Soil and water conservation engineering
The lower rainfall in semi-arid areas compared with that in humid climates does not mean a corresponding low level of soil erosion by water. Indeed rainfall erosion can be higher in semi-arid areas than in any other climatic zone. This is partly because the rainfall of semi-arid areas has a high proportion of convective thunderstorm rain of high intensity and high erosive power.
It is also because there is poor protective vegetative cover, especially at the beginning of the rainy season. Some of the soils common in semi-arid areas are particularly vulnerable, either because they have poor resistance to erosion high erodibilityor because of their chemical and physical properties. An example from Mexico is illustrated in Plate 4.
Successful but expensive gully conservation like the Australian example shown in Plate 4. There are always strong links between measures for soil conservation and measures for water conservation, and this applies equally in semi-arid areas. Many measures are directed primarily to one or the other, but most contain an element of both. Reduction of surface run-off by structures or by changes in land management will also help to reduce erosion.
Similarly, reducing erosion will usually involve preventing splash erosion, or formation of crusts, or breakdown of structure, all of which will increase infiltration, and so help the water conservation.
The approach by soil conservationists in the s is moving away from using mechanical works and structures in soil conservation programmes paid for by a government or a donor-funded project.
An example is the increasing awareness of the ineffectiveness of terracing programmes alone. Also, we are moving towards the view that the only effective programmes are those which have the full support of the people. The subsistence farmer cannot afford to respond to philosophical or emotional appeals to care for the soil, and this means that conservation measures must have visible short-term benefits to the farmer.
For the subsistence farmer the benefit he would most appreciate might be increased yields per unit of land, or perhaps better production per unit of labour, or perhaps improved reliabi- lity of yield.
The idea of working together in groups on tasks which require a big labour force is well-established in many countries, particularly for planting or harvesting. The practice can be successfully extended to conservation works. If we accept the argument that soil conservation must be cost- effective to be acceptable to the farmer, then the low value of production from semi-arid soils means that only cheap and simple solutions are appro- priate.
On a fertile soil with good rainfall it may be sensible to invest a lot of labour or money in sophisticated schemes for controlling the run- off, but not in semi-arid areas with low and unreliable yields. It follows that attempts to eliminate soil erosion completely may be unrealistic, and that some level of erosion may have to be accepted, and also some risk' of soil conservation measures failing. An example of a realistic approach to the risk of failure are the flood diversion dams built in the People's Democratic Republic of Yemen for spate irrigation schemes.
Each end of the diversion is built of stone, or nowadays concrete, with a simple earth centre section. It is accepted that the earth section will be destroyed by big floods but it is cheap to repair or replace Thomas To upgrade the design and construction so that they could withstand the year flood would increase the construction effort beyond what the farmers can provide.
This same approach should be applied to all mechanical conservation programmes in semi-arid areas. Many conservation programmes have failed because the technology was inappropraite, or misapplied, or because they did not take account of the social situation and did not involve the people.
The record of soil conservation in north Africa is striking. Heusch concludes that the large conservation programmes in Algeria, Morocco and Tunisia, from towere based on inappropriate technology imported from the totally different conditions of the United States, and the whole effort was a mistake which should not be repeated. This umbrella term can include reduced tillage, minimum tillage, no-till, direct drill, mulch tillage, stubble-mulch farming, trash farming, strip tillage, plough-plant for details see Mannering and Fenster In countries with advanced soil conservation programmes, particularly the USA and Australia, the concept of conservation tillage is the main theme of the recommendations for cropland, and it is also being taken up quickly in other areas, for example southern Brazil.
The application is mainly in mechanized high production farming with good rainfall, or for the control of wind erosion where there is large-scale mechanized cereal production. It is less applicable to low input level crop production, or subsistence agriculture.
The principles are equally effective in any conditions - to maximize cover by returning crop residues and not inverting the top soil, and by using a high crop density of vigorous crops. Conservation tillage also has the advantage of reducing the need for terraces or other permanent struc- tures. One of the reasons for low yields in semi-arid areas is the limited amount of moisture available to crop roots.
