkley, D. Rothe, A. Year  : 2002 Title  : Impact of several common tree species of European temperate forests on soil fertility Journal  : Annals of Forest Science Comment   : The physical characteristics of soils also were modified depending on the overstory species, probably through modifications of the soil fauna. The rates of organic matter mineralization and nitrification seem to be dependent on tree species. The impact of a tree species on soil fertility varied depending on the type of bedrock, climate and forest management.

Author  : Raulundrasmussen, K. Vejre, H. Year  : 1995 Title  : EFFECT OF TREE SPECIES AND SOIL PROPERTIES ON NUTRIENT IMMOBILIZATION IN THE FOREST FLOOR Journal  :Plant and Soil Comment   :The accumulation of C, N and P in the forest floor was significantly higher at the sandy site than at the loamy site under all species. Strong root infiltration in the forest floors at the sandy site compared to almost none at the loamy site, is probably responsible for the differences in mineralization rate due to competition between the organic matter decomposers and the tree-roots/mycorrhiza for nutrients.

Author  : Donald Hagan, Francisco Escobedo, Gurpal Toor, Henry Mayer, Joy Klein and Cynnamon Dobbs Year  : 2010 Title  : Soil Bulk Density and Organic Matter in Urban Miami-Dade County, Florida Journal  :This document is SL 327, one of a series of the Soil and Water Science Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Comment   : In fact, most soil surveys do not even describe urban soils and delineate them as blank areas on regional soil maps. Recent studies have shown, however, that the physical, chemical, and biological properties of urban soils are quite variable, with conditions ranging from highly modified to relatively natural. In general, soil organic matter was highest in recreational and residential land uses and lowest in forested and agricultural land uses. Some areas in Miami-Dade with low bulk density (e.g. older residential areas with high tree cover and recreatio...

Author  : Giregon Olupot, Heiko Daniel, Peter Lockwood, Melinda McHenry and Malem McLeod Year  : 2010 Title  : Root contributions to long-term storage of soil organic carbon: theories, mechanisms and gaps Journal  :2010 19th World Congress of Soil Science, Soil Solutions for a Changing World Comment   :SOC (soil organic carbon) tends to be concentrated in the topsoil where the highest FRB (fine root biomass) is located. Over 60% of all live root biomass occurred above 0.1 m depth. Rooting depth and profile distribution may be used to indicate potential to locate and sequester SOC in subsurface horizons (Rasse et al. 2005; Denef and Six 2006), because during their growth, roots punch through moist soil deforming and repacking it (Hinsinger et al. 2009), while depositing C along their way (Hirth et al. 2005).

Author  : Majdi, H. Pregitzer, K. Moren, A. S. Nylund, J. E. Agren, G. I. Year  : 2005 Title  : Measuring fine root turnover in forest ecosystems Journal  :Plant and Soil Comment   : Fine root production has been estimated to account for up to 33% of global annual Net Primary Production, NPP. Eissenstat et al. (2000) found that root longevity was enhanced by mycorrhizal colonization and negatively correlated with nitrogen concentration, root maintenance respiration and specific root length.

Author  : Chen, W. J. Zhang, Q. F. Cihlar, J. Bauhus, J. Price, D. T. Year  : 2004 Title  : Estimating fine-root biomass and production of boreal and cool temperate forests using aboveground measurements: A new approach Journal  : Plant and Soil Comment   : Fine-root biomass of overstory trees in stand was first separated from that of understory and standardized to a common fine-root definition of < 2 mm or < 5 mm diameter. The estimates of tree fine-root production agree well with reported values, with r2 value of 0.53 for < 2 mm and 0.54 for < 5 mm diameter (n = 162) at the stand level.

Author  : Trumbore, S. Da Costa, E. S. Nepstad, D. C. De Camargo, P. B. Martinelli, Liza Ray, D. Restom, T. Silver, W. Year  : 2006 Title  : Dynamics of fine root carbon in Amazonian tropical ecosystems and the contribution of roots to soil respiration Journal  : Global Change Biology Comment   : Estimates of the mean residence time of C in forest fine roots (inventory divided by loss rate) are substantially shorter (1–3 years) than the age of standing fine root C stocks obtained from radiocarbon (4–11 years).

Author  : Goodale, C. L. Davidson, E. A. Year  : 2002 Title  : Carbon cycle: Uncertain sinks in the shrubs Journal  : Nature Comment   : 'woody encroachment', Grasses usually allocate more of their production to roots than to shoots8, and most of the roots are in the top metre of soil. When shrubs invade grasslands, carbon input to the topsoil may decrease because the woody species allocate less of their total production below ground, and what they do send to roots is distributed more deeply.

Author  : Bartel, P. Year  : 2004 Title  : Soil carbon sequestration and its role in economic development: a donor perspective Journal  : Journal of Arid Environments Comment   : Some scientists suggest that the highest potential for soil carbon sequestration can be found in degraded lands. Improved dryland farming, range management, and irrigation could reverse this trend by replenishing depleted soil carbon stocks.

