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opinion & comment
the FACE experiments, which typically
increase CO2 from ~370ppmto ~550ppm)
(Fig.1). Furthermore, S15’s synthesis of
FACE data is incomplete as it omits several
years of published data10,11, and incorrectly
estimates an overall eect size by taking
the median across experiments, species
and years, rather than calculating a more
appropriate response ratio12.
S15 concludes that CESM1-BGC, the
ESM most consistent with the satellite
NPP estimates, is an improvement over
other ESMs, likely due to its inclusion of
explicit carbon–nitrogen interactions. We
agree that the inclusion of such interactions
in ESMs is a desirable objective, and
that neglect of these in ‘carbon only’
ESMs risks overestimating long-term
CO2 eects on NPP2. However, it is
premature to reach this conclusion given
the inability of CESM1-BGC to capture
the magnitude of recent CO2 uptake13 or
even (uniquely among models tested) the
‘sign’ of the relationship between tropical
land temperatures and CO2 uptake14. In
addition, the land surface model (CLM4) in
CESM1-BGC underestimates the measured
NPP response to elevated CO2 from the
two longest-running FACE experiments—
predicting a smaller response than ten
other ecosystem models that included
nutrient limitations on NPP15.
In summary the comparison of satellite
and FACE estimates of CO2 fertilization
is invalid, and the discussion of nitrogen
limitations is based on a single model
that poorly represents the response of
1. Smith, W.K. etal. Nat. Clim. Change 6, 306–310 (2016).
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80, 1150–1156 (1999).
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J.Geophys. Res. 119, 794–807 (2014).
15. Zaehle, S. etal. New Phytol. 202, 803–822 (2014).
Martin G. De Kauwe1*, Trevor F. Keenan1,
Belinda E. Medlyn2, I. Colin Prentice1,3 and
Cesar Terrer3
1Macquarie University, Department of Biological
Sciences, North Ryde, New South Wales
2109, Australia. 2Hawkesbury Institute for
the Environment, Western Sydney University,
Locked Bag 1797, Penrith, New South Wales,
Australia. 3AXA Chair Programme in Biosphere
and Climate Impacts, Department of Life
Sciences, Imperial College London, Silwood Park
Campus, Buckhurst Road, Ascot SL5 7PY, UK.
Emissions from cattle farming in Brazil
To the Editor — de Oliveira Silva
and colleagues1 have proposed that, if
decoupled from deforestation, increasing
beef consumption may reduce greenhouse
gas emissions, while at the same time
suggesting that reducing consumption
may not signicantly alter greenhouse gas
emissions. However, the analysis contains
unrealistic assumptions and disregards a
series of other analyses corroborated by
historical data, aecting the robustness of
the conclusions. Sustainable intensication
is presented as a feasible socioecological
solution, despite the fact that this concept
is still a matter of controversy. At the most
general level, it lacks any solid empirically
based mechanism. More specically, it fails
to address equity and local governance
aspects that ought to be inherent in
Furthermore, the authors assume a
scenario in which deforestation can be
decoupled from changes in pasture area,
something that has not happened in the
historical record of the Brazilian Cerrado.
is assumption is based on the idea that
increases in yield eciency will result
in spare land returning to its natural
state3. Historically, however, agricultural
productivity increases have usually been
accompanied by farmland expansion4,5,
tomeet growing demand: this is oen
referred to as the Jevons paradox by
agricultural economists6. e authors
may have reasons to doubt the substantial
empirical evidence supporting this issue,
but they should acknowledge their rejection
of it in their underlying assumptions.
Similarly, their assumptions of prot
maximization and construction of a
production-optimization model are
problematic and arbitrary, considering the
voluminous existing literature showing
the importance of deviations from the
maximization motive7 and the need to
explicitly grapple with the assumptions
made in any optimization analysis.
e analysis does not take into
consideration the local dynamics of
small farming and indigenous resource
management. Livestock production by
traditional peoples and small farmers
is generally regarded as less harmful
to biodiversity and more sustainable
than intensive livestock on exotic grass
monocultures, although the outcomes are
very context specic8. e assumption that
the Cerrado may behave as a single large
prot-maximizing farm does not reect
the socioeconomic diversity of extant
landholders or the remarkable gamma
diversity of its various ecosystems.
