ArticlePDF Available

We Already Grow Enough Food for 10 Billion People … and Still Can't End Hunger

  • Institute for Food and Development Policy
This article was downloaded by: [Mr Eric Holt-Gimenez]
On: 01 August 2012, At: 11:02
Publisher: Taylor & Francis
Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered
office: Mortimer House, 37-41 Mortimer Street, London W1T 3JH, UK
Journal of Sustainable Agriculture
Publication details, including instructions for authors and
subscription information:
We Already Grow Enough Food for 10
Billion People … and Still Can't End
Eric Holt-Giménez
, Annie Shattuck
, Miguel Altieri
, Hans
& Steve Gliessman
Food First, Oakland, CA
University of California, Berkeley, CA
Millennium Institute, Washington, DC
University of California, Santa Cruz, CA
Version of record first published: 24 Jul 2012
To cite this article: Eric Holt-Giménez, Annie Shattuck, Miguel Altieri, Hans Herren & Steve Gliessman
(2012): We Already Grow Enough Food for 10 Billion People … and Still Can't End Hunger, Journal of
Sustainable Agriculture, 36:6, 595-598
To link to this article:
Full terms and conditions of use:
This article may be used for research, teaching, and private study purposes. Any
substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing,
systematic supply, or distribution in any form to anyone is expressly forbidden.
The publisher does not give any warranty express or implied or make any representation
that the contents will be complete or accurate or up to date. The accuracy of any
instructions, formulae, and drug doses should be independently verified with primary
sources. The publisher shall not be liable for any loss, actions, claims, proceedings,
demand, or costs or damages whatsoever or howsoever caused arising directly or
indirectly in connection with or arising out of the use of this material.
Journal of Sustainable Agriculture, 36:595–598, 2012
Copyright © Taylor & Francis Group, LLC
ISSN: 1044-0046 print/1540-7578 online
DOI: 10.1080/10440046.2012.695331
We Already Grow Enough Food for 10 Billion
People ... and Still Can’t End Hunger
A new a study from McGill University and the University of Minnesota pub-
lished in the journal Nature compared organic and conventional yields from
66 studies and 316 trials (Seufert et al. 2012). Researchers found that organic
systems on average yielded 25% less than conventional, chemical-intensive
systems—although this was highly variable and context specific. Embracing
the current conventional wisdom, authors argue for a combination of con-
ventional and organic farming to meet “the twin challenge of feeding a
growing population, with rising demand for meat and high-calorie diets,
while simultaneously minimizing its global environmental impacts” (Seufert
et al. 2012, 3).
Unfortunately, neither the study nor the conventional wisdom addresses
the real cause of hunger.
Hunger is caused by poverty and inequality, not scarcity. For the past
two decades, the rate of global food production has increased faster than
the rate of global population growth. According to the Food and Agriculture
Organization of the United Nations (2009a, 2009b) the world produces
more than 1
times enough food to feed everyone on the planet. That’s
already enough to feed 10 billion people, the world’s 2050 projected pop-
ulation peak. But the people making less than $2 a day—most of whom
are resource-poor farmers cultivating un-viably small plots of land—cannot
afford to buy this food.
In reality, the bulk of industrially produced grain crops (most yield
reduction in the study was found in grains) goes to biofuels and confined
animal feedlots rather than food for the one billion hungry. The call to
double food production by 2050 only applies if we continue to prioritize the
growing population of livestock and automobiles over hungry people.
Actually, what this new study does tell us is how much smaller the yield
gap is between organic and conventional farming than what critics of organic
agriculture have assumed. Smil’s (2001) claim that organic farming requires
twice the land base has become a conventional mantra. In fact, when we
unpack the data from the Nature study, we find that for many crops and
in many instances, the reported yield gap is minimal. With new advances
in seed breeding for organic systems, and with the transition of commercial
Downloaded by [Mr Eric Holt-Gimenez] at 11:02 01 August 2012
596 E. Holt-Giménez et al.
organic farms to diversified farming systems that have long been shown to
“over-yield” in comparison to monocultures, this yield gap will close even
further (see Vandermeer 1989).
