178 research outputs found
From Workers to Owners: Survey Evidence on the Impact of Property Rights Reforms on Small Farmers in Two Regions in Romania
In Romania, the 1991 Land Reform marked the beginning of a series of transformations in the ownership structure and the production system in agriculture. Nevertheless, after recently joining the EU it became evident that the agricultural sector is in need of major improvements in performance. We present preliminary findings from a unique village-level panel data at household level. Preliminary findings suggest that there are wide regional differences in terms of agricultural performance and organizational forms. Also, we find that productivity levels do not differ significantly between farming arrangements, and that labor supply, capital endowment, and contractual arrangements might be more important.http://deepblue.lib.umich.edu/bitstream/2027.42/64427/1/wp905.pd
A Net Energy-based Analysis for a Climate-constrained Sustainable Energy Transition
The transition from a fossil-based energy economy to one based on renewable
energy is driven by the double challenge of climate change and resource
depletion. Building a renewable energy infrastructure requires an upfront
energy investment that subtracts from the net energy available to society. This
investment is determined by the need to transition to renewable energy fast
enough to stave off the worst consequences of climate change and, at the same
time, maintain a sufficient net energy flow to sustain the world's economy and
population. We show that a feasible transition pathway requires that the rate
of investment in renewable energy should accelerate approximately by an order
of magnitude if we are to stay within the range of IPCC recommendations
From Workers to Owners: Survey Evidence on the Impact of Property Rights Reforms on Small Farmers in Two Regions in Romania
In Romania, the 1991 Land Reform marked the beginning of a series of transformations in the ownership structure and the production system in agriculture. Nevertheless, after recently joining the EU it became evident that the agricultural sector is in need of major improvements in performance. We present preliminary findings from a unique village-level panel data at household level. Preliminary findings suggest that there are wide regional differences in terms of agricultural performance and organizational forms. Also, we find that productivity levels do not differ significantly between farming arrangements, and that labor supply, capital endowment, and contractual arrangements might be more important.transition, land reform, property rights, productivity, Romania.
Nitrate attenuation in a restored river floodplain system: River Cole (Oxfordshire - UK)
PhDRestoring river-floodplain connectivity has been proposed as an alternative management
measure for natural flood defence through the temporary storage of floodwaters and the
attenuation of flood peaks downstream. Whilst several studies have documented the
associated ecological and landscape amenity values of such hydrological measures, the
water quality benefits to the adjacent water bodies have been inadequately studied. To
date, the focus of scientific research and natural resource management has been on the
role of riparian buffer zones for the alleviation of agricultural diffuse nitrate pollution.
This research investigated the potential for nitrate attenuation in a restored riverfloodplain
system, the River Cole (Coleshill, England), with the aim of informing future
restoration schemes of the best management practices for enhanced nitrate removal.
Following restoration, the increased river-floodplain connectivity has encouraged
overbank flooding of the different land use zones throughout the year. The flood pulse
supplies the floodplain soil with river water nitrate and creates the necessary anaerobic
conditions for the effective removal of nitrate via heterotrophic denitrification, while
organic carbon is supplied mainly through the traditional land use management
practices of grazing and mowing. The conservation of nitrogen via DNRA is of minimal
importance in this lowland agricultural catchment setting, mainly due to the nonlimiting
nitrate supply from the surrounding agricultural land but also the intermittent
saturation regime that restricts the low redox conditions to the low elevation riparian
areas. This presents the added benefit of restricting methane emission to the more
frequently waterlogged riparian soils, while denitrification is effective across the whole
floodplain area. Additionally, more than 90% of nitrate removal occurs in the top 30 cm
of the soil during the flood, while the role of subsurface denitrification is restricted by
the limited availability of organic carbon and nitrate. Based on these findings, this study
demonstrates that, for similar catchments, the nitrate removal capacity of a floodplain
can be assessed by the denitrification capacity of the surface soil. The assessment of the
denitrification capacity can be undertaken inexpensively using a simple empirical model
that requires a single microbial denitrification potential measurement, and a seasonal or
monthly record of soil nitrate content, soil moisture, and temperature. Assessments can
be undertaken as part of the design process to optimise nitrate removal or post
restoration to appraise the functioning of the scheme
Strategies in Enterprise Ecology: Symbiotic Models for Commercial Aviation as an Enterprise of Enterprises
Student research poste
A framework for defining sustainable energy transitions:principles, dynamics, and implications
While partial energy transitions have been observed in the past, the complete transition of a fossil-based energy system to a sustainable energy one is historically unprecedented on a large scale. Switching from an economy based on energy stocks to one based on energy flows requires a social paradigm shift. This paper defines Sustainable Energy Transition (SET) and introduces a set of five propositions that prescribe its sustainability. The propositions are comprehensive, spanning environmental constraints, resource availability, equity, and the transition dynamics from an energy and economic accounting perspective aimed at addressing all three pillars of sustainability. In order to rigorously define the constraints of SET a theoretical energy economy framework is introduced along with the concept of the renewable energy investment ratio. The paper concludes with a practical application of the SET propositions on the global energy system and identifies an order of magnitude underinvestment in the renewable energy investment ratio in comparison to the estimated level needed for a controlled transition that satisfies all propositions. The option of drastically increasing this ratio in the future may not be available as it would reduce societally available energy, imposing unacceptably high energy prices that would induce either fossil resource extraction beyond the safely recoverable resources or energy poverty
Game Theory Analysis of the Impact of Single Aisle Aircraft Competition on Fleet Emissions
To meet aviation’s CO2 emission reduction targets while maintaining mobility in the face
of increasing effective fuel costs, technology innovation will be required. The single aisle
commercial aircraft market segment is the largest by quantity and value, but has the longest
running product lines. New aircraft programs offer the largest potential gains in fuel
efficiency, but are risky and require large capital investments. Re-engining existing
airframes reduces risk and capital requirements, but offers lower potential fuel burn
improvements. Incremental improvements to existing aircraft lines may entail the lowest
risk. It is hypothesized that competition has important effects on manufacturers’ decisions to
innovate and that these effects must be considered when designing policies to reduce CO2
emissions from aviation. An aircraft program valuation model is developed to estimate
expected payoffs to manufacturers under different competitive scenarios. A game theory
analysis demonstrates how the incentives for manufacturers to innovate may be altered by
subsidies, technology forcing regulations, increased effective fuel costs, the threat of new
entrants, and long-term competitive strategies. It is shown that increased competition may
result in incumbent manufacturers producing re-engined aircraft while increased effective
fuel costs may result in new aircraft programs. Incumbents’ optimal strategies may be to
delay the entry into service of new single aisle aircraft until 2020-24, unless technology
forcing regulations are implemented.Mubadala Development Co
Strategies in Enterprise Ecology: Symbiotic Models for Commercial Aviation as an Enterprise of Enterprises
Agenda:
• Hypotheses
• Background
– Commercial Aviation Cycles
– Enterprises and business cycles
• A framework: Enterprise of Enterprises
• Modeling Enterprise of Enterprises
• Countercyclical strategies and symbiosi
- …