A proposed pattern of Land Capability Classification system

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1 Eco. Env. & Cons. 15 (2) : 2009; pp. ( ) Copyright@ Enviromedia A proposed pattern of Land Capability Classification system *A.C. Pandey and **N.N. Sirothia College of Agricultural Engineering and Technology, Allahabad Agricultural Institute Deemed University, Allahabad, , U.P. ABSTRACT In this paper a pattern have been proposed for land classification determination as an alternate to the existing Land Use Capability Classification in India. In the proposed methodology, for determination of land class, the procedure have been adopted for award of numerical marks as a weightage to the various soil, land characteristics and to the natural hazards and the sum of this weigtage determines the class obtained by that land and the land is classified accordingly. One basic concept adopted in this classification is that all those lands which are economical to cultivate are suitable for cultivation irrespective of its land slope or other natural hazards. Key words: Land use capability classification system (LCC) INTRODUCTION A Land use capability classification system can be defined as classification of land according to its capability for agricultural production on permanent basis under specified agri-management practices to maintain the soil and land productivity (Hudson, 1971). A LCC helps the farmers, the banks, the government and various agencies and also the public for sale and purchase of land, criteria for giving subsidy and for giving loan on the land; The various land classes directly reflects upon the productivity of land and degree of management practices adopted to maintain its productivity; A class I land is more productive and need least management practices to maintain its productivity and a class IV or V land has low productivity and need higher degree of management practices. Deficiencies in the existing Land Capability Classification system in India In the existing LCC system of India, the land has been classified into eight classes, out of which first four classes are recommended as suitable for cultivation and classes V to VIII are recommended as not suitable for cultivation. The criteria for suitability and non suitability for agriculture are mainly the degree of management practices adopted to maintaining the land productivity and the physical impediments to cultivate the land eg., presence of boulders on the land, steep slope and presence of water on land surface etc. In fact the existing LCC system of India is almost a true copy of LCC system of USA with very few changes eg. land slope. Cultivation is recommended upto 25% slope in India (Soil Survey Manual, 1971) while it is 12% in USA (USDA 1969). In fact in the existing LCC of India, no consideration at all has been made about the agro-economic structure of Indian agriculture or the use of animal power and manual labour for cultivation in India. Demerits in the existing LCC system in India can be detailed as below: a) The lands have been divided into eight classes, first four as suitable for agriculture and last four not suitable for agriculture without giving any consideration to the Indian agricultural condition or agroeconomic structure of India e g. class V land is cat- Corresponding Author : ** Professor Emeritus, CAET, AAIDU, Allahabad, U.P. *Present address : SMS (Agril. Engg) Krishi Vigyan Kendra, East Singhbhum , Jharkhand. acpandey10@hotmail.com

2 354 Eco. Env. & Cons. 15 (2) : 2009 egorized as not suitable for agriculture although it is said that land is moderately fertile but due to presence of boulders or high slope etc. it is difficult to cultivate; This difficulty to cultivate class V land, exist in USA where ploughing and other operations are done with the help of tractors only but in India where bullock cultivation is common it is not at all difficult to cultivate such land. Similarly if water is present on the land surface it may be costlier in USA to drain it out but in India, it is not. b) Cultivation is recommended in India only upto 25% slope although cultivation is quite common even on 100% slope (45 o ) and orchards are found on slopes 150% (56 o ) to 180% (61 o ). Excellent tea gardens exist even on 70% (35 o ) to 80% (38 o ) slopes in Darjeeling and these lands can not be declared as unsuitable for agriculture. c) There are no specific criteria for determination of accurate impact of various soil and land characteristics on different land classes (Dixit and Tandon, 1992; Jaiswal, 1976).; And due to this lacuna there often exist a confusion in case of lands of nearly similar characteristics, as to which class these lands should fall whether in class II or class III or in class III or class IV and so on. d) No consideration has been given to the economics of agriculture