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1.
The application of lime or liming materials to acid-soil grasslands might help mitigate soil acidity, a major constraint to forage productivity in many temperate mountainous grasslands. Nowadays, in these mountainous grasslands, it is essential to promote agricultural practices to increase forage yield and nutritive value while preserving biodiversity and agroecosystem functioning. Two different field experiments were conducted in the Gorbeia Natural Park, northern Spain: (i) one in a calcareous mountainous grassland (Arraba) and (ii) the other in a siliceous mountainous grassland (Kurtzegan) to study the effects of a single application of two liming products, i.e. 2429 kg lime (164.3% CaCO3) ha?1 and 4734 kg calcareous sand (84.3% CaCO3) ha?1, applied one month before the beginning of the sheep grazing season (May–October), on soil chemical (pH, organic C, total N, C/N ratio, %Al saturation, Olsen P, exchangeable K+ and Ca2+) and biological parameters (dehydrogenase, β-glucosidase, urease, acid phosphatase and arylsulphatase activity) as well as on botanical diversity (graminoids, forbs, shrubs) and forage yield and nutritive value (crude protein, modified acid detergent fibre, digestibility). Untreated control plots were also included in the experiment. Soil sampling was carried out at the end of the sheep grazing season (6 months after liming treatment), while botanical composition was determined one year after treatments application. Although no increase in soil pH was observed in Arraba, liming significantly increased dehydrogenase activity (an indicator of soil microbial activity) by 30.4 and 86.7% at Arraba and Kurtzegan site, respectively. Liming treatments significantly improved forage yield and nutritive value in Arraba but not in Kurtzegan. Furthermore, no differences in soil biological quality, evaluated using the “treated-soil quality index” as proposed in this work, were observed between treated and untreated soils, and between the two different lime treatments (lime, calcareous sand). It was concluded that, in acid-soil temperate mountainous grasslands, moderate liming treatments have no negative short-term effects either on soil quality or botanical composition, while resulting in improvements in forage yield and nutritive value under some conditions.  相似文献   

2.
There are several claims in the literature that social desirability concerns affect people’s response to self-reported measures of environmental attitudes and ecological behaviour. However, only a few empirical studies have indirectly evaluated the impact of social desirability on environmental issues measures, and those who did have found only a low impact. This article describes two studies that explicitly address whether socially desirable responding has direct and moderating effects on self-reported environmental attitudes and ecological behaviour. Results from correlational and moderated multiple regression analyses from both studies showed that social desirability had only a weak direct effect on environmental attitudes (but not ecological behaviour), and had no moderating effect on the environmental attitudes–ecological behaviour relationship. Implications of these findings for research on environmental issues are discussed.
Taciano L. MilfontEmail:
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3.
Food production and consumption cause significant environmental burdens during the product life cycles. As a result of intensive development and the changing social attitudes and behaviors in the last century, the agrofood sector is the highest resource consumer after housing in the EU. This paper is part of an effort to estimate environmental impacts associated with life cycles of the agrofood chain, such as primary energy consumption, water exploitation, and global warming. Life cycle assessment is used to investigate the production of the following citrus-based products in Italy: essential oil, natural juice, and concentrated juice from oranges and lemons. The related process flowcharts, the relevant mass and energy flows, and the key environmental issues are identified for each product. This paper represents one of the first studies on the environmental impacts from cradle to gate for citrus products in order to suggest feasible strategies and actions to improve their environmental performance.
Marina Mistretta (Corresponding author)Email:
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4.
