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The emergence of satellite sensors that can routinely observe millions of individual smallholder farms raises possibilities for monitoring and understanding agricultural productivity in many regions of the world. Here we demonstrate the potential to track smallholder maize yield variation in western Kenya, using a combination of 1-m Terra Bella imagery and intensive field sampling on thousands of fields over 2 y. We find that agreement between satellite-based and traditional field survey-based yield estimates depends significantly on the quality of the field-based measures, with agreement highest (R2 up to 0.4) when using precise field measures of plot area and when using larger fields for which rounding errors are smaller. We further show that satellite-based measures are able to detect positive yield responses to fertilizer and hybrid seed inputs and that the inferred responses are statistically indistinguishable from estimates based on survey-based yields. These results suggest that high-resolution satellite imagery can be used to make predictions of smallholder agricultural productivity that are roughly as accurate as the survey-based measures traditionally used in research and policy applications, and they indicate a substantial near-term potential to quickly generate useful datasets on productivity in smallholder systems, even with minimal or no field training data. Such datasets could rapidly accelerate learning about which interventions in smallholder systems have the most positive impact, thus enabling more rapid transformation of rural livelihoods.

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Proceedings of the National Academy of Sciences of the United States of America
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David Lobell
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Temperature data are commonly used to estimate the sensitivity of many societally relevant outcomes, including crop yields, mortality, and economic output, to ongoing climate changes. In many tropical regions, however, temperature measures are often very sparse and unreliable, limiting our ability to understand climate change impacts. Here we evaluate satellite measures of near-surface temperature (Ts) as an alternative to traditional air temperatures (Ta) from weather stations, and in particular their ability to replace Ta in econometric estimation of climate response functions. We show that for maize yields in Africa and the United States, and for economic output in the United States, regressions that use Ts produce very similar results to those using Ta, despite the fact that daily correlation between the two temperature measures is often low. Moreover, for regions such as Africa with poor station coverage, we find that models with Ts outperform models with Ta, as measured by both R 2 values and out-of-sample prediction error. The results indicate that Ts can be used to study climate impacts in areas with limited station data, and should enable faster progress in assessing risks and adaptation needs in these regions.

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Environmental Research Letters
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Sam Heft-Neal
David Lobell
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Stanford researchers view ocean management as next front for China to compete as global sustainability leaders.

As global fish stocks continue sinking to alarmingly low levels, a joint study by marine fisheries experts from within and outside of China concluded that the country’s most recent fisheries conservation plan can achieve a true paradigm shift in marine fisheries management – but only if the Chinese government embraces major institutional reform.

The researchers, led by Stanford University’s Ling Cao and Rosamond Naylor, published their perspective piece “Opportunity for Marine Fisheries Reform in China,” in the Proceedings of the National Academy of Sciences of the United States of America.

The researchers examined the history of Chinese government priorities, policies, and outcomes related to marine fisheries since China’s 1978 Economic Reform, and examined how its leaders’ agenda for “ecological civilization” could successfully transform marine resource management in the coming years.

“The goal of our research was to explore the opportunities for marine fisheries reform in China that arise from their 13th Five-Year Plan and show how the best available science can be used in the design and implementation of fisheries management in China's coastal and ocean ecosystems,” said Cao, a Research Scholar with Stanford’s Center on Food Security and the Environment (FSE) and Shanghai Jiao Tong University.

The most recent plan provides a policy platform for the protection of marine ecosystems and the restoration of fisheries within China’s exclusive economic zone – an area of coastal water and seabed to which China claims exclusive rights for fishing, drilling, and other economic activities. They found that while China has attempted to reverse the trend of declining fish stocks in the past, serious institutional reforms are needed to achieve a true shift in marine fisheries management. The authors recommend new institutions for science-based fisheries management, secure fishing access, policy consistency across provinces, educational programs for fisheries managers, and increasing public access to scientific data.

The paper emphasizes the cultural norms that underpin China’s fisheries management – norms that are often overlooked and misunderstood by Western scientists. “China will follow its own cultural norms in governing its fisheries resources,” observed Roz Naylor, FSE Director and William Wrigley Professor in Earth System Science at Stanford University. “Understanding cultural differences will promote a stronger international community in marine science and sustainable fisheries management.”

As China accounts for almost one-fifth of global catch volume, it has made great efforts to carry out conservation and management of fisheries resources by adopting and practicing various measures over the past three decades. The government is introducing a series of new programs for sustainable fisheries and aquaculture, with greater traceability and accountability in marine resource management and area controls on coastal development. The most recent plan notably includes marine ecosystem protection as a significant component of the central government’s environmental agenda.

The timing of this research comes at a unique phase in China’s fisheries conservation strategy as they recently introduced specific goals for both the Ocean and Fisheries Five-Year Plans. “The Chinese government is poised to take serious action on marine ecosystem management,” Cao said. “Time is of the essence.”