in India before suggesting the existing LCC and because of this many lands which are economical to cultivate are classified as not suitable for cultivation. In fact the basic and main criteria for classification of land in India should be economics of cultivation and if land is economical to cultivate, it is suitable for cultivation, irrespective of land slope or other impediments present. In India the wages of farm labourers are very low and unemployment status is also high and under such circumstances the right to cultivate a land can not be denied by saying that land is unsuitable for cultivation especially when land is economical to cultivate. Under condition of unemployment sometimes peoples are compelled to cultivate even uneconomical lands because they have no alternate employment. Basic considerations for an alternate pattern of Land Capability Classification system The demerits in the existing LCC system, discussed above should be removed to the extent possible in order to suggest an alternate pattern of LCC some basic considerations have to be made. The first basic consideration is that all lands are suitable for cultivation if they are economical to cultivate and no land is unsuitable for cultivation only the cost of cultivation varies eg. Mushroom cultivation is done in the building with cemented floors, walls and roofs, similarly in the case of medicinal plant cultivation. With this basic consideration the distinction between a land suitable and not suitable goes away. The lands which are not economical to cultivate may be under cultivation in the state of higher rate of unemployment. With these considerations it is also important that necessary management practices should be adopted permanently, to check the erosion and to maintain and improve the land productivity. These soil, water and land management practices can be divided into five categories like elementary management practices, moderate management practices, intensive management practices, very intensive management practices and exceptional management practices. A list is given below mentioning the type of management practices falling in the categories of elementary, moderate and so on. Elementary management practices (a) Small field bunding (b) Ploughing across the slope or along the contour (c) Cover crop d. Mulching (e) Crop rotation (f) Green manuring as required. Generally two or more of these practices are adopted for class I land Moderate management practices: All the elementary management practices plus (a) Ploughing and sowing across the slope or along the contour. (b) A good crop rotation to check the erosion and to maintain the fertility. (c) Green manuring every alternate years or once in three years. (d) Strong field bunding. (e) Elementary salinity or acidity control pratices. (f) Diversion or marginal bunds to check flooding. (g) Construction of contour bunds for water conservation or graded bunds (terrace) for excess water disposal. (h) Elementary gully control practices. Intensive management practices: Erosion control practices like (a) Land leveling (b) Bench terracing (c) Elementary gully control practices. (d) Water conservation practices e.g. (e) Higher field bunds and cover crops (f) Deep summer ploughing. (g) Excess water disposal provision (h) Green manuring every year or alternate year. (i) If needed instead of three crop in a year two may be adopted. Very Intensive management practices: (a) All possible erosion control practices (b) Contour trenches if needed for pastures. (c) Gully control structures. (d) Diversion bunds and diversion channels. (e) Drainage channels or tile drainage system. (f) Integrated,

3 PANDEY AND SIROTHIA 355 salinity and acidity control practices. (g) Salinity/ acidity resistant crops should be grown. (h) One or two crops to be recommended instead of three and out of two, one crop should be a green manuring crop. Exceptional management practices: (a) Construction of embankment to check river diversion and erosion. (b) Levee or embankment construction for control of flooding. (c) Stream bank erosion control practices. (d) Straightening of water channels and gullies or leveling operation for them. (e) Leveling of elementary or low intensity ravine lands. (f) Control of land slides and surface creep. (g) Ravine control practices. The other consideration should be that system of LCC should be such that no confusion or overlapping should take place while assigning a particular class to a land. To achieve this, a weightage in terms of numerical marks can be awarded to the various soil, land and natural hazards characteristics adversely affecting the land productivity (Srivastava, 1979; Srivastava, 1983; Srivastava and Kazmi 1989). These marks can be awarded on the basis of varying degree of these characteristics of a particular land. The total marks obtained