The longest running side-by-side study comparing conventional chemi-
cal agriculture with organic methods (over 30 years) found organic yields
match conventional in good years and outperform them under drought
conditions and environmental distress (Rodale Institute 2012)—a critical
property as climate change increasingly serves up extreme weather condi-
tions. A major study carried out in Africa by the United Nations Development
Program concluded that organic methods lowered costs and provided more
economic benefits to farming communities than conventional agriculture
(Pretty et al. 2008). Moreover, farming like a diversified ecosystem renders
a higher resistance to extreme climate events, which translates into lower
vulnerability and higher long-term farm sustainability (Holt-Giménez 2002;
Philipott et al. 2009; Rosset et al. 2011).
The Nature article examined yields in terms of tons per acre and did
not address efficiency (i.e., yields per units of water or energy) nor environ-
mental externalities (i.e., the environmental costs of production in terms of
greenhouse gas emissions, soil erosion, biodiversity loss, etc.) and fails to
mention that conventional agricultural research enjoyed 60 years of massive
private and public sector support for crop genetic improvement, dwar fing
funding for organic agriculture by 99 to 1.
The higher performance of conventional over organic methods may
hold between what are essentially both mono-cultural commodity farms.
This misleading comparison sets organic agriculture as a straw man to be
knocked down by its conventional counterpart. But for the 1.5 billion sub-
sistence farmers working small plots—producing around half the world’s
food—monocultures of any kind are unsustainable. Noncommercial poly-
cultures are better for balancing diets, reducing risk, and thrive without
agrochemicals. Agroecological methods that emphasize rich crop diversity
in time and space conserve soils and water and have proven to produce
the most rapid, recognizable and sustainable results among poor farm-
ers (Altieri 2002). In areas in which soils have already been degraded by
conventional agriculture’s chemical “packages,” agroecological methods can
increase productivity by 100–300% (Bunch 1985; Natarajan and Willey 1996;
Holt-Giménez 2006).
This is why the U.N. Special Rapporteur on the Right to Food released
a report advocating for structural reforms and a shift to agroecology (De
Schutter 2010). It is why the 400 experts commissioned for the four-
year International Assessment on Agriculture, Science and Knowledge for
Development (IAASTD 2008) also concluded that agroecology and locally
based food economies (rather than the global market) where the best
strategies for combating poverty and hunger.
Downloaded by [Mr Eric Holt-Gimenez] at 11:02 01 August 2012
Editorial 597
Raising productivity for resource-poor farmers is one piece of ending
hunger, but how this is done—and whether these farmers can gain access to
more land—will make a big difference in combating poverty and ensuring
sustainable livelihoods. The conventional methods already employed for
decades by poor farmers have a poor track record in this regard.
Can conventional agriculture provide the yields we need to feed 10 bil-
lion people by 2050? Given climate change, the answer is an unsustainable
maybe. The more important question is, at what social and environmental
cost? To end hunger we must end poverty and inequality. For this chal-
lenge, agroecological approaches and structural reforms that ensure that
resource-poor farmers have the land and resources they need for sustainable
livelihoods are the best way forward.
Eric Holt-Giménez, Food First, Oakland, CA
Annie Shattuck, University of California, Berkeley, CA
Miguel Altieri, University of California, Berkeley, CA
Hans Herren, Millennium Institute, Washington, DC
Steve Gliessman, University of California, Santa Cruz, CA; JSA, Editor
Altieri, M. A. 2002 Agroecology: the science for natural resource management for
poor farmers living in marginal environments. Agriculture, Ecosystems and
Environment 93: 1–24.
Bunch, R. 1985. Two ears of cor n: A Guide to people-centered agricultural
improvement. Oklahoma City, OK: World Neighbors.
De Schutter, O. 2010. Agroecology and the right to food. United Nations Office of
the Special Rapporteur on the Right to Food. A/HRC/16/49. http://www.srfood.
pdf (accessed March 24, 2012).