Although the paper’s authors view China’s efforts as a signal of dedication toward furthering fisheries conservation, they hope their perspective paper helps highlight the need for true institutional reform in order to see the Chinese government’s goals realized.

 “Fisheries management and resource conservation is a complex undertaking. To rebuild China's depleted fisheries, serious institutional reforms are needed. The road ahead is still long,” said co-author Yingqi Zhou from Shanghai Ocean University.

 

Ling Cao is a research scholar with the Center on Food Security and the Environment, and a faculty member of the Institute of Oceanography at Shanghai Jiaotong University.

Rosamond Naylor is the director of the Center on Food Security and the Environment, William Wrigley Professor of Earth System Science at Stanford and a senior fellow at the Freeman Spogli Institute for International Studies.

The translated Chinese version titled "Marine Fisheries Reform in Our Country: Review and Recommendations" can be found at China Ocean News.

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Abstract: Globally, infectious diseases are emerging at an increasing rate. Vector-borne diseases in particular present one of the biggest threats to public health globally. Many of these diseases are zoonotic, meaning they cycle in animal populations but can spillover to infect humans. As a result, risk to humans of acquiring a zoonotic or vector-borne disease largely depends on the distribution and abundance of the reservoir hosts—the species of animals that pathogens naturally infect—as well as of the vector species. The ecology of many reservoir hosts and vectors is rapidly changing due to global change, which will fundamentally alter human disease risk in as yet unforeseen ways. In this talk, I will present and discuss three lines of research aimed at identifying drivers of disease emergence and risk at multiple spatial scales including 1) the ecological and environmental drivers of Lyme disease in California, 2) the roles of human behavior and land use in driving human Lyme disease in the northeastern US, and 3) effects of deforestation, land use policy and socio-ecological feedbacks in driving malaria in the Brazilian Amazon.

About the Speaker: Andrew MacDonald is a disease ecologist and a National Science Foundation Postdoctoral Fellow in Biology at Stanford University. He received his PhD from the Department of Ecology, Evolution and Marine Biology at the University of California, Santa Barbara in September 2016. His dissertation focused on the effect of land use and environmental change on tick-borne disease risk in California and the northeastern US. His current work focuses on coupled natural-human system feedbacks and land use change as drivers of mosquito-borne disease, with a focus on malaria in the Amazon basin.

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The Stanford Center at Peking University (SCPKU) held its second annual Lee Shau Kee World Leaders Forum at the center on Oct 13.  This year’s conference, titled “Climate Change and Clean Energy,” was keynoted by Dr. Steven Chu, the William R. Kenan, Jr., Professor of Physics and Professor of Molecular and Cellular Physiology in the Medical School at Stanford University; the 12th U.S. Secretary of Energy; and co-recipient of the 1997 Nobel Prize in Physics for laser cooling and atom trapping.  Two panel discussions with a diverse set of experts from academia, government, and industry were also part of the event.

After welcoming remarks by SCPKU Director Jean C. Oi and Xiamen University Dean of the School of Energy Research Ning Li, the conference kicked off with the first panel, “Paths to Clean Energy” which centered around two questions:  Is renewable energy feasible and how does China move away from coal as a dominant energy source?  The second panel, “Challenges and Opportunities to Clean Energy,” focused on barriers preventing China from being progressive on climate change.   China’s National Energy Advisory Committee, British Petroleum-China, and the U.S. Commission on Natural Resources Protection were among the organizations represented by panelists.

 

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Panelists discuss climate change and clean energy at SCPKU's World Leaders Forum held October 13.
Courtesy of Stanford University

 

Steven Chu’s keynote wrapped up the forum, which touched on new data reflecting the risks of climate change and the need to continue progress on the development of clean energy.  Regarding the pressing issue of pollution, he cited data from a British study inferring that the risk of contracting lung cancer is 29x higher in Beijing than other cities and highlighted Stanford’s research on nano-fiber filtration as a possible solution.  Chu also spoke on the topic of energy storage and how the full cost of renewable energy needs to account for backup generation capacity, transmission and distribution systems, as well as the storage itself.  Two things, he said, will likely play large roles in the future: high voltage lines (HVDC), and machine learning, which will be needed for largely autonomous management of the electrical grid.  Nuclear energy will also be important to mitigate blackouts when transitioning to clean energy.  In closing, Chu shared a poignant phrase from ancient Native Americans: “We do not inherit the land from our ancestors, we borrow it from our children.” 
 

The purpose of the forum is to raise public understanding of the complex issues China and other countries face in the course of development.  Funded by a generous gift from the Lee Shau Kee Foundation, the forum seeks to increase support for Asia-Pacific cooperation and turn ideas into action.  