Prairie dogs (Cynomys spp.) have been poisoned throughout this century because of grazing competition with livestock. Recent evidence showed these early claims were exaggerated, but animal control was already entrenched in government policy. As a result, ongoing government subsidized poisoning has reduced prairie dogs to about 2% of their former distribution. The reduction of prairie dogs diminished species diversity in the arid grasslands of North America, including the potential extinction of the black-footed ferret (Mustela nigripes). Cost-benefit analysis revealed that poisoning costs more than any grazing benefits accrued. This analysis did not consider the long-term costs of reversing ecosystem degradation, the intangible value of biological diversity as a public benefit, or the depletion of biotic resources as a loss of actual or potential wealth. The government presently finances the poisoning policy and the preservation of endangered species like the black-footed ferret, two apparently conflicting programs. We, therefore, propose an integrated management plan that considers both interests. We propose that federal monies allocated to the poisoning program be converted into a rebate for ranchers who manage livestock while preserving the prairie dog community. This would redirect funds and personnel already allocated to prairie dog eradication to an incentive for ranchers who manage for livestock and wildlife. Livestock interests and grassland biotic diversity would both benefit.  相似文献   

5.
In the United States, the common interest often is conceived as a by-product of the pluralist, interest-group-driven democratic process. Special interests dominate in many political arenas. Consequently, we have lost the language, vocabulary, and ability to talk about the common interest. The way to reverse this trend is to develop and practice with new tools that allow us to articulate what we mean by the common interest in specific contexts. In this article, we leveraged the literature on procedural, substantive, and pragmatic decision making to illustrate how they work together to demonstrate whether and how the common interest was served in three case studies of Healthy Forests Restoration Act implementation on the Apache-Sitgreaves National Forest in Arizona. In two of the cases we found that the common interest was mostly served, while in the third case it was not. Our results raise questions about the ability of procedural criteria or substantive criteria alone to determine effectiveness in decision making. When evaluated together they provide a more complete understanding of how the common interest is or is not served.
Toddi A. SteelmanEmail:
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6.
We examined the prevalence of residential development that occurs with consideration of the natural features of the site, known as conservation design, within county-level planning jurisdictions across Northern Indiana. Using data from telephone interviews with representatives of planning departments, jurisdictions were ranked based on reported use of conservation design. Three categories of use emerged from the data: no use, use of individual practices associated with conservation design, and integration of multiple conservation design practices. Qualitative data analysis revealed that conservation design practices were not being used widely and, when used, were often used to fulfill stormwater requirements. Statistical analysis, using data from interviews, spatial data sets, and the U.S. Census Bureau, identified several significant positive predictors of the levels of conservation design use including conversion of forest or agricultural land cover to urban uses and education levels in the jurisdiction. Many of the interviewees noted that agricultural land is perceived to meet open space needs within their counties. Given that agricultural land does not fully meet all ecosystem needs, education about the benefits of other types of open space is suggested.
Linda Stalker Prokopy (Corresponding author)Email:
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7.
The National Wildlife Refuge System is perhaps the most important system of federal lands for protecting wildlife in the United States. Only at refuges has wildlife conservation been legislated to have higher priority than either recreational or commercial activities. Presently, private ranchers and farmers graze cattle on 981,954 ha and harvest hay on 12,021 ha at 123 National Wildlife Refuges. US Fish and Wildlife Service policy is to permit these uses primarily when needed to benefit refuge wildlife. To evaluate the success of this policy, I surveyed grassland management practices at the 123 refuges. The survey results indicate that in fiscal year 1980 there were 374,849 animal unit months (AUMs) of cattle grazing, or 41% more than was reported by the Fish and Wildlife Service. According to managers' opinions, 86 species of wildlife are positively affected and 82 are negatively affected by refuge cattle grazing or haying. However, quantitative field studies of the effect of cattle grazing and haying on wildlife coupled with the survey data on how refuge programs are implemented suggest that these activities are impeding the goal of wildlife conservation. Particular management problems uncovered by the survey include overgrazing of riparian habitats, wildlife mortality due to collisions with cattle fences, and mowing of migratory bird habitat during the breeding season. Managers reported that they spend $919,740 administering cattle grazing and haying; thus refuge grazing and haying programs are also expensive. At any single refuge these uses occupy up to 50% of refuge funds and 55% of staff time. In light of these results, prescribed burning may be a better wildlife management option than is either cattle grazing or haying.  相似文献   

8.
