Effects of climate change on nitrogen dynamics in upland soils. 1. A transplant approach

Abstract

The impact of climate change on N leaching from hill land plant/soil systems was investigated using a transplant technique involving the movement of intact lysimeter cores of three contrasting soil types down an altitudinal gradient at Great Dun Fell, Cumbria. Air and soil temperatures and precipitation were monitored at four elevations down an altitudinal transect using automatic weather stations for a period of two years. The altitudinal sequence of air temperature followed the anticipated pattern, providing mean annual temperatures at the four locations of 3.4, 5.0, 6.3 and 8.1 °C. Lapse rates of both mean air and soil temperatures over the altitudinal range 171–845 m were 6.6 (1993) and 7.0 °C km–1 (1994). Soil monthly temperature gradients for a particular soil type for each of the two years showed a seasonal range of 6.0 and 7.4 °C km–1, respectively, and for air temperature of 4.3 and 3.1 °C km–1. Precipitation gradients showed the expected general increase with altitude, but were less predictable. Inorganic nitrogen leaching was studied in lysimeter leachates with climatic amelioration resulting in dramatic reductions in leachate nitrate concentrations and associated total concentrations of inorganic nitrogen. Decreases in leachate nitrate concentrations were observed for all three soil types studied. Soils receiving supplemented rainfall also showed decreased N concentrations, suggesting that temperature was the main controlling factor responsible for the observed reductions. Increased N uptake by the vegetation, in response to the increases in temperature, is considered to be critical in controlling soil solution chemistry at these sites.

Impacts of altitude and position on the rates of soil nitrogen mineralization and nitrification in alpine meadows on the eastern Qinghai–Tibetan Plateau, China

“…Soil properties with altitude and position By increasing altitude temperature will typically decrease and the corresponding precipitation will increase (Barry 1981;Ineson et al 1998), thus directional positions are a main factor for the differences in climate distribution. The SF slope was warmer/drier than the NF slope due to differences in micrometeorological conditions (Du et al 2003).…”

Future consequences and challenges for dairy cow production systems arising from climate change in Central Europe – a review

“…In pure grass stands, nitrogen fertilizer additions would be more effective in terms of productivity. At the same time, increased temperatures may accelerate soil processes such as mineralization, leading to a more rapid supply of nutrients from decomposing organic material if sufficient water is available, but potentially also larger leaching losses of mobile nutrients (Ineson et al, 1998a and1998b;Niklaus et al, 2006;Sardans et al, 2006). Increased CO 2 atmospheric concentrations together with nitrogen fertilization have been found to accelerate flowering in forbs, but delay in that of grasses, decreasing phenological complementarity (Cleland et al, 2006).…”

“…Increasing CO 2 concentrations have been shown to increase nitrogen limitation of grass production (Lü scher et al, 2005). This would be beneficial for the competitiveness and growth et al, 1998a and1998b;Niklaus et al, 2006;Sardans et al, 2006). Increased CO 2 atmospheric concentrations together with nitrogen fertilization have been found to accelerate flowering in forbs, but delay in that of grasses, decreasing phenological complementarity (Cleland et al, 2006).…”

A review of the impact of climate change on future nitrate concentrations in groundwater of the UK

“…N mineralisation and nitrification are related to temperature and indirectly to rainfall (Emmett et al, 2004). The overall effects depend on how changes affect soil moisture during the summer season (Leirós et al, 1999), on the countering effects of growth enhancement from increased carbon inputs and increased nitrate uptake by vegetation (Ineson et al, 1998a;Ineson et al, 1998b).…”