Food and Agriculture Organization of the United Nations. 2009a. 1.02 billion
hungry. Available from:
(accessed 28 June 2010).
Food and Agriculture Organization of the United Nations. 2009b. The state of
food insecurity in the world. Rome, Italy: Economic and Social Development
Department Food and Agriculture Organization of the United Nations.
Holt-Giménez, E. 2002. Measuring farmers’ agroecological resistance after Hurricane
Mitch in Nicaragua: a case study in participatory, sustainable land management
impact monitoring. Agriculture, Ecosystems & Environment 93: 87–105.
Holt-Giménez, E. 2006. Campesino a Campesino: Voices from Latin America’s farmer
to farmermovement for sustainable agriculture. Oakland, CA: Food First Books.
International Assessment of Agricultural Knowledge, Science and Technology
for Development. 2008. IAASTD reports.
2713 (accessed 16 October 2008).
Downloaded by [Mr Eric Holt-Gimenez] at 11:02 01 August 2012
598 E. Holt-Giménez et al.
Natarajan, M., and R. W. Willey. 1996. The effects of water stress on yields
advantages of intercropping systems. Field Crops Research 13: 117–131.
Philpott, S. M., B. B. Lin, S. Jha, and S. J. Brines. 2009 A multiscale assessment of hur-
ricane impacts on agricultural landscapes based on land use and topographic
features. Agriculture, Ecosystems and Environment, 128(1–2), 12–20.
Pretty, J., R. Hine, and S. Twarog. 2008. Organic agriculture and food security
in Africa. UNEP-UNCTAD Capacity-Building Task Force on Trade. New York
and Geneva: United Nations Conference on Trade and Development/United
Nations Environment Programme.
Rodale Institute. 2012. The farming systems trial: celebrating 30 years.Emmaus,PA:
Rodale Press.
Rosset, P. M., B. Machín-Sosa, A. M. Roque-Jaime, and D. R. Avila-Lozano. 2011. The
Campesino-to-Campesino agroecology movement of ANAP in Cuba. Journal of
Peasant Studies 38: 161–191.
Seufert, V., N. Ramankutty, and J. A. Foley. 2012. Comparing the yields of organic
and conventional Agriculture. Nature DOI:10.1038/nature11069
Smil, V. 2001. Enriching the earth: Fritz Haber, Carl Bosch and the transformation
of world food production. Cambridge, MA: The MIT Press.
Vandermeer, J. 1989. The ecology of intercr opping. Cambridge, UK: Cambridge
University Press.
Downloaded by [Mr Eric Holt-Gimenez] at 11:02 01 August 2012
... The higher food demand due to increasing human population (UN-WWAP, 2015), as well as poverty and unequal distribution of resources (Holt-Giménez et al., 2012) highlights the necessity for more efficient and sustainable agricultural practices. Wastewater reuse for irrigation can relieve environmental and economic pressures of agriculture and increase ...
... year-round water accessibility (Holt-Giménez et al., 2012;Jovanovic, 2008;Jaramillo and Restrepo, 2017;Jimenez-Cisneros, 2006). Considered widespread practice, 65% of irrigated croplands are located in wastewaterdependent catchments, of which 82% are located in countries where <75% of wastewater is treated (Thebo et al., 2017). ...
... A limitation of the model is that it was not possible to include all the variables known to affect sorption and important sorption mechanisms, such as cation exchange, Table 1]. R 2 X (UN-WWAP, 2015) refers to the proportion of variability explained by principal component 1 (t (UN-WWAP, 2015)) and R 2 X (Holt-Giménez et al., 2012) refers to the proportion of variability explained by the second principal component. cation bridging on clay surfaces, surface complexation, and hydrogen bonding (Tolls, 2001) are not accounted for in the model. ...
