The impact of population growth and climate change on food security in Africa: looking ahead to 2050

Providing nutritious and environmentally sustainable food to all people at all times is one of the greatest challenges currently facing society. This problem is particularly acute in Africa where an estimated one in four people still lack adequate food to sustain an active and healthy life. In this study, we consider the potential impact of future population growth and climate change on food security in Africa, looking ahead to 2050. A modelling framework termed FEEDME (Food Estimation and Export for Diet and Malnutrition Evaluation) was used which was characterized to model the impacts of future climate changes (utilizing the Intergovernmental Panel on Climate Change Special Report on Emissions Scenarios projections) and projected population growth on food availability and subsequent undernourishment prevalence in 44 African countries. Our results indicate that projected rapid population growth will be the leading cause of food insecurity and widespread undernourishment across Africa. Very little to no difference in undernourishment projections were found when we examined future scenarios with and without the effects of climate change, suggesting population growth is the dominant driver of change. Various adaptation options are discussed, such as closing the yield gap via sustainable intensification and increasing imports through trade and aid agreements. These strategies are likely to be critical in preventing catastrophic future food insecurity.     

The Adoption of Genetically Modified Cotton and Poverty Reduction in Pakistan

This article employs a propensity score‐matching approach to examine the direct effects of adoption of Bacillus thuringiensis (Bt) cotton on yields, pesticide demand, household income and poverty, using cross‐sectional data from a survey of farmers in the Punjab province of Pakistan. Generally, the findings reveal that adoption of the new technology exerts a positive and significant impact on cotton yields, household income and poverty reduction, and a negative effect on the use of pesticides. The positive and significant impact of the technology on yields and household income is consistent with the potential role of new agricultural technology in directly reducing rural poverty through increased farm household income.     

人力资本对贫困地区农村家庭产出的贡献——基于黑龙江省的实证分析

[目的]"打赢脱贫攻坚战,是今明两年必须完成的硬任务",剩余贫困人口的脱贫和已脱贫人口的发展亟需释放贫困地区人力资本的力量。人力资本在脱贫阶段演进过程中起到不同的作用,是提高贫困地区农村家庭产出和实现脱贫的核心与关键。[方法]文章通过实地调研验证人力资本对脱贫的作用机理,并为实证分析提供数据支持,依据人力资本与贫困地区农村家庭产出的均衡方程,建立回归模型,结合人力资本在生产函数中的意义及规模报酬不变的条件约束,判断人力资本贡献率对农村家庭产出优化的影响。[结果]实地调研表明脱贫意愿对人力资本构成影响较大;回归分析表明人力资本对贫困家庭产出贡献大于资金资本,也大于知识技术资本;优化规划表明人力资本的积累有助于实现贫困地区农村家庭产出规模优化。[结论]应从健康状况、脱贫能力和脱贫意愿等方面加强人力资本积累,通过共享平台支撑促进人力资本与其他资本有机融合,以人力资本为核心构建内生脱贫模式。     

Understanding the adoption of climate change adaptation strategies among smallholder farmers: Evidence from land reform beneficiaries in South Africa

