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Topography :
To providing this layer at first by using DEM layer , slope map was obtained and then this map was multiplied by 0.33 , and at last the topographic factor map was obtained .The average of this factor in the study area is 7.36 .

Ground Cover :
To providing this factor, at first we digitized plant cover map and then in this map based on the bare grounds percent, a new data field was created . The average of this factor in the studied basin is equal 9.88 .

Land use :
With due attention to the crop canopy percent in each cover type , plant cover map based on X₇ value was encoded and same as previous layers, in this map a new data field was created .The average of this factor in the whole basin is equal 14.04.

Erosion condition :
This factor was obtained based on the BLM method .In this method is used from 7 factor : surface erosion, land cover, rill erosion, surface litter, demolition traces on the ground surface, surface flows traces and gully erosion . By field surveying , the score of these factors in each geomorphologic facies was determined and then with digitizing geomorphology map , this map was encoded based on X8 factor value and a new data field (based on X₈ factor) was created in this map . The average of this factor in Kashmar basin is equal 3.84 .

Channel erosion and sediment transport :
To determining of this factor, we applied the gully erosion score (or SSFg in the BLM method ) . Based on this factor, geomorphology map was encoded and a new data field in this map was created .

The average of this factor in the urban watershed of Kashmar was obtained 0.21

Providing of sediment yield score map , sediment yield map and erosion map :
To providing sediment yield score map , at first X₁ , X₂ , X₃, X₆ , X₇ , X₈ , and X₉ factor maps were intersected two by two and at last in the new map, these existing data fields ( 7 fields ) were summed together and a new field was created . Then this map was rasterized based on this new field and was summed with X4 and X5 factor maps (provided in the previous steps ) and at last sediment yield score map was provided .With applying the equation 1 on the sediment yield score map , the amount of sediment yield in each pixel was obtained . To providing erosion map, at first based on the following equations, the amount of SDR in each subbasin was obtained .

{4} SDR= 43.4(A) ^–0.1753       if basin area (A) is less than 10 square mile .
{5} SDR = 46.7 (A)^–0.2071       if basin area (A) is between 10 to 100 square mile .

Then based on the table 2 and 3, the erosion and sediment yield maps were classified and vectorized and at last polygons with area less than one hectare because these polygons is not executive, were eliminated and their area was added to their adjacent polygons .To providing suspended load and bed load maps and to calculate suspended load and bed load in each subbasin and work units, at first considering the bed load is twenty percent of suspended load,the sediment yield map was divided by 1.2 and at last suspended load map of basin was obtained and then by subtracting suspended load from total load , bed load was obtained in each pixel . At final step by Spatial Analyst module facilities in the Arc View software and by introducing work units map and hydrologic units map as the background theme, the amount of sediment total load , erosion , suspended load and bed load was obtained in each pixel .
Table2.sediment yield classes in the MPSIAC model

Sediment yield scores	The amount of sediment yield(M3/KM2/Y)	Sediment yield intensity	Sediment yield class
> 100	>1429	Very high	V
75-100	476-1429	High	IV
50-75	238-476	Medium	III
25-50	95-238	Low	II
<25	<95	Very low	I

Table3.Erosion classes

The amount of erosion(M3/KM2/Y)	Erosion intensity	erosion class
>1900	Very high	VI
1300-1900	High	V
1000-1300	Relatively high	IV
615-1000	Medium	III
215-615	Low	II
<215	Very low	I

Table4. PSIAC factors scores in the subbasins

R(sum of factors)	X9	X8	X7	X6	X5	X4	X3	X2	X1	Area(ha)	Kal-e-gorg
46.87	0.00	3.50	14.15	9.92	7.94	4.83	2.52	1.67	2.35	920.14	A1
46.59	0.15	3.74	14.13	9.79	7.45	4.31	2.52	2.72	1.78	1653.50	BO1
R(sum of factors)	X9	X8	X7	X6	X5	X4	X3	X2	X1	Area(ha)	Kal-e-asgir
46.76	0.00	3.50	14.35	9.96	8.13	4.05	2.52	1.67	2.59	1976.99	A2
49.41	0.00	3.50	13.92	9.98	8.13	6.09	2.52	1.67	3.61	426.37	A3
49.80	0.60	4.41	13.46	9.90	5.90	5.30	2.52	6.69	1.03	543.02	A4
41.57	0.24	3.89	7.94	9.93	7.33	4.31	2.52	3.03	2.39	3510.84	BO2
47.30	0.21	3.84	14.04	9.88	7.36	4.31	2.52	2.93	2.20	5165.13	Total

Table5. the mount of sediment yield and erosion in the subbasins

Erosion (m3/km2/y)	SDR	Bed load(m3/km2/y)	Suspended load(m3/km2/y)	Total load(ton/h/y)	Total load(m3/km2/y)	Kal-e-gorg
583.59	0.35	33.80	169.01	2.64	202.81	A1
640.28	0.31	33.47	167.33	2.61	200.79	BO1
Erosion (m3/km2/y)	SDR	Bed load(m3/km2/y)	Suspended load(m3/km2/y)	Total load(ton/h/y)	Total load(m3/km2/y)	Kal-e-asgir
664.45	0.30	33.67	168.33	2.63	201.99	A2
558.27	0.40	36.97	184.83	2.88	221.80	A3
589.82	0.38	37.48	187.41	2.92	224.90	A4
617.88	0.27	28.03	140.16	2.19	168.19	BO2
819.37	0.25	34.32	171.59	2.68	205.91	Total

The providing of work units and erosion shapes maps :
To providing work units, only we used the intersection of geology , geomorphology and hydrologic units (subbasins ) maps and at last because the upper part of this basin is rocky and for executive limitation of tiny units in these region, these units were eliminated and at last 28 work unit were obtained in this basin . By interpretation of aerial photographs and the field surveying, 4 erosion shape in this basin were obtained (these shapes were described in table 6 ).