2. Watershed management

Transcript

Hi friends, in the previous lectures we studied about the soil and moisture conservation measures that are being adopted in drylands both under arable and non-arable land management. In this lecture we will study about the concepts of Watershed Management. As you all know soil, water and vegetation are the basic natural resources. Because of the inappropriate management techniques these resources have been depleted, and they have been over-exploited and leading to problems like soil erosion, nutrient loss and so many other factors. So soil, water and vegetation are being depleted due to our own inappropriate technological measures. So what happens, because of these soil erosion problems, there will be decline in the crop yield and food security problems.

The ultimate effect will be on the decline of the crop production and subsequent food security problems. So the watershed management is one of the key factors, which aims at reducing the soil erosion and increasing the soil production and ensure food security. So watershed management, it is being adopted for optimum development of land, water and plant resources. So watershed management is mainly meant for the optimum management of these resources. Let us see what is the concept of watershed management. The watershed is defined as any surface area, from which rainfall is collected and drained through a common point. In a simple way it is defined as any surface area from which rainfall is collected and drained to a common point. So it is also, the term is also synonymous with the catchment area or the drainage point. So in this way watershed can be defined. It is a common point where the rainfall is collected and drained to a common area.

So watershed size. What is the size of the watersheds? The watershed size varies from a few hectares to a thousands of hectares. There are three types of watersheds.

• Micro watersheds
• Mini watersheds, and
• Macro watersheds

So these micro watersheds. Number of micro watersheds will become mini watersheds. And these mini watersheds will be part of the macro watershed. In this way the watersheds have been sized, differently according to size; different groups of watersheds are there. What happens in case of watershed management? In case of watershed management, there is integration of technologies within the natural boundaries for optimum development of land, water and plant resources to meet the basic needs of people and animals in a sustainable manner.

We have understood the land, water and plant are the basic needs; natural resources. But in case of watersheds, these three resources have been integrated, and here the resources are being managed in an integration of technologies. So in a watershed area, there is the integration of technologies concerned to these resources. Coming to a picture, how a watershed looks like. See the picture. This is an area of the watershed from which this is the area where the water is collected and it is formed to a common ledge; and it will be led into the common drainage point. Here also in the second picture we can see that this is the whole figure of the watershed, from which from the top the water is collected through a different aspects, and it is letting into a common point.This is how a typical watershed looks like. And this is a one more figure, wherein the whole macro watershed looks like. So it will be in a rugged area, so several integration of technologies will be there. And here the water is collected from the common point and it is led into a common point or an inlet point.

So what are the objectives on which the watershed management is based on. There are some five objectives.

• Number one objective is. Effectively conserve rainwater, soil and vegetation. So it is to conserve the three basic resources. Soil, plant and vegetation resources. Whatever the surplus water is available, so it makes the surplus water to store in a common point and then it can be used up.
• The second is, promote sustainable farming and stabilize the crop yields by adopting suitable cropping and crop management systems. It is also having an objective of adopting cropping and cropping system practices, crop related aspects. For what; to promote sustainable farming and to have a better yield aspects.
• Then the third one is, cover the non-arable area effectively through afforestation, horticulture and pasture development based on the land capability. So watershed not only covers arable area. So watershed it has an objective of covering the non-arable area where horticulture, pasture components are being integrated, so as to based on the land capability classifications.
• Then the fourth objective is enhance the income of the individuals by adapting alternative enterprises. Here it also watershed management. It also an objective of looking into the individual farmer’s preferences, wherein alternative farming enterprises can also be adopted. For example livestock, poultry, dairy. Like these enterprises can also be adopted. It is also one of the objectives of the watershed management.
• Then fifth objective is restore the ecological balance. By adopting all these practices, the foremost objective of the watershed management is to restore the ecological balance.

This watershed management is mainly concentrated under land capability classes. So here is the chart, where as you move from the class 1 to class 8 the increasing limitations and hazards with respect to land increases. Up to land 1st land to 4th group, which is fit for cultivation. And from 5th to 8th the land is not suitable for cultivation. But the watershed management, it operates in all the classes of the land capability. What are the components? Then what are the components. It has objectives. What are the components of the watershed management?

