Assessment of net ecosystem services of plastic greenhouse vegetable cultivation in China

Plastic greenhouse vegetable cultivation is rapidly expanding in China and elsewhere worldwide. In order to comprehensively understand the impacts of plastic greenhouse vegetable cultivation on agricultural ecosystem services and dis-services, we developed an assessment framework for the net ecosystem services and used China as a case study. Our results showed that, compared to conventional vegetable cultivation, plastic greenhouse vegetable cultivation has higher fresh vegetable production, greater CO₂ fixation (3.61 t CO₂ ha^− 1 yr^− 1), better soil retention (23.1 t ha^− 1 yr^− 1), and requires less irrigation (2132 m³ water ha^− 1 yr^− 1), maintains similar soil fertility, but also has higher NO₃⁻ accumulation and N₂O emissions. In 2004, plastic greenhouse vegetable cultivation in China provided an overall net economic benefit of 67,956 yuan ha^-1 yr^− 1 (8.28 yuan = 1 USD in 2004), where 68,240 yuan ha^− 1 yr^− 1 represented ecosystem services and 284 yuan ha^− 1 yr^− 1 for dis-services. The transition from conventional vegetable cultivation to plastic greenhouse vegetable cultivation resulted in a net economic benefit of 24,248 yuan ha^− 1 yr^− 1. A cost-benefit analysis suggests that plastic greenhouse vegetable cultivation in China has the potential to optimize social benefits in addition to increasing annual economic income to farmers directly.     

Integrating environmental and economic performance to assess modern silvoarable agroforestry in Europe

The environmental and economic performance of silvoarable agroforestry in Europe is highly variable. Multi-criteria analysis, using the PROMETHEE outranking approach, was used to evaluate the integrated performance of silvoarable agroforestry on hypothetical farms in nineteen landscape test sites in Spain, France, and The Netherlands. The silvoarable scenarios allocated a proportion of the hypothetical farms (10 or 50%) to silvoarable agroforestry at two different tree densities (50 or 113 trees ha^− 1) on two different qualities of land (best or worst quality land). The status quo (conventional arable farming) was also assessed for comparison. The criteria used in the evaluation (soil erosion, nitrogen leaching, carbon sequestration, landscape biodiversity, and infinite net present value) were assessed at each landscape test site; infinite net present value was assessed under six levels of government support. In France, the analysis showed, assuming equal weighting between environmental and economic performance, that silvoarable agroforestry was preferable to conventional arable farming. The best results were observed when agroforestry was implemented on 50% of the highest quality land on the farm; the effect of tree density (50-113 trees ha^− 1) was small. By contrast, in Spain and The Netherlands, the consistently greater profitability of conventional arable agriculture relative to the agroforestry alternatives made overall performance of agroforestry systems dependent on the proportion of the farm planted, and the tree density and land quality used.     

The social value of carbon sequestered in Great Britain's woodlands

The economic value of carbon storage associated with British woodland is calculated. Models were developed to estimate C flux associated with live trees, forest floor litter, soils, wood products, harvest, fossil fuel used in manufacturing and C displacement from biofuels and products for representative British plantation species: Sitka spruce (Picea sitchensis) and beech (Fagus sylvatica). Map databases of publicly and privately owned woodlands were compiled for Great Britain. Carbon flux was determined for individual woodland sites, and monetised using candidate parameters for the social discount rate (1, 3, 3.5 or 5%) and social value of carbon (US$109.5, $1, $10 or $17.10/t). A conventional discount function was applied. Final results are expressed as Net Present Values, for the base year 2001, with discounting commencing in 2002. The minimum suggested NPV (discount rate = 3% and social value of carbon = $1) of GB woodlands already existing in 2001 is $82 million, with a further $72 million that might be added by future afforestation. These figures rise dramatically if a discount rate of 1% and social value of sequestered carbon = $109.5/t are assumed. The calculated total value of C stored in British woodland depends significantly on parameter assumptions, especially about appropriate discount rate and social value of sequestered carbon.     

