Xem 1-20 trên 133 kết quả Erosion
  • The book deals with several aspects of soil erosion, focusing on its connection with the agricultural world. Chapters' topics are various, ranging from irrigation practices to soil nutrient, land use changes or tillage methodologies. The book is subdivided into fourteen chapters, sorted in four sections, grouping different facets of the topic: introductive case studies, erosion management in vineyards, soil erosion issue in dry environments, and erosion control practices.

    pdf346p cucdai_1 15-10-2012 54 20   Download

  • Soil erosion affects a large part of the Earth surface, and it represents one of the most relevant environmental problems worldwide. Intense land degradation processes that destroyed civilizations in the past are still going on at present. Accelerated soil erosion is one of the main soil threats, as the natural balance between soil formation and loss may be seriously compromised, leading to desertification and permanent loss of fertility and protective function. Soil erosion is not only related to agricultural activities and farming practices, but also to land management in general....

    pdf332p cucdai_1 14-10-2012 57 14   Download

  • Soil erosion is a hazard traditionally associated with agriculture in tropical and semi-arid areas and is important for its long-term effects on soil productivity and sustainable agriculture. It is, however, a problem of wider significance occurring additionally on land devoted to forestry, transport and recreation. Erosion also leads to environmental damage through sedimentation, pollution and increased flooding. The costs associated with the movement and deposition of sediment in the landscape frequently outweigh those arising from the long-term loss of soil in eroding fields.

    pdf316p coeus75 29-01-2013 31 10   Download

  • Soil loss for erosion is a natural phenomenon in soil dynamics, influenced by climate, soil intrinsic properties, and morphology, that can both trigger and enhance the process. Anthropic activities, like inappropriate agricultural practices, deforestation, overgrazing, forest fires and construction activities, may exert a remarkable impact on erosion processes or, on the other hand, contribute to soil erosion mitigation through a sustainable management of natural resources.

    pdf200p camchuong_1 04-12-2012 38 8   Download

  • Toe erosion, especially in stormy conditions, is one of the common mechanism causing the failure and instability of the sea dikes and revetments. The erosion intensity becomes more serious at the beaches which is under the impacts of typhoons. Reliable forecasts about the intensity of toe erosion of sea dikes in stormy conditions have important ecnomomic and technical meaning in the design and construction of sea dikes.

    pdf9p tinhluong123 21-11-2015 19 3   Download

  • Haiphong is a major industrial and port city in Vietnam. It plays an important role in the coastal shipping routes in the northern part of Vietnam. In recent years, the eposition and erosion of the coastal zone of Haiphong has increased in terms of intensity and scale, which has seriously influenced the socialeconomic activities of the area.

    pdf8p tinhluong123 21-11-2015 12 2   Download

  • In the paper, the primarily results of the above mentioned simulations (as waves, currents, sediments transports and bottom - coastal lines evolution) has been shown. Based on the obtained results, there is a strong correlation between the protrusion magnitude and the southward moving of the erosion areas.

    pdf12p thienthanquydu 21-10-2018 0 0   Download

  • Agrodok 11 Erosion control in the tropics Hil Kuypers Anne Mollema Egger Topper Agromisa Foundation, Wageningen, 2005. All rights reserved. No part of this book may be reproduced in any form, by print, photocopy, microfilm or any other means, without written permission from the publisher.

    pdf9p trasua1 24-09-2010 72 12   Download

  • 2 How to recognize erosion The previous chapter explained how erosion can impede development of large areas and even whole countries. Now an attempt will be made to illustrate the ways in which a farmer is confronted with the physical characteristics of erosion in the daily work.

    pdf7p trasua1 24-09-2010 57 8   Download

  • The papers in this book provide new information on several aspects of soil erosion and applications of the National Resources Inventory (NRI). They were commissioned following a planning workshop in July 1984 and were presented in December 1984 during a national convocation, “Physical Dimensions of the Erosion Problem.” The workshop and convocation were held by the National Research Council's Board on Agriculture in response to a request from the Soil Conservation Service of the U.S.

    pdf327p coeus75 29-01-2013 25 8   Download

  • 3 The erosion process Some understanding of the way in which the erosion process takes place is needed to appreciate the usefulness of preventive measures. A few factors will be mentioned which together determine how much and what type of erosion is likely to occur.

    pdf9p trasua1 24-09-2010 48 7   Download

  • 4 How erosion effects agriculture In Chapter 2 a few examples have been given as to how erosion can be observed in the field. Sooner or later, all the changes observed have consequences for agriculture. To mention one example: small rills, unlike gullies, can still be ploughed by the farmer.

    pdf4p trasua1 24-09-2010 57 7   Download

  • 5 Agronomic methods to control erosion Agronomic methods include those erosion control measures that are related to arable farming. It is concerned with crop cultivation itself as well as tillage operations. Arable farming is an integral part of the natural surroundings.

    pdf18p trasua1 24-09-2010 53 7   Download

  • 6 Using cropping systems to control erosion Rotation and fallow Many tropical farming systems have originated from shifting cultivation; a system of food production based on a rotation of cultivation followed by a long fallow period. The fallow period ensures a natural recovery of soil fertility.

    pdf8p trasua1 24-09-2010 56 7   Download

  • 8 Underlying causes of erosion In the previous chapters we have seen how the chance of erosion can be lessened by taking certain precautions. However, circumstances are sometimes such that a farmer cannot adopt another method of production that would be less damaging.

    pdf2p trasua1 24-09-2010 63 7   Download

  • 9 Conditions for the success of operations Erosion control will have the best chance of success if the underlying causes are removed. Unfortunately this is not always within reach of the farmer concerned or the well-intentioned development worker either.

    pdf4p trasua1 24-09-2010 51 7   Download

  • 7 Measures to reduce runoff Often technical measures against erosion are not very beneficial in themselves. They should go hand in hand with cultivation methods and good guidance. An important question is whether the farmer himself can pay for the operations and/or execute them.

    pdf17p trasua1 24-09-2010 40 6   Download

  • 10 Conclusion After reading this booklet you will probably be feeling confused by all the different ways to control erosion and what it entails. Perhaps you would have preferred some concrete advice; now you can’t see the wood for the trees! Yet you will appreciate that we cannot give concrete advice to start you off because the situations

    pdf19p trasua1 24-09-2010 42 6   Download

  • The mountainous area occupies three fourth of the total area of Binh Dinh Province. The potential of landuse is very large. However, under the influence of irrational exploitation and natural disasters in the past, the land resource has declined, thus leading to the decline of forest resource. Furthermore, the increase of unused land and bare hills along with the decrease in the cultivated area seriously influenced on the ecological environment as well as the socio-economic development.

    pdf8p dem_thanh 22-12-2012 33 5   Download

  • Tuyển tập các báo cáo nghiên cứu về y học được đăng trên tạp chí y học General Psychiatry cung cấp cho các bạn kiến thức về ngành y đề tài: A combination of methotrexate and zoledronic acid prevents bone erosions and systemic bone mass loss in collagen induced arthritis...

    pdf10p thulanh14 19-10-2011 23 4   Download


Đồng bộ tài khoản