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41.
Desertification and land degradation are worldwide problems affecting soil, vegetation and the livelihoods of rural populations. Bowal (plural bowé) is a particular form of degraded land that occurs in tropical regions and leads to the exposure of ferricretes, which are unsuitable for farming. Bowé are more common on farmland and degraded savanna. Changes in land use/land cover were used to map a region of 6.7 million ha in northern Benin, West Africa in 1975, 1990 and 2010. The changes observed during these periods (1975–1990, 1990–2010 and 1975–2010) were used to predict the occurrence of bowé in the period up to 2050 using Markovian chain analysis. The results showed a considerable change in land use/land cover during the three periods. The types of land on which bowé occur (farmland and degraded savanna) increased in northern Benin by 5.4% per year during the period 1975–1990 and 9.5% per year during the periods 1990–2010, while the natural vegetation (forest, woodland and tree savanna) decreased by the same amount. The future scenarios also predicted the same trend. In the period 1975–1990, 1.28 million ha (26%) of natural vegetation was converted to degraded savanna and farmland while 2.23 million ha (53%) of natural vegetation was converted to degraded savanna and farmland in the period 1990–2010. Based on the dynamics recorded during the period 1975–1990 and 1990–2010 respectively, a total of 1.28 million ha (26% of the natural vegetation that was present in 1975) and 1.29 million ha (31% of the natural vegetation that was present in 1990) will be converted to farmland and degraded savanna in the study area by 2050.Thus bowalization will persist and increase in the period up to 2050. The natural vegetation could disappear if protection and restoration measures are not taken. It is thus important to take measures to stop the degradation and to implement programs to restore soils on bowé based on the soil and water conservation techniques used on highly degraded West African soils, such as zaï pit and stone rows with grass strips. Some native plants species adapted to bowalization and resistant to climate change in northern Benin (e.g. Asparagus africanus, Andropogon pseudapricus and Combretum nigricans) should be used in association with soil and water conservation techniques on bowé.  相似文献   
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This study investigates the internal migration of black males in South Africa over the period after the formal end of Apartheid using the 1996 census data. The two issues of our primary interests are the following: (i) whether migration patterns of black individuals are consistent with the income‐maximising hypothesis as related to the destination choice; and (ii) whether the redistribution of human capital is detected in internal migration. The results from conditional logit regressions on choices among individuals in 318 districts show that individuals prefer districts with higher expected wages, conditional on other regional characteristics. In addition, there exist differing preferences on the share of population with post‐secondary education by individuals with commensurate educational attainments. Black individuals with post‐secondary education tend to migrate into areas with a higher share of population with post‐secondary education and vice versa, which confirms the divergence of human capital levels across districts.  相似文献   
44.
This article contributes to the debate on the role of land in reducing poverty in rural South Africa. It uses the year of arrival in the former homelands as an instrument for land access and size. This identification strategy is based on the fact that African households were forcibly relocated to the homelands during the apartheid. Due to increasing population pressure, later arrivals were less likely to be assigned land. The results show that land has a large positive effect on household welfare. Because the homelands are relatively disadvantaged areas, these results provide a lower bound for the positive effects of land on household welfare.  相似文献   
45.
It is widely understood that the insurance and banking sectors of every economy perform some functions in driving economic growth. What is not yet well documented is whether their roles are complimentary or substitutive. With the aid of the dynamic panel generalized method of moments (GMM) estimation technique, this paper evaluates the synergistic effect of both sectors on economic growth in a panel of 10 African countries that are responsible for most of the activities in the continent’s financial sector. The insurance-banking-growth nexus was also examined through bootstrap panel causality tests. The results show that the life insurance market and the banking sector, as well as the non-life insurance market and the banking sector, are complimentary. We find that, overall, the relationship between the insurance and banking sectors in Africa is a complimentary one and that their synergistic impact on economic growth is positive. The feedback hypothesis was also confirmed in the relationship between the insurance sector and economic growth and between the banking sector and economic growth.  相似文献   
46.
In this article we specify a model of millet prices in the three West African countries of Burkina Faso, Mali, and Niger. Using data obtained from USAID’s Famine Early Warning Systems Network (FEWS NET) we present a unique regional millet price forecasting model that takes advantage of the panel nature of our data and accounts for the distance of rural markets from capital cities. Another novel aspect of our analysis is our use of the Normalized Difference Vegetation Index (NDVI) to detect and control for variation in conditions for productivity. We find that including NDVI information significantly improves price forecasts.  相似文献   
47.
We investigate whether smallholder horticultural commercialization is able to, as often stipulated, reduce poverty in developing countries with the help of panel household survey data from Kenya. We find evidence for a positive association between vegetable commercialization and household welfare, even when controlling for unobserved heterogeneity across households. Interestingly, the effect differs depending on which market vegetables are being produced for: commercialization through the export market is consistently positively associated with income but not wealth, while there is some limited evidence for commercialization through the domestic market channel being positively related to welfare measured by asset holdings and income, depending on the specification.  相似文献   
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49.
This paper empirically assesses if and to what extent cross-country differences in institutions inherited from the past affect current institutional quality in Africa. Specifically, the work evaluates if legal origins and disease endowments explain cross-country differences in the quality of contemporary institutions that are widely considered to be important for financial system development and other economic outcomes, such as those related to creditor rights protection and the credit information infrastructure, as well as the judicial, legal property and insolvency systems. Empirical tests are carried out on a sample of 46 African former European colonies with data on current institutional quality from 2004 to 2013. The findings reveal that the legal origins hypothesis receives strong support in the data: historical factors, rooted in legal origins, have long-lasting effects on current institutional quality in the African context. Mixed evidence is instead found for the endowment view.  相似文献   
50.
While the literature on business power and global finance has illuminated the ways in which financial institutions limit the policy autonomy of states in developing countries, we know much less about the circumstances under which the power of financiers is undermined. In this article, I advance explanations of these circumstances by arguing that state access to natural resource revenues reduces the power of financial institutions and enhances the capacity of the state to pursue central bank policies which violate the interests of major financiers. I employ a case study of central bank policy in Nigeria to probe this argument and find evidence that supports the claim that whenever the Nigerian government's access to resource revenues increased, the state's capacity to diverge from financiers’ preferred central bank policies and to advance its own preferences increased as well. The analysis provides the basis for broader propositions about the policy space of developing countries vis-à-vis financial institutions and the variability of structural power.  相似文献   
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