Another questionable assumption
is the idea that pasture recovery can be
accomplished with fertilization in most
of the Cerrado, which is implausible even
before accounting for its negative eects on
soil, water, and greenhouse gas emissions.
e model also assumes a xed value for
emissions as a result of deforestation in
the Cerrado, neglecting the ecological
heterogeneity of the biome. e authors
propose recovery of degraded areas using
exotic grass, even though such exotic
species have potentially profound eects
on the functioning and biodiversity of
the Cerrado9. Furthermore, the model
ignores the regrowth of woody vegetation
when pasture is taken out of production.
us, it eectively assumes that secondary
succession back to forest, which results
in carbon sequestration in biomass and
carbon soil, can never occur10. ese
assumptions limit the practical utility of
this modelling exercise.
1. de Oliveira Silva, R. etal. Nat. Clim. Change 6, 493–497 (2016).
2. Loos, J. etal. Front. Ecol. Environ.12, 356–361 (2014).
3. Phalan, B. etal. Science 351, 450–451 (2016).
4. Rudel, T. K. etal. Proc. Natl Acad. Sci. USA 106, 20675–20680 (2009).
5. Perfecto, I. & Vandermeer, J. H. Proc. Natl Acad. Sci. USA
107, 5786–5791 (2010).
6. Polimeni, J. M. & Polimeni, R. I. Ecol. Complexity 3, 344–353 (2006).
7. Brown, C. etal. PLoS ONE 9, e114213 (2014).
opinion & comment
8. Giroldo, A. B. & Scariot, A. Biol. Conserv. 191, 150–158 (2015).
9. Pivello, V. R., Shida, C. N. & Meirelles, S. T. Biodivers. Conserv.
8, 1281–1294 (1999).
10. Poorter, L. etal. Nature 530, 211–214 (2016).
Fernando F. Goulart1*, Ivette Perfecto2,
JohnVandermeer3, Doug Boucher4,
M.JahiChappell5, Geraldo Wilson Fernandes6,
Aldicir Scariot7, Marcelo Corrêa da Silva8,
Washington Oliveira9, Rebecca Neville10,
JamesMoore11, Mercedes Bustamante9,
SoniaRibeiro Carvalho1 and
Britaldo Soares-Filho1
1Universidade Federal de Minas Gerais,
Análise e Modelagem de Sistemas
Ambientais/Centro de Sensoriamento
Remoto, Belo Horizonte, MG, CEP 31270-
900, Brazil. 2School of Natural Resources
and Environment, University of Michigan,
AnnArbor, Michigan 48109, USA.
3Department of Ecology and Evolutionary
Biology, University of Michigan, Ann Arbor,
Michigan 48109, USA. 4Union of Concerned
Scientists, 1825 K Street, NW, Washington
DC 20006, USA. 5Institute for Agriculture
and Trade Policy, Minneapolis, Minnesota
55404, USA. 6Universidade Federal de Minas
Gerais, Ecologia Evolutiva & Biodiversidade/
DBG, 30161-970 Belo Horizonte MG,
Brazil. 7Embrapa Genetic Resources and
Biotechnology, Brasília, DF 70770-917,
Brazil. 8Universidade Federal de Grande
Dourados, Faculdade de Ciências Agrária,
Itahum, Postal code 533, Brazil. 9Universidade
de Brasília, Programa de Pós-graduação
em Ecologia, Departamento de Ecologia,
Brasília, 70910-900, Brazil. 10Department of
Teaching and Learning, Washington State
University Vancouver, Vancouver, Washington
98686, USA. 11School of Biological Sciences,
Washington State University Vancouver,
Vancouver, Washington 98686, USA.
e-mail: goulart.
Reply to ‘Emissions from cattle farming in Brazil’
de Oliveira Silva et al. reply —
Goulertetal. make some interesting
observations about the context of our
study, its modelling assumptions and data.
We clarify these issues but refute that our
study is unrealistic or misleading. Indeed,
we have been conservative with some
assumptions and it would be possible and
plausible to accentuate the counterintuitive
result we present.
In our reference to sustainable
agricultural intensication (SAI) we note
the contested nature of the concept and do
not imply a comprehensive characterization
of the term. is includes the equity
and governance trade-os undoubtedly
encountered in more granular research
on mitigation. Our contribution provides
one mathematical example of a plausible
SAI scenario developed at a meaningful
scale. We hope it partly lls a conspicuous
gap in the literature, largely populated by
normative conceptual papers rather than
empirically based mechanisms’ that might
form policy evidence.
