Factors influencing the availability of nitrogen in thinned and unthinned Douglas-fir stands in the central Oregon Cascades |
| |
| Institution: | 1. College of Tropical Crops, Hainan University, Haikou, China;2. Department of Biology, University of West Florida, Pensacola, FL, United States;3. School of Geography, Nanjing Normal University, Nanjing, China;1. Department of Environmental Science and Engineering, Huaqiao University, Xiamen 361021, China;2. School of Resources and Environmental Science, Quanzhou Normal University, Quanzhou 362000, China;3. Fujian Provincial Key Laboratory of Ecology-Toxicological Effects & Control for Emerging Contaminants, Putian 351100, China;4. Key Laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, Xiamen, 361021, China |
| |
| Abstract: | Soil N mineralized during 7-day anaerobic incubation at 40°C (‘available’ N) was compared at two soil depths and correlated to soil and site factors in Douglas-fir stands with different combinations of thinning and multinutrient fertilization. Available N expressed either on an area basis (kg ha−1) or on a concentration basis (mg kg−1) at the two depths did not vary significantly by stocking density, treatment, or density-treatment interaction. There was a significant difference between the soil depths, averaging 39 mg kg−1 at 0–20 cm depth, and 20 mg kg−1 at 20–40 cm depth. Available N was positively correlated with total soil N, exchangeable Ca, and adjusted aspect (the former two factors accounting for 46% of the total variation), and negatively with rock content and slope steepness. Stand density had no effect. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
