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Module 1: Revision in Forest Management

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    Forests and Their Management Dr. Ankur Awadhiya Department of Biotechnology Indian Institute of Technology, Kanpur Module - 12 Revision Lecture - 34 Revision (Part 1) (Refer Slide Time: 00:24) (Refer Slide Time: 00:26)[FL]. So, now, we have reached to the end of this course, and in this lecture, we will start doing the Revisions. So, we started this course by looking at what a forest is. (Refer Slide Time: 00:28) (Refer Slide Time: 00:29)(Refer Slide Time: 00:30) (Refer Slide Time: 00:31)(Refer Slide Time: 00:31) (Refer Slide Time: 00:33)(Refer Slide Time: 00:34) (Refer Slide Time: 00:35)(Refer Slide Time: 00:36) So, this is a typical forest; you find different animals in the forest; animals, birds, signs some larger animals, some fungi and then, we looked at different definitions of the forest. (Refer Slide Time: 00:38) So, we looked at the dictionary definition; “a large area covered chiefly with trees and undergrowth” from coming from the Latin word, “forest” which means “outside.”(Refer Slide Time: 00:49) Then, we looked at the technical definition; “an area that is set aside for the production of timber or other forest produce or maintained under woody vegetation for certain indirect benefits such as climate or protective.” (Refer Slide Time: 01:13) Then, we looked at ecological definition; “plant community, predominantly comprised of trees and other woody vegetation usually with a closed canopy.” Followed by a legal definition, “an area of land proclaimed to be a forest under the forest law.” The FAO definition of, the food in agriculture of organization; “all lands bearing vegetative associations dominated by trees of any size, exploited or not, capable of producing wood or of exerting an influence on the climate or on the water regime, or providing shelter for livestock and wildlife.” (Refer Slide Time: 01:39) Next, we looked at the supreme court’s decision in the Godavarman case, in which case the supreme court has said that, “the word forest must be understood according to its dictionary meaning. And, this description covers all statutorily recognized forest, whether they are designated as reserved forest, protected forests or otherwise for the purpose of Section 2(1) of the Forest Conservation Act.” Then, we looked at forest land, and we said that the term forest land not only includes forests as understood in the dictionary sense, but also any area that is recorded as forest in the government record; irrespective of its ownership. So, no matter who owns the land, it is a forest land.(Refer Slide Time: 02:21) When we looked at forest management which is an integration of the silvicultural practices and business concepts in such a way, as to best achieve a landowner’s objectives, and then you have different kinds of objectives that are being met using forest management. (Refer Slide Time: 02:40) In the second lecture, we looked at classification of forest. So, there are different kinds of forest, and it is determined by the amount of rainfall, the temperature, soil fertility, soil type, colonization by species, and dynamics between different species. So, these are all different factors; they can be abiotic factors or biotic factors that determine what grows at any place and climate, is the most important one. (Refer Slide Time: 03:04) And so, if you look at this curve, you have angle precipitation on the y-axis and average annual temperature on the x-axis. And, we say see that depending on the temperature and the rainfall of different areas, we have different kinds of forests. (Refer Slide Time: 03:22) In India, we said that we have 6 major types of forests; tropical moist, tropical dry, montane subtropical, montane temperate, subalpine and alpine. (Refer Slide Time: 03:33) Then, we looked at all of these in more detail. So, tropical moist forest; so, you have tropical; it is warm moist, it is wet. So, you have wet evergreen, semi-evergreen, moist deciduous, littoral and swamp vegetation. (Refer Slide Time: 03:48) So, then, we looked at all of these in more detail. So, wet evergreen; dense and tall trees entirely evergreen or nearly. So, found in Western Ghats, Andamans and Nicobar’s, North East India common species are Jamun, Mango and Jackfruit semi evergreen.