Climatic change has a negative impact on people’s livelihoods, agriculture, freshwater supply and other natural resources that are important for human survival. Therefore, understanding how rural smallholder farmers perceive climate change, climate variability, and factors that influence their choices would facilitate a better understanding of how these farmers adapt to the negative impacts of climate change. A Zero-inflated double hurdle model was employed to estimate the factors influencing farmers’ adoption of adaptation strategies and intensity of adoption at the household level in South Africa. Different socioeconomic factors such as gender, age, and experience in crop farming, institutional factors like access to extension services, and access to climate change information significantly influenced the adoption of climate change adaptation strategies among beneficiaries of land reform in South Africa. Concerning intensity of adoption, age, educational level, farming experience, on-farm training, off-farm income, access to information through ICT and locational variables are the significant determinants of intensity of adaptation strategies. Thus, education attainment, non-farm employment, farming experience are significant incentives to enhance smallholder farmers' adaptive capacity through the adoption of many adaptation approaches. This study therefore concluded that farm-level policy efforts that aim to improve rural development should focus on farmers’ education, on-farm demonstration and non-farm employment opportunities that seek to engage the farmers, particularly during the off-cropping season. The income from non-farm employment can be plough-back into farm operations such as the adoption of soil and water conservation, use of improved planting varieties, insurance, among others to mitigate climate variability and subsequently increase productivity. Policies and investment strategies of the government should be geared towards supporting education, providing on-farm demonstration trainings, and disseminating information about climate change adaptation strategies, particularly for smallholder farmers in the country. Thus, the government, stakeholders, and donor agencies must provide capacity-building innovations around the agricultural extension system and education on climate change using information and communication technologies.     

Projecting future crop productivity for global economic modeling

Assessments of climate change impacts on agricultural markets and land‐use patterns rely on quantification of climate change impacts on the spatial patterns of land productivity. We supply a set of climate impact scenarios on agricultural land productivity derived from two climate models and two biophysical crop growth models to account for some of the uncertainty inherent in climate and impact models. Aggregation in space and time leads to information losses that can determine climate change impacts on agricultural markets and land‐use patterns because often aggregation is across steep gradients from low to high impacts or from increases to decreases. The four climate change impact scenarios supplied here were designed to represent the most significant impacts (high emission scenario only, assumed ineffectiveness of carbon dioxide fertilization on agricultural yields, no adjustments in management) but are consistent with the assumption that changes in agricultural practices are covered in the economic models. Globally, production of individual crops decrease by 10–38% under these climate change scenarios, with large uncertainties in spatial patterns that are determined by both the uncertainty in climate projections and the choice of impact model. This uncertainty in climate impact on crop productivity needs to be considered by economic assessments of climate change.     

Agro-pastoralism under climate change: Institutions and local climate adaptations in northern China

The livelihoods of resource-dependent peoples are vulnerable to climate variability. This study focuses on how local climate adaptations, which have been sustained through long-term interactions with local ecologies, have changed in the face of the challenges caused by climate change and policy interventions. Case studies were conducted in two agro-pastoral counties of northern China, a region that confronts frequent drought and that has experienced extensive institutional changes over recent decades. Based on the exploration of four adaptation strategies, the field results show that both counties have experienced an acceleration of livelihood diversification, an increase in storage and market exchanges, and a dramatic reduction in previously common pooling. The findings reveal that these adaptations are not a direct result of coping with climate risks but rather are indicative of livelihood strategies that result from the combined impacts of institutional, socioeconomic and climatic changes. Current institutional arrangements have negative impacts on local climate adaptations. This is particularly true for those with limited livelihood options, and such arrangements may therefore foster an increase in inequality with regard to household adaptive capacities over the long term. Therefore, this study recommends flexible policies that facilitate local arrangements rather than the current one-for-all policy.     

全球气候变化对海岛旅游地的影响与启示

气候既是海岛旅游业发展的自然条件,又是主要的资源,全球气候的异常变化影响海岛旅游资源的数量与质量、客流的空间与季节移动,并导致传统海岛旅游目的地的萎缩。全球气候变化对我国海岛旅游业的影响日益显著,必须及时调整海岛旅游发展的对策：大力发展生态旅游、可持续旅游;探究旅游者对气候变化的适应;改善海岛旅游目的地服务设施;重新进行海岛旅游规划;重视旅游主体人群的教育,以适应全球气候变化带来的巨大影响。     

Farming systems and Conservation Agriculture: Technology,structures and agency in Malawi