by a particular land will decide its position in Land Classification system (Dhir and Bhola, 1997; Dhir, et. al.1977). Methodology for marks allotments Marks allotment to the various lands is obtained by summing up of the marks received by various characteristics of that land. The various characteristics considered for determination of land class and range of marks allotted to these characteristics is listed below: Each of the characteristics mentioned above have been further divided and awarded marks in order of Table 1. Numerical weightage awarded to various characteristics S. No. Characteristics Range of marks allotted 1 Soil Type 22 to 0 2 Soil fertility status 20 to Soil depth 12 to Organic matter content 4 to -1 5 Rainfall 10 to 4 6 Irrigability 10 to -5 7 Land slope 10 to Soil reaction 2 to Natural hazards 10 to -12 their varying impact on land productivity in following manner. Numerical weightage to soil type Soils have been classified in fourteen categories and marks have been awarded to each category of soil type taking into consideration of their behaviour with respect to: Tillage management, Soil permeability, Available moisture range, Inherent fertility and productivity etc., Soil erodibility, Soil living population (Sirothia, et. al. 1990; USDA, 1957) Tillage management of soil is mainly affected by clay percentage; higher the clay percentage more difficult is its management. Similarly, higher clay percentage reduces the soil permeability but at the same time improves the available moisture range, inherent soil fertility, organic matter content and soil living population & Soil erodibility is low. The affect of silty soil (loam soil) is like a balancing factor between the sand and clay. Loamy soil is considered to be a better soil than sandy soil or clayey soil. But while considering the inherent fertility and productivity, a silty clay loam soil is considered to be better. Marks to various soil type are given below in Table 2. Presence of gravel, rock fragments or minerals will adversely affect the marks allotted to various categories of soil type (Sehgal, 1990). Table 2. Numerical weightage awarded to Soil Type S. No. Soil Type Range of marks Class allotment 22 to 0 1. Silty clay loam Loam Sandy clay laom Silty loam Clay laom Sandy laom Loamy sand Sandy clay Silty clay Clayey sand Sandy soil Clayey soil Gravely clayey soil Marshy land 0 Soil Fertility Status Soil fertility status has been classified into seven classes, in the diminishing order of its impact. Soil

4 356 Eco. Env. & Cons. 15 (2) : 2009 fertility status reflects upon the availability of plant nutrients through the soil. The plant nutrients include major, secondary and micro plant nutrients. A soil, which is capable of effectively meeting the plant nutrient adequately, is termed as highly fertile. The essential soil nutrients include Nitrogen, Phosphorous, Potassium, Sulpher, Calcium, Magnesium, Iron, Chlorine, Manganese, Copper and Zinc etc. These chemicals should be present in the soil at the optimum level to avoid toxicity; or inadequacy. Table 3 shows the marks given to various soil fertility status. Table 3. Numerical weightage awarded to soil fertility status S. No. Soil Fertility Range of marks allotment Status Class 20 to Very high fertility 20 2 High fertile 18 3 Moderately fertile 15 4 Low fertility 10 5 Poorly fertile 4 6 Very poor fertility 0 7 No fertility -10 Soil Depth Soil depth has been divided into seven classes in order of its impact on for crop growth. Soil depth affects the soil capability in reference to availability of plant nutrients, moisture and plant root development. Ground water can rise through capillary action, from a depth of even 3-4 meters; With this capillary rise, plant nutrients and salts also move up. With this consideration greater soil depth is important especially for dry land farming condition and inadequate irrigation. A soil depth of 150 cm is considered to be the minimum for good plant growth. Marks given to various soil depths are shown in Table 4. Table 4. Numerical weightage awarded to Soil depth S. No. Soil depth Soil depth Range of marks Class Cm allotment 12 to Very deep 150 or above 12 2 Deep Moderately Shallow Very shallow Extremely shallow Nil 0-10 Organic matter content Six classes have been proposed on the basis of organic matter content. Organic matter content is calculated in terms of organic carbon or organic matter especially in the A horizon Organic matter content improves the soil structure, soil living population, increases aeration and moisture holding capacity in the soil. Marks given to organic matter content are given in Table 5. Table 5. Numerical weightage awarded to Organic matter content (OM)/Organic carbon S. No. Organic OM Organic Range of matter kg/ha Carbon marks Class % allotment 4 to -1 1 Very high 1.73 & above High