(Refer Slide Time: 04:02) So, you have dominants which include deciduous species, but evergreens are also predominant. It is found in Western Ghats, Andaman and Nicobar Islands, Eastern Himalayas and we have a mix of wet evergreen trees and moist deciduous trees. (Refer Slide Time: 04:21) Now, moist deciduous forests; you know, you have dominants are mainly deciduous, but sub dominant and lower story is largely evergreen. Top canopy is even and dense, and 25 meters of height in general. It is found in most of India except in Western and North Western regions, and the common species are teak, Sal, mango, bamboo and rosewood. (Refer Slide Time: 04:45) Next, we have littoral and swamp forest; the general composition is mainly evergreens of varying density and height, but always associated predominantly with wetness. And, these are found in Andaman and Nicobar islands, delta regions. And, a common species is mangrove which we saw, in the lecture, that it has a number of adaptations that make it suitable for a life in such areas. So, the littoral and swamp forests are found in wet areas. (Refer Slide Time: 05:15)Next, we have tropical dry forests. Now, these are tropical. So, high temperature and these are dry, because you have less amount of rainfall. And, there are 3 different types you have dry evergreen; you have dry deciduous, and you have the thorn forest. (Refer Slide Time: 05:29) Now, dry evergreen; the composition is hard leaf evergreen trees which predominate with some deciduous emergent; often dense, but usually under 20 meters of height. Found in Andhra Pradesh, Karnataka coast; common species are iron wood black pump plum and Ceylon ebony. (Refer Slide Time: 05:47)Dry deciduous trees; no, remember that deciduous trees are those trees that shed their leaves in certain season of the year or certain part of the year, typically, to conserve moisture. Now, in the case of dry deciduous forests, the general composition is entirely deciduous or nearly. So, top canopy is uneven rarely over 25 meters in height, found in Madya Pradesh, Gujarat, Andhra Pradesh, Karnataka, Tamil Nadu; and, the common species are sal, acacia and bamboo. (Refer Slide Time: 06:17) Then, we looked at thorn forest. So, thorn forest at xerophytic vegetation, very less amount of water is there. So, the general composition is deciduous with low thorny trees; and xerophytes pre predominates low canopy; top canopy is more or less broken and these are less than 10 meters in height. Found in North, West, Central and South India. Common species include things like spurge and cactus. (Refer Slide Time: 06:44) Next, we looked at montane sub-tropical forest. So, these are in mountainous areas and these are subtropical. So, it is not that much warm now. So, you have broad leave vegetation, pine vegetation and dry evergreen forests. (Refer Slide Time: 07:01) Now, broadleaved forest as the name suggests this these have brought sized leaves. So, these are broadleaved forests, largely evergreen high forest found in Eastern Himalayas and Western Ghats and common species include oak, alder, chestnut, birch, cherry and bamboo.(Refer Slide Time: 07:18) Next, we have pine forests. So, the general composition is pine and associates that predominate. Now, pine is coniferous vegetation in which you have needle-like leaves. Now, in these forests; these are found in Shivalik hills, Western and Central Himalayas, Khasi, Naga and Manipur hills. The common species are pine, chir, oak, rhododendron, sal and amla. (Refer Slide Time: 07:43) Next, we have dry evergreen forests; the general composition is low xerophytic forests and scrub. So, xerophytic is dry vegetation that is growing in drier areas. These are found in Shivalik hills and the foothills of Himalaya’s; common species include things like pomegranate and olives. (Refer Slide Time: 08:03) Next, we have montane temperate forests which are of 3 categories; wet, moist and dry depending on the amount of rainfall that you have in these areas. (Refer Slide Time: 08:12) Montane wet forests. The general composition is evergreen, but without coniferous species. So, you find these in Eastern Himalayas and in the Nilgiris; the common species are rhododendron and oak. (Refer Slide Time: 08:27) Next, we have montane moist forests. So, you here you have evergreen forest mainly scleriphyllous, oak, and coniferous species; found in Western Himalayas and Eastern Himalayas, and the common species include oak, walnut, rhododendron, bamboo and fern. (Refer Slide Time: 08:45) Next, you have montane dry forest. So, here the general composition is coniferous forest with sparse xerophytic undergrowth; found in places like Lahul, Kinnaur, Sikkim. So, these areas are very cold areas and very dry areas. The common species include oak, maple, ash, fir, juniper, deodar, chilgoza. (Refer Slide Time: 09:09) Next, you have sub-alpine forests. So, the general composition is stunted deciduous or evergreen forest. Usually close formation with or without the confers. Found in Himalayas of Kashmir to Arunachal Pradesh; common species include red fir, birch, large and rhododendron. (Refer Slide Time: 09:28)And then, we have the alpine forests. Now, alpine forests are typically on the tops of mountains; very cold areas, and you have two different categories: moist alpine and dry alpine. (Refer Slide Time: 09:38) . Now, alpine moist forests have low, but often dense scrub of evergreen species; found in parts of Himalayas and in the Myanmar border. Common species include things like rhododendron, birch, moss and fern. (Refer Slide Time: 09:54)The alpine dry forests. The general composition is xerophytic scrub in open formation, mostly of deciduous nature. These are found in Himalayas from 3000 to 4900 meters, and the common species are black juniper, honeysuckle and willow. So, basically, what this lecture was telling us was that, in different areas, you have different kinds of vegetation which is adapted to different kinds of conditions in those areas; and, these conditions include both the biotic factors as well as the abiotic factors. (Refer Slide Time: 10:27) Then, we looked at major Indian habitats and their residents. (Refer Slide Time: 10:30)So, we looked at alpine meadows. So, you have huge lush grassland. (Refer Slide Time: 10:33) (Refer Slide Time: 10:35) In Jammu and Kashmir and Uttarakhand, you have alpine forests.