We suggest that the scenarios are based
on sound empirical evidence, referenced
in our supplementary information.
is includes the recently observed
decoupled livestock deforestation (DLD)
scenario that resulted from more rigorous
deforestation control and a changing
market environment1,2. e DLD contrasts
with the coupled livestock deforestation
scenarios, which encompass worst case
assumptions about how deforestation
responds to demand. We suggest these are
likely to accommodate potential Jevons
paradox eects.
e prot maximization assumption is
contestable, but we note that alternative
assumptions are no less subjective.
Furthermore, deviations from prot
maximization will not signicantly aect
the results or main conclusions. is is
because the level of intensication is not
based on prot maximization, as land
availability and demand are exogenous
to our model. In unreported analysis
other objective functions were tested (for
example, minimization of land use change)
with similar results.
While important, the heterogeneity
of local ecosystem dynamics and
gamma diversity are largely beyond the
resolution of the model we employed.
Nevertheless, we can draw some
conclusions in relation to the impacts of
intensication on biodiversity. We contest
the characterization of large intensive
farms versus smallholdings suggested by
Goulert and co-authors: recent monitoring
suggests the opposite3–5. Due to legal
enforcement, large ranchers are reducing
deforestation to avoid prosecution, while
signicant deforestation is attributable to
ere is considerable experimental
and practical evidence showing that
pasture recovery can be accomplished
with fertilization in much of the Cerrado6.
Moreover our scenarios account for all
related greenhouse gases using a life cycle
approach. Since little nitrogen is applied in
the Cerrado7, the issue of water pollution
is negligible. Water consumption for
intensication measures is also small,
demand being mostly for livestock. On
deforestation emissions, we suggest that
it is impossible to know in advance where
deforestation is going to happen in the
biome for the period of study. We are
condent that alternative assumptions on
which physiognomies would be converted
to grasslands would be at least as open to
being contested.
e study proposes recovery of degraded
areas already planted with exotic grasses.
We stated that recovery strategies are based
on existing Brachiaria spp. pastures as
the preferred species for pasture recovery,
productivity and costs (see supplementary
information). We also note evidence that
degraded pastures have worse eects
on ecosystem function than productive
pastures8. e use of native Cerrado
species for cattle production is of minor
Finally, there is no reason to believe that
land would be abandoned or taken out of
production within the demand range we
studied. Note that the scenarios were based
on projections to 2030. Even in the demand
scenario of 30% below baseline (DBAU–30%)
productivity would remain approximately
at the current level.
1. Lapola, D.M. et al. Nat. Clim. Change 4, 27–35 (2014).
2. Arima, E.Y., Barreto, P., Araújo, E. & Soares-Filho, B. Land Use
Policy 41, 465–473 (2014).
3. Agricultural Census 2006 (e Brazilian Institute of Geography
and Statistics, 2015);
4. FAO ST AT (Food and Agriculture Organization of the United
Nations, 2015);
5. Nepstad, D. et al. Science 344, 1118–1123 (2014).
6. Assad, E.D. et al. Biogeosciences 10, 6141–6160 (2013).
7. Cederberg, C., Meyer, D. & Flysjö, A. Life Cycle Inventory of
Greenhouse Gas Emissions and Use of Land and Energy in
Brazilian Beef Production (Swedish Institute for Food and
Biotechnology, 2009);
8. Parrotta, J.A. Agric. Ecosyst. Environ. 41, 115–133 (1992).
9. Ferraz, J.B. S. & de Felício, P.E. Meat Sci.
84, 238–243 (2010).
R. de Oliveira Silva1,2*, L. G. Barioni3, and
D. Moran1
1Research Division, SRUC, West Mains
Road, Edinburgh EH9 3JG, UK. 2School of
Mathematics, The University of Edinburgh,
Mayfield Road, Edinburgh EH9 3JZ, UK.
3Embrapa Agriculture Informatics,
CEP 13083-886 Campinas-SP, Brazil.
... However, it remains uncertain if high yield projections will lead to a decrease in the total agricultural area. Past records show that yield increase in the Cerrado biome did not result in a reduction of total agricultural area (Goulart et al., 2016). The correct implementation of agricultural policy, aiming at increasing the intensity of beef production, by means of the Forest Code, has shown that deforestation can decrease (Phalan et al., 2016). ...