Author  : Shu Kee Lam, Deli Chen, Arvin R. Mosier & Richard Roush Year  : 2013 Title  : The potential for carbon sequestration in Australian agricultural soils is technically and economically limited Journal  : SCIENTIFIC REPORTS Comment   : Their results indicate that the potential of these improved practices to store carbon is limited to the surface 0–10 cm of soil and diminishes with time. The annual relative gain in soil carbon stock was greatest during the first 10 years after implementation of improved management treatments.

Author  :  Carbone, M. S. Winston, G. C. Trumbore, S. E. Year  : 2008 Title  : Soil respiration in perennial grass and shrub ecosystems: Linking environmental controls with plant and microbial sources on seasonal and diel timescales Journal  : Journal of Geophysical Research-Biogeosciences Comment   : As soil moisture declined over the growing season, diel patterns became increasingly decoupled temporally from temperature due to increased water-limitation on surface heterotrophic sources and hypothesized strong photosynthetic control over soil respiration rates.

Author  : Monson, R. K. Lipson, D. L. Burns, S. P. Turnipseed, A. A. Delany, A. C. Williams, M. W. Schmidt, S. K. Year  : 2006 Title  : Winter forest soil respiration controlled by climate and microbial community composition Journal  : Nature Comment   : Winter respiratory carbon dioxide losses from these ecosystems are high, and over half of the carbon assimilated by photosynthesis in the summer can be lost the following winter. They study the effect of changes in snow cover on soil carbon cycling within the context of natural climate variation. Their observations reveal that a warmer climate may change the beneath-snow soil temperature in forest ecosystems because of changes in the depth of the insulating snow cover, changing soil respiration rates and, concomitantly, soil C sequestration rates.

Author  : Johan six Year  :  2013 Title  : Conservation: Spare our restored soil Journal  : Nature Comment   : Land-use change influences greenhouse-gas fluxes from soils to the atmosphere. More recently, no-tillage cultivation has been advocated as a potential tool for mitigating or adapting to climate change. Similarly, converting conventionally tilled systems to grasslands (as in the CRP) generally leads to increases in soil carbon. It is also expected to decrease nitrous oxide emissions and increase the uptake of methane into the soil, leading to a general decrease in globalwarming impact. A limitation of the study is that the researchers took measurements for only one year.

Author  : Dijkstra, F. A. Cheng, W. X. Year  :  2007 Title  : Interactions between soil and tree roots accelerate long-term soil carbon decomposition Journal  : Ecology Letters Comment   :  Decomposition of soil organic carbon (SOC) is the main process governing the release of CO2 into the atmosphere from terrestrial systems.  They provide experimental evidence for a rhizosphere priming effect, in which interactions between soil and tree roots substantially accelerate SOC decomposition. Loss of old SOC was greater than the formation of new C, suggesting that increased C inputs from roots could result in net soil C loss.

Author  : Hobbie, S. E. Ogdahl, M. Chorover, J. Chadwick, O. A. Oleksyn, J. Zytkowiak, R. Reich, P. B. Year  :  2007 Title  : Tree species effects on soil organic matter dynamics: The role of soil cation composition Journal  : Ecosystems Comment   : Understanding how species influence soil organic matter dynamics is important to predicting how soil C sequestration and fertility will respond to management decisions and as well as global environmental changes that alter plant species composition across the landscape. They found that tree species contributed significantly to variation in soil C and N dynamics, but not always via the hypothesized mechanisms. Trees (and tree species) influenced SOM dynamics in the mineral horizons primarily via their influence on soil cation chemistry and chemical stabilization, rather than via variation in detritus chemistry and biochemical recalcitrance.

Author  : Bailey, N. J. Motavalli, P. P. Udawatta, R. P. Nelson, K. A. Year  :  2009 Title  : Soil CO2 emissions in agricultural watersheds with agroforestry and grass contour buffer strips Journal  : Agroforestry Systems Comment   : Soil water-filled pore space (WFPS), The highest cumulative CO2 production for the grass soil (1,279 mg CO2-C kg soil-1) occurred at 80% WFPS, and was approximately 2 to 2.6 times greater than the agroforestry and cropped soils at 80% WFPS. In re-established forest ecosystems, Oren et al. (2001) reported that with elevated CO2 levels, the limiting factor regulating C sequestration was low soil fertility. Knops and Tilman (2000) found that in formerly cultivated fields, soil total organic C recovered faster after the establishment of grasses with sufficient available N compared to fields that had limited available N.

Author  : Schlesinger, W. H. Andrews, J. A. Year  :  2000 Title  : Soil respiration and the global carbon cycle Journal  : Biogeochemistry Comment   :  Typically, only 10–20% of the nitrogen applied to forests accumulates in wood; a larger portion often accumulates in the soil organic matter, in which the C/N ratio is 12 to 15. Additions of nitrogen to forest soils often lower the C/N ratio without causing major changes in total amount of soil carbon