ABSTRACT.

Transcription

1 REPORT ON DEMARCATION OF PRIORITY MICRO WATERSHEDS IN 4CIB (LOWER PONNAIYAR UPTO SATHANUR DAM) AND 4CIC (UPPER PONNAIYAR BEYOND SATHANUR DAM) SUBCATCHMENTS (RVP), CHITTOR DISTRICT ANDHRA PRADESH, BANGALORE (RURAL & URBAN) AND KOLAR DISTRICTS, KARNATAKA, CUDDALORE, DHARAMPURI, SALEM, THIRUV ANNAMALAI, VELLORE AND VILLUPURAM DISTRICTS TAMILNADU AND PONDICHERRY ABSTRACT. 1. Survey area :Report On Demarcation Of Priority Micro Watersheds In 4CIB (Lower Ponnaiyar Upto Sathanur Dam) And 4CIC (Upper Ponnaiyar Beyond Sathnur Dam) Subcatchments (RVP), Chittor District Andhra Pradesh, Bangalore (Rural & Urban) And Kolar Districts, Karnataka, Cuddalore, Dharmapuri, Salem, Thiruvannamalai, Vel1ore, and VilIupuram Districts TamiInadu, and PondichelTY. 2. Location 11 37'50" to 13 30'45" N Latitude and 77 32'10" to 79 49'5" Longitude 3. Total area surveyed 15, 17,508 hectares 4. Agro climatic region 10 (semiarid subtropical with excessive evapo-transpiration) 5. Type of survey RR survey for priority delineation 6. Period of survey Base maps 1:50,000 scale survey of India topographic maps 8. Topo-sheet nos. 58 II 1,5,9,13 58M! 1,2, 5, 6, 9, 10, 13, H/9, 10, 13,14 57L/ 1, 2,3,4,5,6,7,8,10,11,12,14,15,16 57!P3,4,8, 57 G110, 11, 12, 14, 15,16, 57KJ 4 9. Hydrological divisions a) Region b) Basin c) Catchment d) Sub catchments e) Watersheds f) Subwatersheds g) Microwatersheds -4-4C -4C1-4C1B& 4CIC - 4C1B1to 4CIB5, and 4C1C1 to 4C1C

2 -11- ] o. SUB WATERSHEDS AND MICROW ATERSm~DS SLNo Water- Number of No of micro Area in SI. No Water- Number of No of Area in sheds Sub water-sheds Hectare sheds Sub micro Hectare watersheds watersheds watersheds I 4ClB] 21 ] C]CI ]8 ]22 ] CIB CIC CIB CIC3 IS III CII CIC C lb CIC Total 77 -t II 4CIC CIC CIC CIC9 ] Total Grand Total Priority categorization SI. Priority. Silt yield index of Micro- Area in ha. Percentage category watersheds I Very high 1200 and above High II 00-II Medium Low Very low Less than Total Soil Erosion hazard SI. Erosion Area in ha. Percentage 2 Slight Erosion Slight to moderate Erosion Moderate Erosion Moderate to severe Erosion Severe Erosion Severe to very severe Erosion Total Miscellaneous Total % 13. Distribution of the area vis a vis land use types SI. Land use category Area Percentage (ha.) I Area under rain fed cultivation Area under irrigated cult!ltin Plantation Crops Barren/Fallow Forest Sparse vegetation/bushy vegetation uncultivated Quarying Total Misc

3 Distribution of soils vis a vis soil texture and erosion categories SI. Textural Slight Slight to Moderate Moderate Severe Severe Misc. Total % classes erosion moderate erosion to severe erosion to very lands area In erosion erosion severe ha. erosion 1 Coarse sand Gravelly fine Moderately fine to fine 4 Moderately fine gravell y i 5 Fine loamy to fine 6 Moderately coarse gravelly 7 Moderately coarse 8 Medimll texture Moderately fine 10 Fine loamy II Fine Moderately - - 5Q tine to coarse 13 Moderately coarse to moderately tine 14 Fine to coarse Moderately fine to loamy Subtotal Miscellaneous Total Distribution of soils ofthe area vis a vis soil depth Sl. Depth Category Area (ha.) Percentage Very Shallow to Shallow Soils I Shallow to moderately deep Soils Moderately deep to 4ep deep to very deep Soils Very deep Soils Total Misc

4 -IV- 16. Distribution of soils of the area vis a vis physiographic position Sl. Physiographic Position Area Percentage (ha.) I River /Streams Sand beaches Delta alluvium/marine alluvium Valley plains Pediplains Pediments Subdued hills Hill Valley Hill side slopes Gullied lands Total Misc Distribution of Soils vis a vis different slope categories Sl. Slope category Area (ha.) Percentage I Nearly level to Very Gently Sloping (0-3 'Yo) Very Gentlv Sloping to Gently Sloping (1-5 %) Gently Sloping to Strongly sloping (1-15 %) Gentlv Sloping to Strongly Sloping (3-10 'Yo) Moderately Sloping Strongly Sloping(5-15 %) Strongly Sloping to Moderately Steep to Steep (10-25 %) Steep to Very Steep (25-50 %) Total Misc Total Distribution of Area in different Priority Categories vis a vis Ditfeent States and its District Districs Very High Medium Low Very Total % SI. State High Low Andra 1 pradesh Chittoor Karnataka Bangalore Karnataka Kolar Tamil nadu Dharmapuri Tamil nadu North Areat Tamil nadu Pondicherry Tamil nadu Salem Tamil nadu South Areot Total

5 -v Distribution of Area in different Priority Categories vis a vis Watersheds Very Very 51. Watersheds High HiQh Medium Low Low Total % 1 4C1B C1B C1B C1B C1B C1C C1C C1C C1C C1C C1C C1C C1C C1C Grand Total Distribution.ofArea in ditterent States and its Districts vis a vis Watersheds AP Pondie Karnataka Tamilnadu herry ci 'c (ij Z L.. Q) :] Q) a a. 0 en.s= 0 0 m I- L..(/J a (ij E Q)-c '5 0> 0 u E :t:: Iii roq) c: c: Iii Q) E a m a.s= (ij - j 0 a.. (J) en z 0 (/) 4C (146) (146) 4C (24) (70) (71) 4C (40) (89) (106) 4C (36) (36) 4C (38t (100) (121) 4C (24) (330) (189) (480) 4C1C (11) (48) (87) (122) 4C1C (106) (3) (116) 4C1C (5) (34) (102) (25) (111) 4C1C (80) (6) (82) 10 (3) 4C1C (1) (175) (175) 4C1C (2) (103) (103) 4C1C (15) (94) (58) (137) 4C1C (117) (23) (34) (139). 4C1C (83) (57) (120) 4C1C (24) (200) (176) (11) (162) (671) (28) (1105) Total (24) (24) (200) (176) (341) (351) (671) (28) (1585)

6 - VI- 21. Extent of area under different erosion intensity mapping units: Sl. EIMUs Area in ha. Percent 1. A CAI CA CA CAS CA CD GI Gl II G G G G G G G G GR G8A R. G GIO GIO GIOA GIO G G12.1O G GIS GI T AI Lt* L7* LTl LT LT LT LT LT LT LT LT Total 13849] Miscellaneous Marshy lands ] ROC Habitation River/stream Tmk M1SC TOTAL