The projected costs and benefits of water diversion from and to the Sultan Marshes (Turkey)

The Sultan Marshes in the Develi Basin, Anatolia, one of twelve internationally important wetlands of Turkey, have been severely affected by the construction of an irrigation project in 1988. Intensive use of surface and ground water in irrigation has caused more than a 1 m decline in water levels and has affected the wetlands' ecological characteristics. Previous studies indicate that Sultan Marshes will need more water to restore viable ecological conditions. In this study, we analyze how economic benefits from agriculture and wetlands would be affected if moderate amounts of water were diverted from agriculture back to wetlands in the Develi Basin. By estimating total and marginal costs and benefits associated with water diversions, we determined the optimum or economically-efficient amount of water diversion. When only direct-use values of the wetland (animal grazing, plant harvesting, and ecotourism) were included in the analysis, the optimum amount of water diversion to the wetlands was found to be 5.2 million m³ year^− 1 (165 L sec^− 1), which compares to about 62 million m³ year^− 1 (1,957 L sec^− 1) used in irrigation. When wastewater treatment benefits (an indirect-use value) were added, the optimum amount rose to 7 million m³ year^− 1. Overall, the analysis showed that water diversion from agriculture to the Sultan Marshes is economically preferable.     

To settle or protect? A global analysis of net primary production in parks and urban areas

We test—at the global scale—the hypothesis that human beings tend to build settlements in areas of high biological productivity, and protect (as parks) areas of low productivity. Furthermore, we propose an alternative measure of the extent and effectiveness of the global protected areas network based on potential net primary production (NPP₀). The average NPP₀ in urban areas and parks is calculated and compared to the average NPP₀ of the geopolitical regions and biomes containing these areas. Additionally, human appropriation of net primary production (HANPP) in parks is used as an indicator of the effectiveness of these protected areas. We find that in almost all regions of the world, humans have chosen to settle in the most productive areas. At the global scale, urban areas have considerably higher NPP₀ (592 g Cm^− 2 yr^− 1) than the global average (494 g Cm^− 2 yr^− 1), while parks have roughly average NPP₀ (490 g Cm^− 2 yr^− 1). Parks with an IUCN category of I-VI account for 9.5% of the planet's terrestrial NPP₀, compared to 9.6% of its terrestrial area. Although protected area and protected NPP₀ are nearly equal, this equivalence is diminished by HANPP within parks. Globally, the average HANPP in all protected areas is 14% of their NPP₀, and HANPP within parks increases as the park management category becomes less restrictive. Moreover, we find a positive correlation between HANPP in parks and the extent of urbanization in the surrounding region and biome. Area-based targets for conservation provide no information on either the quality of the areas we choose to protect, or the effectiveness of that protection. We conclude that NPP₀ and HANPP may provide an additional, useful tool for assessing the extent and effectiveness of the global protected areas network.     

Valuing ecosystem goods and services: a new approach using a surrogate market and the combination of a multiple criteria analysis and a Delphi panel to assign weights to the attributes

A new approach to valuing ecosystem goods and services (EGS) is described which incorporates components of the economic theory of value, the theory of valuation (USappraisal), a multi-model multiple criteria analysis (MCA) of ecosystem attributes, and a Delphi panel of experts to assign weights to the attributes. The total value of ecosystem goods and services in the various tenure categories in the Wet Tropics World Heritage Area (WTWHA) in Australia was found to be in the range AUD$188 to $211 million year⁻¹, or AUD$210 to 236 ha⁻¹ year⁻¹ across tenures, as at 30 June 2002. Application of the weightings assigned by the Delphi panelists and assessment of the ecological integrity of the various tenure categories resulted in values being derived for individual ecosystem services in the World Heritage Area. Biodiversity and refugia were the two attributes ranked most highly at AUD$18.6 to $20.9 million year⁻¹ and AUD$16.6 to $18.2 million year⁻¹, respectively.     

Economic implications of maintaining rangeland ecosystem health in a semi-arid savanna

A simulation model was used to determine the ecological and economic consequences of managing stocking rate on semi-arid savanna rangeland continuously stocked with livestock to achieve the alternate management goals: (1) maintaining current range condition, (2) maximizing profit, or (3) improving range condition over a 30-year time frame. We developed values for end of the year herbaceous standing crop and utilization required to attain these management goals for rangeland in poor to excellent condition. Based on extensive field research conducted in this region over 5 decades, range condition in this model is programmed to decline in response to three factors: excessive grazing pressure, below average precipitation, and an increase in woody plants. Earning capacity is four times higher for range in excellent condition than that in poor condition. For all initial range condition (RC) values, simulated stocking rates that maintained RC resulted in simulated mean weaning weights 93-94% of maximum. Maximum short-term and long-term profit is attained at higher stocking rates than would maintain long-term range condition and at much higher levels than would increase range condition levels. When stocked for maximum profit, individual animal performance was 90% of maximum. The model predicts that low stocking rates allow range condition to improve. At these recovery stocking rates, total 30-year profits were found to be 78%-87% of the stocking rates that would maintain range condition, and only 67%-75% of stocking rates that would maximize profit. Predictions of the end of year standing crop to maintain range condition were in broad agreement with the 1000 kg ha^− 1 advised for this region. To improve range condition, the model predicts that an end of year standing crop of 1500-2000 kg ha^− 1 is required, compared to the generally advised level of 1200-1500 kg ha^− 1. The predicted end of year forage standing crops for the maximum profit goal are well below the advised 800 kg ha^− 1 threshold required to prevent degradation for all of the initial range conditions that were simulated. To ensure maintenance of range in excellent condition, our results concur with the advised utilization levels of 20-25%. However, for range in poorer than excellent condition, the model predicted much lower utilization levels were needed to maintain or improve range condition.     