In this short essay it is argued that recent criticisms portraying the activist environmental movement as overly pessimistic are valid and that the communication of this pessimism to the public at large has been largely counterproductive to the objectives of environmentalists. It is argued that, in contrast to historic assumptions of a ‘progress paradigm’ that epitomized the widely held optimism of the past, the shock tactics and pessimistic media campaigns employed by the activist environmental movement, and the media that capitalizes upon those campaigns, have contributed to the creation of a figurative hopeless age. The key characterization of the hopeless age is the widely held assumption that the future will be worse than the present and that the lives of future generations will be diminished relative to our own. It is argued that the creation of this social-psychological phenomenon is counterproductive to the aims of the environmental movement and that the restoration of a collective vision and message of hope would be far more productive. Lastly, some reasons for a hopeful outlook are suggested.
Andrew McKinleyEmail: Email:
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9.
The use of voluntary programs targeting resource conservation on private land has become increasingly prevalent in environmental policy. Voluntary programs potentially offer significant benefits over regulatory and market-based approaches. This article examines the factors affecting landowner participation in voluntary forest conservation programs using a combination of parcel-level GIS and remotely sensed data and semi-structured interviews of landowners in Monroe County, Indiana. A logistic regression model is applied to determine the probability of participation based on landowner education, membership in other non-forest voluntary programs, dominant land use activity, parcel size, distance from urban center, land resource portfolios, and forest cover. Both land use activity and the spatial configuration of a landholder’s resource portfolio are found to be statistically significant with important implications for the design and implementation of voluntary programs.
Derek KauneckisEmail:
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10.
This study attempts to apply choice experiments with regard to the residential waste disposal system (RWDS) in Korea by considering various attributes that are related to RWDS. Using data from a survey conducted on 492 households, the empirical analysis yields estimates of the willingness to pay for a clean food-waste collection facility, the collection of small items (such as obsolete mobile phones and add-ons for personal computers), and a more convenient large waste disposal system. The estimation results of multinomial logit models are quite similar to those of nested logit models. The results reveal that residents have preferences for the cleanliness of facilities and the collection of small items. In Korea, residents are required to purchase and attach stickers for the disposal of large items; they want to be able to obtain stickers at not only village offices but also supermarkets. On the other hand, the frequency of waste collection is not a significant factor in the choice of the improved waste management program.
Seung-Hoon YooEmail:
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11.
Sustainability assessment (SA) is a holistic and long-range strategic instrument capable of assisting policy-making in electing, and deciding upon, future development priorities. The outcomes of an SA process become more relevant and strengthened when conducted with multi-stakeholder engagement, which provides for multiple dialogues and perspectives. This was the object of research of the SA team in the context of BioScene (Scenarios for Reconciling Biodiversity Conservation with Declining Agriculture Use in Mountain Areas in Europe), a three-year project (2002–2005) funded by the European Union 5th Framework Program, which aimed to investigate the implications of agricultural restructuring and decline for biodiversity conservation in the mountain areas of Europe, using three distinct methodological streams: the ecological, the socio-economic, and the SA approaches. The SA approach drew on the previous two to assess the importance for biodiversity management of different scenarios of agri-environmental change and rural policy in six countries (France, Greece, Norway, Slovakia, Switzerland, and the United Kingdom), develop causal chains, include stakeholder views, and identify potential contributions for, or conflicts with, sustainability. This article tells how SA was used, what sustainability meant in each study area through different objectives of sustainability considered, discusses the methods used in SA, and the benefits arising. The SA was conducted by a team independent of any study area, who developed and oversaw the application of the SA methodology, assisting national teams, and developing a cross-country understanding of the sustainability of proposed scenarios in the different geographical and social contexts, and their implications for policy-making. Finally, it reflects on the persistent challenges of interdisciplinary research, compounded by multi-cultural teams, and concludes on the BioScene’s lessons for the further development and application of SA.
William R. SheateEmail:
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12.
