Subsurface drip irrigation emitter spacing effects on soil water redistribution, corn yield and water productivity

Emitter spacings of 0.3 to 0.6 m are commonly used for subsurface drip irrigation (SDI) of corn on the deep, silt loam soils of the U.S. Great Plains. Subsurface drip irrigation emitter spacings of 0.3, 0.6, 0.9 and 1.2 m were examined for the resulting differences in soil water redistribution, corn grain yield, yield components, seasonal water use, and water productivity in a 4‐year field study (2005 through 2008) at the Kansas State University Northwest Research‐Extension Center, Colby, Kansas. The results indicate that there is increased preferential water movement along the dripline (parallel) as compared to perpendicular to the dripline and that this phenomenon partially compensates for wider emitter spacings in terms of soil water redistribution. Corn yield and water productivity (WP) were not significantly affected by the emitter spacing with application of a full irrigation regime

Surveillance and data retention in Poland

The object of analysis in the present text is the issue of operational control and data retention in Poland. The analysis of this issue follows from a critical stance taken by NGOs and state institutions on the scope of operational control wielded by the Polish police and special services – it concerns, in particular, the employment of “itemized phone bills and the so-called phone tapping.” Besides the quantitative analysis of operational control and the scope of data retention, the text features the conclusions of the Human Rights Defender referred to the Constitutional Tribunal in 2011. It must be noted that the main problems concerned with the employment of operational control and data retention are caused by: (1) a lack of specification of technical means which can be used by individual services; (2) a lack of specification of what kind of information and evidence is in question; (3) an open catalogue of information and evidence which can be clandestinely acquired in an operational mode. Furthermore, with regard to the access granted to teleinformation data by the Telecommunications Act, attention should be drawn to a wide array of data submitted to particular services. Also, the text draws on the so-called open interviews conducted mainly with former police officers with a view to pointing to some non-formal reasons for “phone tapping” in Poland. This comes in the form of a summary.