The available moisture will be increased if the rooting depth is increased and it has been shown that in some cases deep tillage can help, for example on the dense sandy soils luvisols in Botswana Willcocks To browse Academia. Skip to main content. Log In Sign Up. Papers People. El sistema de terrazas fue completamente abandonado y denostado como totalmente inconveniente hasta finales del siglo XX.
Save to Library. Land use planning for water resource conservation in the Krueng Aceh watershed, Indonesia. Flooding in the wet season and drought in the dry season has caused it difficult to fulfill the water needs of the people living in the Krueng Aceh Watershed.
This indicates that land use is not yet in line with the principles of soil and This indicates that land use is not yet in line with the principles of soil and water conservation. The purpose of this study was to create an alternative land use for water resource conservation in the Krueng Aceh Watershed through a hydrological modeling approach by predicting the surface runoff volume and by using the soil conservation service method. The results of the study demonstrated that the use of land for the development of 37, It could also increase the infiltration capacity by Tindakan konservasi harus melihat aspek sosial, ekonomi, dan kondisi riil di Tindakan konservasi harus melihat aspek sosial, ekonomi, dan kondisi riil di lapang sehingga teknik konservasi tanah dan air dapat dilakukan seoptimal mungkin.
It is time we take care of our soil. Integrated agricultural production systems, involving agriculture, livestock, and forest are strategies that improve soil quality. The objective of this work was to evaluate the effect of the integrated crop-livestock-forest system ICLF The soil evaluated was a Eutric Planosol, with a moderate A horizon. The following intercrops treatments were implemented in June I. Brachiaria decumbens. A randomized block experimental design was used, with five treatments.
The analyzed variables were field capacity, permanent wilting point, soil available water, granulometry, degree of flocculation, total porosity, macroporosity, microporosity, saturated hydraulic conductivity, resistance to penetration, and aggregate stability index. After the three-year period, the ICLF promoted no significant physical improvement in the attributes of the evaluated Planosol. Danillo Dutra. A series of greenhouse studies was carried out in order to compare cyanobacterial bio-fertilizer with either organic fertilizers used in the USA composted manure and fish emulsion or fertilizers available in Ethiopia urea and A series of greenhouse studies was carried out in order to compare cyanobacterial bio-fertilizer with either organic fertilizers used in the USA composted manure and fish emulsion or fertilizers available in Ethiopia urea and compost.
Cyanobacterial bio-fertilizer was applied in two forms: solid and liquid. The fertilizers were applied at the same N rate, although the N rate varied by crop kale, maize, chili pepper, lettuce, tomatoa no-fertilizer control was included, and a Randomized Complete Block Design was used with a minimum of three replications.
The solid cyanobacteria treatment yielded the same or higher than the urea treatment, depending on the crop. In addition, cyanobacterial bio-fertilizers reduced soil pH and increased available soil Zn and Fe concentrations. The solid cyanobacteria treatment significantly increased plant Zn and Fe concentrations as compared to both control and urea treatments. A mass balance showed that the Fe applied in the cyanobacteria treatment could explain the increased plant Fe levels; however, this was not true for Zn.
Therefore, the pH reduction caused by the cyanobacterial bio-fertilizer probably contributed to increased plant availability of Zn. Beta-carotene concentrations were significantly increased in lettuce and tomato crops grown with either solid or liquid cyanobacterial bio-fertilizer. We are currently investigating this possibility.
Therefore, development of village-level cyanobacterial production processes is critical to making cyanobacterial bio-fertilizer accessible to smallholder farmers in order to achieve these impacts.
Mekiso Yohannes Sido.The land in any place is used for several purposes such as crop and livestock production, forestry, housing, recreation, residential areas, markets, roads, railways etc. The most desired way of using a particular land is possible when one can understand the type of the soil in the land capability classification which gives complete information regarding various parameters based on which classification is done. Land capability classification is a system of grouping soils primarily on the basis of their capability to produce common cultivated crops and pasture plants without deterioration over a long period of time.
