Carbon (C) sequestration in soils through the increase of the soil organic carbon (SOC) pool has generated broad interest to mitigate the effects of climate change. Biosolids soil application may represent a persistent increase in the SOC pool. While a vast literature is available on the value of biosolids as a soil conditioner or nutrient source in agricultural systems, there is still limited knowledge on soil sequestration mechanisms of biosolids-borne C or the main factors influencing this capacity. The emerging challenges posed by global environmental changes and the stringent needs to enhance C storage call for more research on the potential of soil biosolids incorporation as a sustainable C storage practice. This review addresses the potential of C sequestration of agricultural soils and opencast mines amended with biosolids and its biological regulation. 1. Introduction Increasing concern about global climate change has led to growing interest in developing feasible methods to reduce the atmospheric levels of greenhouse gases (GHGs) [1]. Among GHGs, atmospheric carbon dioxide (CO2) accounts for 60% of the global warming [2]. The atmospheric concentration of CO2 increased from 280 parts per million (ppm) in the preindustrial era to the present 395？ppm [3]. This increase is attributed to combustion of carbon based fuels, cement manufacturing, deforestation, burning of biomass, and land-use conversion, including soil tillage and animal husbandry. Soil C capture and storage is gaining global attention because of its role as a long-term C reservoir, low cost, and environmentally friendly means to minimize climate change. Soil C pool is the largest terrestrial C pool, constituting approximately two-thirds of the total C in ecosystems [4]. It is estimated at 2500？Pg to 1-m depth, with the biotic pool estimated at 560？Pg and characterized by fast turnover rates as compared to other natural compartments. The oceanic and geological pools are estimated at 39000？Pg and 5000–10000？Pg, respectively, whereas the atmospheric pool is estimated at 780？Pg [5]. Therefore, total soil C pool is about 4, 1 times the biotic pool and 3 times the atmospheric pool. Soil organic carbon (SOC) includes plant, animal, and microbial residues in all stages of decomposition. SOC represents a balance between inputs, mostly via primary productivity or organic amendments, and outputs via decomposition [6]. Land application of organic amendments is a management practice that enhances SOC in the short term [7, 8]. In the last decades, the production of organic urban wastes such as
References
[1]
WMO, Greenhouse Gas Bulletin, World Meteorological Organization, Geneva, Switzerland, 2009.
[2]
P. N. Pearson and M. R. Palmer, “Atmospheric carbon dioxide concentrations over the past 60 million years,” Nature, vol. 406, no. 6797, pp. 695–699, 2000.
[3]
M. Czaun, A. Goeppert, R. B. May, et al., “Organoamines-grafted on nano-sized silica for carbon dioxide capture,” Journal of CO2 Utilization, vol. 1, pp. 1–7, 2013.
[4]
D. S. Schimel, B. H. Braswell, and E. A. Holland, “Climatic, edaphic, and biotic controls over storage and turnover of carbon in soils,” Global Biogeochemical Cycles, vol. 8, no. 3, pp. 279–293, 1994.
[5]
R. Lal, “Managing soils and ecosystems for mitigating anthropogenic carbon emissions and advancing global food security,” BioScience, vol. 60, no. 9, pp. 708–721, 2010.
[6]
R. Amundson, “The carbon budget in soils,” Annual Review of Earth and Planetary Sciences, vol. 29, pp. 535–562, 2001.
[7]
S. Torri and R. Lavado, “Carbon sequestration through the use of biosolids in soils of the Pampas region, Argentina,” in Environmental Management: Systems, Sustainability and Current Issues, H. C. Dupont, Ed., pp. 221–336, Nova Science, Hauppauge, NY, USA, 2011.
[8]
G. Tian, T. C. Granato, A. E. Cox, R. I. Pietz, C. R. Carlson Jr., and Z. Abedin, “Soil carbon sequestration resulting from long-term application of biosolids for land reclamation,” Journal of Environmental Quality, vol. 38, no. 1, pp. 61–74, 2009.
[9]
L. Giusti, “A review of waste management practices and their impact on human health,” Waste Management, vol. 29, no. 8, pp. 2227–2239, 2009.
