community collected shade tree leaves was determined ( Heckman and Kluchinski 1996 ). The laboratory analysis ( Table 1 ) reveals that the material typically has 50 parts carbon (C) to 1 part N. Knowing this ratio is key to understanding how readily a plant
, synthetic sources of nitrogen (fixed by the Haber–Bosch process) are energy intensive to produce, prohibited by agencies that certify organic practices, and do not provide a source of carbon to build soil OM ( Crews and Peoples, 2004 ). The use of composts
residues that are low carbon/nitrogen, but even modest gains in SOM in these soils markedly improves cation exchange capability, nutrient cycling, and nutrient availability. Annual rates of SOM decomposition in most soils do not exceed 2% to 5% ( Paul and
lamps from 0600 hr to 2000 hr daily. Cation exchange capacity, carbon-to-nitrogen ratio, particle size distribution, and bulk density. Cation exchange capacity, C:N ratio, particle size distribution, and BD were determined for five treatments: non
stems and coarse roots and accumulated N in fine roots and accumulated C in old stems. Fig. 2. Nitrogen (N) concentration and carbon to N (C/N) ratio in current-year (2006) stems of green ash trees grown with different rates of N from two types of
carbon-to-nitrogen (C/N) ratio of 15.06. Commercial sphagnum peat, perlite, and vermiculite were donated by Fafard, Inc. (Apopka, FL). The sphagnum peat was from Canada, designated as Canadian peat; it had a pH of 3.9, an EC 0.32 dS·m −1 , and a C/N ratio
, and it is also an important factor to improve yield and quality of tea ( Ruan et al., 2001 ). Nitrogen, either from organic or mineral fertilization, plays an important role in the growth and development of tea tree. Meanwhile, it is an important
. ( B ) Regression for layer depth versus carbon ( C )-to-N ratio. Carbon-to-N ratio = 39.42 – 3.28 × layer, R 2 = 0.44, P < 0.0001. Values based on mean ± se . Lines only shown for significant regressions ( P ≤ 0.05). Discussion
contrast to total N content, in our 15 N tracer uptake observations, the aboveground tissue 15 N enrichment was greater in PreHerb trees than Sod or Mulch trees, except for trunk and scaffold biomass ( Fig. 7A ). For belowground tissues, the δ 15 N ratios
study. These details were provided by B. Flanner (personal communication). Table 2. Total nitrogen (N) content and carbon-to-nitrogen (C:N) ratio of the organic N input additions and the substrate ( control ), along with the amount of N applied via the N