世界経済・社会統計 = World development indicators

Statistics for Spatial Data.

In this book, Andrew Harvey sets out to provide a unified and comprehensive theory of structural time series models. Unlike the traditional ARIMA models, structural time series models consist explicitly of unobserved components, such as trends and seasonals, which have a direct interpretation. As a result the model selection methodology associated with structural models is much closer to econometric methodology. The link with econometrics is made even closer by the natural way in which the models can be extended to include explanatory variables and to cope with multivariate time series. From the technical point of view, state space models and the Kalman filter play a key role in the statistical treatment of structural time series models. The book includes a detailed treatment of the Kalman filter. This technique was originally developed in control engineering, but is becoming increasingly important in fields such as economics and operations research. This book is concerned primarily with modelling economic and social time series, and with addressing the special problems which the treatment of such series poses. The properties of the models and the methodological techniques used to select them are illustrated with various applications. These range from the modellling of trends and cycles in US macroeconomic time series to to an evaluation of the effects of seat belt legislation in the UK.

Forecasting, Structural Time Series Models and the Kalman Filter

「脆弱性(Vulnerability)」とは何か

The State of Food and Agriculture

Land degradation is occurring in almost all terrestrial biomes and

agro-ecologies, in both low and high income countries. However its impact is

especially severe on the livelihoods of the poor who heavily depend on natural

resources. Despite the severe impact of land degradation on the poor and the crucial

role that land plays in human welfare and development, investments in sustainable

land management (SLM) are low, especially in developing countries. This chapter

summarizes the results from global and regional levels as well as 12 case study

countries. The chapter also draws conclusions and implications for taking action

against land degradation. Land degradation stretches to about 30 % of the total

global land area and about three billion people reside in degraded lands. The annual

global cost of land degradation due to land use/cover change (LUCC) and using

land degrading management practices on static cropland and grazing land is about

300 billion USD. Sub-Saharan Africa (SSA) accounts for the largest share (22 %) of

the total global cost of land degradation. Only about 46 % of the cost of land

degradation due to LUCC which accounts for 78 % of the US$300 billion loss

is borne by land users and the remaining share (54 %) is borne by consumers of

ecosystem services off the farm.

/pdf/economics-of-land-degradation-and-improvement-a-global-3ynbye93i0.pdf

Economics of Land Degradation and Improvement – A Global Assessment for Sustainable Development

Land degradation affects negatively the livelihoods and food security of global population. There have been recurring efforts by the international community to identify the global extent and severity of land degradation. Using the long-term trend of biomass productivity as a proxy of land degradation at global scale, we identify the degradation hotspots in the world across major land cover types. We correct factors confounding the relationship between the remotely sensed vegetation index and land-based biomass productivity, including the effects of inter-annual rainfall variation, atmospheric fertilization and intensive use of chemical fertilizers. Our findings show that land degradation hotpots cover about 29 % of global land area and are happening in all agro-ecologies and land cover types. This figure does not include all areas of degraded lands, it refers to areas where land degradation is most acute and requires priority actions in both in-depth research and management measures to combat land degradation. About 3.2 billion people reside in these degrading areas. However, the number of people affected by land degradation is likely to be higher as more people depend on the continuous flow of ecosystem goods and services from these affected areas. Land improvement has occurred in about 2.7 % of global land area during the last three decades, suggesting that with appropriate actions land degradation trend could be reversed. We also identify concrete aspects in which these results should be interpreted with cautions, the limitations of this work and the key areas for future research.

https://www.econstor.eu/bitstream/10419/106616/1/790810204.pdf

Biomass Productivity-Based Mapping of Global Land Degradation Hotspots

 Adoption of SLM practices is increasing: Fertilizer (47%), Seeds (36%), Intercrop (35%), Crop rotation (24%)  Drivers facilitating SLM adoption include: education, secure land tenure, access to extension, credit, household assets  Constraints to SLM adoption include: inaccessible markets  SLM adoption is agro-ecological and regional (country) specific Figure 2. Biomass productivity decline in Eastern Africa over 1982-2006 Source: Le, Nkonya and Mirzabaev., 2014. Economics of Land Degradation in Eastern Africa

https://www.econstor.eu/bitstream/10419/99988/1/785225005.pdf

Economics of land degradation in Eastern Africa

Conservation agriculture in Central Asia—What do we know and where do we go from here?

Land degradation—defined by the Millennium Ecosystem Assessment report as the long-term loss of ecosystems services—is a global problem, negatively affecting the livelihoods and food security of billions of people. Intensifying efforts, mobilizing more investments and strengthening the policy commitment for addressing land degradation at the global level needs to be supported by a careful evaluation of the costs and benefits of action versus costs of inaction against land degradation. Consistent with the definition of land degradation, we adopt the Total Economic Value (TEV) approach to determine the costs of land degradation and use remote sensing data and global statistical databases in our analysis. The results show that the annual costs of land degradation due to land use and land cover change (LUCC) are about US$231 billion per year or about 0.41 % of the global GDP of US$56.49 trillion in 2007. Contrary to past global land degradation assessment studies, land degradation is severe in both tropical and temperate countries. However, the losses from LUCC are especially high in Sub-Saharan Africa, which accounts for 26 % of the total global costs of land degradation due to LUCC. However, the local tangible losses (mainly provisioning services) account only for 46 % of the total cost of land degradation and the rest of the cost is due to the losses of ecosystem services (ES) accruable largely to beneficiaries other than the local land users. These external ES losses include carbon sequestration, biodiversity, genetic information and cultural services. This implies that the global community bears the largest cost of land degradation, which suggests that efforts to address land degradation should be done bearing in mind that the global community, as a whole, incurs larger losses than the local communities experiencing land degradation. The cost of soil fertility mining due to using land degrading management practices on maize, rice and wheat is estimated to be about US$15 billion per year or 0.07 % of the global GDP. Though these results are based on a crop simulation approach that underestimates the impact of land degradation and covers only three crops, they reveal the high cost of land degradation for the production of the major food crops of the world. Our simulations also show that returns to investment in action against land degradation are twice larger than the cost of inaction in the first six years alone. Moreover, when one takes a 30-year planning horizon, the returns are five dollars per each dollar invested in action against land degradation. The opportunity cost accounts for the largest share of the cost of action against land degradation. This explains why land users, often basing their decisions in very short-time horizons, could degrade their lands even when they are aware of bigger longer-term losses that are incurred in the process.

Alisher Mirzabaev

Papers

Economics of Land Degradation and Improvement – A Global Assessment for Sustainable Development

Biomass Productivity-Based Mapping of Global Land Degradation Hotspots

Economics of land degradation in Eastern Africa

Conservation agriculture in Central Asia—What do we know and where do we go from here?

Global Cost of Land Degradation