5.5 Location as a land quality

Location, in relation to markets and supplies of inputs, is often left out of consideration in land evaluation, or dealt with summarily for lack of data. In the qualitative reconnaissance-scale land classification of Guyana (FAO, 1966), for example, input of fertilizers was considered uneconomic or impracticable beyond a line along the escarpment of the Pakaraima mountains and roughly 200 km from the coast.

Location in relation to markets can be dealt with in more detail in a quantitative land suitability classification, by calculating differences in value of produce and cost of inputs at farm gate as a function of location. A Japanese study, summarized by Fukui (1976), for example, rates this land quality by comparison of bane port cost from land in different locations with the market value of different kinds of produce. The main steps in the study follow.

Transportation cost per tonne-km is determined mainly by the kind of vehicle that can be used, its carrying capacity over the road or terrain and the effective speed. These three are limited by the road width, surface and slope, traffic volume and speed limits, load limit of bridges and other structures, and natural hazards such as heavy snow. Table 11 shows a classification of roads, the most economical kind of vehicle usable on each and the resultant "transport cost index": the relative transport cost, compared with the cost per tonne-km by five-ton truck on a hardsurface good two-lane road. A map is then produced showing "effective distances" from main markets. The effective distance is the sun of distances along roads of different quality each multiplied by their transport cost index.

For each kind of produce considered, the difference between value at farm gate and at market centre or rail head is calculated as a function of effective distance. This difference consists of the transport cost, transport losses (mainly of juicy produce) and market handling fees. Through this difference, the effective distance from markets is then rated in the same way as other land qualities influencing costs or yield levels.

Transport costs of inputs were neglected in the study. These could be taken into account through a correction factor, or calculated separately in eases where they are not small compared with the transport costs of the produce.

There data for a given region are very limited, for example if only the cost per tonne-km over a standard road can be derived from locally available figures, the transport costs from land in different locations can still be estimated by use of the transport cost index (right-hand column in Table 11) for different kinds of roads.

Table 11 ROAD CLASSIFICATION AND TRANSPORT COST INDEX IN JAPAN (adapted from Fukui, 1976)

Road		Vehicle								transport cost index
kind and surface width		type and cost, yen/day	load, tonne		standard speed km/h		transport capacity tonne-km/hour
level, hilly or urban 1/				l	h	u 1/	l	h	u	l	h	u
double lane over 5.5 m	hard	5-ton truck 6045	5	50	30	25	250	150	125	1.0	1.7	2.0
	gravel		5	36	21	18	180	105	90	1.4	2.4	2.8
	earth		4	28	17	14	112	68	56	2.2	3.7	4.5
single lane 3.5-5.5 m	hard	5-ton truck 6045	5	42	25	21	210	125	105	1.2	2.0	2.4
	gravel 2/		5	30	18	15	150	90	75	1.7	2.9	2.3
	gravel 3/		5	29	17	14	145	85	70	1.7	3.1	3.6
	earth		4	23	14	12	92	56	48	2.7	4.5	5.2
single lane steep or with sharp curves 4/ 3.5 m	hard	2-ton truck 3995	2	42	20	15	84	40	30	2.0	4.2	5.5
	gravel		2	32	14	11	64	28	22	2.6	6.0	7.5
	earth		2	25	11	8	50	22	16	3.3	7.5	10
cart track in poor condition earth 1.5-3.5	gravel	animal cart 1500	1.5 (1.2 hilly)	5	4		7.5	4.8		8.4	13
	earth		1.2 (1.0 hilly)	4.5	4		5.4	4.0		11	15
narrow track 1.5-2.5 m		small tractor 1000	0.3	8	8		2.4	2.4		14	14
forest cableway		cableway 5640	0.6		16			9.6			24
less than 1.5 m or no road		horse 1200	0.1	5	5		0.5	0.5		100	100

1/ 1 - level; h - hilly: roads with more than 80 m of ascent + descent per km (mean slopes more than 8 percent); u - urban: roads with a low speed limit.
2/ Roads with a regular bus service.
3/ Roads without a regular bus service, generally less well maintained than 2/.
4/ Roads with slopes over 15 percent or with curves of less than 10 m radius are assumed to be unusable for 5-ton trucks.

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