城市水系生态系统服务功能研究

水系是城市最宝贵的自然要素之一,它具有水利、航运、生态、旅游游憩、历史文化、纳污等多种生态系统服务功能,其生态系统服务功能的保护应包括严格控制水系污染和破坏、保护水系的各种自然过程、开发水系的旅游游憩功能和保护滨水区的历史文化特色。     

Modelling the supply of ecosystem services from agriculture: a minimum‐data approach*

We argue that to support agriculture–environmental policy decision making, stakeholders need ‘quantitative back‐of‐the‐envelope’ analysis that is timely and sufficiently accurate to make informed decisions. We apply this concept to the analysis of the supply of ecosystem services from agriculture. We present a spatially explicit production model and show how it can be used to derive the supply of ecosystem services in a region. This model shows that the supply of ecosystem services can be derived from the spatial distribution of opportunity cost of providing those services. We then show how this conceptual model can be used to develop a minimum‐data (MD) approach to the analysis of the supply of ecosystem services from agriculture that can be implemented with the kinds of secondary data that are available in most parts of the world. We apply the MD approach to simulate the supply of carbon that could be sequestered in agricultural soils in the dryland grain‐producing region of Montana. We find that the supply curve derived from the MD approach can approximate the supply curve obtained from a more elaborate model based on site‐specific data, and can do so with sufficient accuracy for policy analysis.     

Managing conflicting goals in pig farming: farmers' strategies and perspectives on sustainable pig farming in Sweden

Industrial meat production has several negative environmental effects. Governments’ agricultural policies aim for cost efficiency combined with high environmental and animal welfare, which puts farmers in a difficult situation trying to navigate between sometimes contradictory requirements. This paper studies how Swedish pig farmers resolve or cope with conflicting goals in pig farming. We have analysed the regulations governing EU and Swedish pig farming. We have also interviewed five Swedish pig farmers about their views of the different goals of pig farming and strategies for resolving conflicts between the goals of low environmental impact, high animal welfare and enough profitability to continue farming. The greatest divide was between the conventional farmers, who emphasized natural resource efficiency, and the organic farmers who stressed animal welfare, multifunctionality and ecosystem service delivery. We suggest four strategies to contribute to resolving some of the conflicting goals: improve communication about different types of pig farming; use public procurement as a driver towards more sustainable pork production; work towards improving the Common Agricultural Policy, perhaps by implementing payments for ecosystem services or multifunctionality; and finally, decrease the total production of pork to lower the emissions per land unit.     

Making explicit agricultural ecosystem service trade-offs: a case study of an English lowland arable farm

European farmland hosts a species assemblage of animals and plants which have undergone declines through the late twentieth and early twenty-first centuries, at least partly as a result of increased productivity. Further increases in human populations, changes in availability and cost of raw materials, policy constraints, price volatility and climatic changes will further drive greater efficiency and high yields in agriculture, with the risk of further adverse environmental impacts. We assess the effects of different management priorities (production-driven cropping vs. wildlife-friendly farming) at an arable farm in eastern England on food production, greenhouse gas (GHG) emissions and biodiversity. We modelled one actual and three alternative cropping scenarios using actual yields from the farm over 13 years, to calculate total yields and those foregone for agri-environmental measures. We measured crop yields, relative abundance of 19 farmland bird species, and CO₂ and N₂O emissions related to crop production. Removing up to 10.5% of land from production coupled with a more diverse rotation (including legumes) resulted in a large increase in breeding birds (177%) and reduction of 9.4% in GHG emissions at the cost of 9.6% of food energy. Food protein lost was only 2.9%. A smaller increase in bird numbers of 50% could be achieved at a much smaller cost to yield (～1.7% energy or protein) but with correspondingly smaller emissions reductions (1.2%). Results are discussed within the context of continued biodiversity loss to agriculture, increasing food demand and changing diets.     

Dynamics of Agricultural Technology Adoption: Age Structure, Reversibility, and Uncertainty

We develop a dynamic model of technology adoption that generalizes previous literature by incorporating technology age, reversible investment, variable inputs and outputs, and stochastic prices. The model is calibrated for irrigated cotton production in California. Optimal investment exhibits a significant vintage capital effect which provides a new candidate explanation for delayed technology diffusion. We show that the hurdle rate derived by option value models can be partially explained by the assumption of irreversible investment, and simulations demonstrate this assumption has regional policy relevance. Uncertainty affects optimal investment but has a declining effect with technology age.     

