Feature Article

Conservation agriculture (CA) is an agricultural management practice in which there is minimum soil disturbance, retention of residue for soil cover and rotation of major crops. In contrast, soil in traditional agriculture is intensively tilled to prepare a fine and well-pulverized seedbed. Soil tillage or land preparation is the most energy-consuming operation among all field operations. Compared to traditional agriculture, farmers can save up to 40% of time, labour and fuels in CA.

At the turn of the century and the millennium, Science carried a series of essays titled Pathways of Discovery. An extremely readable and characteristically eloquent essay on Infectious History still holds a place, albeit indistinct and receding, in my memory. The author, Joshua Lederberg, was one of the most influential figures of 20th century biology and a writer of rare scholarship. In his essay, Lederberg traces the history of the relationships between men and microbes; a long history of

“Science-based” standards are an integral part of modern regulatory systems. Studies on “public understanding of science” mostly focus on high technology areas in advanced economies. In contrast, the present study analyses the public understanding of regulation in the context of standard-setting for bottled water quality in India. Using primary data, the econometric models of this paper show that public understanding of participation in regulation depends on awareness of, and trust in, existing regulatory practices in a complex, non-linear manner.

We investigated if elevated CO2 could alleviate the negative effect of high temperature on fruit yield of strawberry (Fragaria × ananassa Duch. cv. Toyonoka) at different levels of nitrogen and also tested the combined effects of CO2, temperature and nitrogen on fruit quality of plants cultivated in controlled growth chambers. Results show that elevated CO2 and high temperature caused a further 12% and 35% decrease in fruit yield at low and high nitrogen, respectively.

A recent study by Feng et al. [Feng S, Krueger A, Oppenheimer M (2010) Proc Natl Acad Sci USA 107:14257–14262] in PNAS reported statistical evidence of a weather-driven causal effect of crop yields on human migration from Mexico to the United States. We show that this conclusion is based on a different statistical model than the one stated in the paper. When we correct for this mistake, there is no evidence of a causal link.

The debate surrounding the safety of shale gas development in the Appalachian Basin has generated increased awareness of drinking water quality in rural communities. Concerns include the potential for migration of stray gas, metal-rich formation brines, and hydraulic fracturing and/or flowback fluids to drinking water aquifers. A critical question common to these environmental risks is the hydraulic connectivity between the shale gas formations and the overlying shallow drinking water aquifers.

The Greenland GPS Network (GNET) uses the Global Positioning System (GPS) to measure the displacement of bedrock exposed near the margins of the Greenland ice sheet. The entire network is uplifting in response to past and present-day changes in ice mass. Crustal displacement is largely accounted for by an annual oscillation superimposed on a sustained trend. The oscillation is driven by earth’s elastic response to seasonal variations in ice mass and air mass (i.e., atmospheric pressure).

Limitations in current capabilities to constrain aerosols adversely impact atmospheric simulations. Typically, aerosol burdens within models are constrained employing satellite aerosol optical properties, which are not available under cloudy conditions. Here we set the first steps to overcome the long-standing limitation that aerosols cannot be constrained using satellite remote sensing under cloudy conditions. We introduce a unique data assimilation method that uses cloud droplet number (Nd) retrievals to improve predicted below-cloud aerosol mass and number concentrations.

The aim of this study was to determine response patterns and mechanisms of soil respiration to precipitation increases in subtropical regions.