Open AccessEffects of soil properties and organic residues management on C sequestration and N losses
Author(s) -
Asher BarTal,
Paul R. Bloom,
Pinchas Fine,
C. E. Clapp,
A. Hadas,
Rodney T. Venterea,
D. Zohar,
Changyin Dong,
J. A. E. Molina
Publication year - 2008
Language(s) - English
Resource type - Reports
DOI - 10.32747/2008.7587729.bard
Subject(s) - mineralization (soil science) , soil water , calcareous , leaching (pedology) , soil organic matter , decomposition , organic matter , environmental chemistry , environmental science , soil carbon , carbon sequestration , chemistry , soil science , nitrogen , bulk soil , geology , paleontology , organic chemistry
Objectives - The overall objective of this proposal was to explore the effects of soil properties and management practices on C sequestration in soils and off-site losses of N.The specific objectives were: 1. to investigate and to quantify the effects of soil properties on C transformations that follow OW decomposition, C losses by gaseous emission, and its sequestration by organic and mineral components of the soil; 2. to investigate and to quantify the effects of soil properties on organic N mineralization and transformations in soil, its losses by leaching and gaseous emission; 3. to investigate and to quantify the effects of management practices and plants root activity and decomposition on C and N transformations; and 4. to upgrade the models NCSOIL and NCSWAP to include inorganic C and root exudation dynamics. The last objective has not been fulfilled due to difficulties in experimentally quantification of the effects of soil inorganic component on root exudation dynamics. Objective 4 was modified to explore the ability of NCSOIL to simulate organic matter decomposition and N transformations in non- and calcareous soils. Background - Rates of decomposition of organic plant residues or organic manures in soil determine the amount of carbon (C), which is mineralized and released as CO₂ versus the amount of C that is retained in soil organic matter (SOM). Decomposition rates also greatly influence the amount of nitrogen (N) which becomes available for plant uptake, is leached from the soil or lost as gaseous emission, versus that which is retained in SOM. Microbial decomposition of residues in soil is strongly influenced by soil management as well as soil chemical and physical properties and also by plant roots via the processes of mineral N uptake, respiration, exudation and decay.