Full-text available
Land use change (LUC) related GHG emissions determine largely if bioenergy is a suitable option for climate change mitigation. This study assesses how LUC emissions influence demand for bioenergy to mitigate GHG emissions, and how this affects the energy mix, using Brazil as a case study. A methodological framework is applied linking bioenergy supply curves, with associated costs and spatially explicit LUC emissions, to a bottom-up energy system model. Furthermore, the influence of four key determining parameters is assessed; agricultural productivity, time horizon, natural succession, and the use of dynamic emission factors. Demand for new bioenergy plantations range from 0.5-6.7 EJ in 2050, and is avoided when its emission factor (EF) reaches above 15 kg CO2/GJbiomass. Dynamic EFs result in earlier and larger use of bioenergy. Static EFs attenuate all emissions evenly over time, resulting in relative high emissions around 2050 when the carbon budget is most stringent. This in contrast to dynamic EFs, having early high peaks because of clearance of natural vegetation, but relatively small long-term emissions when the carbon budget is most stringent. Exclusion of natural succession, in combination with spared agricultural land, results in a demand of 6.7 EJ, because of its low carbon penalty. Assuming that land is spared due to continues yield increase (which is the reason to include natural succession as and EF component), bypasses the fact that yield improvements (that make those lands available) take place because of demand for bioenergy. When low carbon biomass is limited available, increasing electrification is observed, leading to electric capacity increase of 62% (mainly wind and solar energy), and a 12% energy system costs increase. Inclusion of spatio-temporal explicit supply potential and LUC emissions, leads to improved bioenergy deployment pathways that come closer to the real situation as the dynamic nature of LUC emissions is included.
... This does not mean that, in some specific historical conditions of capitalist society, a constitutionally legalized deceleration of the environmental destruction does not occur in Brazil (see some examples in Calmon et al., 2011;Scarano et al., 2012;Nepstad et al., 2014, Overbeck et al., 2015. However, what has been most often reported in the country by conservationists are ecological disasters and controversial actions by national leaders, which will increase CO 2 emissions and will cause a massive loss of species compromising the provision of ecosystem services, goods and human well-being (Metzger et al., 2010;Fearnside and Pueyo, 2012;Loyola, 2014;Overbeck et al., 2015;Fernandes et al., 2016;Goulart et al., 2016;Azevedo-Santos et al., 2017;Padial et al., 2017). ...
Brazilian biodiversity is being target of many scientific efforts to preserve it. However, there is an enormous contradiction in the country between what is discussed in scientific theory and what government measures are actually doing in practice. In this work, we discuss Brazil's conservationist aspirations under a human and social aspect, which the scientific view of natural scientists seldom explores: the historical materialist conception. From this analysis, we argue that current scientific efforts are important, but merely palliative, because at the heart of capitalist society the logic of value precedes any political decision making of the state. Therefore, the analysis of Brazilian biodiversity conservation under the premises of historical materialism elucidates with more clarity the forces that are at play in the country to inform the practice of conservation. This is a way of understanding the relatively ineffective role that science and technology has had in the permanent control of environmental destruction in Brazil.
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Land Sparing predicts that agricultural intensification is the best way to meet productive, humanitarian and conservation goals, and the recent prominence of this strategy on conservation and agricultural agendas is notable. The basic idea is that, by producing more, agriculture intensification can spare natural habitats from further agriculture expansion. Nevertheless, some authors have suggested that intensifying and increasing productivity may actually lead to increasing expansion of agricultural lands (Jevons Paradox). We test the association between agricultural yield on farmland expansion and on deforestation between 2000 and 2015 in 122 nations along the tropics, and in the main tropical regions. To this end we used Generalized Linear Models, as well as Panel Data to verify the effects of agricultural yield and socioeconomic variables on farmland expansion and deforestation. Greater yield increases lead to higher deforestation rates in Sub-Saharan Africa and Latin America and Caribbean and increasing yield average induces agriculture expansion in East Asia and Pacific, giving support to the Jevons Paradox hypothesis. On the other hand, we found a positive association between yield average and forest area change in the tropics, nevertheless, regression coefficients were very small, compared to other significant models. Therefore, Jevons Paradox seems to be more common than Land Sparing and increasing yields inducing deforestation rather than curbing it.