(Refer Slide Time: 10:39) (Refer Slide Time: 10:41) Moist deciduous forest, dry deciduous forest. Now, as you can see in the case of the moist deciduous forest, the forest floor is looking very green in colour. Whereas, in the dry deciduous forest, you have of forest floor that has and that is full of dry leaves. (Refer Slide Time: 10:55)Next, you have the scrub forest in Rajasthan. So, it like this is in Ranthambhore national park. (Refer Slide Time: 11:01) You have sand dunes in Jodhpur. So, here again, you have less amount of water that is available; the trees are short in height. You have ample amount of breaks in the canopy and you also have thorny vegetation.(Refer Slide Time: 11:17) But then, even these are very important for certain species such as this spiny tailed, lizard. (Refer Slide Time: 11:20) Then, we looked at the Runn of Kutch. Here also, it is a very open sort of vegetation, and if you have areas where you have water, then you will find different species. (Refer Slide Time: 11:26) (Refer Slide Time: 11:31) When you have Brahmaputra floodplains; on the back, you can see that you have a very dense vegetation. In these areas which where you have the floodplains. Because of the yearly floods; so, the plants are unable to grow in these areas, I the large trees are unable to growing these areas and so, you get very good grasses that support number of species such as the rhinoceros.(Refer Slide Time: 11:56) (Refer Slide Time: 11:58) Then, we looked at Shola forests as are found Coorg.(Refer Slide Time: 12:02) We looked at equatorial forests. Now, in the case of equatorial forests, you have ample amount of rainfall; ample amount of sunshine. So, it is a very dense vegetation; it is very difficult to go through this forest, and the your trees are very large in size. So, for instance, you can see this piece of log that is being dragged using an elephant and you can see how large it is. (Refer Slide Time: 12:23) Then, we looked at the mangrove forest, which in which case the plants are very well adapted to a life with lots of water. (Refer Slide Time: 12:34) (Refer Slide Time: 12:35) Next, we looked at the value of forest. And, we began with this chart which said that the total economic value depends on use value and the non-use value. Now, use value is something in which case you are using the resource. Non use value is where you are getting a value even though the resources not being used. Now, in this case, the use value is comprised of to the direct value, indirect value, and option value. And, the non use value is comprised of existence value, altruistic value and bequest value. (Refer Slide Time: 13:06) (Refer Slide Time: 13:10) Now, use value is value arising of a use of resource. Non use value is value arising even though the resource is not being used. (Refer Slide Time: 13:15) Now, the use value comprises of direct value. So, direct value is something that we are using directly, such as consumptive values and the non-consumptive values. Now, consumptive values are those in which, if one person is using those resources, the they are not available in that much amount for use by another person. So, a good example is timber. So, there is a tree, and if I extract the timber out of that tree, you will not be able to extract timber from the same tree, because the timber is now gone. It can either be used by you or it can be used by me. So, we have the consumptive and productive values, such as timber, firewood, medicines grazing, non-timber forest produce and water. And then, we have non consumptive values, such as recreation or ecotourism, education, and research, human and wildlife habitat etcetera. So, a good example of a non consumptive value is a tiger. So, if I see a tiger and I derive a value of say 1000 rupees by seeing this tiger. So, if you see this tiger, the value has not gone down because I have seen this tiger. So, essentially, whenever any person is using a non-consumptive; whenever any person is doing a non-consumptive utilization of a resource, then the resource says amount and the quality remains the same for use by another person as well. So, the direct value is consumptive and non-consumptive values.