[10]
N.-Y. Wang, C.-H. Shih, P.-T. Chiueh, and Y.-F. Huang, “Environmental effects of sewage sludge carbonization and other treatment alternatives,” Energies, vol. 6, no. 2, pp. 871–883, 2013.
[11]
J. Hong, M. Otaki, and O. Jolliet, “Environmental and economic life cycle assessment for sewage sludge treatment processes in Japan,” Waste Management, vol. 29, no. 2, pp. 696–703, 2009.
[12]
E. Ramlal, D. Yemshanov, G. Fox, and D. McKenney, “A bioeconomic model of afforestation in Southern Ontario: integration of fiber, carbon and municipal biosolids values,” Journal of Environmental Management, vol. 90, no. 5, pp. 1833–1843, 2009.
[13]
O. Ayalon, Y. Avnimelech, and M. Shechter, “Solid waste treatment as a high-priority and low-cost alternative for greenhouse gas mitigation,” Environmental Management, vol. 27, no. 5, pp. 697–704, 2001.
[14]
R. S. Corrêa, R. E. White, and A. J. Weatherley, “Biosolids effectiveness to yield ryegrass based on their nitrogen content,” Scientia Agricola, vol. 62, no. 3, pp. 274–280, 2005.
[15]
C. G. Cogger, A. I. Bary, E. A. Myhre, and A. Fortuna, “Biosolids applications to tall fescue have long-term influence on soil nitrogen, carbon, and phosphorus,” Journal of Environmental Quality, vol. 42, pp. 516–522, 2013.
[16]
F. J. Larney and D. A. Angers, “The role of organic amendments in soil reclamation: a review,” Canadian Journal of Soil Science, vol. 92, no. 1, pp. 19–38, 2012.
[17]
P. E. Wiseman, S. D. Day, and J. R. Harris, “Organic amendment effects on soil carbon and microbial biomass in the root zone of three landscape tree species,” Arboriculture & Urban Forestry, vol. 38, no. 6, pp. 262–276, 2012.
[18]
K. Barbarick, K. Doxtader, E. Redente, and R. Brobst, “Biosolids effects on microbial activity in shrubland and grassland soils,” Soil Science, vol. 169, no. 3, pp. 176–187, 2004.
[19]
W. E. Cotching and J. R. Coad, “Metal element uptake in vegetables and wheat after biosolids application,” Journal of Solid Waste Technology and Management, vol. 37, no. 2, pp. 75–82, 2011.
[20]
M. J. Mcfarland, K. Kumarsamy, R. B. Brobst, A. Hais, and M. D. Schmitz, “Groundwater quality protection at biosolids land application sites,” Water Research, vol. 46, no. 18, pp. 5963–5969, 2012.
[21]
K. R. Islam, S. Ahsan, K. Barik, and E. L. Aksakal, “Biosolid impact on heavy metal accumulation and lability in soiln under alternate-year no-till corn—soybean rotation,” Water, Air, & Soil Pollution, vol. 224, pp. 1451–1461, 2013.
[22]
EU, “3rd Working Document of the EU Commission on Sludge Management,” ENV.E3/LM, Brussels, Belgium, 2000.
[23]
G. Pu, M. Bell, G. Barry, and P. Want, “Estimating mineralisation of organic nitrogen from biosolids and other organic wastes applied to soils in subtropical Australia,” Soil Research, vol. 50, no. 2, pp. 91–104, 2012.
[24]
R. Lal, “Carbon management in agricultural soils,” Mitigation and Adaptation Strategies for Global Change, vol. 12, no. 2, pp. 303–322, 2007.
[25]
D. S. Powlson, A. P. Whitmore, and K. W. T. Goulding, “Soil carbon sequestration to mitigate climate change: a critical re-examination to identify the true and the false,” European Journal of Soil Science, vol. 62, no. 1, pp. 42–55, 2011.
[26]
C. Feller and M. Bernoux, “Historical advances in the study of global terrestrial soil organic carbon sequestration,” Waste Management, vol. 28, no. 4, pp. 734–740, 2008.
[27]
B. Marschner, S. Brodowski, A. Dreves et al., “How relevant is recalcitrance for the stabilization of organic matter in soils?” Journal of Plant Nutrition and Soil Science, vol. 171, no. 1, pp. 91–110, 2008.
