AbstractsGeography &GIS

Soil and Water Conservation in the Northern Andes of Peru

by Joachim Krois




Institution: Freie Universität Berlin
Department:
Year: 2016
Posted: 02/05/2017
Record ID: 2133774
Full text PDF: http://edocs.fu-berlin.de/diss/receive/FUDISS_thesis_000000103009


Abstract

This thesis investigates hydro-meteorological boundary conditions in the region of Cajamarca in the northern Andes of Peru and quantifies the impact of selected resource conservation measures on the hydrology of the Ronquillo watershed. The research was undertaken as part of the research project The conservation of water and soil resources in the Chetillano and Ronquillo basins in the Northern Sierra of Peru (CASCUS). The project aims to identify opportunities for enhancing water availability and reducing soil erosion in the region of Cajamarca. This thesis aims to contribute to the CASCUS project by strengthening the knowledge base on hydro-meteorological boundary conditions in the research area. It also seeks to advance the envisioned integrated resource management strategy by quantifying the impact of selected resource conservation measures on the hydrology of the Ronquillo watershed. In order to achieve these objectives, research was undertaken in several stages. Specifically, these stages were: (1) the exploration of the meteorological and hydrological boundary conditions, (2) the development of scenarios for the implementation of resource conservation measures, and (3) the assessment of the hydrological impact of resource conservation measures on the catchment by applying a rainfall-runoff model. The region under investigation is characterized by a complex mountain climate marked by the interaction of a number of meteorological features, including seasonal displacement of the Intertropical Convergence Zone, orographic rainout, rain-bearing mesoscale cloud systems, El Niño Southern Oscillation (ENSO), katabatic drainage flow and local convection, all of which act on different spatial and temporal scales. The Ronquillo watershed displays strong seasonality in stream flow. During the rainy season a large portion of stream flow originates from direct runoff, which drains the watershed rapidly. The main flood formation areas are located in the middle part of the catchment, where soil and land coverage characteristics are most prone to generate surface runoff during strong rainfall. During the dry season a large portion of the discharge of the Ronquillo River originates from the soils covering the high altitude Jalca grasslands. In addition the basement rock aquifers and spring discharge significantly contribute to the dry seasonal discharge. The main objective of the scenario development phase is to provide implementation scenarios for selected soil and water conservation techniques (SWCTs) in the Ronquillo watershed, in order to evaluate their impact on catchment hydrology by applying a rainfall-runoff model. The present study evaluates various implementation scenarios for SWCTs, which fall under the categories “earthworks,” “afforestation,” and “check dam construction.” The earthworks scenarios are developed on the basis of a decision support model. Therefore a multi-criteria evaluation procedure is used that takes into account environmental site assessment criteria such as meteorology, hydrology,…