11 research outputs found
Effects of land titling and registration on tenure security and agricultural investments: Case of Gataraga sector, Northern Rwanda
Rwanda has undertaken a land registration and titling program since 2008 with a registration of 10.3 million land parcels in 2013. The aim of this paper is to investigate the early effects of the program on tenure security and agricultural investments since few studies have been carried out in this research area. The study was undertaken in Musanze district in Northern Rwanda, with specific focus on Gataraga sector and it draws on a mix of qualitative and quantitative research methods. The findings indicate that the program led to reduced land conflicts and improved tenure security. Further, it had resulted in increasing collateral value of land; however mortgaging land to access loans seemed to depend on various factors including demographic and socio-economic characteristics of households. Land rental was the most common form of land market and the relatively well-off farmers seemed to gain most from the program than the poorest farmers
The accuracy of drainage network delineation as a function of environmental factors: A case study in Central and Northern Sweden
Drainage networks delineated from Digital Elevation Models (DEMs), are the basis for the modelling of geomorphological and hydrological processes, biogeochemical cycling, and water resources management. Besides providing effective models of water flows, automatically extracted drainage networks based on topography can diverge from reality to varying degrees. The variability of such disagreement within catchments has rarely been examined as a function of the heterogeneity of land cover, soil type, and slope in the catchment of interest. This research gap might not only substantially limit our knowledge of the uncertainty of hydrological prediction, but can also cause problems for users attempting to use the data at a local scale. Using 1:100000 scale land cover maps, Quaternary deposits maps, and 2 m resolution DEMs, it is found that the accuracy of delineated drainage networks tends to be lower in areas with denser vegetation, lower hydraulic conductivity, and higher erodibility. The findings of this study could serve as a guide for the more thoughtful usage of delineated drainage networks in environmental planning, and in the uncertainty analysis of hydrological and biochemical predictions. Therefore, this study makes a first attempt at filling the knowledge gap described above
Remote sensing for forest management in semi-arid environments
The aim of the study is to (i) evaluate a method, based on the normalized difference vegetation index (NDVI) calculated from Landsat TM data, for estimation of tree canopy cover in semi-arid environments and (ii) determine canopy cover changes in a forest area in the Sudan by applying the method on Landsat MSS data from 1972 and 1979. Primarily, the NDVI based method was applied on NDVI values, calculated from corrected Landsat TM scene from 1987. The output of the applied model was a continuous canopy cover map. The result was compared to field data from 1989. The total accuracy is above 70 per cent for the classified areas. To determine canopy cover changes from 1972 to 1987 the Landsat TM scene was complemented by two Landsat MSS scenes from 1972 and 1979. The same regression model as in the first part of the study was applied on the scenes. Between 1972 and 1979 an increase, from 60 per cent to 76 per cent, in mean canopy cover was determined. In 1987 the mean canopy cover was only 16 per cent
EFFECTS OF LAND TITLING AND REGISTRATION ON TENURE SECURITY AND AGRICULTURAL INVESTMENTS: CASE OF GATARAGA SECTOR, NORTHERN RWANDA
Rwanda has undertaken a land registration and titling program since 2008 with a registration of 10.3 million land parcels in 2013. The aim of this paper is to investigate the early effects of the program on tenure security and agricultural investments since few studies have been carried out in this research area. The study was undertaken in Musanze district in Northern Rwanda, with specific focus on Gataraga sector and it draws on a mix of qualitative and quantitative research methods. The findings indicate that the program led to reduced land conflicts and improved tenure security. Further, it had resulted in increasing collateral value of land; however mortgaging land to access loans seemed to depend on various factors including demographic and socio-economic characteristics of households. Land rental was the most common form of land market and the relatively well-off farmers seemed to gain most from the program than the poorest farmers
Land-use planning for sustainable urban development in africa : A spatial and multi-objective optimization approach
Land-use planning, which requires finding a balance among different conflicting social, economic and environment factors, is a complex task needed everywhere, including Africa. One example is the city of Zanzibar in Tanzania, which is under special consideration for land-use revision. From one side, the city has high potentials for tourist industry and at the other side there are major challenges with the city structure and poor accessibilities. In order to prepare a proper land-use plan for the city, a variety of influencing conflicting factors needs to be considered and satisfied. This can be regarded as a common problem in many African cities, which are under development. This paper aims to address the problem by proposing and demonstrating the use of Geographical Information System (GIS) and multi-objective optimization for land-use planning, in Zanzibar as a case study. The measures which have been taken by Zanzibar government to address the development challenges through the Zanzibar Strategy for Growth and Reduction of Poverty (ZSGRP) were identified by studying related documents and interviewing experts. Based on these, two objective functions were developed for land-use planning. Optimum base land-use plans were developed and mapped by optimizing the objective functions using the NSGA-II algorithm. The results show that the proposed approach and outputs can considerably facilitate land-use planning in Zanzibar. Similar approaches are highly recommended for other cities in Africa which are under development