[28]
M. W. I. Schmidt, M. S. Torn, S. Abiven et al., “Persistence of soil organic matter as an ecosystem property,” Nature, vol. 478, no. 7367, pp. 49–56, 2011.
[29]
M. Pansu, P. Bottner, L. Sarmiento, and K. Metselaar, “Comparison of five soil organic matter decomposition models using data from a 14C and 15N labeling field experiment,” Global Biogeochemical Cycles, vol. 18, no. 4, 2004.
[30]
P. Puget, C. Chenu, and J. Balesdent, “Dynamics of soil organic matter associated with particle-size fractions of water-stable aggregates,” European Journal of Soil Science, vol. 51, no. 4, pp. 595–605, 2000.
[31]
B. T. Christensen, “Physical fractionation of soil and structural and functional complexity in organic matter turnover,” European Journal of Soil Science, vol. 52, no. 3, pp. 345–353, 2001.
[32]
S. I. Torri, Distribution and availability of Cd, Cu, Pb y Zn in sewage sludge amended soils [M Sci. Dissertation], University of Buenos Aires, Faculty of Agronomy, Buenos Aires, Argentina, 2001.
[33]
E. Alonso, I. Aparicio, J. L. Santos, P. Villar, and A. Santos, “Sequential extraction of metals from mixed and digested sludge from aerobic WWTPs sited in the south of Spain,” Waste Management, vol. 29, no. 1, pp. 418–424, 2009.
[34]
S. Torri, R. Alvarez, and R. Lavado, “Mineralization of carbon from sewage sludge in three soils of the Argentine pampas,” Communications in Soil Science and Plant Analysis, vol. 34, no. 13-14, pp. 2035–2043, 2003.
[35]
K. Lorenz, R. Lal, C. M. Preston, and K. G. J. Nierop, “Strengthening the soil organic carbon pool by increasing contributions from recalcitrant aliphatic bio(macro)molecules,” Geoderma, vol. 142, no. 1-2, pp. 1–10, 2007.
[36]
L. Thuriès, M. Pansu, C. Feller, P. Herrmann, and J.-C. Rémy, “Kinetics of added organic matter decomposition in a Mediterranean sandy soil,” Soil Biology & Biochemistry, vol. 33, no. 7-8, pp. 997–1010, 2001.
[37]
S. Manzoni, J. A. Trofymow, R. B. Jackson, and A. Porporato, “Stoichiometric controls on carbon, nitrogen, and phosphorus dynamics in decomposing litter,” Ecological Monographs, vol. 80, no. 1, pp. 89–106, 2010.
[38]
S. I. Torri and C. Alberti, “Characterization of organic compounds from biosolids of Buenos Aires city,” Journal of Soil Science and Plant Nutrition, vol. 12, no. 1, pp. 143–152, 2012.
[39]
R. E. Terry, D. W. Nelson, and L. E. Sommers, “Carbon cycling during sewage sludge decomposition in soils,” Soil Science Society of America Journal, vol. 43, no. 3, pp. 494–499, 1979.
[40]
R. S. Corrêa, R. E. White, and A. J. Weatherley, “Effects of sewage sludge stabilization on organic-N mineralization in two soils,” Soil Use and Management, vol. 28, no. 1, pp. 12–18, 2012.
[41]
R. Merckx, A. den Hartog, and J. A. van Veen, “Turnover of root-derived material and related microbial biomass formation in soils of different texture,” Soil Biology & Biochemistry, vol. 17, no. 4, pp. 565–569, 1985.
[42]
B. T. Christensen, “Carbon in primary and secondary organomineral complexes,” in Advances in Soil Science Structure and Organic Matter Storage in Agricultural Soils, M. R. Carter and B. A. Stewart, Eds., pp. 97–165, CRC Lewis, Boca Raton, Fla, USA, 1996.
[43]
F. J. Matus and R. C. Maire, “Interaction between soil organic matter, soil texture and the mineralization rates of carbon and nitrogen,” Agricultura Técnica, vol. 60, pp. 112–126, 2000.
