Organic C levels of Ap horizons in North German Pleistocene sands as influenced by climate, texture, and history of land-use
- authored by
- Günther Springob, Sven Brinkmann, Nicole Engel, Holger Kirchmann, Jürgen Böttcher
- Abstract
We evaluated the contents of organic carbon (Corg) of Ap horizons from 11 North German study areas along a Southeast to Northwest precipitation gradient with respect to their general levels and as related to C : N ratio, soil texture (clay content), bulk soil density, climate, and historical land-use since 1780. The focus was on sandy soils, with the largest group of samples originating from 308 km2 of the Fuhrberg catchment north of Hannover/Lower Saxony. Data from loess areas were used for comparisons. Major aims were (1) to quantify current Corg stocks, (2) to provide data on site-specific, steady-state Corg levels in old arable soils, and (3) to identify the main controls of Corg levels in the studied sands. The mean Corg content in sandy, well-drained, old Ap horizons (uplands, > 200 years under cultivation, near steady-state) increased with precipitation from < 8 g kg-1 in the dry eastern parts of the study area (530 mm year 1, 8.3°C) to 25 g kg-1 in the moist Northwest (825 mm year-1, 8.4°C). The Corg levels in lowlands which have been drained for more than 40 years were approximately 3 g kg-1 higher than those of uplands under a similar climate. The factor clay content had no predictive value because low contents were associated with high Corg levels. Large proportions of refractory organic matter in sands resulting from specific features of historical land-use and soil development (calluna heathland, heath plaggen fertilization, podzolization) appeared to be the most probable reason for such high Corg levels. However, the high Corg levels of these old arable sites were still exceeded by those of younger arable areas formerly under continues grassland. A chrono-sequence suggested that a period of about 100 years is necessary until a new steady-state Corg level is established after conversion of grassland into arable land. Elevated Corg levels in current Ap horizons were also found for former woodland and heathland soils. The main conclusion is that sands can contain a lot of stable organic matter, sometimes more than finer textured soils.
- Organisation(s)
-
Institute of Soil Science
Section Soil Biophysics
- External Organisation(s)
-
State Authority for Mining, Energy and Geology (LBEG)
Swedish University of Agricultural Sciences
- Type
- Article
- Journal
- Journal of Plant Nutrition and Soil Science
- Volume
- 164
- Pages
- 681-690
- No. of pages
- 10
- ISSN
- 1436-8730
- Publication date
- 12.2001
- Publication status
- Published
- Peer reviewed
- Yes
- ASJC Scopus subject areas
- Soil Science, Plant Science
- Sustainable Development Goals
- SDG 13 - Climate Action, SDG 15 - Life on Land
- Electronic version(s)
-
https://doi.org/10.1002/1522-2624(200112)164:6<681::AID-JPLN681>3.0.CO;2-V (Access:
Unknown)