Sammanfattning

We studied nutrient limitation and availability for soil microbial respiration after additions of glucose (C), in combination with nitrogen (N) and phosphorus (P) in soil samples taken from parklands of Vitellaria paradoxa and Faidherbia albida. We hypothesized that in these P-fixing soils: (i) after C addition, respiration will be limited by P, but P-limitation will be lower under tree canopies; and (ii) the maximum respiration rates after adding C will be higher with than without applications of inorganic fertilizer (NPK) in the field. The study site was located in the south-Sudanese zone of Burkina Faso. Microbial respiration was measured as CO2 evolution from soil samples incubated under laboratory conditions. Two microbial growth peaks were observed after addition of C plus P to the soil samples. When P was added together with C, the initial increase in the microbial respiration rate was higher than when N and C were added, and the maximum respiration rate was also reached earlier. We conclude that P limited the initial rate of respiration. Under the tree canopy the P and N availability, was higher under both F albida and V. paradoxa trees, than in areas beyond their canopies. NPK fertilization in the field resulted in higher soil reserves of N and P, but these nutrients had low availability in the short term. Results indicated that more P is available in forms that are immediately accessible to microorganisms under tree canopies, than outside the cover of their canopies. (c) 2007 Elsevier Ltd. All rights reserved.

Nyckelord

Faidherbia albida; microbial respiration; nitrogen; nutrient limitation; phosphorus; Vitellaria paradoxa

Publicerad i

Soil Biology and Biochemistry
2008, Volym: 40, nummer: 2, sidor: 350-359
Utgivare: PERGAMON-ELSEVIER SCIENCE LTD

SLU författare

• Gnankambary, Zacharia

  • Institutionen för skogens ekologi och skötsel, Sveriges lantbruksuniversitet
    
  • Institute de l'Environnement et des Recherches Agricoles (INERA)

• Ilstedt, Ulrik

  • Institutionen för skogens ekologi och skötsel, Sveriges lantbruksuniversitet
    
  • Center for International Forestry Research (CIFOR)

• Nyberg, Gert

  • Institutionen för skogens ekologi och skötsel, Sveriges lantbruksuniversitet
    

• Malmer, Anders

  • Institutionen för skogens ekologi och skötsel, Sveriges lantbruksuniversitet
    

UKÄ forskningsämne

Skogsvetenskap


Publikationens identifierare

DOI: https://doi.org/10.1016/j.soilbio.2007.08.015

Permanent länk till denna sida (URI)

https://res.slu.se/id/publ/16734