(Refer Slide Time: 14:52) Then, the indirect values include watershed benefits such as agricultural productivity, soil conservation, groundwater recharge, regulation of stream flows; ecosystem services such as nitrogen fixation, waste assimilation, carbon sequestration and storage microclimatic functions; and evolutionary processes such as global life support and biodiversity. Now, the point in the case of direct of indirect value is that, we are using these values they are important for us, but we are not using them directly. So, for instance, if there is nitrogen fixation that is happening somewhere; so, this nitrogen fixation that is being done biologically. We are not using it directly; it is there to support a different number of different life form and so, it is in indirect value(Refer Slide Time: 15:40) Next, we looked at option value. It is an option for the future; direct and indirect use of biodiversity of the forest. So, in this case what we are saying is that we are not using it, but we want to retain an option that this resource should be available for a future use. If we wanted you to use it in future; so, just because you want to use it in future, you are maintaining it today. So, that is an option value. We do not know when we are going to use it; we do not know if we are going to use it, but we still want to maintain this resource to have this option of using it in, at a later stage, if it is required. (Refer Slide Time: 16:19)Next, we looked at existence value; in the value deriving from knowledge that the resource continues to exist such as the polar bear. So, even though you are not using a polar bear in any way, but still if the polar bear exists; in this species has not gone extinct. So, we are feeling happy about it. So, this is the existence value. (Refer Slide Time: 16:40) Then, you have altruistic value; value derived from the knowledge of use of resources by others in the current generation. A good example would be the tigers of Sunderbans. So, if I am living in Madhya Pradesh and I am not using those tigers, but I know that my fellow citizens, my fellow compatriots of the same planet are using that resource it is providing them livelihood and so, I am happy, because they are able to use this resource. So, this is altruistic value; it is different from a selfish value.(Refer Slide Time: 17:12) . And then, third is the bequest value. The value of living use and non-use resources; use and non-use values for off springs or future generations. So, in this case, we are giving this these resources as a bequest to the future generations. So, we are just managing them; we are conserving them, so that our children or our grandchildren or the future generations will be able to use these values. So, we are giving them as a bequest; as a gift. Now, with all of these different values, we also have several methods of valuation. (Refer Slide Time: 17:48)So, there are 3 accepted approaches for valuation. The first one is the market prices method or the revealed willingness to pay. So, in this case, you are looking at what is the price that any commodity or any resource is demanding in the market. So, the first one is market price method. So, in the case of your forests, they are providing you n number of resources. So, for instance, if you are extracting timber out of the forest, and you we are extracting say 100 tons of timber from the forest; what is the price of 1 ton of timber? Multiply that with 100, and you get the market value of timber that you are getting every year. Now, suppose you are also using this forest for, say, a non-timber forest produce such as fruits and you are extracting say 50 tons of fruit. So, you find out the market price of 1 ton of fruit; multiply that with 50 and you get the total amount of market value that you are deriving out of the 50 tons of fruits. And so, you make a list of different resources that you are extracting from the forest. And, for each of them, you figure out how much is the amount that; or how much is the quantity that you are extracting for from the forest. And, you also figure out what is the market price of each of these commodities that you are extracting. So, you multiply the market price with the amount or the quantity to get the economic value of each and every commodity that you are extracting from the forest; add them up and you get a market price of the forest. Next, you have the hedonic pricing method. So, hedonism is a in the sense of feeling happiness. So, if you have a forest; so, the lands that are near to that forest will be having less amount of pollution or probably people will be able to see the wild animals. So, in that case, there is a possibility that certain prices of goods will go up. So, a good example was that you have two buildings; one is near to a road, which is having a large amount of noise; a large amount of smoke and dust. On the other hand, you have another building of a very similar size; at a very similar location or distance from the industrial centers. And, the good thing about the second building is that it is right next to a forest and so, the amount of dust and smoke and noise is less So, typically, people will be willing to pay a premium or more amount of money for the second building. So, the difference between the rates, multiplied by the total number of flats that you have in that in the second building, will