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Biodiversity conservation in heterogeneous landscapes faces the challenge of accounting for the complex interactions between the variation in species responses, existence of multiple habitats, diverse governance regimes, and anthropogenic threats. Yet, the scarcity of integrative studies still limits our understanding of the combined effects of social and ecological factors on biodiversity. We propose a framework for the management of heterogeneous landscapes that explicitly accounts for the interactive effects of governance regimes and anthropogenic threats on key landscape traits that affect biodiversity. We then apply the framework on bird conservation in the Espinhaço mountain range, an heterogeneous landscape composed of cerrado, forest and rupestrian grasslands, in the Southeast of Brazil. The model considered birds that inhabit these three type of environments, whose populations are influenced by habitat area, landscape integral connectivity and connectivity among strictly protected areas via multiple least-cost corridors. We assessed the effects of three governance regimes and three major threats on the aforementioned landscape traits for each bird group. The relative habitat area and integral connectivity for rupestrian grassland’s birds are more widely covered by strictly protected areas compared to those inhabiting cerrado and forest. Corridors among strictly protected reserves potentially used by the three bird groups are mostly found inside sustainable-use reserves. Mining and wood-cover loss affects mainly habitat area for forest birds, while fire endangers habitat for rupestrian grassland birds. The integrative framework proposed by our study can be applied elsewhere fostering an heuristic knowledge assisting scientists and practitioners for conserving highly complex landscapes.
Large-scale land governance and environmental monitoring are huge challenges for tropical countries with significant forest cover. In this discussion paper, we analyzed the conditions and achievements of the implementation of the Brazilian Rural Environmental Registry (CAR). CAR was an important breakthrough of the Native Vegetation Protection Law for environmental monitoring in Brazil. CAR is the mandatory and self-declaratory registry for rural properties. Owners must provide georeferenced delimitation of their property’s boundaries and legally protected areas, such as Areas of Permanent Preservation and Legal Reserves. We used the example of the State of Mato Grosso (transition between the two largest biomes in Brazil – Amazon and Cerrado) to discuss how CAR and its national information system (called SICAR) provide important inputs for land-use, environmental, economic, territorial, and food security policies. Future policies should include increasing investments and coordination between different sectors to integrate CAR and conservation efforts with agricultural production and sustainable management.
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Land-use change occurs nowhere more rapidly than in the tropics, where the imbalance between deforestation and forest regrowth has large consequences for the global carbon cycle. However, considerable uncertainty remains about the rate of biomass recovery in secondary forests, and how these rates are influenced by climate, landscape, and prior land use. Here we analyse aboveground biomass recovery during secondary succession in 45 forest sites and about 1,500 forest plots covering the major environmental gradients in the Neotropics. The studied secondary forests are highly productive and resilient. Aboveground biomass recovery after 20 years was on average 122 megagrams per hectare (Mg ha(-1)), corresponding to a net carbon uptake of 3.05 Mg C ha(-1) yr(-1), 11 times the uptake rate of old-growth forests. Aboveground biomass stocks took a median time of 66 years to recover to 90% of old-growth values. Aboveground biomass recovery after 20 years varied 11.3-fold (from 20 to 225 Mg ha(-1)) across sites, and this recovery increased with water availability (higher local rainfall and lower climatic water deficit). We present a biomass recovery map of Latin America, which illustrates geographical and climatic variation in carbon sequestration potential during forest regrowth. The map will support policies to minimize forest loss in areas where biomass resilience is naturally low (such as seasonally dry forest regions) and promote forest regeneration and restoration in humid tropical lowland areas with high biomass resilience.
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Expansion of land area used for agriculture is a leading cause of biodiversity loss and greenhouse gas emissions, particularly in the tropics. One potential way to reduce these impacts is to increase food production per unit area (yield) on existing farmland, so as to minimize farmland area and spare land for habitat conservation or restoration. There is now widespread evidence that such a strategy could benefit a large proportion of wild species, provided that spared land is conserved as natural habitat (1). However the scope for yield growth to spare land by lowering food prices and hence incentives for clearance (“passive” land sparing) can be undermined if lower prices stimulate demand, and higher profits per unit area encourage agricultural expansion, increasing the opportunity cost of conservation (2, 3). We offer a first description of four categories of “active” land-sparing mechanisms that could overcome these rebound effects by linking yield increases with habitat protection or restoration. The effectiveness, limitations and potential for unintended consequences of these mechanisms have yet to be systematically tested, but in each case we describe real-world interventions which illustrate how intentional links between yield increases and land sparing might be developed.