Moderate Low Very low Nil Rainfall Rainfall has been divided into six classes on the basis of the degree to which it meets the crop requirement. In most part of India rain water is inadequate and is further adversely affected by skewed time distribution. In this proposed classification system the rainfall factor has been considered in terms of percentage crop water requirement it meets. Numerical weightage allotted, to various degree of rainfall is given below in Table 6 Table 6 Numerical weightage awarded to annual rainfall S.No. Crop production need met by rainfall % Range of marks allotment 10 to % of crop need met by rain % of crop need met by rain % of crop need met by rain % of crop need met by rain % of crop need met by rain 0 6 5% of crop need met by rain -4

5 PANDEY AND SIROTHIA 357 Irrigability The term irrigability has been used here in reference to the availability of water for irrigation of crop to meet the rainfall deficit. Numerical weightage have been awarded to irrigability factor considering the percentage water need,that can be met by irrigation and is given below in Table 7. Table 7. Numerical weightage awarded to Irrigability S.No. Irrigability Range of marks allotment % 10 to Nil -5 Land slope Land slope has been divided into ten classes in order of its varying impact on cultivation, erosion control and management practices to be adopted. Land slope (Bhave, 1970; Dahake, 1971; Dharkar, and Deshkar. 1972) is expressed in percentage or in degree slope. Higher slope means higher erosion, lower infiltration and higher runoff. On slopes higher than 0.5% conservation practices are required and higher the slope, more intensive conservation practices are needed. In India regular cultivation is done on slopes upto 100% and even higher. Very good tea gardens exist on 50 to 80% slopes and orchards even on 150% slope. Numerical weightage awarded to land slope is given in Table 8. Soil reaction Soil reaction has been divided into five classes in order of its negative impact on crop production and management practices adopted to control the same. For a healthy plant growth, a soil should be neutral in reaction. If a soil is acidic or alkaline, the choice of crop and also its production becomes limited. In extreme condition of acidity and alkalinity and salinity, the cultivation becomes difficult. To maintain a favourable soil reaction, moderate to very intensive management practices are required depending upon the soil reaction and the factors responsible for it. Numerical weightages have been awarded to this factor as given in Table 9. Table 8. Numerical weightage awarded to slope percentage S. Slope Slope status Range of marks No. % /degree allotment (10 to -25) 1 0.5% / 0.29 o Nearly level % /0.57 o Very gently sloping 8 3 4% /2.29 o Gently sloping 6 4 8% /4.57 o Moderately sloping % / 8.53 o Strongly sloping % /14 o Moderately steep to steep % / o Steep % /36.87 o Very steep % /45 o Very-very steep % /56 o and above Extremely steep -25 Table 9. Numerical weightage awarded to Soil reaction S.No. Soil class Soil reaction Range of ph marks allotment 2 to Neutral 6.6 to Slightly acidic/ alkaline 6.2/ Medium acidic/ alkaline 5.7/ Strongly acidic/ alkaline 5.2/ Very acidic/ alkaline 4.0/ Natural Hazards Natural hazards can be defined as the factors adversely affecting the plant growth and cultivation and this includes many conditions as listed here. Land: Land slope, adverse land surface like stoniness or presence of cobbles or boulders etc. Soil: Poor or no soil fertility like pure sand or extremely sodic or alkaline or acidic soils, poor to very poor or no soil depth. Climate: Condition like scanty rainfall or very low temperature causing snow cover throughout or the part of the year or very high temperature adversely affecting the plant growth etc. Water table: Water-logging or very low water table

6 358 Eco. Env. & Cons. 15 (2) : 2009 Table 10. Numerical weightage awarded to natural hazard (Intensity of management practices, crop loss due to tempreture or water logging or poor quality irrigation water etc.) S. No. Crop loss and intensity of management Range of marks practices required to control the losses. allotment 10 to Optimum condition no damage and most elementary management practices required % crop loss and elementary to moderate management practices required % crop loss and moderate management practices required % crop loss and moderate to intensive management practices required % crop loss and intensive management practices required % crop loss and even most intensive and exceptional management practices are insufficient -12 adversely affecting the plant growth. Ground water quality:- Highly saline or alkaline ground water hindering the plant growth. Flooding:- Flood water covers due to over flowing rivers, surface runoff etc., adversely affecting the crop