Woody shrub encroachment severely impacts on the hydrological and erosion response of rangelands and abandoned cultivated lands. These processes have been widely investigated at various spatial scales, using mostly field experimentation. The present study used remote sensing to investigate spatial and temporal patterns of soil erosion and encroachment by a woody shrub species, Pteronia incana, in a catchment in Ngqushwa district, Eastern Cape Province, South Africa between 1998 and 2008. The extreme categories of soil erosion and shrub encroachment were mapped with higher accuracy than the intermediate ones, particularly where lower spatial resolution data were used. The results showed that soil erosion in the worst category increased simultaneously with dense woody shrub encroachment on the hill slopes. This trend is related to the spatial patterning of woody shrub vegetation that increases bare soil patches—leading to runoff connectivity and concentration of overland flow. The major changes in soil erosion and shrub encroachment analysed during the 10-year period took place in the 5–9° slope category and on the concave slope form. Multi-temporal analyses, based on remote sensing, can extend our understanding of the dynamics of soil erosion and woody shrub encroachment. They may help benchmark the processes and assist in upscaling field studies.  相似文献   

13.
Cross-boundary coordination is a tool for ecosystem management whereby landowners voluntarily coordinate management practices toward economic and/or ecological landscape-scale outcomes (e.g., fiber, invasive species control, habitat). Past research indicates that it may be particularly applicable on landscapes that include small forest landholdings. To explore alternatives by which coordination might occur, we conducted seven focus groups with landowners (n = 51) who actively manage their forests in southwest Wisconsin and northeast Iowa. Focus group participants were presented with three hypothetical alternatives to coordinate with their neighbors; landowners could self-organize, work with a natural resource professional (i.e., forester), or work with an organization to complete a cross-boundary practice. In this article, we focus on the latter two alternatives and the role of two social theories—principal-agent and cooperation—in explaining landowners’ evaluations of these alternatives. Key findings are that (1) cross-boundary coordination has the potential to alleviate problems between landowners and resource professionals inherent to their typical working relationship, and (2) social relationships are a major factor contributing to landowners’ willingness to participate. We posit that cross-boundary coordination offers a non-economic incentive for landowners to work together as it may reduce the uncertainty associated with hiring a resource professional. At the same time, professionals can provide a bridging function among landowners who are unacquainted. To achieve these outcomes and expand the adoption of cross-boundary coordination, we suggest four guidelines. First, foster dialogue among landowners toward shared cognition and oversight. Second, match landowners’ practices and objectives such that there are clear benefits to all. Third, develop relationships through low risk activities where possible. Fourth, do not expect on-going commitments.
Mark RickenbachEmail:
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14.
Common decision support tools and a growing body of knowledge about ecological recovery can help inform and guide large state and federal restoration programs affecting thousands of impaired waters. Under the federal Clean Water Act (CWA), waters not meeting state Water Quality Standards due to impairment by pollutants are placed on the CWA Section 303(d) list, scheduled for Total Maximum Daily Load (TMDL) development, and ultimately restored. Tens of thousands of 303(d)-listed waters, many with completed TMDLs, represent a restoration workload of many years. State TMDL scheduling and implementation decisions influence the choice of waters and the sequence of restoration. Strategies that compare these waters’ recovery potential could optimize the gain of ecological resources by restoring promising sites earlier. We explored ways for states to use recovery potential in restoration priority setting with landscape analysis methods, geographic data, and impaired waters monitoring data. From the literature and practice we identified measurable, recovery-relevant ecological, stressor, and social context metrics and developed a restorability screening approach adaptable to widely different environments and program goals. In this paper we describe the indicators, the methodology, and three statewide, recovery-based targeting and prioritization projects. We also call for refining the scientific basis for estimating recovery potential.
Paul ZephEmail:
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15.