Full-text available
The first meta-analysis and modelling from batch-sorption literature studies of the soil/water partitioning of pharmaceuticals is presented. Analysis of the experimental conditions reported in the literature demonstrated that though batch-sorption studies have value, they are limited in evaluating partitioning under environmentally-relevant conditions. Recommendations are made to utilise environmental relevant pharmaceutical concentrations, perform batch-sorption studies at temperatures other than 4, 20 and 25 °C to better reflect climate diversity, and utilise the Guideline 106 methodology as a benchmark to enable comparison between future studies (and support modelling and prediction). The meta-dataset comprised 82 data points, which were modelled using multivariate analysis; where Kd (soil/water partitioning coefficient) was the independent variable. The dependent variables fit into three categories: 1) pharmaceutical studied (including physical-chemical properties), 2) soil characteristics and 3) experimental conditions. The pharmaceutical solubility, the soil/liquid equilibration time (prior to adding the pharmaceutical), the soil organic carbon, the soil sterilisation method and the liquid phase were found to be significantly important variables for predicting Kd.
... We currently produce enough food to feed 10 billion people; about 30% more than the global population. As Holt-Giménez et al. (2012) point out, hunger is caused by poverty and inequality, not food scarcity, at a global scale. Those that live on less than US$2 a day, mainly subsistence farming families, cannot afford to buy sufficient food. ...
... If the priority is better health for all, global food systems must stop fuelling diets with adverse public health impacts, requiring a systemic change to global food production systems (Global Panel on Agriculture and Food Systems for Nutrition, 2020). A significant proportion of industriallyproduced grain crops goes to biofuels and confined animal feedlots rather than food for the 1 billion hungry (Holt-Giménez et al., 2012). Therefore, calls to double food production by 2050 only apply if we continue to prioritise the growing population of livestock and automobiles over hungry people. ...
Technical Report
Full-text available
Managing phosphorus underpins the sustainability of the food system and is vital in achieving future food security. Strategies to deliver phosphorus sustainability include a transition to circular phosphorus value chains, land-use planning approaches that support greater phosphorus use efficiency and a reduction in consumption of animal products. Affordable access to sustainable phosphorus sources is imperative to ensure food provision for all and to protect the livelihoods of smallholder and marginal farmers.
... Transformation of food systems around the globe is urgent, not only because of their GHG emissions but also because they fall completely short in equitably distributing food and providing food and nutrition security (19), resulting in hunger, malnutrition, and overconsumption (20). In addition, their wider environmental footprint related to biodiversity loss, deforestation, soil degradation, and water pollution is a key driver of environmental degradation (21). ...
Without rapid changes to agriculture and food systems, the goals of the 2015 Paris Agreement on climate change will not be met. Food systems are one of the most important contributors to greenhouse gas (GHG) emissions, but they also need to be adapted to cope with climate change impacts. Although many options exist to reduce GHG emissions in the food system, efforts to develop implementable transformation pathways are hampered by a combination of structural challenges such as fragmented decision-making, vested interests, and power imbalances in the climate policy and food communities, all of which are compounded by a lack of joint vision. New processes and governance arrangements are urgently needed for dealing with potential trade-offs among mitigation options and their food security implications.
... Overall, the food produced could feed about 10 billion people globally. However, the food system fails to achieve a fair allocation of resources [1]. Nearly 1.3 billion tons of food (about one-third of total production) are wasted every year, and approximately 56% of waste occurs in industrialised countries. ...
Full-text available
Although the different alternative food networks (AFNs) have experienced increases worldwide for the last thirty years, they are still unable to provide an alternative capable of spreading on a large scale. They in fact remain niche experiments due to some limitations on their structure and governance. Thus, this study proposes and applies a design method to build a new sustainable food supply chain model capable of realizing a “jumping scale”. Based on the theoretical and value framework of the Civil Economy (CE), the Economy for the Common Good (ECG), and the Development on a Human Scale (H-SD), the proposed design model aims to satisfy the needs of all stakeholders in the supply chain. Max-Neef’s Needs Matrix and Design Thinking (DT) tools were used to develop the design model. Applying the design method to the food chain has allowed us to develop the concept of the “Food Village”, an innovative food supply network far from the current economic mechanisms and based on the community and eco-sustainability.