Estimating loss of ecosystem services due to paddy straw burning in North-west India

Crop residue burning is severe in rice–wheat cropping system of North-western states (Punjab, Haryana, Uttarakhand, and western Uttar Pradesh) of India, where mechanized harvesting of rice using combine harvesters is a common practice, and management of leftover residue in the short window of 10–15 days for timely sowing of wheat is a formidable task. Moreover, there is a lack of user-friendly, cost-effective, and economically viable options and, around 23 million tonnes of rice residue is burnt annually in the region. Burning biomass not only pollutes environment but also results in loss of appreciable amount of plant’s essential nutrients. Straw burning releases soot particles, nitrogen oxides, sulphur dioxide, carbon dioxide, carbon monoxide, and polycyclic aromatic hydrocarbons, thus causing serious deterioration in atmospheric quality and human health hazards. We attempted to identify and quantify the environmental cost of paddy straw burning in North-west India. Using extant coefficients, it is estimated that cost of paddy residue burning is INR (Indian National Rupee) 8953?per?ha, and the social cost of burning is INR 3199 crores per annum in the region.     

Forest governance and economic values of forest ecosystem services in Vietnam

Forest ecosystems deliver valuable services to humanity. However, many forests are being degraded and their services have been undervalued. The main problem lies in the inadequate institutional arrangements for forest governance. This paper aims to assess the effects of alternative forest governance arrangements on the provision and economic values of forest ecosystem services (FES) in Vietnam. The study presents a framework for mapping land use and land cover (LULC) change stemming from actual and hypothetical changes in forest governance regimes, quantifies the resulting changes in the provision of FES, and estimates the associated economic values. In the context of the study site in the North Western uplands of Vietnam, we test three alternative forest governance scenarios: business as usual, with a dominant government role; a community-based governance regime; and a private, individual-based forestry governance regime. Scenarios are based quite closely on the way these regimes are (or might be expected to be) implemented in Vietnam. For each forest governance scenario, we map LULC changes based on land suitability analysis and transition likelihood for the period 2010 − 2020. The resulting maps are used as inputs into the InVEST (Integrated Valuation of Environmental Services and Tradeoffs) model, which is used to estimate the quantity of three specific FES: carbon storage/sequestration, sediment yield, and water yield. We apply economic valuation methods to value these services: the social cost of carbon is used to estimate the economic values of carbon storage/sequestration; the cost of removing sediment deposited in reservoirs is applied for valuing the reduction of sediment yield, and the residual value of water supply for hydropower generation is used for valuing water yield. The results show that forest governance regimes have a significant effect not only on forest LULC, but also on the quantity and values of FES derived from forests. The FES are differentially affected by alternative forest governance regimes: some FES increase in quantity and value under some governance regimes and decrease under others. Of the three forest governance regimes examined, there is no one regime that will always be ‘better’ than the others in terms of provisioning all considered FES. For the specific context of Vietnam, we find that the private forest governance scenario is inferior to the community-based governance scenario, as an alternative to the current state-based governance. Because our results pertain to the scenarios as constructed, rather than generally to broad categories of governance regimes, there remains the possibility that regimes can be constructed that outperform all of those examined here.     

广州市流溪河流域白云区段生态系统服务价值

分析了流溪河流域白云区段生态系统的景观变化和生态环境现状，依据该段的土地详查数据(1993年)及其土地利用变更调查数据(2001年末)，引用Constanza等对全球生态系统服务单位公顷价值的平均估算结果，对流溪河流域白云区段生态系统服务价值进行评估；2001年流溪河流域白云区段生态系统服务的总价值为85190050．43美元，折合人民币70700．75万元，相当于该区域同期GDP的6．22％；由于存在一些影响核算结果准确性的因素，该结果是粗略与保守的估算。     

Farmers' adoption of ecological practices: A systematic literature map

Understanding the factors associated with adoption of ecological farming practices is a well-established topic of interest to agricultural economists. As the transition to more sustainable agriculture has become a policy priority for the European Union, broad and balanced reviews of this literature are important. We develop a systematic map of quantitative observational studies which describes the ecological practice(s) adopted, the frequency of inclusion and significance of a range of independent variables, and how the dependent variable is measured. We also conduct a quality assessment. We find that while socio-demographic variables and farm structural variables are frequently included, they were insignificant more often than they were significant. For behavioural factors we find stronger evidence for the importance of cognitive or attitudinal variables compared to dispositional attitudinal variables. We also find a growing interest in social factors which will be valuable for researchers to explore further and reflect on the policy implications of our findings.     