• The treatment of arable and non-arable land for effective in-situ and ex-situ moisture conservation. It takes into account the arable and non-arable management, and also in-situ and ex-situ moisture conservation. In-situ moisture conservation means; the way the rainfall falls, at that area only the moisture is conserved. This is called in-situ conservation. Ex-situ soil moisture conservation. Ex-situ means, outside the rainfall area the moisture is also conserved. In this also it is also having arable components.
• Next implementation of the programs like afforestation, horticulture, agro-forestry, pasture production in stored water/moisture. By effectively implementing the soil and water conservation measures the watershed as a component, wherein it is going to implement the afforestation programs, the horticulture programs, agro-forestry programs, then pasture related programs in a stored soil moisture.
• Then the third component is identification of a sound crop production system and its implementation through the involvement of developmental and input agencies. After having afforestation it also has the component of identification of sound crop production practices with the help of local developmental departments. And developing suitable infrastructural facilities and people’s organization to maintain the developed services. After developing the services it has a component, wherein the infrastructural facilities are being created effectively and the people’s participation will be ensured. And this is having, and like this it is having major five components of watershed management.

Coming to the what are the principles. On what principles this watershed management has been laid.

• One is utilizing the land according to its capability. I have already dealt with you the land capability classes. So it has a principle of utilizing the land according to its capability.
• Then second one is conserving as much rainwater as possible at the place where it falls. This is nothing but in-situ soil and moisture conservation. Where the rainfall falls, at that area only, at that point only, it has a principle of storing the moisture; conserving the moisture.
• Then draining out excess water with a safe velocity and diverting it to storage points for future use. Wherever the excess moisture is available. So it has the principle of, the storing this at a safe velocity and diverting it to the storage structures, where the water is stored in a safer way, which can be used for supplemental irrigation to the crops at their critical stages.
• Then coming to avoiding gully formation and checking at suitable intervals to control soil erosion. It also has the principle of carrying out the practices in non-arable lands, wherein in non-arable lands also it has a principle of soil and moisture conservation by adopting gully formation, check basins and other practices.
• And increasing cropping intensity and land equivalent ratio, through inter-cropping and sequence cropping. So it is having a crop management aspects also. The principles of crop management here, mainly concentrate towards the cropping systems, wherein different types of cropping systems are adopted, so that the cropping intensity will be doubled.
• Then safe utilization of marginal lands, through alternative land use systems. We have already studied, what are the land use systems, alternate land use systems. So utilization of the marginal lands, through alternative land use systems. It’s also a principle of watershed management.
• Then coming to the ensuring the sustainability of the ecosystem benefiting the man-animal-plantland-water complex.
• Then maximizing the combined income form the interrelated and dynamic crop-livestock components. In a watershed management it has a principle, wherein the farmer will be having the crop component as well as the livestock component. Watershed principle, it also helps in enhancing the income of the farmers, through both this crop component as well as the livestock component.
• Stabilizing total income and cutting down risk during aberrant weather situations.
• Improving infrastructural facilities with regard to storage, transportation and marketing. After the successful crop growth, it has also principle of creating infrastructural facilities which is related to marketing, storage aspects.

In this way it has many principles. So you can see the figure. Here are the four stages. This is the first stage, this is the second stage and this is the third stage, this is the fourth stage. During the 1992 the whole area has been degraded. And suitable management practices have been adopted. And in the year 1998 it has become now. In 2003 more vegetation has come up. And in the 2013, the land is able to cultivate. So it is possible through the watershed management, that degraded land can be brought back to the cultivation aspects.

Then how to planning for watersheds.

• First is the characterization of the natural resources. Characterize the natural resources. Water, vegetation and soil through the imaginary maps or resource maps. Estimate the area covered by major crops can be obtained.
• Then location of structures like check dams, farm ponds. In a watershed area, where should the check dams come, where should the farm ponds; water harvesting structures should come, we have to decide.
• Then comprehensive planning of various activities is then carried out.
• Then after that mechanical, agronomical, agro-ecological and forestry measures of soil and water conservation are then planned and implemented. In this way water shed is being planned stepwise.

Then coming to the concluding remarks. The integrated watershed management is the key to efficient use of natural resources. There is no doubt in that plant, water and soil resources can be efficiently managed by the watershed management, particularly in rainfed areas where water is the limiting factor. In the particularly the area where water is a limiting factor. Integrated watershed management practices can be designed, and they can be adapted to derive fruitful results.

With this I am concluding this lecture.

Thank You.