... Wheat represents 13.91% of the total cereal planted area and 81% of the total food output volume (CSA, 2020). Our world produces food for over 10 billion people; however, 815 million still suffer from hunger or malnutrition (FAO, IFAD, UNICEF, WFP, WHO, 2017;Holt-Giménez et al., 2012). Likewise, Ethiopia produces the most wheat in SSA, although it is still a net importer (Hodson et al., 2020). ...
Full-text available
The blanket NP fertilizer recommendation over the past five decades in Ethiopia did not result in a significant increment of crop productivity. The main lack of success was highly linked to the extrapolating approach of one site success to others without considering the climate, soil, and ecological setting and variations. As a result, a new fertilization approach was desperately needed, and with this premise, new blended fertilizers are now being introduced to replace the conventional approach. Thus, the objective of this study was to examine the effect of NPSZnB blended fertilizer on bread wheat yield attributes, quality traits and use efficiency in two different soil types under rain-fed conditions in Ayiba, northern Ethiopia. Relevant agronomic data were evaluated and recorded from plots of each soil types for analysis. The analysis of variance revealed a significant (p < 0.001) variation on all the agronomic and grain quality traits due to the main and interaction effects of soil type and fertilizer treatment factors. Most agronomic and quality characteristics recorded the highest result in the highest treatment applications (175 and 150 kg NPSZnB ha −1) in both soils. Yield and grain quality traits of bread wheat was also found better under fertilized plots than unfertilized plots. In both soil types increasing application of the new blended fertilizer rate from 50-175 kg NPSZnB ha −1 showed an increasing trend in grain yield from 1.6 to 4.3 and 2.5 to 5.4 t ha −1 in Vertisol and Cambisol soils, respectively. The varied yield as a response of fertilizer treatments across soils signifies soil-specific fertilization approach is critically important for production increment. On the other hand, based on the partial budget analysis the highest net benefit with the highest marginal rate of return in both Vertisol and Cambisol soils were obtained when treated with 100 and 125 kg NPSZnB ha −1 , respectively. Therefore, to produce optimum bread wheat yield under rainfed conditions in Ayiba (northern Ethiopia) fertilizing Vertisols with 100 kg NPSZnB ha −1 and fertilizing Cambisols with 125 kg NPSZnB ha −1 is recommended.
... As northern Canada becomes a new "climate-driven agriculture frontier" (Hannah et al. 2020) we have considered two global agriculture frameworks. The first is a conventional agriculture paradigm that has developed within food regimes and settler colonialism, and has globally contributed to ecological destruction, Indigenous land dispossession, and corporate control (Grey and Patel 2015;Holt-Giménez et al. 2012;Patel 2012). The second framework is agroecology, which began in Indigenous and peasant fields of Latin America and has come to be identified with radical movements for land and food sovereignty around the world (Copeland 2019;Laforge et al. 2021). ...
Full-text available
Warming temperatures in the circumpolar north have led to new discussions around climate-driven frontiers for agriculture. In this paper, we situate northern food systems in Canada within the corporate food regime and settler colonialism, and contend that an expansion of the conventional, industrial agriculture paradigm into the Canadian North would have significant socio-cultural and ecological consequences. We propose agroecology as an alternative framework uniquely accordant with northern contexts. In particular, we suggest that there are elements of agroecology that are already being practiced in northern Indigenous communities as part of traditional hunter-gatherer food systems. We present a framework for agroecology in the North and discuss its components of environmental stewardship, economies, knowledge, social dimensions and governance using examples from the Dehcho region, Northwest Territories, Canada. Finally, we discuss several challenges and cautions in creating policy around agroecology in the North and encourage community-based research in developing and testing this framework moving forward.
... Therefore, to the three ecological principles aforementioned, here we add a social dimension: (The circularity principle of) Fairness and accessibility. Quantitatively speaking, in terms of proteins and volumes, right now, there is enough food to feed the world [52,53]. However, concerning food, accessibility and sovereignty are important economic and political issues at stake [54]. ...