[44]
M. B. Jones, “Potential for carbon sequestration in temperate grassland soils,” in Grassland Carbon Sequestration: Management, Policy and Economics, M. Abberton, R. Conant, and C. Batello, Eds., Food and Agriculture Organization of the United Nations, Rome, Italy, 2010.
[45]
D. T. Strong, P. G. Sale, and K. R. Helyar, “The influence of the soil matrix on nitrogen mineralisation and nitrification. IV. Texture,” Australian Journal of Soil Research, vol. 37, no. 2, pp. 329–344, 1999.
[46]
I. Thomsen, P. Schjonning, B. Jensen, K. Kristensen, and B. T. Christensen, “Turnover of organic matter in differently textured soils. II. Microbial activity as influenced by soil water regimes,” Geoderma, vol. 89, no. 3-4, pp. 199–218, 1999.
[47]
S. Wan, R. J. Norby, J. Ledford, and J. F. Weltzin, “Responses of soil respiration to elevated CO2, air warming, and changing soil water availability in a model old-field grassland,” Global Change Biology, vol. 13, no. 11, pp. 2411–2424, 2007.
[48]
K. M. Batten, K. M. Scow, K. F. Davies, and S. P. Harrison, “Two invasive plants alter soil microbial community composition in serpentine grasslands,” Biological Invasions, vol. 8, no. 2, pp. 217–230, 2006.
[49]
Z.-F. Xu, R. Hu, P. Xiong, C. Wan, G. Cao, and Q. Liu, “Initial soil responses to experimental warming in two contrasting forest ecosystems, Eastern Tibetan Plateau, China: nutrient availabilities, microbial properties and enzyme activities,” Applied Soil Ecology, vol. 46, no. 2, pp. 291–299, 2010.
[50]
R. D. de Laune, C. N. Reddy, and W. H. Patrick Jr., “Organic matter decomposition in soil as influenced by pH and redox conditions,” Soil Biology & Biochemistry, vol. 13, no. 6, pp. 533–534, 1981.
[51]
A. Saviozzi, G. Vanni, and R. Cardelli, “Carbon mineralization kinetics in soils under urban environment,” Applied Soil Ecology, vol. 73, pp. 64–69, 2014.
[52]
J. Rousk, P. C. Brookes, and E. B？？th, “Contrasting soil pH effects on fungal and bacterial growth suggest functional redundancy in carbon mineralization,” Applied and Environmental Microbiology, vol. 75, no. 6, pp. 1589–1596, 2009.
[53]
H. M. Throckmorton, J. A. Bird, L. Dane, M. K. Firestone, W. R. Horwath, and E. Cleland, “The source of microbial C has little impact on soil organic matter stabilisation in forest ecosystems,” Ecology Letters, vol. 15, no. 11, pp. 1257–1265, 2012.
[54]
J. Six, H. Bossuyt, S. Degryze, and K. Denef, “A history of research on the link between (micro)aggregates, soil biota, and soil organic matter dynamics,” Soil and Tillage Research, vol. 79, no. 1, pp. 7–31, 2004.
[55]
L. Vidal-Beaudet, C. Grosbelle, V. Forget-Caubel, and S. Charpentier, “Modelling long-term carbon dynamics in soils reconstituted with large quantities of organic matter,” European Journal of Soil Science, vol. 63, no. 6, pp. 787–797, 2012.
[56]
U. Thawornchaisit and K. Pakulanon, “Application of dried sewage sludge as phenol biosorbent,” Bioresource Technology, vol. 98, no. 1, pp. 140–144, 2007.
[57]
W. F. Jaynes and R. E. Zartman, “Origin of talc, iron phosphates, and other minerals in biosolids,” Soil Science Society of America Journal, vol. 69, no. 4, pp. 1047–1056, 2005.
[58]
K. J. Mun, N. W. Choi, and Y. S. Soh, “Feasibility study of lightweight aggregates using sewage sludge for non-structural concrete,” in RILEM International Symposium on Envronment-Conscious Materials and Systems, N. Kashino and Y. Ohama, Eds., pp. 155–162, RILEM, Bagneux, France, 2005.