Agricultural expansion and deforestation are spatial processes of land transformation that impact on landscape pattern. In peninsular Malaysia, the conversion of forested areas into two major cash crops—rubber and oil palm plantations—has been identified as driving significant environmental change. To date, there has been insufficient literature studying the link between changes in landscape patterns and land-related development policies. Therefore, this paper examines: (i) the links between development policies and changes in land use/land cover and landscape pattern and (ii) the significance and implications of these links for future development policies. The objective is to generate insights on the changing process of land use/land cover and landscape pattern as a functional response to development policies and their consequences for environmental conditions. Over the last century, the development of cash crops has changed the country from one dominated by natural landscapes to one dominated by agricultural landscapes. But the last decade of the century saw urbanization beginning to impact significantly. This process aligned with the establishment of various development policies, from land development for agriculture between the mid 1950s and the 1970s to an emphasis on manufacturing from the 1980s onward. Based on a case study in Selangor, peninsular Malaysia, a model of landscape pattern change is presented. It contains three stages according to the relative importance of rubber (first stage: 1900–1950s), oil palm (second stage: 1960s–1970s), and urban (third stage: 1980s–1990s) development that influenced landscape fragmentation and heterogeneity. The environmental consequences of this change have been depicted through loss of biodiversity, geohazard incidences, and the spread of vector-borne diseases. The spatial ecological information can be useful to development policy formulation, allowing diagnosis of the country’s “health” and sustainability. The final section outlines the usefulness of landscape analysis in the policy-making process to prevent further fragmentation of the landscape and forest loss in Malaysia in the face of rapid economic development.
Adnan A. HezriEmail:
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16.
ABSTRACT: The hydrologic impacts of livestock grazing schemes on selected plant communities and soils at Fort Stanton, New Mexico, were evaluated. Simulated rainfall was applied to 1 m2plots. On a mesa-top, infiltration rates for a grassland livestock exclosure and a pinyon pine-juniper community closely approximated each other and were significantly greater (P = 0.10) than either a moderate continuous or a heavy continuous treatment in a grassland community. Sediment concentration from the heavy continuous treatment was more than twice that of the other treatments. Infiltration rates on the hillside site were highest in a pinyon pine-juniper community receiving short duration grazing. Infiltration for this treatment was found to be significantly higher (P = 0.10) than that of a short duration grazing treatment, but not from a rest rotation grazing treatment on grassland. The short duration grazing treatment on a grassland had the highest sediment concentration, while the rest rotation grazing on a grassland and the short duration pinyon pine-juniper treatments were found to be similar. In the bottomland site, a fertilized and unfertilized treatment showed no significant difference in infiltration or sediment concentration, although twice as many animals were present on the fertilized treatment.  相似文献   

17.
Making Capacity Building Meaningful: A Framework for Strategic Action   总被引:1,自引:0,他引:1  
This paper aims to give practical meaning to ‘capacity building’ through (a) identifying a suite of practical measures, such as mentoring or best practice guidelines, that have been shown to or are considered to build human, social, institutional, and economic capital; (b) placing these measures within a broader systems framework; and (c) exploring stakeholder feedback on specific measures to inform framework implementation. The 29 measures described provide actors, whether government or nongovernment, with a suite of practical investment choices for building capacity. These measures are then clustered into eight groups according to their primary purpose and placed within a systems framework. The framework provides a tool for actors with responsibilities for or an interest in capacity building to inform more holistic and strategic targeting of effort and investment. Stakeholder feedback gathered through surveys and workshops is subsequently reported to further inform implementation of specific measures within the framework’s eight groupings. The framework presented may be built upon through the identification and inclusion of further capacity building measures. The research is conducted within the context of decentralized governance arrangements for natural resource management (NRM), with specific focus on Australia’s recently formalized 56 NRM regions and their community-based governing boards as an informative arena of learning. Application of the framework is explored in the Australian setting through the identification and comparison of measures supported and most preferred by four major stakeholder groups, namely board members, regional NRM organization staff, policy/research interests, and Indigenous interests. The research also examines stakeholder perceptions of capacity issues, and whether these issues are likely to be addressed through implementing their preferred measures.
Lisa RobinsEmail:
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18.