Sustainable and Resilient Land Use Planning: A Multi-Objective Optimization Approach
Land use allocation (LUA) is of prime importance for the development of urban sustainability and resilience. Since the process of planning and managing land use requires balancing different conflicting social, economic, and environmental factors, it has become a complex and significant issue in urban planning worldwide. LUA is usually regarded as a spatial multi-objective optimization (MOO) problem in previous studies. In this paper, we develop an MOO approach for tackling the LUA problem, in which maximum economy, minimum carbon emissions, maximum accessibility, maximum integration, and maximum compactness are formulated as optimal objectives. To solve the MOO problem, an improved non-dominated sorting genetic algorithm III (NSGA-III) is proposed in terms of mutation and crossover operations by preserving the constraints on the sizes for each land use type. The proposed approach was applied to KaMavota district, Maputo City, Mozambique, to generate a proper land use plan. The results showed that the improved NSGA-III yielded better performance than the standard NSGA-III. The optimal solutions produced by the MOO approach provide good trade-offs between the conflicting objectives. This research is beneficial for policymakers and city planners by providing alternative land use allocation plans for urban sustainability and resilience
Variabilities and trends of rainfall, temperature, and river flow in sipi sub-catchment on the slopes of mt. Elgon, uganda
The variabilities in rainfall and temperature in a catchment affect water availability and sustainability. This study assessed the variabilities in rainfall and temperature (1981–2015) and river flow (1998–2015) in the Sipi sub-catchment on annual and seasonal scales. Observed daily rainfall and temperature data for Buginyanya and Kapchorwa weather stations were obtained from the Uganda National Meteorological Authority (UNMA), while the daily river-flow data for Sipi were obtained from the Ministry of Water and Environment (MWE). The study used descriptive statistics, the Standardized Precipitation Index (SPI), Mann–Kendall trend analysis, and Sen’s slope estimator. Results indicate a high coefficient of variation (CV) (CV > 30) for August, September, October, and November (ASON) seasonal rainfall, while annual rainfall had a moderate coefficient of variation (20 ˂ CV ˂ 30). The trend analysis shows that ASON minimum and mean temperatures increased at α = 0.001 and α = 0.05 levels of significance respectively in both stations and over the entire catch-ment. Furthermore, annual and March, April, and May (MAM) river flows increased at an α = 0.05 level of significance. A total of 14 extremely wet and dry events occurred in the sub-catchment during the post-2000 period, as compared to five in the pre-2000. The significant increased trend of river flow could be attributed to the impacts of climate and land-use changes. Therefore, future studies may need to quantify the impacts of future climate and land-use changes on water resources in the sub-catchment
Carbon budget estimation of a subarctic catchment using a dynamic ecosystem model at high spatial resolution
A large amount of organic carbon is stored in high latitude soils. A substantial proportion of this carbon stock is vulnerable and may decompose rapidly due to temperature increases that are already greater than the global average. It is therefore crucial to quantify and understand carbon exchange between the atmosphere and subarctic/arctic ecosystems. In this paper, we combine an Arctic-enabled version of the process-based dynamic ecosystem model, LPJGUESS (version LPJG-WHyMe-TFM) with comprehensive observations of terrestrial and aquatic carbon fluxes to simulate long-term carbon exchange in a subarctic catchment at 50 m resolution. Integrating the observed carbon fluxes from aquatic systems with the modeled terrestrial carbon fluxes across the whole catchment, we estimate that the area is a carbon sink at present and will become an even stronger carbon sink by 2080, which is mainly a result of a projected densification of birch forest and its encroachment into tundra heath. However, the magnitudes of the modeled sinks are very dependent on future atmospheric CO2 concentrations. Furthermore, comparisons of global warming potentials between two simulations with and without CO2 increase since 1960 reveal that the increased methane emission from the peatland could double the warming effects of the whole catchment by 2080 in the absence of CO2 fertilization of the vegetation. This is the first process-based model study of the temporal evolution of a catchment-level carbon budget at high spatial resolution, including both terrestrial and aquatic carbon. Though this study also highlights some limitations in modeling subarctic ecosystem responses to climate change, such as aquatic system flux dynamics, nutrient limitation, herbivory and other disturbances, and peatland expansion, our study provides one process-based approach to resolve the complexity of carbon cycling in subarctic ecosystems while simultaneously pointing out the key model developments for capturing complex subarctic processes