Conservation Agriculture (CA) is advocated as an agricultural innovation that will improve smallholder famer resilience to future climate change. Under the conditions presented by the El Niño event of 2015/16, the implementation of CA was examined in southern Malawi at household, district and national institutional levels. Agricultural system constraints experienced by farming households are identified, and in response the technologies, structures and agency associated with CA are evaluated. The most significant constraints were linked to household health, with associated labour and monetary impacts, in addition to the availability of external inputs of fertiliser and improved seed varieties. Our findings show that such constraints are not adequately addressed through current agricultural system support structures, with the institutions surrounding CA (in both Government extension services and NGO agricultural projects) focusing attention predominantly at field level practice, rather than on broader system constraints such as education and health support systems. Limited capacity within local institutions undermines long term efforts to implement new technologies such as CA. It is vitally important that the flexibility of farmers to adapt new technologies in a locally-appropriate manner is not closed down through national and institutional aims to build consensus around narrow technical definitions of a climate-smart technology such as CA. To enable farmers to fully utilise CA programmes, interventions must take a more holistic, cross-sectoral approach, understanding and adapting to address locally experienced constraints. Building capacity within households to adopt new agricultural practices is critical, and integrating healthcare support into agricultural policy is a vital step towards increasing smallholder resilience to future climate change.     

农户IPM技术采纳行为影响因素分析——基于安徽省芜湖市的实证

本文基于安徽省芜湖市以本地就业为主的386户稻农调研数据,采用Logit模型分析了农户IPM技术采纳行为的影响因素。研究表明,农民田间学校能够显著促进农户IPM技术采纳程度;户主非农兼业对化学防治型、生物防治型IPM技术采纳有显著正向影响,但对物理防治型IPM技术采纳影响不显著;耕地规模越大的农户越偏好物理防治型IPM技术,也越厌恶生物防治型IPM技术;农户耕地块数越多化学防治型、生物防治型IPM技术的采纳程度越低;但农民的健康意识、环境保护意识对农户IPM技术采纳影响不显著。     

Adapting the optimal selective-logging of Scots pine (Pinus sylvestris L.) stands in NE Spain to increasing CO2 concentrations

Predicted increases in CO₂ concentrations will affect forest ecosystems. In particular, they will impact tree growth, which in turn affects reproduction and mortality and consequently, forest planning. This study integrates different climate change scenarios of future biogeochemical processes and an economic model into a forest management model to determine the optimal selective-logging regime of Scots pine stands. It analyzes the economic implications of the management changes in comparison with the business as usual strategy. Adaption to new climatic conditions shows that it is optimal to increase the number of standing trees and to reduce the age of the logged trees. The results suggest that the failure to adapt the management regime has clear implications on the profitability of forests. Moreover, they show that higher mortality is likely to have a significant impact on the optimal forest management regime.     

Climate change and Australia's comparative advantage in broadacre agriculture1

Australia has long been a major exporter of the products of broadacre agriculture, a production system well suited to the economic and climatic conditions of the country. Presumably, it holds a comparative advantage in these products, among which grain crops and grazing livestock predominate. However, the future plausibility of this proposition is sensitive to the projected impacts of climate change. This article develops a framework to quantify the future patterns of comparative advantage in broadacre agriculture, given the projections of several global climate models. We find empirical support for the conventional wisdom, and note substantial resilience and robustness in Australia's comparative advantage under a number of scenarios.     

Adaptation in agriculture: historic effects of heat waves and droughts on UK agriculture

Extreme weather events are expected to increase in frequency and/or severity under climate change. Recent examples of these types of events, such as the heat wave in Europe in 2003, have caused considerable damage to crops and agriculture and substantial economic damage. If similar damage was incurred every time such an event occurred in the future, it would cause increasingly serious loss to social welfare and the economy as the frequency or intensity of these events increased. However, agriculture has a history of adapting to shocks, and in this paper we aim to determine whether there has been a systematic reduction in damage from historic extreme events over time in the agricultural sector in the UK. The impact of comparable droughts or heat waves over the past four decades is compared, and for many commodities there appears to have been a reduction in damage over time, to the point where recent events have had a minimal impact on production, indicating that the sector is relatively well adapted to the current climate. We discuss whether this type of adaptation can be sustained into the future under more rapid rates of change, or whether the ‘low-hanging’ fruits of adaptation have been picked.     