 

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Steven Chu poses with SCPKU World Leaders Forum attendees after delivering keynote.
Courtesy of Stanford University

 

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Reception following SCPKU's World Leaders Forum featuring the China National Symphony Orchestra Concert Quartet in
the center's courtyard.
Courtesy of Stanford University

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Steven Chu keynotes SCPKU's second World Leaders Forum.
Stanford University
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Beth Duff-Brown
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Stanford researchers have determined that more than 15 million children are living in high-mortality hotspots across 28 Sub-Saharan African countries, where death rates remain stubbornly high despite progress elsewhere within those countries.

The study, published online Oct. 25 in The Lancet Global Health, is the first to record and analyze local-level mortality variations across a large swath of Sub-Saharan Africa.

These hotspots may remain hidden even as many countries are on track to achieve one of the U.N. Sustainable Development Goals: reducing the mortality rate of children under 5 to 25 per 1,000 by 2030. National averages are typically used for tracking child mortality trends, allowing left-behind regions within countries to remain out of sight — until now.

The senior author of the study is Eran Bendavid, MD, MS, an assistant professor of medicine and core faculty member at Stanford Health Policy. The lead author is Marshall Burke, PhD, an assistant professor of Earth System Science and a fellow at the Freeman Spogli Institute’s Center on Food Security and the Environment.

Decline in under-5 mortality rate

The authors note that the ongoing decline in under-5 mortality worldwide ranks among the most significant public and population health successes of the past 30 years. Deaths of children under the age of 5 years have fallen from nearly 13 million a year in 1990 to fewer than 6 million a year in 2015, even as the world’s under-5 population grew by nearly 100 million children, according to the Institute for Health Metrics and Evaluation.

“However, the amount of variability underlying this broad global progress is substantial,” the authors wrote.

“Mortality numbers are typically tracked at the national level, with the assumption that national differences between countries, such as government spending on health, are what determine progress against mortality,” Bendavid said. “The goal of our work was to understand whether national-level mortality statistics were hiding important variation at the more local level — and then to use this information to shed light on broader mortality trends.”

The authors used data from 82 U.S. Agency for International Development surveys in 28 Sub-Saharan African countries, including information on the location and timing of 3.24 million births and 393,685 deaths of children under 5, to develop high-resolution spatial maps of under-5 mortality from the 1980s through the 2000s.

Using this database, the authors found that local-level factors, such as climate and malaria exposure, were predictive of overall patterns, while national-level factors were relatively poor predictors of child mortality.

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Temperature, malaria exposure, civil conflict

“We didn’t see jumps in mortality at country borders, which is what you’d expect if national differences really determined mortality,” said co-author Sam Heft-Neal, PhD, a postdoctoral scholar in Earth System Science. “But we saw a strong relationship between local-level factors and mortality.”

For example, he said, one standard deviation increase in temperature above the local average was related to a 16-percent higher child mortality rate. Local malaria exposure and recent civil conflict were also predictive of mortality.

The authors found that 23 percent of the children in their study countries live in mortality hotspots — places where mortality rates are not declining fast enough to meet the targets of the U.N. Sustainable Development Goals. The majority of these live in just two countries: Nigeria and the Democratic Republic of Congo. In only three countries do fewer than 5 percent of children live in hotspots: Benin, Namibia and Tanzania.

As part of the research, the authors have established a high-resolution mortality database with local-level mortality data spanning the last three decades to provide “new opportunities for a deeper understanding of the role that environmental, economic, or political conditions play in shaping mortality outcomes.”  The database, available at http://fsedata.stanford.edu, is an open-source tool for health and environmental researchers, child-health experts and policymakers.

“Our hope is that the creation of a high-resolution mortality database will provide other researchers new opportunities for deeper understanding of the role that environmental, economic or political conditions play in shaping mortality outcomes,” said Bendavid.  “These data could also improve the targeting of aid to areas where it is most needed.”

The research was supported by a grant from the Stanford Woods Institute for the Environment

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An HIV positive mother of six boys and one girl, poses with her children in her shelter in Juba on April 28, 2016. According to UN AIDS, nearly 3% of the adult population in South Sudan is HIV positive, with 13,000 deaths every year and 18,000 new infections annually. However, these figures should be likely higher if there was a more accurate evaluation among the rural population.
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China’s recent initiatives to deepen health reform, control antimicrobial resistance, and strengthen primary health services are the topics of ongoing collaborative research by the Asia Health Policy Program (AHPP) at Stanford’s Shorenstein Asia-Pacific Research Center and Chinese counterparts. For example, with generous support from ACON Biotechnology and in partnership with the ACON Biotech Primary Care Research Center in Hangzhou, China, AHPP hosts an annual conference on community health services and primary health care reform in China.