Full-text available
The concept of circularity is currently proposed to address key sustainability issues affecting and affected by livestock production. Through a desk study, this paper evaluates some feed sources that are being developed in The Netherlands as an alternative to current feeds, namely food waste; seaweed; and localized production and alternative plant-based feed sources. These feed categories are evaluated according to four circularity criteria. The first two criteria concern standard circularity principles aimed at both stopping and preventing environmental damage as well as a focus on natural resources use efficiency: (1) Safeguard the health of ecosystems and (2) avoid the production of unnecessary products and use/recycle biomass effectively, as well as evaluating possible food–feed competition. In addition, two ‘people’ and ‘animal’ centred principles have been integrated: (3) fairness and accessibility and (4) animal health and wellbeing. The article concludes that people and animal centred principles are key to thinking of, developing, implementing, and evaluating circularity initiatives. Moreover, the article suggests that categories such as the local production of soya (approx. 132 ha) or seaweed (approx. 10–15 ha) are as yet irrelevant regarding production volumes within the Dutch context. However, some feed sources such as seaweed, insects, livestock leftovers produced at farms and abattoirs, and food waste might strengthen the transition towards more circular and sustainable practices.
Full-text available
The study examined the impact of environmental taxation on food security in sub-Saharan Africa. Panel data was obtained and ordinary least square regression was employed to analyze the data for the study. The findings of the study depicted environmental taxation having a negative effect with food security in sub-Saharan Africa. The recommendation which emanated from the findings is that proper carbon accounting and carbon pricing should be implemented to ensure that firms are taxed properly as well as tax justice should be promoted. This research throws light on the contribution of accountants as well as the accounting discipline to sustainable development issues such as climate change and food security.
Full-text available
This chapter approaches the relationships between mobility, hydrometeorological phenomena and health and makes a first exercise to try to understand how social inequalities intersect with natural phenomena due to global change, and impact the everyday lives of men and women in urban areas. It is argued that these intersections allow us to understand the socio environmental complexity in cities, as well as those social care practices that express a set of gender norms that prevent the exercise of women rights and allow the reproduction of power relations that maintain social and gender inequality gaps. The chapter proposes a methodological strategy that can allow us to understand how inequality processes, care and environmental degradation are interweave and articulated. Finally, it demonstrates the appropriateness of working together the concepts of habitability and care, in order to orient the climate agenda towards a framework that allow us to achieve socioenvironmental justice under a gender perspective.
Habitability has diverse meanings depending on the theoretical-conceptual framework and scale used. Here the term “regional habitability” is minted and its relation to a local watershed and global climate change are described. Furthermore, regional habitability is characterized for the Tijuana River Watershed using socio-economic and environmental indicators as well as Material and Energy Flow Analysis to describe the impacts related to the rapid urbanization in such watershed. Results indicated that this process demanded inputs of construction materials and electricity in two or three orders of magnitude; and make Tijuana depend on 90 % of water transferences from the Colorado River with a large energy investment and emission’s generation. The accelerated urbanization is associated to the regional development model as shown through a comparison with Monterrey. It is concluded that this development has not contributed to the urban environmental sustainability but to an environmental emergency; it has not increased urban resilience neither has improved its regional habitability.
Full-text available
Numerous reports have emphasized the need for major changes in the global food system: agriculture must meet the twin challenge of feeding a growing population, with rising demand for meat and high-calorie diets, while simultaneously minimizing its global environmental impacts. Organic farming—a system aimed at producing food with minimal harm to ecosystems, animals or humans—is often proposed as a solution. However, critics argue that organic agriculture may have lower yields and would therefore need more land to produce the same amount of food as conventional farms, resulting in more widespread deforestation and biodiversity loss, and thus undermining the environmental benefits of organic practices. Here we use a comprehensive meta-analysis to examine the relative yield performance of organic and conventional farming systems globally. Our analysis of available data shows that, overall, organic yields are typically lower than conventional yields. But these yield differences are highly contextual, depending on system and site characteristics, and range from 5% lower organic yields (rain-fed legumes and perennials on weak-acidic to weak-alkaline soils), 13% lower yields (when best organic practices are used), to 34% lower yields (when the conventional and organic systems are most comparable). Under certain conditions—that is, with good management practices, particular crop types and growing conditions—organic systems can thus nearly match conventional yields, whereas under others it at present cannot. To establish organic agriculture as an important tool in sustainable food production, the factors limiting organic yields need to be more fully understood, alongside assessments of the many social, environmental and economic benefits of organic farming systems.
