Helmut Dörr
Biographic Data
| ID | 5597553 |
|---|---|
| NAME | Helmut Dörr |
| GIVEN NAMES | Helmut |
| FAMILY NAME | Dörr |
| SIGNATURE | DÖRR H |
| VERIFIED | No |
| TOTAL WORKS | 5 |
| TOTAL CITATIONS | 35 |
| AUTHOR COUNT | 5 |
| EDITOR COUNT | 0 |
| FIRST PUBLICATION YEAR | 1980 |
| LATEST PUBLICATION YEAR | 1996 |
| H-INDEX | 3 |
C Measurements of Soil Organic Matter, Soil Co 2 and Dissolved Organic Carbon (1987–1992)
For several undisturbed sites in Germany, 14 C data are reported for soil organic matter (SOM) (4 sites), soil CO 2 (10 sites) and dissolved organic carbon (DOC) (1 site). With the assumption of a fast degradable component (lifetime ca. 1 yr) and a slow degradable component (lifetime ca. 100 yr), a range between 0.6 and 1.6 mm yr -1 has been determined for the downward migration rates of soil organic carbon at the sampling sites from the soil 14 …
Fast 14C Sample Preparation of Organic Material
A fast 14 C sample preparation technique for organic material in conventional 14 C counting is described. The basic difference from conventional preparation is oxidation of the organic substances in a closed system under an oxygen pressure of ca 10 bars. After the explosion-like combustion, the reaction products SO 2 and NO 2 are oxidized immediately to SO 4 2- and NO 3 − and precipitated on the wall of the reaction vessel. The residual gas mixtu…
Downward Movement of Soil Organic Matter and Its Influence on Trace-Element Transport (210Pb, 137Cs) in the Soil
Data on depth distribution and 14 C content of soil organic carbon, and on soil CO 2 production in forest ecosystems are presented and discussed. Downward movement and turnover of soil organic matter is estimated from a box chain model. The downward transfer velocity of soil organic material depends on the litter material composition and on the annual rate of microbial decomposition. Depth distribution of 210 Pb and 137 Cs was measured. The ident…
Annual Variations of the 14 C Content of Soil CO 2
A 6-year and a 2-year record of 14 C measurements of soil CO 2 in two soils are presented and discussed. The annual 14 C variation of soil CO 2 is controlled by the seasonally varying contribution of root respiration and of microbial decomposition of organic matter producing soil CO 2 . The Δ 14 C soil CO 2 difference between summer and winter is ca 50‰ in a soil where turnover of organic matter is fast (τ = 2.5a) and ca 100‰ in a soil of slow tu…
Carbon-14 and Carbon-13 in Soil Co 2
Carbon isotope measurements in soil CO 2 are presented and discussed. Soil CO 2 concentration and 13 C profiles were measured using a new technique. A simple model describing the CO 2 transport from the soil to the atmosphere is derived. The finding that CO 2 in the soil is richer in 13 C than the CO 2 leaving the soil is attributed to isotopic fractionation in molecular diffusion
Annual Variations of the 14 C Content of Soil CO 2
A 6-year and a 2-year record of 14 C measurements of soil CO 2 in two soils are presented and discussed. The annual 14 C variation of soil CO 2 is controlled by the seasonally varying contribution of root respiration and of microbial decomposition of organic matter producing soil CO 2 . The Δ 14 C soil CO 2 difference between summer and winter is ca 50‰ in a soil where turnover of organic matter is fast (τ = 2.5a) and ca 100‰ in a soil of slow tu…
Carbon-14 and Carbon-13 in Soil Co 2
Carbon isotope measurements in soil CO 2 are presented and discussed. Soil CO 2 concentration and 13 C profiles were measured using a new technique. A simple model describing the CO 2 transport from the soil to the atmosphere is derived. The finding that CO 2 in the soil is richer in 13 C than the CO 2 leaving the soil is attributed to isotopic fractionation in molecular diffusion
Fast 14C Sample Preparation of Organic Material
A fast 14 C sample preparation technique for organic material in conventional 14 C counting is described. The basic difference from conventional preparation is oxidation of the organic substances in a closed system under an oxygen pressure of ca 10 bars. After the explosion-like combustion, the reaction products SO 2 and NO 2 are oxidized immediately to SO 4 2- and NO 3 − and precipitated on the wall of the reaction vessel. The residual gas mixtu…