growth. The above mentioned factors in natural hazards may adversely affect the crop from moderate to extreme degree and to the extent that no crop is possible. To control the adverse affects, elementary to exceptional degree of management practices are needed. Numerical weightage has been awarded to various stages of natural hazards, causing crop loss or need of management practices, affecting the economics of cultivation. Table 10 indicates the range of marks allotted to above conditions in six classes. Various Land Classes In order to express the land productivity there can be a method of dividing it into various land classes or it can be represented, by award of marks or both the system can be combined in the pattern similar to high school certificates. Award of class and marks allotment according to its productivity helps in precise determination of the productivity within the same class; And in this proposal class system and marks allotment have been combined to facilitate the objectives mentioned above. Here the land has been classified into eight classes, as in the existing LCC, to facilitate the adoption of existing pattern in the proposed one. There still exists scope that these eight classes can be reduced to a more convenient one i.e. it can be reduced to six classes because now the class of suitable for cultivation is no more necessary. For determination of LCC class of a land, the level of various land characteristics of that land are determined and marks are awarded accordingly (Sirothia, et. al. 1990). The marks obtained under various characteristics are summed up and the total marks obtained, determines the class of land. The maximum total marks obtained by a land class can be 100 and the minimum can be even less than zero. In the proposed LCC for India, class I to class VIII lands have been given a numerical weightage ranging in between 100 to 0 marks or less than 0. The class VIII land is expected to be highly uneconomical for cultivation. The numerical weightage allotted to each class of land is in consideration of soil, land and natural hazards land is subjected to. This award of marks may be amended in future after detailed field trails, as per need. The marks awarded to each class is given below in Table 11. Table 11. Allotment of numerical weightage to various land classes S. No. Land Classes Range of marks allotment 1 I 91to100 2 II 73 to 90 3 III 52 to 72 4 IV 38 to 51 5 V 26 to 37 6 VI 15 to 25 7 VII 0 to 12 8 VIII 0< Land Capability Sub-class In the proposed LCC system, the various land use classes are determined according to their production capability and degree of management practices required to maintain this which in turns affects the

7 PANDEY AND SIROTHIA 359 economics of cultivation. In this classification specific causes for adopting the enhanced management practices are mentioned as suffix along with the class of land. And after this the land class is denoted as a sub class of land class. In case a land is in class IV due to erosion than it will be mentioned as IVe and if it has been awarded class IV due to bad climate its sub class will be IVc and if it has come to this class due to the effect of mainly climate and secondary erosion, it will be shown as class IVce and this will be considered as a subclass of class IV land. In this manner land use capability class II, III, to VIII can be further classified into sub classes in the following manner:- IIIe:- Land is subject to erosion, IIIc:- Land is subject to climatic hazards, IIIs:- Land is subject to adverse soil reaction, IIIw:- Land is subject to high water table or water logging and IIId:- Land is subjected to shallow soil depth. These classes may be subjected to more than one hazard and in such a case it will be mentioned as class IIIed or IIIwc and so on. All classes of land from II to VIII have more then one sub-classes. These sub-classes denote the nature of management practices needed to reclaim the land and maintain its productivity. Case Study Efforts were made to compare the proposed pattern of Land Classification with the lands of various land classes of 64 soils mentioned in the book Bench Marks Soils of India (Murthy, et al, 1982). In this effort it was found that some of lands could not be classified because of confusion and some lands were intentionally omitted because of lacuna in the existing system. Few such examples are given below: (i) The Phullen Soil Series located around village Phullen, Mizoram State, 23 o 50 N 93 o 03 E has a dense bamboo forest and this land could not be assigned and class in the existing LCC system. The soil has low fertility, very high organic matter content and excellent rainfall, in the proposed LCC pattern the land has been classified as class IVes. (ii) Jaihing Soil Series around Village Nakari, P.S. North-Lakhimpur, District