Information
Level 2 detail of experimental conditions (what might be found in a journal paper or project brief in Hydstra)
Description of study
What?
Runoff, erosion and nutrient losses were measured from twelve plots, comprising of four treatments and three crop combinations. Each plot was 19 m long and 8 m wide. Natural slope of these plots ranged from 35 to 44%, with an average of 42%.
When and Where?
The study commenced in 1995 to 1998 in Victory in Manupali watershed, Philippines. 124º47E AND 7º57N.
The soil parent materials were thick deposits of siliceous volcanic ejecta either deposited in place or transported from upslope as colluvial or alluvial materials. Loamy sand soils dominate the area.
How?
The four treatments included:
- Traditional up-down planting;
- Planting on the contours;
- Planting vegetable up-and-down the slope with strips of bean crop across the slope; and
- Planting vegetables up-and-down the slope, but with four hedgerows of high value crops planted on the contour from top to bottom at 4 m intervals.
For each management practice a sequence of tomato, cabbage and corn was planted, with approximately three crops planted per year on each plot. Tomatoes were planted in a single row system with 1.5 m and 0.4 m spacing between and within rows. Cabbage was planted in a paired-row system, with 0.8 m between bed centers and 0.35 m plant spacing within and between rows on the bed. Corn plant spacing was 0.75 m between and 0.25 m within rows, as was plant spacing for the beans.
Asparagus and other high value hedgerow crops were planted in a triangular fashion with an alternating double row system. Initial cultivation, with a single share mouldboard plow, was by draft animal. All other cultivations and tillage practices were done manually by grub hoes.
Crop cover was measured by quadrats (0.7 m long by 0.3 m wide) at the top, middle and the bottom of each erosion-runoff plot. In each slope position, crop cover was measured within and between crop rows.
After each rain event eroded soil was collected from galvanised iron sheets 22.5cm above and 20cm below the ground surface, air-dried, and weighed. Collected sediment was also analysed for organic C, pH, Ca, Mg, P, K, S and total N.
Runoff was directed to a series of collection barrels, where the volume of runoff was measured for every event and analysed for NO3-.
Site identifier code: na
Principal investigator: Poudel DD
Principal data manager: -na
Principal organizations: na
Data custodian: na
Key co-operators: -na
Data access policy: Data not accessible.
Planned pathway for data: completed study (there is no evidence of formal database records)
Data warehousing: for ongoing studies -na
Planned data upload frequency: for ongoing studies –na
Key references and sources of this data synthesis
Poudel DD, Midmore DJ, West LT. 1999. Erosion and productivity of Vegetable Systems on sloping volcanic ash-derived Philippine soil.
Key words
Runoff, water quality, horticulture