What is soil compaction?

Canadian Society of Soil Science's avatarGrounded in Soils

A healthy soil is a mixture of soil particles, air and liquid. Air and liquid take up space in the area that is called a soil pore. When soil is subjected to pressure, it tends to compress – called soil compaction. The main effect this has on soil reducing the pore space between soil particles. Pores contain vital air and liquids for plants and soil microbes.

The pressure can come from a footprint or tractor wheels. In healthy soils, this air provides needed oxygen to soil microbes and plant roots. When soil is compacted, there is less air – and thus less oxygen for microbes, roots, etc. In addition, in soils with less pore space, water has no path to flow down into the soil.

Compaction in agriculture and forestry

A major cause of man-made compaction in agriculture is related to the use of heavy machinery. For example, as…

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GPS Error

Beards and Triathlons's avatarBeards and Triathlons

You might have noticed some GPS drift on your activities in the last few weeks, or even a run that was way off course. It happened to me a few times, as you can see below.

The walk above wasn’t too far off course, but a couple of other activities were far more wrong. This has occurred with fairly new watches from Garmin, Suunto and Polar, and is all to do with the GPS chip made by Sony.

Every few days a file is sent to the various Apps, which is then sent to your watch. This file contains details of where the satellites will be over the next few days, allowing your watch to find GPS reception much quicker. Quite clever when you think about it.

However, this file has been wrong a couple of times, hence why there has been GPS drift. Garmin have assured everyone that the…

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THE BIRHOR ( BIHUL ) TRIBE : A HISTORY & CULTURE

ARBIND KUMAR's avatarARBIND KUMAR BLOG

When I was posted in the West Shinghbhum district ( now in the state of Jharkhand ) in late nineties , I heard the name of an aboriginal tribe called BIRHOR . Their actions appeared little peculiar to me because they preferred to live in the hut made up of bamboos and dry vines and herbs of the forest despite the fact that the Government had built pacca shelters for each family of the tribe . They were scattered in the areas of Sonua , Goerkera , Chota Nagara , Bada Nagara ( mostly in the forest areas of Saranda ) in Jharkhand and in some parts of West Bengal , Orisha , Chhatisgarh and Bihar . Traditionally nomadic , speaking Birhor language , the BIRHOR tribe has population of about 10726 in the state of Jharkhand , about 3104 in the state of Chhatisgarh , about 2241 in the…

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Southeast Asia Historical Maps

Mercator, Insulæ Indiæ orientalis præcipuæ, 1606.The Digital Historical Maps of Singapore and Southeast Asia project, hosted by (the soon-to-be-defunct) Yale-NUS College in Singapore, curates a collection of pre-1900 maps of southeast Asia. The maps are drawn from the Bodleian, Beinecke and Leiden libraries, as well as Singapore’s National Library Board. [Maps Mania]

Southeast Asia Historical Maps — The Map Room
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