Lakhimpur, Assam, 27 o 20 N 94 o 03 E has good Tea Plantation. The land has very good soil, moderate fertility excellent soil depth and organic carbon, excellent rainfall and irrigability conditions and is gently sloping but still the land could not be determined in the existing LCC system. In the proposed LCC pattern the land has been classified as IIs. (iii) Thekkadi Soil Series Thekkadi reserve forest, 1.5 km from periyar lake. 09 o 05 N 77 o 14 E, is having a rich and dense forest, soil type is moderate, soil fertility, soil depth, organic matter content and rainfall pattern are all excellent, land is moderately sloppy, such a good land also could not be classified under existing LCC system of India. This land has been classified as IVs under proposed LCC pattern. (iv) Excellent tea gardens in Darjeeling city limits produces high quality tea but in the present system it comes under the category of unsuitable for cultivation because it has slope in the range of 50% ( ) to 80% ( ). (v) At Chaubatia in Ranikhet district very good apple gardens exists on the land slope range of 60% ( ) to 100% (45 0 ). These lands falls under the category of not suitable for cultivation. (vi) In Dehradun district, on Masoorie hills gardens exist on 50% ( ) to 120% (50 0 ) slope and good pastures exist on 80% ( ) slopes; But all these lands fall under the category of unsuitable for cultivation. (vii) In Nepal, on the road, Kathmandu to Pashupatinath temple, 21 km from Kathmandu, a good number of Paddy cultivation bench terrace were observed on 100% (45 o ) slope with excellent paddy crop, all cultivated with manual lobour. Result, Discussion and Conclusion The proposed pattern of Land Classification system, having the combination of weightage in terms of numerical marks and land class have been found to be justified when compared with the land classes awarded to 64 types of lands/soils in the book Bench Marks Soils of India (Murthy, R. S. et al, 1982); where more than 95% results tallies. In the proposed pattern of Land Classification following advantages have been observed : Because of award of numerical marks/ weightage this system offers, determination of land class precisely, accurately and without any ambiguity, and even does not need use of adjectives. This classification system is with consideration of agro-economic structure of India and recommends that all those lands which are economical to cultivate are suitable for cultivation. The lands under cultivation in India, for the past

8 360 Eco. Env. & Cons. 15 (2) : 2009 hundreds of years, specially the tea gardens and orchards are declared as lands unsuitable for cultivation under existing LUCC, hence need change. The poorly fertile lands, under changing pattern of cultivation, now have become economical to cultivate e.g. lands under Amlon cultivation or under flower cultivation and under cultivation of medicinal plants, now can not be declared as unsuitable for cultivation. Under this system of classification it has become convenient to choose the management practices to be adopted and the treatment to be given to the land because of knowledge of precise degree and number of natural hazard, the land is suffering from. With this marks system of classification comparison between the two lands has become more precise meaningful and fact based. With the list of management practices given in this paper, under different category, it has become convenient to choose the recommended ones. In the proposed pattern it has become convenient to field workers for collection, sorting and forwarding the data in a better presentable form, to the scientists. With the knowledge of specific degree of natural hazards without any adjectives, it is very convenient to take decision about the alternate use of land, land subsidy and compensation to be given in case of disasters. The LUC classes obtained have given an excellent co-relation to the existing land class. This proposed LUCC system can be conveniently applied to the Indian sub-continent and also to the other countries because of the consideration of agro-economic structure of India and economics of cultivation. REFERENCES Bhave, N.V. (1970). Project report, unpublished, under guidance of Prof. N.N. Sirothia on Development of Land Use Capability Classification for India. Dahake, P.S. (1971). Project report on An Approach for Land Use Capability Classification for Indian Conditions, unpublished, under guidance of Prof. N.N. Sirothia in the Deptt. of Agril. Engg. A.A.I. Allahabad. Dharkar, D.N. and Deshkar. U.S Project report prepared under guidance of Prof. N.N. Sirothia on Land Use Capability Classification for Indian condition. Dhir, R.P., Bhola S.N and Mann H.S (ed.) Land use capability classification. In Desert Eco-system and its improvement. Central-Arid-Zone-Research-Institute, CAZRI- Monograph. No. 1, pp