[59]
M. Kleber, R. Mikutta, M. S. Torn, and R. Jahn, “Poorly crystalline mineral phases protect organic matter in acid subsoil horizons,” European Journal of Soil Science, vol. 56, no. 6, pp. 717–725, 2005.
[60]
G. Tian, A. J. Franzluebbers, T. C. Granato, A. E. Cox, and C. O'connor, “Stability of soil organic matter under long-term biosolids application,” Applied Soil Ecology, vol. 64, pp. 223–227, 2013.
[61]
R. Mikutta, M. Kleber, M. S. Torn, and R. Jahn, “Stabilization of soil organic matter: association with minerals or chemical recalcitrance?” Biogeochemistry, vol. 77, no. 1, pp. 25–56, 2006.
[62]
K. Kaiser and G. Guggenberger, “The role of DOM sorption to mineral surfaces in the preservation of organic matter in soils,” Organic Geochemistry, vol. 31, no. 7-8, pp. 711–725, 2000.
[63]
R. Wagai and L. M. Mayer, “Sorptive stabilization of organic matter in soils by hydrous iron oxides,” Geochimica et Cosmochimica Acta, vol. 71, no. 1, pp. 25–35, 2007.
[64]
S. Spielvogel, J. Prietzel, and I. K？gel-Knabner, “Soil organic matter stabilization in acidic forest soils is preferential and soil type-specific,” European Journal of Soil Science, vol. 59, no. 4, pp. 674–692, 2008.
[65]
K. Kaiser, K. Eusterhues, C. Rumpel, G. Guggenberger, and I. K？gel-Knabner, “Stabilization of organic matter by soil minerals-investigations of density and particle-size fractions from two acid forest soils,” Journal of Plant Nutrition and Soil Science, vol. 165, no. 4, pp. 451–459, 2002.
[66]
T. Chevallier, T. Woignier, J. Toucet, E. Blanchart, and P. Dieudonné, “Fractal structure in natural gels: effect on carbon sequestration in volcanic soils,” Journal of Sol-Gel Science and Technology, vol. 48, no. 1-2, pp. 231–238, 2008.
[67]
S. I. Torri and R. S. Lavado, “Dynamics of Cd, Cu and Pb added to soil through different kinds of sewage sludge,” Waste Management, vol. 28, no. 5, pp. 821–832, 2008.
[68]
B. Mackey, I. C. Prentice, W. Steffen et al., “Untangling the confusion around land carbon science and climate change mitigation policy,” Nature Climate Change, vol. 3, no. 6, pp. 552–557, 2013.
[69]
I. K？gel-Knabner, G. Guggenberger, M. Kleber et al., “Organo-mineral associations in temperate soils: integrating biology, mineralogy, and organic matter chemistry,” Journal of Plant Nutrition and Soil Science, vol. 171, no. 1, pp. 61–82, 2008.
[70]
L. C. R. Silva, R. S. Corrêa, T. A. Doane, E. I. P. Pereira, and W. R. Horwath, “Unprecedented carbon accumulation in mined soils: the synergistic effect of resource input and plant species invasion,” Ecological Applicatins, vol. 23, no. 6, pp. 1345–1356, 2013.
[71]
K. C. Haering, W. L. Daniels, and S. E. Feagly, “Reclaiming mined lands with biosolids, manures and papermill sludges,” in Re- Clamation of Drastically Disturbed Lands, R. Barnhisel, Ed., pp. 615–644, Soil Science Society of America, Madison, Wis, USA, 2000.
[72]
P. R. Fresquez and W. C. Lindemann, “Soil and rhizosphere microorganisms in amended coal mine spoils,” Soil Science Society of America Journal, vol. 46, no. 4, pp. 751–755, 1982.
[73]
H. F. Stroo and E. M. Jencks, “Effect of sewage sludge on microbial activity in an old, abandoned minesoil,” Journal of Environmental Quality, vol. 14, no. 3, pp. 301–304, 1985.
[74]
G. Blaga, H. Banescu, L. Stefanescu et al., “Imbunatatirea ferilitatii protsolului antropic de la Capus (jud Cluj) prin utilizarea namolului orasenesc provenit de la statia de epurare a municipiului Cluj-Napoca,” Buletinul Institutului Agronomic Cluj-Napoca. Seria Agricultura si Horticultura, vol. 45, pp. 93–99, 1991.
