Many measures have been proposed to mitigate gaseous emissions and other nutrient losses from agroecosystems, which can have large detrimental effects for the quality of soils, water and air, and contribute to eutrophication and global warming. Due to complexities in farm management, biological interactions and emission measurements, most experiments focus on analysis of short-term effects of i...

One of the major challenges for agriculture is to understand the effects of agricultural practices on soil properties and diffuse pollution, to support practical farm-scale land management. Three conventionally managed grassland fields with similar short-term management, but different ploughing histories, were studied on a long-term research platform: the North Wyke Farm Platform. The aims were...

1. Most plants withdraw nutrients from leaves as they age, and redeploy them elsewhere in the plant. The proportion of nutrients resorbed and the residual nutrient concentration in senesced leaves are different but complementary indices of nutrient conservation via this process. A major spectrum of strategic variation runs from plant species with typically long leaf lifespan (LL), high leaf mas...

Important due to both its role in fire-affected ecosystems, and also its proposed intentional production and application for carbon (C) management, pyrogenic organic matter (PyOM) is thought to contain very stable forms of C. However, the mechanisms behind its interactions with non-PyOM soil organic C (SOC) remain speculative, with studies often showing short-term positive and then long-term ne...

Growing concern about water quality issues, along with a series of fish kills in 1997, prompted Maryland, Delaware, and Virginia to adopt regulations to reduce nutrient pollution from agricultural nonpoint sources. All three states required farmers to follow a state-certified nutrient management plan that would "optimize crop yields and minimize environmental losses," although the policy-making...

Factors affecting water and nutrient outflow beyond the rooting zone were studied during a 3-yr period, using data from eight contrasting stands of lodgepole pine (Pinus contorta ssp. latifolia) forest in southeastern Wyoming and the output of a hydrologic simulation model (H20TRANS) based on tree physiology. Nutrient outflow during a specific time period was estimated by multiplying simulated ...