The economic impacts of river rehabilitation: A regional Input-Output analysis

We developed a model to predict the impacts of river rehabilitation activities on the local economy. The model is based on the Input-Output analysis technique and was applied to the planned rehabilitation project for the River Thur in northern Switzerland, along the 4 km stretch between the communities of Bürglen and Weinfelden. We estimated changes in local employment and local economic output resulting from government spending on rehabilitation, associated changes in adjacent land use, and increased recreational activity. Accounting for land use changes required a modification of the conventional Input-Output analysis technique which should be of general interest. We accounted for uncertainty in the data and in some of the model assumptions by using a probabilistic formulation and propagating uncertainty through the model equations. As time-consuming local surveys were beyond the scope of this study, we used the Location Quotient non-survey technique to construct the local technical coefficients from national data and local employment data. This implies that the model can be applied quite easily to a different study area in Switzerland as long as local employment data are available. For each CHF 1 million expenditure per year on rehabilitation activities in our study region, we estimate an extra 8 fulltime employment equivalents (standard deviation, σ = 0.4 fte) and an increased output of CHF 1.4 million (σ = CHF 0.05 million). The low uncertainty of these estimates can be partly attributed to the structure of Input-Output analysis and partly to the fact that we estimated changes in the economic output, rather than output itself. In addition to the above impacts, we estimate that increased recreational use of the area will increase output by as much as CHF 0.17 million (σ = CHF 0.12 million) and employment by as much as 1.7 fulltime employment equivalents (σ = 1.3 fte), depending on the specific rehabilitation option selected.     

An assessment of two environmental and economic benefits of ‘Cash for Clunkers’

This research aims to provide a more comprehensive, life cycle accounting of two categories of environmental and economic benefits associated with the $3 billion US “Cash for Clunkers” vehicle scrappage program. First, using a life cycle emissions methodology developed in Lenski et al. (2010), we find that about 29,000 metric tons of criteria pollutant emissions were avoided, for a benefit of about $23 million; avoided carbon dioxide emissions, by comparison, provided a benefit worth $90 million. Second, we compare the market value of scrapped vehicles to the rebates provided, calculating the consumer surplus or “gift” to participants to be up to $2 billion (about $2000 to $3000 per vehicle). This is significantly more than offered in previous vehicle scrappage programs, and suggests opportunities to get more environmental and economic “bang for the buck.” Finally, these two categories of benefits are found to be heavily concentrated geographically around urban centers. About 2% of US counties (50 counties) received 50% and 30% of the aggregate benefits from avoided criteria pollutant emissions and consumer surplus from the rebates, respectively.     

Estimated annual and lifetime labor productivity in the United States, 2016: implications for economic evaluations

Abstract

Background: Human-capital based lifetime productivity estimates are frequently used in cost-of-illness (COI) analyses and, less commonly, in cost-effectiveness analyses (CEAs). Previous US estimates assumed that labor productivity and real earnings both grow by 1% per year.

Objectives: This study presents estimates of annual and lifetime productivity for 2016 using data from the American Community Survey, the American Time Use Survey, and the Current Population Survey, and with varying assumptions about real earnings growth.

Methods: The sum of market productivity (gross annual personal labor earnings adjusted for employer-paid benefits) and the imputed value of non-market time spent in household, caring, and volunteer services was estimated. The present value of lifetime productivity at various ages was calculated for synthetic cohorts using annual productivity estimates, life tables, discount rates, and assumptions about future earnings growth rates.

Results: Mean annual productivity was $57,324 for US adults in 2016, including $36,935 in market and $20,389 in non-market productivity. Lifetime productivity at birth, using a 3% discount rate, is roughly $1.5 million if earnings grow by 1% per year and $1.2 million if future earnings growth averages 0.5% per year.

Conclusions: Inclusion of avoidable productivity losses in societal-perspective CEAs of health interventions is recommended in new US cost-effectiveness guidelines. However, estimates vary depending on whether analysts choose to estimate total productivity or just market productivity, and on assumptions made about growth in future productivity and earnings.