[75]
K. C. Haering, W. L. Daniels, and J. M. Galbraith, “Appalachian mine soil morphology and properties: effects of weathering and mining method,” Soil Science Society of America Journal, vol. 68, no. 4, pp. 1315–1325, 2004.
[76]
J. A. Baldock and J. O. Skjemstad, “Role of the soil matrix and minerals in protecting natural organic materials against biological attack,” Organic Geochemistry, vol. 31, no. 7-8, pp. 697–710, 2000.
[77]
J. M. Oades, “The retention of organic matter in soils,” Biogeochemistry, vol. 5, no. 1, pp. 35–70, 1988.
[78]
K. L. Sahrawat, “Organic matter accumulation in submerged soils,” Advances in Agronomy, vol. 81, pp. 169–201, 2003.
[79]
G. Séré, C. Schwartz, S. Ouvrard, C. Sauvage, J.-C. Renat, and J. L. Morel, “Soil construction: a step for ecological reclamation of derelict lands,” Journal of Soils and Sediments, vol. 8, no. 2, pp. 130–136, 2008.
[80]
R. K. Shrestha and R. Lal, “Ecosystem carbon budgeting and soil carbon sequestration in reclaimed mine soil,” Environment International, vol. 32, no. 6, pp. 781–796, 2006.
[81]
P. Nannipieri, J. Ascher, M. T. Ceccherini, L. Landi, G. Pietramellara, and G. Renella, “Microbial diversity and soil functions,” European Journal of Soil Science, vol. 54, no. 4, pp. 655–670, 2003.
[82]
N. C. M. Gomes, L. Landi, K. Smalla, P. Nannipieri, P. C. Brookes, and G. Renella, “Effects of Cd- and Zn-enriched sewage sludge on soil bacterial and fungal communities,” Ecotoxicology and Environmental Safety, vol. 73, no. 6, pp. 1255–1263, 2010.
[83]
M. Ros, J. A. Pascual, C. Garcia, M. T. Hernandez, and H. Insam, “Hydrolase activities, microbial biomass and bacterial community in a soil after long-term amendment with different composts,” Soil Biology & Biochemistry, vol. 38, no. 12, pp. 3443–3452, 2006.
[84]
I. Jorge-Mardomingo, P. Soler-Rovira, M. T. Casermeiro, M. T. de la Cruz, and A. Polo, “Seasonal changes in microbial activity in a semiarid soil after application of a high dose of different organic amendments,” Geoderma, vol. 206, pp. 40–48, 2013.
[85]
J. Paz-Ferreiro, G. Gascó, B. Gutiérrez, and A. Méndez, “Soil biochemical activities and the geometric mean of enzyme activities after application of sewage sludge and sewage sludge biochar to soil,” Biology and Fertility of Soils, vol. 48, no. 5, pp. 511–517, 2012.
[86]
E. A. Guertal and B. D. Green, “Evaluation of organic fertilizer sources for south-eastern (USA) turfgrass maintenance,” Acta Agriculturae Scandinavica B, vol. 62, supplement 1, pp. 130–138, 2012.
[87]
G. Renella, A. M. Chaudri, C. M. Falloon, L. Landi, P. Nannipieri, and P. C. Brookes, “Effects of Cd, Zn, or both on soil microbial biomass and activity in a clay loam soil,” Biology and Fertility of Soils, vol. 43, no. 6, pp. 751–758, 2007.
[88]
N. C. M. Gomes, L. Landi, K. Smalla, P. Nannipieri, P. C. Brookes, and G. Renella, “Effects of Cd- and Zn-enriched sewage sludge on soil bacterial and fungal communities,” Ecotoxicology and Environmental Safety, vol. 73, no. 6, pp. 1255–1263, 2010.
[89]
X. Domene, W. Ramírez, S. Mattana, J. M. Alca？iz, and P. Andrés, “Ecological risk assessment of organic waste amendments using the species sensitivity distribution from a soil organisms test battery,” Environmental Pollution, vol. 155, no. 2, pp. 227–236, 2008.