Evidence of climate change impacts on crop comparative advantage and land use

Relative agricultural productivity shocks emerging from climate change will alter regional cropland use. Land allocations are sensitive to crop profits that in turn depend on yield effects induced by changes in climate and technology. We develop and apply an integrated framework to assess the impact of climate change on agricultural productivity and land use for the U.S. Northern Great Plains. Crop-specific yield–weather models reveal crop comparative advantage due to differential yield impacts of weather across the region's major crops, that is, alfalfa, wheat, soybeans, and maize. We define crop profits as a function of the weather-driven yields, which are then used to model land use allocation decisions. This ultimately allows us to simulate the impact of climate change under the RCP4.5 emissions scenario on land allocated to the region's major crops as well as to grass/pasture. Upon removing the trends effects in yields, climate change is projected to lower yields by 33–64% over 2031–2055 relative to 1981–2005, with soybean being the least and alfalfa the most affected crops. Yield projections applied to the land use model at present-day input costs and output prices reveals that Dakotas’ grass acreage will increase by up to 23%, displacing croplands. Wheat acreage is expected to increase by up to 54% in select southeastern counties of North Dakota and South Dakota, where maize/soy acreage had increased by up to 58% during 1995–2016.     

气候变化对农户生计的影响研究综述

气候变化是21世纪人类面临的最严峻挑战之一,加剧了许多国家和地区的脆弱性,对以自然资源为生计基础的农业人口的影响尤为显著,明确气候变化对农户生计的影响,对于制定有效的气候变化适应政策,增强农户的气候变化适应能力,减轻农村贫困人口生计脆弱性具有重要意义。目前,国内外围绕气候变化对农户生计影响开展了许多研究,主要集中在过去或当前气候变化对水资源、土地、农作物、病虫害、人类健康等农户生计资本的宏观影响以及局地或区域尺度上气候变化对农户生计策略选择的影响等方面。从发展趋势看,亟需开展气候变化对农户生计的影响机理及适应机制研究,建立合理的气候变化对农户生计影响的评估框架,加强对模拟、分析和预测气候变化及其与其他压力相结合对农户生计要素的可能影响进行广泛评估,科学把握农户生计对气候变化脆弱性的关键影响因素,这对人类科学地适应气候变化和促进人类福祉和恢复力的提升具有重大的科学价值和现实意义。     

Adaptation and Climate Change Impacts: A Structural Ricardian Analysis of Farm Types in Germany

Based on farm census data, we explore the climate‐dependent incidence of six farm types and the climate‐induced impacts on land rental prices in Germany. We apply a structural Ricardian approach by modeling the dominant farm type at 9,684 communities as depending on temperature, precipitation and other geographic variables. Rents per farm type are then modeled as depending on climate and other conditioning variables. These results allow the projection of the consequences of climate change as changes in our climate variables. Our results indicate that permanent‐crop farms are more likely to dominate in higher temperatures, whereas forage or mixed farms dominate in areas of higher precipitation levels. Land rental prices display a concave response to increases in annual precipitation, and appear to increase linearly with rising annual temperature. Moderate‐warming simulation results for future decades benefit most farm types but seem to penalise forage farms. Rental prices are projected to increase, ceteris paribus, for all farm types.     

