Applying Hubbert Curves and Linearization to Rock Phosphate

Rock phosphate is a critical, nonrenewable resource for which there is no known substitute in agriculture. Cordell, Drangert, and White (2009) use Hubbert methodology (1956) to estimate the peak--the year after which production will monotonically decline--of world rock phosphate production at 2033-34. This note assesses the applicability of Hubbert’s (1949) peak methodology to world rock phosphate production, based on (a) the ability of the model to produce accurate in-sample and out-of-sample forecasts and stable estimates of ultimately recoverable reserves, and (b) the degree to which the rock phosphate market approximates the theoretical conditions underpinning the Hubbert model. In both respects, the application of Hubbert methodology to rock phosphate is found to be problematic.peak phosphate, Hubbert curves, Hubbert linearization, rock phosphate

Markets vs. Malthus: Food Security and the Global Economy

In the past four years, rising world food prices and the global economic downturn increased the ranks of the world’s food insecure from 848 million to 925 million by September 2010, reversing decades of slow yet steady progress in reducing hunger. While the human costs have been considerable, the political consequences have been significant as well, fueling concerns of two skeptical groups, Neo-Malthusians and food sovereignty advocates. Hendrix assesses the claims of both. On the Neo-Malthusian position, he finds that while population growth and economic development contribute somewhat to price increases, there are few structural, resource-based impediments to increasing aggregate agricultural production. The biggest near-term threats to food security are not dwindling agricultural inputs and agricultural trade, but rather the familiar problems of poverty and political barriers to market access—in particular, the distortions created by agricultural policy in the United States and European Union. A robust trading system is the best way to address current food security problems. In light of forecast changes in global patterns of agricultural productivity, a robust trading system will become even more important to ensuring that a world undergoing climate change will be able to feed itself.

Civil war: is it all about disease and xenophobia? A comment on Letendre, Fincher & Thornhill

Letendre, Fincher &amp; Thornhill (2010) argue that pathogen intensity provides the ultimate explanation for why some countries are more prone to civil war than others. They argue that the economic and political factors highlighted in previous research on civil war are largely caused by underlying differences in pathogen intensity, and contend that disease proneness increases the risk of civil war through its effects on resource competition and xenophobia. They present empirical evidence that they interpret as consistent with their argument: a statistically significant correlation between pathogen intensity and civil war onset. In this comment, we raise concerns over their interpretation of the empirical evidence and their proposed causal mechanisms. We find that the data provide stronger evidence for the reverse causal relationship, namely that civil war causes disease to become more prevalent. This finding is consistent with the literatures on the public health effects of civil war as well as research on state capacity and public health.</jats:p

The West versus Beijing? Determinants of the UN Human Rights Council vote (not) to debate human rights in Xinjiang

This paper addresses the factors shaping the vote of member states on the United Nations Human Rights Council (UNHRC) regarding whether to debate human rights conditions in the Xinjiang Autonomous Region of China. Explanations for the UNHRC’s decision not to debate human rights in Xinjiang fall into three categories: 1) democracy, development, and human rights performance; 2) demographic factors; and 3) security and economic ties to major powers, specifically the United States and China. Bayesian model averaging identifies three factors as robust covariates of the Xinjiang UNHRC vote: liberal democratic domestic institutions, NATO membership, and Chinese arms transfers. Countries with higher democracy scores and NATO member countries were more likely to vote yes, while recipients of Chinese arms transfers were more likely to vote no. In addition to its direct effect, liberal democracy exerts a significant indirect effect via its effect on Chinese arms transfers, with less democratic countries more likely to receive Chinese arms. Participation in the Belt and Road Initiative (BRI) is not a robust correlate when arms transfers are considered. Thus, our analysis lends support to interpreting the vote as a reflection of wider competition between the United States and China but rejects part of the conventional wisdom about how the two countries approach building and mobilizing coalitions in international institutions

Civil war: is it all about disease and xenophobia? A comment on Letendre, Fincher & Thornhill

Letendre, Fincher & Thornhill (2010) argue that pathogen intensity provides the ultimate explanation for why some countries are more prone to civil war than others. They argue that the economic and political factors highlighted in previous research on civil war are largely caused by underlying differences in pathogen intensity, and contend that disease proneness increases the risk of civil war through its effects on resource competition and xenophobia. They present empirical evidence that they interpret as consistent with their argument: a statistically significant correlation between pathogen intensity and civil war onset. In this comment, we raise concerns over their interpretation of the empirical evidence and their proposed causal mechanisms. We find that the data provide stronger evidence for the reverse causal relationship, namely that civil war causes disease to become more prevalent. This finding is consistent with the literatures on the public health effects of civil war as well as research on state capacity and public health