[90]
L. Aldén, F. Demoling, and E. B？？th, “Rapid method of determining factors limiting bacterial growth in soil,” Applied and Environmental Microbiology, vol. 67, no. 4, pp. 1830–1838, 2001.
[91]
C. Palmborg and A. Nordgren, “Partitioning the variation of microbial measurements in forest soils into heavy metal and substrate quality dependent parts by use of near infrared spectroscopy and multivariate statistics,” Soil Biology & Biochemistry, vol. 28, no. 6, pp. 711–720, 1996.
[92]
M. T. Madigan, J. M. Martinko, and J. Parker, Eds., Brock Biology of Microorganisms, Prentice-Hall, Upper Saddle River, NJ, USA, 2000.
[93]
L. Haanstra and P. Doelman, “Glutamic acid decomposition as a sensitive measure of heavy metal pollution in soil,” Soil Biology & Biochemistry, vol. 16, no. 6, pp. 595–600, 1984.
[94]
S. Dahlin, E. Witter, A. M？rtensson, A. Turner, and E. B？？th, “Where's the limit? Changes in the microbiological properties of agricultural soils at low levels of metal contamination,” Soil Biology & Biochemistry, vol. 29, no. 9-10, pp. 1405–1415, 1997.
[95]
S. K. Jones, R. M. Rees, D. Kosmas, B. C. Ball, and U. M. Skiba, “Carbon sequestration in a temperate grassland; management and climatic controls,” Soil Use and Management, vol. 22, no. 2, pp. 132–142, 2006.
[96]
J. M. Soriano-Disla, J. Navarro-Pedre？o, and I. Gómez, “Contribution of a sewage sludge application to the short-term carbon sequestration across a wide range of agricultural soils,” Environmental Earth Sciences, vol. 61, no. 8, pp. 1613–1619, 2010.
[97]
J. W. Dalenberg and G. Jager, “Priming effect of some organic additions to 14C-labelled soil,” Soil Biology & Biochemistry, vol. 21, no. 3, pp. 443–448, 1989.
[98]
G. Renella, L. Landi, F. Valori, and P. Nannipieri, “Microbial and hydrolase activity after release of low molecular weight organic compounds by a model root surface in a clayey and a sandy soil,” Applied Soil Ecology, vol. 36, no. 2-3, pp. 124–129, 2007.
[99]
S. Fontaine, S. Barot, P. Barré, N. Bdioui, B. Mary, and C. Rumpel, “Stability of organic carbon in deep soil layers controlled by fresh carbon supply,” Nature, vol. 450, no. 7167, pp. 277–280, 2007.
[100]
G. Renella, L. Landi, J. Ascher et al., “Long-term effects of aided phytostabilisation of trace elements on microbial biomass and activity, enzyme activities, and composition of microbial community in the Jales contaminated mine spoils,” Environmental Pollution, vol. 152, no. 3, pp. 702–712, 2008.
[101]
P. Rochette and E. G. Gregorich, “Dynamics of soil microbial biomass C, soluble organic C and CO2 evolution after three years of manure application,” Canadian Journal of Soil Science, vol. 78, no. 2, pp. 283–290, 1998.
[102]
S. L. Brown, C. L. Henry, R. Chaney, H. Compton, and P. S. de Volder, “Using municipal biosolids in combination with other residuals to restore metal-contaminated mining areas,” Plant and Soil, vol. 249, no. 1, pp. 203–215, 2003.
[103]
R. G. Burns, “Enzyme activity in soil: location and a possible role in microbial ecology,” Soil Biology & Biochemistry, vol. 14, no. 5, pp. 423–427, 1982.
[104]
G. Renella, L. Landi, and P. Nannipieri, “Hydrolase activities during and after the chloroform fumigation of soil as affected by protease activity,” Soil Biology & Biochemistry, vol. 34, no. 1, pp. 51–60, 2002.
[105]
J. P. Schimel and M. N. Weintraub, “The implications of exoenzyme activity on microbial carbon and nitrogen limitation in soil: a theoretical model,” Soil Biology & Biochemistry, vol. 35, no. 4, pp. 549–563, 2003.