give you an idea of the price that people are willing to pay to get the happiness of living in the second building. So, this is the hedonic pricing method. Now, the third one is the travel cost method. So, in this case, people travelled to see a forest from different locations. And, whenever spending money on transportation; they are spending money on eating outside; they are spending money for lodging and boarding; they are spending money to get into the forest; paying the paying the gipsy fees; paying the guide and so; if you add up the different amounts that people are willing or that people are actually paying to come and see your forest. So, in that case, you can get a value of the forest. The second method is a circumstantial evidence or the imputed willingness to pay, such as a replacement or substitute cost. So, in this case, we were saying that you have a forest that is right next to the oceans and this forest is protecting the lands from tsunamis. Now, if you let go of these forests. If you cut these forests, but still you want to have protection from the tsunamis.  So, you have the false form quotient, which is d at 0.5height divided by the dbh.(Refer Slide Time: 56:56) You also have the rue form quotient which is the diameter at 0.5 height divided by zero point divided by diameter at 0.1height. (Refer Slide Time: 57:05)(Refer Slide Time: 57:09) (Refer Slide Time: 57:11)(Refer Slide Time: 57:12) (Refer Slide Time: 57:13) Then, we looked at a problem looked at how to compute true and false form quotients and the form factors.(Refer Slide Time: 57:17) (Refer Slide Time: 57:18) Next, we looked at measurement of tree attributes in terms of the diameter.(Refer Slide Time: 57:20) So, diameter is measured at the breast height. Breast height is different in different countries, and the diameter can be measured as diameter over bark or diameter under bark. (Refer Slide Time: 57:29) Now, we looked at different formal rules; whether if the tree is standing vertical on a flat ground or on a sloppy ground, if it has some irregularities, and so on so.(Refer Slide Time: 57:36) (Refer Slide Time: 57:37)(Refer Slide Time: 57:40) (Refer Slide Time: 57:41)(Refer Slide Time: 57:42) (Refer Slide Time: 57:43) If you have a tree that has a forking, that is below the breast level; in that case, you considered it to be two trees; such as and if it is occurring above the breast height, then you consider it to be one tree.(Refer Slide Time: 57:50) So, this is one tree, and this is two trees. Now, we saw that diameter can be measured using calipers. (Refer Slide Time: 58:00) (Refer Slide Time: 58:02)We looked at how a caliper is used, and we looked at the pros and cons of the caliper and tapes. (Refer Slide Time: 58:04) (Refer Slide Time: 58:05). (Refer Slide Time: 58:05)(Refer Slide Time: 58:06) (Refer Slide Time: 58:12) Now, a tape always overestimates the cross-sectional area.(Refer Slide Time: 58:16) (Refer Slide Time: 58:19) Now, we also looked at measurement of the tree height. So, in the case of tree height, we said that total height is equal to bole height plus the ground length. You can have a direct measurement in which you are measuring the height directly by using instruments or by climbing on the tree, or you can make use of indirect measurements, such as the method of similar triangle and the method of trigonometry.(Refer Slide Time: 58:24) (Refer Slide Time: 58:32) (Refer Slide Time: 58:39)(Refer Slide Time: 58:40) In the case of similar triangle, we looked at the shadow and stick method, and also the Christen’s hypsometer. (Refer Slide Time: 58:42) (Refer Slide Time: 58:44)(Refer Slide Time: 58:46) (Refer Slide Time: 58:47)(Refer Slide Time: 58:48) And, in the case of trigonometry, we make use of these relations; we make use of these values of sin, cos, and tan theta for different angles. And, we can make use of this instrument called Blume Leiss to directly get an idea of the height of the tree. (Refer Slide Time: 58:55)(Refer Slide Time: 58:58) (Refer Slide Time: 58:59)(Refer Slide Time: 58:59) (Refer Slide Time: 59:00)(Refer Slide Time: 59:02) Then, we defined the basal area of the tree as the area occupied by the cross section of the tree trunk, typically at the breast height. (Refer Slide Time: 59:12) So, area is pi by 4 d square, and in the case of a stand basal area, you sum up the basal areas of all the trees in the stand, and it is typically expressed in terms of per unit area of land.(Refer Slide Time: 59:20) (Refer Slide Time: 59:24)(Refer Slide Time: 59:26) (Refer Slide Time: 59:27) Now, stand basal area is a good indicator of crowding and we saw how to compute it; by direct computation and also by the spacing factor method. Now, spacing factor is defined as the average distance between the trees divided by the average stem diameter, and if we plot the basal area versus the spacing factor, we get this curve. (Refer Slide Time: 59:34) And so, if you know this spacing factor, you can very easily figure out the basal area of this stand. So, that is all for today. Thank you for your attention [FL].