基于生态服务价值的东江源区生态补偿标准研究

利用Costanza等对生态系统服务价值估算的原理,分析东江源区生态系统的主要服务功能,界定东江源区生态系统服务功能价值的补偿范围;在借鉴前人评估结果的基础上,完善东江源区生态系统服务价值评估,并计算补偿标准,为东江源区实施生态补偿提供理论依据。     

Notions of justice in payments for ecosystem services: Insights from China's Sloping Land Conversion Program in Yunnan Province

China's Sloping Land Conversion Program (SLCP) pays millions of farmers to convert cropland in upper watersheds to tree plantations. It is considered one of the world's largest payments for ecosystem services (PES) scheme for its reliance on financial incentives. This paper examines the outcomes of the SLCP by way of a case study from the Yangliu watershed in Yunnan province. It focuses on the notions of justice embedded in state policy and held by villagers and local state officials in order to understand the observed outcomes in terms of people's participation in the implementation of the SLCP, land use changes and livelihood effects. Villagers, local state officials, and state policy share a primary concern about distributive justice despite significant differences in their specific notions. The shared concern underlies the villagers’ positive reactions to the SLCP, which among other factors, have led to the intended expansion of tree plantations and a livelihood transition in Yangliu since 2003. The insights from Yangliu suggest the need to consider justice for a fuller understanding of the dynamics and outcomes of the SLCP and other PES schemes worldwide as the notions of justice applied by the involved actors may influence land use and livelihood dynamics in addition to the other factors considered in research this far.     

Minimum‐data analysis of ecosystem service supply in semi‐subsistence agricultural systems

Antle and Valdivia (2006, Australian Journal of Agricultural and Resource Economics 50, 1–15) proposed a minimum‐data (MD) approach to simulate ecosystem service supply curves that can be implemented using readily available secondary data and validated the approach in a case study of soil carbon sequestration in a monoculture wheat system. However, many applications of the MD approach are in developing countries where semi‐subsistence systems with multiple production activities are being used and data availability is limited. This paper discusses how MD analysis can be applied to more complex production systems such as semi‐subsistence systems with multiple production activities and presents validation analysis for studies of soil carbon sequestration in semi‐subsistence farming systems in Kenya and Senegal. Results from these two studies confirm that ecosystem service supply curves based on the MD approach are close approximations to the curves derived from highly detailed data and models and are therefore sufficiently accurate and robust to be used to support policy decision making.     

Effects of payments for ecosystem services programs in China on rural household labor allocation and land use: Identifying complex pathways

Payments for Ecosystem Services (PES) is increasingly used in developing countries to secure the sustainable provision of vital ecosystem services. The largest PES programs in the world are embedded in China’s new forest policies, which aim to expand forest cover for soil and water conservation and improve livelihoods of rural people. The objective of this study is to identify the complex pathways of the impacts of two PES programs , the Conversion of Cropland to Forest Program (CCFP) and the Ecological Welfare Forest Program (EWFP), on household livelihood decisions, and to quantify the direct and indirect impacts along the identified pathways. We fulfill this objective by developing an integrated conceptual framework and applying a Partial Least Squares-Structural Equation Model (PLS-SEM), based on household survey data from Anhui, China. Labor allocation (for on-farm work, local paid work, local business, or out-migration) and land use decisions (i.e., rent in, maintain, rent out, or abandon cropland) for participating households are key to understand PES program effects on livelihoods. Results show that the PES programs have only small direct effects but significant indirect effects via the mediating factor of capital assets. Moreover, group heterogeneity analysis shows that lower-income households do not benefit more than the better-off households from the PES programs, while households with medium wealth increase dependence on agriculture. In addition, household demographics, individual attributes, and geographic settings differ in their impacts on labor allocation and land use decisions. We conclude that CCFP and EWFP would be more efficient in conserving the environment while improving the economic welfare of lower-income households if capital assets were taken into account in the design of compensation schemes.     