Downward Movement of Soil Organic Matter and Its Influence on Trace-Element Transport (210Pb, 137Cs) in the Soil
Data on depth distribution and 14 C content of soil organic carbon, and on soil CO 2 production in forest ecosystems are presented and discussed. Downward movement and turnover of soil organic matter is estimated from a box chain model. The downward transfer velocity of soil organic material depends on the litter material composition and on the annual rate of microbial decomposition. Depth distribution of 210 Pb and 137 Cs was measured. The ident…
C Measurements of Soil Organic Matter, Soil Co 2 and Dissolved Organic Carbon (1987–1992)
For several undisturbed sites in Germany, 14 C data are reported for soil organic matter (SOM) (4 sites), soil CO 2 (10 sites) and dissolved organic carbon (DOC) (1 site). With the assumption of a fast degradable component (lifetime ca. 1 yr) and a slow degradable component (lifetime ca. 100 yr), a range between 0.6 and 1.6 mm yr -1 has been determined for the downward migration rates of soil organic carbon at the sampling sites from the soil 14 …
Carbon-14 and Carbon-13 in Soil Co 2
Carbon isotope measurements in soil CO 2 are presented and discussed. Soil CO 2 concentration and 13 C profiles were measured using a new technique. A simple model describing the CO 2 transport from the soil to the atmosphere is derived. The finding that CO 2 in the soil is richer in 13 C than the CO 2 leaving the soil is attributed to isotopic fractionation in molecular diffusion
Annual Variations of the 14 C Content of Soil CO 2
A 6-year and a 2-year record of 14 C measurements of soil CO 2 in two soils are presented and discussed. The annual 14 C variation of soil CO 2 is controlled by the seasonally varying contribution of root respiration and of microbial decomposition of organic matter producing soil CO 2 . The Δ 14 C soil CO 2 difference between summer and winter is ca 50‰ in a soil where turnover of organic matter is fast (τ = 2.5a) and ca 100‰ in a soil of slow tu…
Fast 14C Sample Preparation of Organic Material
A fast 14 C sample preparation technique for organic material in conventional 14 C counting is described. The basic difference from conventional preparation is oxidation of the organic substances in a closed system under an oxygen pressure of ca 10 bars. After the explosion-like combustion, the reaction products SO 2 and NO 2 are oxidized immediately to SO 4 2- and NO 3 − and precipitated on the wall of the reaction vessel. The residual gas mixtu…
Downward Movement of Soil Organic Matter and Its Influence on Trace-Element Transport (210Pb, 137Cs) in the Soil
Data on depth distribution and 14 C content of soil organic carbon, and on soil CO 2 production in forest ecosystems are presented and discussed. Downward movement and turnover of soil organic matter is estimated from a box chain model. The downward transfer velocity of soil organic material depends on the litter material composition and on the annual rate of microbial decomposition. Depth distribution of 210 Pb and 137 Cs was measured. The ident…
C Measurements of Soil Organic Matter, Soil Co 2 and Dissolved Organic Carbon (1987–1992)
For several undisturbed sites in Germany, 14 C data are reported for soil organic matter (SOM) (4 sites), soil CO 2 (10 sites) and dissolved organic carbon (DOC) (1 site). With the assumption of a fast degradable component (lifetime ca. 1 yr) and a slow degradable component (lifetime ca. 100 yr), a range between 0.6 and 1.6 mm yr -1 has been determined for the downward migration rates of soil organic carbon at the sampling sites from the soil 14 …
Chemistry (5 works) · Carbon fibers (4 works) · Environmental Chemistry (4 works) · Environmental Science (4 works) · Soil carbon (4 works) · Soil organic matter (4 works) · Soil Science (4 works) · Soil water (4 works) · Total organic carbon (4 works) · Materials Science (3 works)