Full-text available
Agricultural systems are increasingly vulnerable to the effects of extreme climate events. Yet strategies to reduce risk and vulnerability have not been greatly explored. Here, we examine the vulnerability of coffee agroforestry systems varying in management intensity (e.g. land use) and topographic features to disturbance related to Hurricane Stan in Chiapas, Mexico—a hurricane categorized by heavy rains and mild winds. An approximately 50 km2 area was chosen within a coffee-growing region where data were collected on a variety of topographic and landscape features (aspect, slope, elevation, distance to river) and vegetation characteristics (canopy cover, vegetation structure, tree density) as predictive factors of vegetation, economic, and landslide damage at three distinct spatial scales. At the plot level, we collected vegetation data later compiled into a vegetation complexity index. At the farm level, we collected data to understand the effect of the hurricane on economic damage and farm area affected by landslides. We also recorded number and volume of roadside landslides as a measure of post-hurricane disturbance. We then conducted a geo-spatial analysis to determine which factors contribute most to landslide occurrence at landscape scales. We found no effect of coffee management on vegetation damage or on economic losses at the plot or farm scale. At the farm scale, increasing management intensity (i.e. reduction in vegetation complexity) correlated with increased proportion of farm area affected by landslides (P = 0.014). Additionally, reduction in vegetation complexity was correlated with increased number (P = 0.0224) and volume (P = 0.062) of roadside landslides at the landscape level. Topographic and landscape features, such as distance to river (P = 0.004) and wind exposure/aspect (P = 0.044) strongly influenced landslide frequency at the landscape scale. Forest proximity and proportion of forest cover did not significantly influence the frequency or extent of landslide damage. We created hazard maps using the vegetation complexity index, distance to river, and wind exposure as the heaviest weighted factors to assess areas of the terrain with the greatest vulnerability. These maps present a practical result of this study, and offer a template in which land management policy can develop to lower regional vulnerability to landslide risk. These results show that farmers may be able to reduce vulnerability to extreme storm events by carefully managing their farms. Although farmers may not be able to control negative topographic features of their farms, increasing vegetation complexity within farms may be an efficient strategy to reduce some susceptibility to hurricane disturbance.
Full-text available
Agroecology has played a key role in helping Cuba survive the crisis caused by the collapse of the socialist bloc in Europe and the tightening of the US trade embargo. Cuban peasants have been able to boost food production without scarce and expensive imported agricultural chemicals by first substituting more ecological inputs for the no longer available imports, and then by making a transition to more agroecologically integrated and diverse farming systems. This was possible not so much because appropriate alternatives were made available, but rather because of the Campesino-a-Campesino (CAC) social process methodology that the National Association of Small Farmers (ANAP) used to build a grassroots agroecology movement. This paper was produced in a 'self-study' process spearheaded by ANAP and La Via Campesina, the international agrarian movement of which ANAP is a member. In it we document and analyze the history of the Campesino-to-Campesino Agroecology Movement (MACAC), and the significantly increased contribution of peasants to national food production in Cuba that was brought about, at least in part, due to this movement. Our key findings are (i) the spread of agroecology was rapid and successful largely due to the social process methodology and social movement dynamics, (ii) farming practices evolved over time and contributed to significantly increased relative and absolute production by the peasant sector, and (iii) those practices resulted in additional benefits including resilience to climate change.