The conference, titled Forum on Community Health Services and Primary Health Care Reform, was held in June at the Stanford Center at Peking University (SCPKU) in Beijing. It featured distinguished policymakers, providers and researchers who discussed a wide-range of topics from China’s emerging “hierarchical medical system” for referring patients to the appropriate level of care (fenji zhenliao), as well as the practice and challenges of innovative approaches to primary care and integrated medical care systems. Yongquan Chen, director of Yong’an City Hospital and representative for the mayor’s office of Sanming, talked about health reforms in Sanming City, Fujian Province, a famous example within China. He discussed the incentives and reasoning behind the reforms, which focus on removing incentives for over-prescription of medications, demonstrating government leadership for comprehensive reforms, consolidating three agencies into one, monitoring implementation and easing tensions between doctors and patients. He pointed out the feasibility and early successes of reform by comparing public hospitals in the city in terms of their revenues and costs, reduced reliance on net revenue from medication sales, and other dimensions of performance. Finally, he addressed reform implementation and future plans on both the hospital's and the government's part.

Xiaofang Han, former director of the Beijing Municipal Development and Reform Commission, shared her personal views on the challenges patients face in navigating China’s health system (kan bing nan) and the need to improve the structure of the delivery system, including a revision to the incentives driving over-prescription in China’s fee-for-service payment system. She emphasized that patients’ distrust of primary care providers can only be overcome by demonstrating improved quality (e.g. with a systematic training program for general practitioners, GPs), and that referral systems should be based on the actual capabilities of the clinicians, not their formal labels. To reach China’s goal of over 80 percent of patients receiving management and first-contact care within their local communities will require improved training and incentive programs for newly-minted MDs, a more flexible physician labor market, and innovations in e-health and patient choice regarding gatekeeping or “contract physician services” (qianyue fuwu).        

Guangde County People's Hospital Director Mingliang Xu spoke about practices and exploration of healthcare alliances and initiatives to provide transparent incentives linking medical staff bonuses to metrics of quality. Ping Zhu from Community Healthcare Service Development and Research Center in Ningbo addressed building solid relationships between doctors and residents and providing more patient-centered services.        

Professor Yingyao Chen from Fudan University School of Public Health discussed performance assessment of community health service agencies based on his research in Shanghai. He introduced the strengths and weaknesses of the incentives embedded in the assessment system for China’s primary care providers, and concluded with suggestions for future research. Dr. Linlin Hu, associate professor at Peking Union Medical College, discussed China's progress and challenges of providing universal coverage of national essential public health services.

Professor Hufeng Wang of Renmin University of China discussed China’s vision for a “hierarchical medical system”– bearing resemblance to “integrated care,” “managed care,” or NHS-like coordination of primary and specialized care – with examples of pilot reforms from Xiamen, Zhenjiang and Dalian cities. Dr. Zuxun Lu, professor of Tongji Medical College of Huazhong University of Science and Technology, also discussed hierarchical medical systems and declared that China currently had a “discounted gatekeeper system.”

Dr. Yaping Du of Zhejiang University presented his research on mobile technology for management of lipid levels and with the help of a volunteer, demonstrated “Dyslipidemia Manager,” a mobile app-based product for both patients and doctors. Innovative strategies for primary prevention of cardiovascular diseases in low- and middle-income countries were the focus of remarks by Dr. Guanyang Zou from the Institute for Global Health and Development at Queen Margaret University, including its connections to international experiences with China’s current efforts in that area.  

In sum, the 2016 Forum elicited lively, evidence-based discussions about the opportunities and challenges in improving primary care and sustaining universal coverage for China.  Plans are underway for convening the third annual ACON Biotech-Stanford AHPP Forum on Community Health Services and Primary Health Care Reform in June 2017 at SCPKU. Anyone with original research or innovative experiences with primary care in China may contact Karen Eggleston regarding participation in next year’s Forum. 

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Policymakers, healthcare providers and researchers gathered at Stanford Center at Peking University to discuss community health services and primary healthcare reform, Beijing, June 2016.
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India is one of the world's largest food producers, making the sustainability of its agricultural system of global significance. Groundwater irrigation underpins India's agriculture, currently boosting crop production by enough to feed 170 million people. Groundwater overexploitation has led to drastic declines in groundwater levels, threatening to push this vital resource out of reach for millions of small-scale farmers who are the backbone of India's food security. Historically, losing access to groundwater has decreased agricultural production and increased poverty. We take a multidisciplinary approach to assess climate change challenges facing India's agricultural system, and to assess the effectiveness of large-scale water infrastructure projects designed to meet these challenges. We find that even in areas that experience climate change induced precipitation increases, expansion of irrigated agriculture will require increasing amounts of unsustainable groundwater. The large proposed national river linking project has limited capacity to alleviate groundwater stress. Thus, without intervention, poverty and food insecurity in rural India is likely to worsen.

 

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