Status and National Priorities of Soil Resources in Sri Lanka

Transcription

1 Status and National Priorities of Soil Resources in Sri Lanka R S Dharmakeerthi President, Soil Science Society of Sri Lanka and W D Wicramasinghe Director, NRMC &Country Focal Point-FAO

2 1. Introduction: Sri Lanka Back ground Land area 6.56 million ha 62 % Agricultural land 20 % Forest Population of 20.2 million Area wise 118 th Population wise 47 th Population density 19 th Showing pressure on land resources Per capita arable land is 0.15 ha Population growth of 1.1% 23 million in 2050

3 1. Introduction: Rainfall and Physiography of Sri Lanka

4 2. Status of Soil Resource First Provisional Soil Map In 1955 Joachim & co-workers published the first provisional soil map of Ceylon Major Features Nature of Parent rock Climate Vegetation Topography Ponnamperuma (1959) Soil classification system for rice growing soils

5 2. Status of Soil Resource Development to Present Status Mostly used soil map & Report by De Alwis & Panabokke 1972 (SSSSL Journal Vol. 2) Mapping units Soil Associations Consisting of Great Soil Groups (Same order Sequence- of genetic horizons) Soil complexes Miscellaneous land units

6 Intermediate Zone 1:400, Status of Soil Resource Soil Maps at Series level

7 2. Status of Soil Resource Fact sheets and Books Fact sheets 3 Rainfall Zones 3 languages

8 Database 2. Status of Soil Resource Database Landscape picture Pedon picture

9 Database 2. Status of Soil Resource Harmonised World Soil Database Preparation of Raster Data Base soil maps of Sri Lanka were digitized and merged to construct the soil map. Soil map of Sri Lanka was generalized. Raster database of soils of Sri Lanka was finalised Preparation of Attribute Data base Attribute data base for top (0-30 cm) and subsoil ( cm) has been constructed Experienced some problems to classify soils using WRB classification system

10 Soil degradation Over 44% of the soil is under some form of degradation!!!

11 Soil Degradation Soil Related Water erosion Nutrient depletion Nutrient / heavy metals accumulation Stalinization Acidification Ground water contamination Acid sulfate soils Loss of arable lands Landslides

12 Soil erosion hazard areas

13 Eroded lands in the Central and Uva Provinces Category Central Province Uva Province Low 20,443 (12%) Moderate 35,638 (21%) High 50,513 (30%) Very high 45,470 (26%) Extremely high Nuwaraeliya Kandy Matale Badulla Monaragala 18,511 (11%) 29,968 (16%) 19,127 (10%) 69,036 (37% 58,932 (31%) 12,097 (6%) 53,148 (26%) 77,567 (38%) 57,751 (29%) 13,472 (7%) 0 (0%) 22,000 (1%) 24,800 (9%) 89,900 (32%) 79,100 (28%) 88,000 (31%) 32,000 (6%) 180,700 (32%) 203,200 (36%) 105,700 (18%) 50,900 (9%) H+VH+EH 325,782 (58%) 617,100 (74%)

14 Fertility decline 61% of arable lands Cultivation of mono crops over 150 years Application of less fertilizers Leaching and erosion losses

15 Fertility decline Conversion of degraded tea lands into vegetable cultivation in steep slopes

16 Acidification In Wet Zone tea growing soils

17 Nutrient accumulation-eutrophication

18 Ground water contamination In north and north west In some areas annual NO 3- -N enrichment rate is 1-2 ppm. About 45% drinking water wells in Vavuniya has over WHO limits

19 Heavy metal contamination-ckdu

20 Salt affected soils 160,000 ha of paddy lands coastal salinity 45,000 ha - inland salinity

21 Acid sulfate soils In south western coastal areas About 10,000 ha of paddy land abandoned Another 45,000ha become less productive (1-2 ton/ha)

22 Loss of arable lands 20-30% of coconut lands paddy lands Roads, buildings, gem mining,

23 landslides Development activities Climate change

24 Soil Degradation Policy and Institutional Issues Lack of a comprehensive database on land management. Inadequate awareness among stakeholders. Lack of technology related skills among farmers. Financial restrictions of farmers for land restoration work. Weak institutional integration. Deficiencies in key institutions. Gaps in policies and the need of strategic plans. Inadequate strength of regulatory services.

25 4. On going activities Promotion of organic fertilizer use Subsidies for soil conservation Protection of Soil Erosion Hazard areas Conducting awareness programs on soil degradation National LADA team Subsidies for chemical fertilizers Classification of Soils in the North and East Developing management strategies for problem soils Site-specific fertilizer application Development of online soil management advisory system

26 5. National priorities Introduce a new Soil Conservation and Land Degradation Prevention Act and implementation Implementation of activities in the NAP Develop a database for soil degradation status for the country Promote organic and bio-fertilizer use Revising fertilizer quality standards Introduction of micro irrigation and rain water harvesting systems Develop a national land use policy

27 The birds that glide the sky and animals that roam the forest Have an equal right to live and move any where in the country, as you have. This land belongs to the people, and all the other living beings; You are only the trustee Arahath Mahinda Thero to King Dvanampiyathissa (B.C. 306)