A House Divided: Threat Perception, Regime Factionalism and Repression in Africa

The Ohio State University Mershon Center for International Security StudiesWhy do governments in Africa repress certain contentious challenges but not others? This study adopts a blended approach to studying repression by taking seriously both the characteristics of contentious events as well as nature of the regime in power. We argue that the more threatening a movement is — as measured by the use of violence, opposition demands, and targets — the more likely the state is to use repressive force. However, we relax the assumption that the state is a unitary actor, and allow for the preferences of state leaders and of the security forces to diverge when it comes to carrying out repressive policies. Countries with a history of factionalism in their security forces face an additional challenge: orders to crack down on protesters, rioters, strikers, etc., may not be followed or could even cause police and military forces to defect. We argue this potential is greatest when the challenge is has ethnoreligious aims. We test these propositions using the Social Conflict in Africa Database, and find significant support for our core theoretical conjecture: regimes with a history of past military factionalism are generally less likely to use repression. Such regimes are especially unwilling to repress ethnoreligiously based, ascriptive movements. These results are robust to several estimators that address the hierarchical nature of the event data. These findings demonstrate the benefits of a blended, event-based approach to studying state repression.Mershon Center for International Security StudiesEvent Web Page, Streaming Video, Event Photo

Climate-driven risks to peace over the 21st century

publishedVersio

Armed conflict and fisheries in the Lake Victoria basin

Civil conflict is the most prevalent form of armed conflict in the world today, but this significant driver of food and income security has been largely missing from studies of fisheries. Fisheries conflict is an example of complex dynamics operating in social-ecological systems. We theorize and document the existence of such a feedback loop between conflict in Uganda and fisheries in Lake Victoria. Civil war in northern Uganda resulted in mass human population displacement, which corresponded in time with increases in fishing effort in Lake Victoria. Subsequent changes in catch of Nile perch, the dominant commercial fishery, sparked armed conflict in the lake itself, at Migingo Island, between Uganda and Kenya. From this case study, we draw seven main conclusions. First, these correlation-based relationships are illustrative but not conclusive and we call for further empirical investigation. Second, the couplings between conflict and fishing subsystems are spatially asymmetric: conflict effects are diffuse in their links to broad changes in the fishery, whereas fishery effects may produce more localized conflict events. Third, and most relevant to conflict scholars, the drivers of fishing effort and catch may originate in different subsystems, but their changes and effects must be analyzed in concert. Fourth, the complex and path-dependent impacts of conflicts on natural resources in general, and fisheries in particular, highlights the urgent need for targeted surveys and more mechanistic understanding. Fifth, the open access nature of fisheries in Lake Victoria may exacerbate instabilities not present in other systems. Sixth, the diffuse and context-specific effects of conflicts on fisheries means models of fisheries management (e.g., stock assessment) should not incorporate conflict as a driver at this time. Finally, countries and their stakeholders should focus on diversification in employment for short term coping mechanisms during conflict as a means of short-circuiting the conflict-fisheries feedback loop.U.S. Army Research Office under the Minerva Initiative of the U.S. Department of Defense [W911NF-09-1-007]; National Science Foundation Dynamics of Coupled Natural and Human Systems [1358861]Open Access JournalThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Climate change increases the risk of fisheries conflict

The effects of climate change on the ocean environment – especially ocean warming, acidification, and sea level rise – will impact fish stocks and fishers in important ways. Likely impacts include changes in fish stocks’ productivity and distribution, human migration to and away from coastal areas, stresses on coastal fisheries infrastructure, and challenges to prevailing maritime boundaries. In this paper, we explore these and other related phenomena, in order to assess whether and how the impacts of climate change on fisheries will contribute to the risk of fisheries conflict. We argue that climate change will entail an increase in the conditions that may precipitate fisheries conflict, and thereby create new challenges for existing fisheries management institutions. Several potential changes in fisheries management policy are recommended to avert the growing risk of fisheries-related conflicts

Political opportunity structures, democracy, and civil war

Theories of mobilization suggest that groups are more likely to resort to violence in the presence of political opportunity structures that afford greater prospects for extracting concessions from the government or better opportunities to topple ruling governments. However, existing efforts to consider the possible influences of political opportunity structures on incentives for violence and civil war empirically have almost invariably relied upon measures of democracy to proxy for the hypothesized mechanisms, most notably the argument that the opposing effects of political accommodation and repression will give rise to an inverted U-shaped relationship between democracy and the risk of civil war. The authors detail a number of problems with measures of democracy as proxies for political opportunity structures and develop alternative measures based on the likely risks that political leaders will lose power in irregular challenges and their implications for the incentives for resort to violence. The authors evaluate empirically how the security with which leaders hold office influences the prospects of violent civil conflict. The findings indicate that recent irregular leader entry and transitions indeed increase the risk of conflict onset, while democratic institutions are found to decrease the risk of civil war, after controlling for the new measures of state weakness. </jats:p