Root respiration of Douglas-fir seedlings: effects of N concentration
Lu, S; Mattson, KG; Zaerr, JB; Marshall, D
| HERO ID | 93028 |
|---|---|
| In Press | No |
| Year | 1998 |
| Title | Root respiration of Douglas-fir seedlings: effects of N concentration |
| Authors | Lu, S; Mattson, KG; Zaerr, JB; Marshall, D |
| Journal | Soil Biology and Biochemistry |
| Volume | 30 |
| Issue | 3 |
| Page Numbers | 331-336 |
| Abstract | Six-month-old Douglas-fir [Pseudotsuga menziesii (Mirb.) Franco] seedlings were grown at three N concentrations and with controlled root temperatures. Measurements of root respiration were conducted on undisturbed root systems by passing humidified air with 1000 Ál l-1 CO2 through root boxes onto an infrared gas analyzer. The objective was to understand the effects of N on soil respiration by examining total root respiration rate per seedling, specific root respiration rate g-1 root dry wt, and root dry wt after N fertilization. Total respiration rates of seedlings grown at 50 mg l-1 N concentration were significantly higher than those grown at 10 mg l-1 or 200 mg l-1 N concentration. Seedlings grown at N concentration of 200 mg l-1 had significantly smaller roots than those grown at the two lower N concentrations. The specific respiration rate increased as N concentration was increased from 10 to 50 mg l-1 N concentration, but remained constant as N was further increased from 50 to 200 mg l-1. The increase of total respiration rate with the increase in N concentration from 10 to 50 mg l-1 was attributed to the increase in specific respiration, whereas the subsequent decrease in total respiration with the increase in N concentration from 50 to 200 mg l-1 was attributed to the decrease in root dry wt. The depression of soil respiration after the addition of N fertilizers to relatively fertile soil may be explained by reduced root and mycorrhizal mycelial growth. |
| Doi | 10.1016/S0038-0717(97)00134-X |
| Wosid | WOS:000072509400007 |
| Url | http://linkinghub.elsevier.com/retrieve/pii/S003807179700134X |
| Is Certified Translation | No |
| Dupe Override | No |
| Comments | ECRIB.Root respiration of Douglas-fir seedlings: effects of N concentration.Soil Biol. Biochem. 30: 331-336. |
| Is Public | Yes |
| Is Qa | No |