Land capability classification is subdivided into capability class and capability subclass. Important factors on which the classification is based are:. The soils are well managed and cropped under a mechanized system.
Land requiring improvements including clearing that can be possible by the farmer with his own means is classed according to its limitations or likely hazards due to its use after the improvements are made. Land requiring improvements beyond the means of the farmer himself is classed according to its present condition. Other factors like distances to markets, kind of roads, location, size of farms, type of ownership, cultural patterns, skill or resources of individual operators and hazard of crop damage by natural calamities like storms are not considered.
The classification does not include capability of soils for trees, tree fruits, small fruits, ornamental plants, recreation or wildlife. The classes are based on intensity, rather than kind of their limitations for agriculture.
Each class includes many kinds of soil and many of the soils in any class require different management and treatment. In this classification the mineral soils are grouped into seven classes on the basis of soil survey information.
Soils classes as 1, 2, 3 and 4 are considered capable of sustained use for cultivated field crops, those in classes 5 and 6 only for perennial forage crops and those in class 7 for neither. The soils are deep, well to imperfectly drained, hold moisture well, and in the virgin state were well supplied with plant nutrients. They can be managed and cropped without difficulty.
Under good management practices, they are moderately high to high in productivity for a wide range of field crops. The soils are deep and hold moisture well. The limitations being moderate, the soils can be managed and cropped with a little difficulty.
Under good management practices, they are moderately high to high in productivity for a fairly wide range of crops. Land Capability Classes. Source: Dhillon, The limitations are more severe than for class 2 soils.Soil and water conservation engineering. Download PDF. Recommend Documents. Soil erosion and conservation. An analysis of the joint adoption of water conservation and soil conservation in Central Chile. Ecological engineering and nature conservation.
Conservation tillage and biochar improve soil water content and moderate soil temperature in a tropical Acrisol. Conservation laws for a class of soil water equations. Soil conservation and social stability. Schwab, D. Fangmeier, W.
Elliot and R. Frevert, Wiley and Sons, Inc. Looking at an 'old', new book is always a gratifying experience. This one provides the reader with a well-written and thoroughly edited book as well as an updated one. This edition is the fourth of this book.
Soil and Water Conservation Engineering, Seventh Edition
Its content has been thoroughly checked, revised and brought up to date. In the previous editions, engineering approaches to soil and water conservation formed the skeleton and its content. In this edition, the text addresses the interactions and impact which soil and water conservation methods and practices have on soil, water and air quality and on the entire environment.
The major purpose of this book, as was the case with its previous editions, is to provide a basic textbook for agricultural engineers, soil scientists and other professionals interested in soil and water conservation.
The book includes twenty-one chapters, nine appendices and an index, a list of abbreviations, signs, symbols and Imperial to SI units conversion tables. Each chapter is well-illustrated, includes several worked examples and an updated bibliography. The first two chapters cover precipitations and conservation-environment interrelations in general and emphasize their implications on small and large area scales. Problems directly connected with hydrology, namely infiltration, evaporation and transpiration Chapter 3runoff and surface flow Chapter 4 are well-explained in details and illustrations.
In the following chapters the problems of water and wind erosion Chapters 5 and 6 are dealt with and control practices are discussed. Conservation measures, such as tending waterways Chapter 7 and terracing Chapter 8and structures especially constructed for conservation, such as earthworks, dams and flood control, are dealt with Chapters 9 through A Mishra Assistant Professor Dept. View Profile. Site news. Module 1: Introduction and Concept of Soil Erosion. Module 2: Water Erosion and Control.
Module 3: Wind Erosion, Estimation and Control. Module 5: Sedimentation. Module 6: Topographic Survey and Contour Maps. Module 7: Land Use Capability Classification.
Module 8: Grassed Waterways. Module 9: Water Harvesting. Module Water Quality and Pollution. Module Watershed Modeling.