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African grasses used as forage are spreading fast in cerrado (Brazilian savanna) patches, probably displacing native species. An analysis of the graminoid species abundance was performed in Cerrado P-de-Gigante Reserve (So Paulo State, Brazil), where their relative frequency, density, dominance and the value of importance were assessed in two cerrado forms: cerrado sensu stricto (denser) and campo cerrado (open). Thirty-six transects were determined, along which 3240.5 m 0.5 m herbaceous samples were taken. Ordination by CCA analysis was performed to detect gradients in the graminoid species distribution, according to shading, distance from the reserve border and aspect. Interspecific associations among the species were tested. A total of 93 species were sampled, predominantly Poaceae and Myrtaceae families. Two alien grasses were found, Melinis minutiflora and Brachiaria decumbens, with very high values of importance. Light availability proved to be the most important analyzed environmental factor related to graminoid distribution, strongly correlated with the abundance of M. minutiflora. Both alien grasses were negatively associated with most native graminoids, suggesting they exert a strong competitive pressure on the native herbaceous community. Attention must be taken to the introduction of alien species in the country.
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Meta-analysis provides formal statistical techniques for summarizing the results of independent experiments and is increasingly being used in ecology. The response ratio (the ratio of mean outcome in the experimental group to that in the control group) and closely related measures of proportionate change are often used as measures of effect magnitude in ecology. Using these metrics for meta-analysis requires knowledge of their statistical properties, but these have not been previously derived. The authors give the approximate sampling distribution of the log response ratio, discuss why it is a particularly useful metric for many applications in ecology, and demonstrate how to use it in meta-analysis. The meta-analysis of response-ratio data is illustrated using experimental data on the effects of increased atmospheric CO{sub 2} on plant biomass responses.
Recent debate about agricultural greenhouse gas emissions mitigation highlights trade-offs inherent in the way we produce and consume food, with increasing scrutiny on emissions-intensive livestock products. Although most research has focused on mitigation through improved productivity, systemic interactions resulting from reduced beef production at the regional level are still unexplored. A detailed optimization model of beef production encompassing pasture degradation and recovery processes, animal and deforestation emissions, soil organic carbon (SOC) dynamics and upstream life-cycle inventory was developed and parameterized for the Brazilian Cerrado. Economic return was maximized considering two alternative scenarios: decoupled livestock–deforestation (DLD), assuming baseline deforestation rates controlled by effective policy; and coupled livestock–deforestation (CLD), where shifting beef demand alters deforestation rates. In DLD, reduced consumption actually leads to less productive beef systems, associated with higher emissions intensities and total emissions, whereas increased production leads to more efficient systems with boosted SOC stocks, reducing both per kilogram and total emissions. Under CLD, increased production leads to 60% higher emissions than in DLD. The results indicate the extent to which deforestation control contributes to sustainable intensification in Cerrado beef systems, and how alternative life-cycle analytical approaches result in significantly different emission estimates.
Natural resource consumption has increased considerably in the past 200 years despite more efficient technology advancements. This correlation between increased natural resource consumption and increased efficiency is known as Jevons’ Paradox. Since all the inputs to economic production come from the environment, increased resource consumption and ecosystem destruction should be of concern. Furthermore, the expenditure of natural resources to provide energy and other consumer goods is an irreversible process, worsening the human condition instead of improving human welfare as neoclassical theory would have one to believe. Therefore, sustainable development policies need to be considered to end the continued excess consumption, beyond sustainable levels, of natural resources and the potential resulting conflicts. To design environmentally sustainable policies, the effect of economic activity, of resource utilization, and increased efficiency must be understood. In this paper, we attempt to illustrate how human consumption of natural resources alters the natural state of the economy and the environment. Further, using energy data from the Energy Information Administration we develop models that provide some empirical support that Jevons’ Paradox may exist on a macro level. Finally, we examine the resulting policy implications and the applications for an ecological economic approach.
Among the myriad complications involved in the current food crisis, the relationship between agriculture and the rest of nature is one of the most important yet remains only incompletely analyzed. Particularly in tropical areas, agriculture is frequently seen as the antithesis of the natural world, where the problem is framed as one of minimizing land devoted to agriculture so as to devote more to conservation of biodiversity and other ecosystem services. In particular, the "forest transition model" projects an overly optimistic vision of a future where increased agricultural intensification (to produce more per hectare) and/or increased rural-to-urban migration (to reduce the rural population that cuts forest for agriculture) suggests a near future of much tropical aforestation and higher agricultural production. Reviewing recent developments in ecological theory (showing the importance of migration between fragments and local extinction rates) coupled with empirical evidence, we argue that there is little to suggest that the forest transition model is useful for tropical areas, at least under current sociopolitical structures. A model that incorporates the agricultural matrix as an integral component of conservation programs is proposed. Furthermore, we suggest that this model will be most successful within a framework of small-scale agroecological production.