Impact of local payments for ecosystem services on land use in a developed area of China: A qualitative analysis based on an integrated conceptual framework

Payments for ecosystem services (PES) have increasingly been applied as economic incentives for improving ecosystem services around the world. However, due to difficulties in measuring and attributing ecosystem services provisioning, a land-based approach has been popularly adopted as a proxy for the desired ecosystem services. In this study, we demonstrate the impact mechanism and outcomes of locally financed PES programs on conservation-based land use in a developed area of China. We present this work using a PES-land use proxy framework that is examined empirically through a variety of qualitative assessments. Our framework illustrates that, within the ecological, socioeconomic, and institutional conditions of developed areas, land use class, pattern and function would be impacted by (a) conservation effect, (b) stakeholder response, and (c) institutional adaptation mechanisms of local PES programs, with multiple land use trends as potential outcomes. We examine the framework using materials from Suzhou, China, which has implemented a top-down, partly involuntary (ecosystem services supply side), land based PES program. Our results show that, expected land use class, land use pattern and land use function are observed in areas where the PES programs were implemented. We also find that the conditions of developed areas and locally financed payments mechanism indeed played a crucial role in promoting conservation-based land use in Suzhou.     

Adoption of Agricultural E-Marketing: Application of the Theory of Planned Behavior

In this study, the authors used the theory of planned behavior (TPB) as a base model to determine how attitudes, subjective norms, and perceived behavioral control predict the intention of agricultural services professionals to adopt e-marketing of agricultural commodities. A convenient sample of 146 professionals from the public (n?=?61) and private sectors (n?=?85) were surveyed. Overall, results showed that the TPB model explained 94% and 71% of the variation in behavioral intent for public professionals and private professionals, respectively, with the remaining 6% and 29% relating to the other factors. Results for the public professionals showed that subjective norm and perceived behavioral control have a more important effect on adoption and that the effect of attitude was very small among professionals in private sector. Both groups selected the information services model as an appropriate in agricultural electronic marketing for local farmers so that agricultural services firms can offer only information services of farmers’ products without a direct role in buying and selling. Based on the results, it is recommended that to accelerate the adoption of e-marketing, its user-friendliness and advantages should be demonstrated to users via different platforms such as video presentations and workshops. In addition, the technology should be made available to potential users, and they should be encouraged and motivated to use it to ensure efficiency in the processing of transactions.     

The Dynamics of Agricultural Biotechnology Adoption: Lessons from series rBST Use in Wisconsin, 1994–2001

This article exploits panel data from Wisconsin dairy farmers to examine the dynamics of recombinant bovine somatotropin (rBST) adoption and to identify the characteristics that distinguish among nonadopters, disadopters, and early and late adopters. Panel methods are used to control for omitted variables and endogenous regressors that call into question coefficient estimates derived from cross-section adoption models. The results, however, confirm previous findings that larger farms with complementary feeding technologies are more likely to adopt rBST, nonadopters appear quite unlikely to become adopters, and rBST adoption will remain at rather moderate levels in Wisconsin.     

Assessing the financial contribution and carbon emission pattern of provisioning ecosystem services in Siwalik forests in Nepal: Valuation from the perspectives of disaggregated users

Provisioning Ecosystem Services (PS) from the forests contribute much to peoples’ livelihoods as well as to the national economy. Previous studies have been constrained by their primary focus on biophysical quantification of PS through modelling and mapping or aggregated monetary valuation, while little attention has been paid to the issues of the distribution of financial benefits among the different forest subgroups. Using market price and substitute good price methods, this paper assesses how local users exploit financial benefits and emit carbon from the use of PS in two dominant community-based forest management systems (community forestry—CF and collaborative forestry—CFM) based on proximity (nearby vs. distant users) and socio-economic class (rich vs. poor users) in the Siwalik region, Nepal. Results indicated that the wealth level of the users plays a key role in the amount of financial benefits generated from the use of PS: (1) users living near forests receive the highest economic benefits compared to those living long distances from the forest area. However the distribution of benefits differs according to management modality and socioeconomic status; (2) CF users, on average, receive higher economic benefits than CFM users; and (3) compared to poor households, rich households receive higher benefits. On average, a rich household adjacent to CF receives USD 1214/year while a poor household living in the same area receives almost half of that (USD 630/year). Similarly, a poor household living far from a forest area generates USD 189/year, slightly higher than that of a rich household in the same area (USD 109/year); and (4) an average CF user emits more carbon (7.4 tCO₂/HH/year) from the consumption of PS than an average CFM user (5 tCO₂/HH/year). Finally, we discuss the reasons behind these differences and draw policy implications for developing and refining constitutions and operational plans of forest user groups.