Topic outline. Course Outline File. News forum. Lesson 1 Introduction Page. Lesson 1 Quiz. Lesson 2 Principles of Soil Erosion Page. Lesson 2 Quiz. Lesson 3 Erosion Due to Water Page. Lesson 3 Quiz.
Lesson 4 Quiz. Lesson 4 - Question Bank File. Lesson 5 Quiz. Lesson 5 - Question Bank File. Lesson 6 Quiz. Lesson 7 Gully Erosion Page. Lesson 7 Quiz. Lesson 8 Drop Spillway Page. Lesson 8 Quiz. Lesson 9 Drop Inlet Spillway Page. Lesson 9 Quiz.
Lesson 10 Chute Spillway Page. Lesson 10 Quiz.Excess nutrients in runoff are a major threat to water quality. When it rains, the rain can cause erosion, pick up nutrients and chemicals, and run off into our waterways. On land, these hitchhikers help us grow crops and have nice lawns, but in runoff they sicken streams, rivers, lakes and bays.
Nutrients can lead to harmful algal blooms that kill underwater plants and destroy habitat that aquatic life needs to survive. They can also lead to water with little or no dissolved oxygen, again to the detriment of aquatic life.
Nutrient management and soil and water conservation districts SWCDs play a pivotal role in preventing such runoff. In fact, SWCDs have been in the business of fighting erosion and preventing pollution since the mids. And Virginia's 47 districts still wage the good fight, focusing mainly on on-the-ground work.
DCR works closely with districts and farmers, urban and suburban landowners, and other land managers to cut this harmful runoff, but controlling runoff pollution is everyone's business. Each of us causes runoff pollution; each of us must work to reduce its effects. Visit this page for more information about it. To assist Districts in meeting challenges related to the current public health emergency, in concurrence with the Secretary of Natural Resources, and with the support of the state Soil and Water Conservation Board, the Director of the Department is waiving certain requirements for FY agricultural best management practices BMP cost-share grants.
Click here for additional information. Department of Conservation and Recreation Conserve. Search DCR Site. P-Index Ver. Please send website comments to web dcr.Author by : Glenn O. Sufficient hydrologic information--precipitation, infiltration, evaporation, transpiration and runoff--is given as background for design problems discussed later.
The text makes readers aware that the environment must be considered in the design of soil and water facilities. It also features many example problems, with detailed solutions, to facilitate learning.
Author by : B. Author by : R. It is useful for degree and diploma students of Agricultural Engineering and those working in this field. Author by : Rodney L.
As in previous editions, the purpose of this book is to provide a professional text for undergraduate and graduate agricultural and biological engineering students and for others interested in soil and water conservation in rural and urban areas. Subject matter includes all the engineering phases of soil and water conservation for a one- or two-semester course. Format Available : PDF, ePub, Mobi Total Read : 68 Total Download : File Size : 45,5 Mb Description : Streamlined to facilitate student understanding, this second edition, containing the latest techniques and methodologies and some new problems, continues to provide a comprehensive treatment of hydrology of watersheds, soil erosion problems, design and installation of soil conservation practices and structures, hydrologic and sediment yield models, watershed management and water harvesting.
It also deals with the special requirements of management of agricultural and forested watersheds. This book is designed for undergraduate students of agricultural engineering for courses in hydrology, and soil and water conservation engineering.
It will also be of considerable value to students of agriculture, soil science, forestry, and civil engineering. Author by : Del D. Subject matter includes all the engineering students and for others interested in soil and water conservation in rural and urban areas. Subject matter includes all the engineering phases of soil and urban areas. The authors assume that the student has a basic knowledge of calculus, surveying, mechanics, hydraulics, soils, and computers.
The analytical approach is emphasized and is supplemented by sufficient field data to illustrate practical applications. The text emphasizes engineering principles in the areas of erosion, drainage, irrigation, and water resources.
Tables, charts, and diagrams have been included to provide practicing engineers with readily usable information as well. Many examples and problems are included to emphasize the design principles and to facilitate an understanding of the subject matter.