An analysis of the effects of frosts on the principal coffee areas of Brazil

Frost damage on coffee plantations in south-central Brazil is not a frequent occurrence. However, when this area is affected by a severe frost — as happened in August of 1975 — the consequences for the agricultural economy of south-central Brazil and the socio-economic condition of the rural labourers are serious.In this paper the meteorological characteristics of a frost condition are outlined and their physiological effects upon coffee bushes are stated. A differentiation is made as to the timely occurrence of frosts and their effects on crops. If the frost hits during harvest time (April through June) the beans may be burned and a qualitative loss may ensure. If the frost occurs after the harvest, only the coffee bushes are affected and they may have recovered by the following agricultural year. The most devastating frosts are those that occur late in winter (August-September) because they kill the buds and the flowers so that next year's harvest will be lost.Coffee in south-central Brazil is usually grown on plantations of 10 to 100 ha, and 100 to 1000 ha. There has been a trend to expand the coffee growing area into Mato Grosso-Rondonia, while in the state of Parana, where frosts are more severe but the soils are better, coffee growing in large estates has intensified. Moreover, the introduction of new methods of planting and mechanization of the agricultural work have brought about an intensification of coffee production. Analysis of the improvements in cultivating pratices and of agricultural mechanization that these two processes have caused a drastic reduction in the demand for agricultural labourers. Added to this, the possibilities of rural employment have also been adversely affected by the trend among many coffee growers to introduce other crops into their estates in order to minimize their losses due to frost.     

Interpretation of landslide distribution triggered by the 2005 Northern Pakistan earthquake using SPOT 5 imagery

The 2005 northern Pakistan earthquake (magnitude 7.6) of 8 October 2005 occurred in the northwestern part of the Himalayas. We interpreted landslides triggered by the earthquake using black-and-white 2.5-m-resolution System Pour l’Observation de la Terre 5 (SPOT 5) stereo images. As a result, the counts of 2,424 landslides were identified in the study area of 55 by 51 km. About 79% or 1,925 of the landslides were small (less than 0.5 ha in area), whereas 207 of the landslides (about 9%) were large (1 ha and more in area). Judging from our field survey, most of the small landslides are shallow rock falls and slides. However, the resolution and whitish image in the photos prevented interpreting the movement type and geomorphologic features of the landslide sites in detail. It is known that this earthquake took place along preexisting active reverse faults. The landslide distribution was mapped and superimposed on the crustal deformation detected by the environmental satellite/synthetic aperture radar (SAR) data, active faults map, geological map, and shuttle radar topography mission data. The landslide distribution showed the following characteristics: (1) Most of the landslides occurred on the hanging-wall side of the Balakot–Garhi fault; (2) greater than one third of the landslides occurred within 1 km from the active fault; (3) the greatest number of landslides (1,147 counts), landslide density (3.2 counts/km²), and landslide area ratio (2.3 ha/km²) was found within Miocene sandstone and siltstone, Precambrian schist and quartzite, and Eocene and Paleocene limestone and shale, respectively; (4) there was a slight trend that large landslides occurred on vertically convex slopes rather than on concave slopes; furthermore, large landslides occurred on steeper (30° and more) slopes than on gentler slopes; (5) many large landslides occurred on slopes facing S and SW directions, which is consistent with SAR-detected horizontal dominant direction of crustal deformation on the hanging wall.