The industrial synthesis of ammonia from nitrogen and hydrogen has been of greater fundamental importance to the modern world than the invention of the airplane, nuclear energy, space flight, or television. The expansion of the world's population from 1.6 billion people in 1900 to today's six billion would not have been possible without the synthesis of ammonia. In Enriching the Earth, Vaclav Smil begins with a discussion of nitrogen's unique status in the biosphere, its role in crop production, and traditional means of supplying the nutrient. He then looks at various attempts to expand natural nitrogen flows through mineral and synthetic fertilizers. The core of the book is a detailed narrative of the discovery of ammonia synthesis by Fritz Haber -- a discovery scientists had sought for over one hundred years -- and its commercialization by Carl Bosch and the chemical company BASF. Smil also examines the emergence of the large-scale nitrogen fertilizer industry and analyzes the extent of global dependence on the Haber-Bosch process and its biospheric consequences. Finally, it looks at the role of nitrogen in civilization and, in a sad coda, describes the lives of Fritz Haber and Carl Bosch after the discovery of ammonia synthesis.
Two experiments are reported in which a line-source irrigation system was used to study the effects of a range of moisture regimes (S1 to S5 in order of increasing stress due to insufficiency of moisture) on sole crops of sorghum, millet and groundnut, and intercrops of 1 row sorghum : 2 rows groundnut (SGG), 1 row sorghum : 3 rows groundnut (SGGG), 1 row millet : 1 row groundnut (MG), 1 row millet : 2 rows groundnut (MGG), 1 row millet : 3 rows groundnut (MGGG), and 1 row sorghum : 1 row millet (SM). The dry matter yield advantages of intercropping compared with sole cropping ranged from 8 to 30% for the millet/groundnut systems, 0 to 19% for the sorghum/groundnut systems and 5 to 15% for the sorghum/millet system; moisture stress had no consistent effect on these dry matter advantages. For reproductive yields, all the intercropping systems showed some increase in relative advantages with increase in stress because of higher harvest indices in intercropping than in sole cropping. Largest advantages were 93% for SGG at S5 moisture regime and 78% for MGG at S4 moisture regime, both of these being significantly greater than advantages at S1. The level of stress giving peak advantages depended on crop combination and crop proportions.It is emphasised that all intercropping treatments were of ‘replacement’ type in which the plant population of each crop was only a proportion of that of its sole crop and total population was equivalent to that in either of the sole crops. It is suggested that if total populations in the intercrops are higher than in the sole crops then, under stress conditions, intercropping yields could well be less than sole crop yields because of increased competition for moisture.
Throughout the developing world, resource-poor farmers (about 1.4 billion people) located in risk-prone, marginal environments, remain untouched by modern agricultural technology. A new approach to natural resource management must be developed so that new management systems can be tailored and adapted in a site-specific way to highly variable and diverse farm conditions typical of resource-poor farmers. Agroecology provides the scientific basis to address the production by a biodiverse agroecosystem able to sponsor its own functioning. The latest advances in agroecological research are reviewed in order to better define elements of a research agenda in natural resource management that is compatible with the needs and aspirations of peasants. Obviously, a relevant research agenda setting should involve the full participation of farmers with other institutions serving a facilitating role. The implementation of the agenda will also imply major institutional and policy changes.
A study using a participatory research approach and simple field techniques found significant differences in agroecological resistance between plots on “conventional” and “sustainable” farms in Nicaragua after Hurricane Mitch. On average, agroecological plots on sustainable farms had more topsoil, higher field moisture, more vegetation, less erosion and lower economic losses after the hurricane than control plots on conventional farms. The differences in favor of agroecological plots tended to increase with increasing levels of storm intensity, increasing slope and years under agroecological practices, though the patterns of resistance suggested complex interactions and thresholds. For some indicators agroecological resistance collapsed under extreme stress.
Contenido: 1) El nitrógeno en la agricultura; 2) Caminos tradicionales del nitrógeno; 3) Nuevos caminos de los nutrientes; 4) Un descubrimiento brillante; Creación de una industria; 6) Evolución de la síntesis del amoníaco; 7) Fertilizantes sintéticos; 8) Nuestra dependencia del nitrógeno; 9) Consecuencias de la dependencia; 10) Nitrógeno y civilización.