劳动力转移下不同生计农户低碳用能影响因素以浙豫陕3省农户为例

目的 农户用能的低碳转型对推进我国能源消费革命、缓解能源贫困和减少环境污染具有重要意义。方法 文章利用“劳动力转移与农村生活能源”2018年专项调查数据并采用多元线性及Logit回归模型考察劳动力转移下不同生计农户低碳用能影响因素。结果 劳动力转移程度及性别对一兼户低碳用能有显著负向影响，而劳动力转移空间对其有显著正向影响；劳动力转移程度及空间对二兼户低碳用能有显著正向影响，而劳动力转移性别对其有显著负向影响；劳动力转移程度、空间及性别对非农户低碳用能均有显著正向影响；户主受教育水平对4类农户高质商品用能有显著正向影响，而能源价格对其有显著负向影响；户主年龄、耕地面积对4类农户新型可再生能源选择有显著负向影响。结论 在乡村振兴战略进程中劳动力转移能够促进农户生活用能向可持续低碳转型，户主受教育水平、户主年龄、能源价格及耕地面积的影响不容忽视；科学引导劳动力转移及低碳用能亟待加强。     

Did the 2008–2009 Food and Financial Crises Affect Child Mortality? The Case of Sub-Saharan Africa

We estimate an aggregate model of child mortality on a panel of 40 African countries over the period 1995–2007. This model is then used to assess the impact of the 2008–2009 food and financial crises on child mortality, by comparing the number of child deaths computed under a “business-as-usual scenario” with those computed under the actual 2008–2009 “crisis scenario”. According to the simulation results, the 2008–2009 food price rise and recession caused a statistically non-significant additional 27,000 child deaths. However, if the 2008–2009 changes in other determinants of child mortality are factored in, the number of child deaths declined by 15,000. This unexpected result is explained by the fact that the effects of the rise in domestic food prices and the recession were offset in most of the region by the protective effect on the under-five mortality rate of a surge in food production, and by a rise in public expenditure on and foreign aid to the health sector.     

农户行为层面生态环境问题研究进展与述评

采用文献回顾法和归纳法,从研究内容、研究视角、研究区域、研究方法和手段、数据获取等方面对农户层面生态环境问题的相关研究进行梳理与分析,最后总结了现有研究存在的问题,并探讨了未来农户层面生态环境问题研究发展的方向。主要结论如下:(1)研究内容涉及农户行为引起的农业环境问题类型、农户行为的生态环境效应、农户环境保护行为与生态建设行为、农业环境保护政策创新等方面;(2)研究视角主要包括以农业生产行为决策者农户为中心内生视角和以农户需求与以农户行为为出发点的外部视角,研究区域主要集中在经济发达地区;(3)在研究方法方面,早期主要是采用一般描述、定性分析和"事前"估计法,近年来"事后"计量模型的研究逐步增多,趋于多样化和综合性;(4)数据获取主要是农户问卷调查和参与式农村评估方法;(5)今后研究应加强农户行为对环境影响的定量评价与跟踪研究、农户环境保护响应决策机制、基于农户行为的环境政策设计等方面的研究,在数据获取方面,应将地理空间信息与问卷调查、社会经济状况结合起来,并进行农户行为与生态环境变化的长期跟踪。     

Does Conservation Agriculture Change Labour Requirements? Evidence of Sustainable Intensification in Sub-Saharan Africa

Population growth, increasing wealth and changing diets require agriculture in Sub-Saharan Africa to intensify to meet future food demand and ensure food security in the region. Conservation agriculture can increase yields in the long run and reduce the negative environmental impacts of intensive farming. In changing the mix of resources used and how they are managed, the adoption of conservation agriculture can have a direct impact on farm labour. We study the relationship between conservation agriculture and labour input requirements as observed in five Sub-Saharan African countries. We focus on the amount of work required and the source of the work employed (household or hired, by gender, by children and by production stage). We apply multinomial endogenous switching regression models on a panel of household and farm data from Ethiopia, Kenya, Malawi, Mozambique and Tanzania. We find that conservation agriculture increases farms’ labour input requirements. Higher demand is driven by more work during the harvesting and threshing stages. Increases in labour requirements are usually met by household labour, not paid work. The workload change is also higher for women than for men, and, in certain cases, is met by children.