The effects of livestock grazing on selected riparian and stream attributes, water chemistry, and algal biomass were investigated over a two-year period using livestock enclosures and by completing stream surveys in the Cypress Hills grassland plateau, Alberta, Canada. Livestock enclosure experiments, partially replicated in three streams, comprised four treatments: (1) early season livestock grazing (June–August), (2) late season livestock grazing (August–September), (3) all season grazing (June–September), and (4) livestock absent controls. Livestock grazing significantly decreased streambank stability, biomass of riparian vegetation, and the extent to which aquatic vegetation covered the stream channels compared with livestock-absent controls. Water quality comparisons indicated significant differences among the four livestock grazing treatments in Battle and Graburn creeks but not in Nine Mile Creek. In Graburn Creek, the concentration of total phosphorus in the all-season livestock grazing treatment was significantly higher than that in the livestock-absent control, and the early season and late season grazing treatments. Concentrations of soluble reactive phosphorus in the all-season livestock grazing treatment also exceeded that in livestock-absent control. In contrast, differences in water quality variables in the remaining 22 comparisons (i.e., 22 of the total 24 comparisons) were minor even when differences were statistically significant. Effects of livestock grazing on algal biomass were variable, and there was no consistent pattern among creeks. At the watershed scale, spatial variation in algal biomass was related (P < 0.05) with concentrations of NO2 + NO3 and soluble reactive phosphorus in two of the four study creeks. Nutrient diffusing substrata experiments showed that algal communities were either nitrogen-limited or not limited by nutrients, depending on stream and season.  相似文献   

19.
This paper reports an assessment of the current and potential impacts of invasive alien plants on selected ecosystem services in South Africa. We used data on the current and potential future distribution of 56 invasive alien plant species to estimate their impact on four services (surface water runoff, groundwater recharge, livestock production and biodiversity) in five terrestrial biomes. The estimated reductions in surface water runoff as a result of current invasions were >3000 million m3 (about 7% of the national total), most of which is from the fynbos (shrubland) and grassland biomes; the potential reductions would be more than eight times greater if invasive alien plants were to occupy the full extent of their potential range. Impacts on groundwater recharge would be less severe, potentially amounting to approximately 1.5% of the estimated maximum reductions in surface water runoff. Reductions in grazing capacity as a result of current levels of invasion amounted to just over 1% of the potential number of livestock that could be supported. However, future impacts could increase to 71%. A ‘biodiversity intactness index’ (the remaining proportion of pre-modern populations) ranged from 89% to 71% for the five biomes. With the exception of the fynbos biome, current invasions have almost no impact on biodiversity intactness. Under future levels of invasion, however, these intactness values decrease to around 30% for the savanna, fynbos and grassland biomes, but to even lower values (13% and 4%) for the two karoo biomes. Thus, while the current impacts of invasive alien plants are relatively low (with the exception of those on surface water runoff), the future impacts could be very high. While the errors in these estimates are likely to be substantial, the predicted impacts are sufficiently large to suggest that there is serious cause for concern.  相似文献   

20.
A cost-effectiveness analysis was performed to evaluate the competitiveness of seminatural Free Water Surface (FWS) wetlands compared to traditional wastewater-treatment plants. Six scenarios of the service costs of three FWS wetlands and three different wastewater-treatment plants based on active sludge processes were compared. The six scenarios were all equally effective in their wastewater-treatment capacity. The service costs were estimated using real accounting data from an experimental wetland and by means of a market survey. Some assumptions had to be made to perform the analysis. A reference wastewater situation was established to solve the problem of the different levels of dilution that characterize the inflow water of the different systems; the land purchase cost was excluded from the analysis, considering the use of public land as shared social services, and an equal life span for both seminatural and traditional wastewater-treatment plants was set. The results suggest that seminatural systems are competitive with traditional biotechnological systems, with an average service cost improvement of 2.1-fold to 8-fold, according to the specific solution and discount rate. The main improvement factor was the lower maintenance cost of the seminatural systems, due to the self-regulating, low artificial energy inputs and the absence of waste to be disposed. In this work, only the waste-treatment capacity of wetlands was considered as a parameter for the economic competitiveness analysis. Other goods/services and environmental benefits provided by FWS wetlands were not considered.
Daniel FrancoEmail:
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