Assessing Riparian Conservation Land Management Practice Impacts on Gully Erosion in Iowa

Well-established perennial vegetation in riparian areas of agricultural lands can stabilize the end points of gullies and reduce their overall erosion. The objective of this study was to investigate the impacts of riparian land management on gully erosion. A field survey documented the number of gullies and cattle access points in riparian forest buffers, grass filters, annual row-cropped fields, pastures in which the cattle were fenced out of the stream, and continuously, rotationally and intensive rotationally grazed pastures in three regions of Iowa. Gully lengths, depths and severely eroding bank areas were measured. Gullies exhibited few significant differences among riparian management practices. The most significant differences were exhibited between conservation and agricultural management practices, an indication that conservation practices could reduce gully erosion. Changes in pasture management from continuous to rotational or intensive rotational grazing showed no reductions in gully erosion. It is important to recognize that more significant differences among riparian management practices were not exhibited because the conservation and alternative grazing practices had recently been established. As gully formation is more impacted by upland than riparian management, gully stabilization might require additional upland conservation practices. The existence of numerous cattle access points in pastures where cattle have full access to the stream also indicates that these could be substantial sources of sediment for streams. Finally, the gully banks were less important sediment contributors to streams than the streambanks. The severely eroding bank areas in streams were six times greater than those in the gullies in the monitored reaches.     

Adoption Potential of Conservation Agriculture Practices in Sub-Saharan Africa: Results from Five Case Studies

Despite the reported benefits of conservation agriculture (CA), its wider up-scaling in Sub-Saharan Africa (SSA) has remained fairly limited. This paper shows how a newly developed qualitative expert assessment approach for CA adoption (QAToCA) was applied to determine its adoption potential in SSA. CA adoption potential is not a predictor of observed adoption rates. Instead, our aim was to systematically check relevant factors that may be influencing its adoption. QAToCA delivers an assessment of how suitable conditions “and thus the likelihood for CA adoption” are. Results show that the high CA adoption potentials exhibited by the Malawi and Zambia case relate mostly to positive institutional factors. On the other hand, the low adoption potential of the Zimbabwe case, in spite of observed higher estimates, is attributed mainly to unstable and less secured market conditions for CA. In the case of Southern Burkina Faso, the potential for CA adoption is determined to be high, and this assessment deviates from lower observed figures. This is attributed mainly to strong competition of CA and livestock for residues in this region. Lastly, the high adoption potential found in Northern Burkina Faso is explained mainly by the fact that farmers here have no alternative other than to adopt the locally adapted CA system—Zaï farming. Results of this assessment should help promoters of CA in the given regions to reflect on their activities and to eventually adjust or redesign them based on a more explicit understanding of where problems and opportunities are found.     

Biodiversity Conservation and Resource Tenure Regimes: A Case Study from Northeast Cambodia

The management of tropical protected areas is a contentious issue in resource management and often leads to an unproductive polarization of viewpoints supporting either protectionist or sustainable development paradigms. This paper argues for a context-driven approach whereby effective management requires inputs from both paradigms in different situations. A key element of context is understanding long-practiced resource tenures and their ability to meet future conservation and livelihood goals. Different types of tenure arrangements are often required for different resources. This approach is illustrated by analysis of Virachey National Park in NE Cambodia. This park encompasses part of the ancestral territory of ethnic Brao people, who rely upon swidden agriculture, fish, terrestrial wildlife, and various nontimber forest products (NTFPs) for their livelihoods. These people have developed a mix of resource tenure regimes to promote sustainable use and to maximize local benefits. In the face of contemporary pressures, some of these traditional approaches are effective, while others are not. The paper suggests avenues for building on long-established management practices of the Brao to achieve park management goals while enhancing the welfare of the Brao people. A mix of private ownership, common property management, and central government involvement may be required to maximize benefits to local people and ensure long-term protection of biodiversity.     

Trends in Vegetation Degradation in Relation to Land Tenure, Rainfall, and Population Changes in Peddie District, Eastern Cape, South Africa

Spatial and temporal variations in vegetation are examined in relation to land tenure, population increase, and rainfall variation in a part of Peddie district, Eastern Cape. Sequential aerial photographs between 1938 and 1988 are analyzed to determine trends in vegetation and population change in three different land-tenure units. The areal extent at each date of four distinct vegetation categories is determined using PC ARC/INFO GIS. Long-term annual rainfall trends for the area are analyzed and juxtaposed with vegetation changes. Extensive ground-truthing exercises are carried out to verify the present condition of vegetation condition in terms of cover and species composition. Differences in land-tenure systems are discerned as the dominant factor controlling variations in vegetation degradation. The study also reveals that neither population changes nor rainfall variations can explain the observed trends in vegetation degradation. Earlier injudicious land-use practices, sustained since the turn of the last century, may provide plausible explanations for the trends and present status of vegetation degradation in the area.     

Corn-Based Ethanol Production and Environmental Quality: A Case of Iowa and the Conservation Reserve Program

Growing demand for corn due to the expansion of ethanol has increased concerns that environmentally sensitive lands retired from agricultural production and enrolled into the Conservation Reserve Program (CRP) will be cropped again. Iowa produces more ethanol than any other state in the United States, and it also produces the most corn. Thus, an examination of the impacts of higher crop prices on CRP land in Iowa can give insight into what we might expect nationally in the years ahead if crop prices remain high. We construct CRP land supply curves for various corn prices and then estimate the environmental impacts of cropping CRP land through the Environmental Policy Integrated Climate (EPIC) model. EPIC provides edge-of-field estimates of soil erosion, nutrient loss, and carbon sequestration. We find that incremental impacts increase dramatically as higher corn prices bring into production more and more environmentally fragile land. Maintaining current levels of environmental quality will require substantially higher spending levels. Even allowing for the cost savings that would accrue as CRP land leaves the program, a change in targeting strategies will likely be required to ensure that the most sensitive land does not leave the program.     

Adaptive Targeting: Engaging Farmers to Improve Targeting and Adoption of Agricultural Conservation Practices

Targeting of agricultural conservation practices to cost‐effective locations has long been of interest to watershed managers, yet its implementation cannot succeed without meaningful engagement of agricultural producers who are decision makers on the lands they farm. In this study, we engaged 14 west‐central Indiana producers and landowners in an adaptive targeting experiment. Interviews carried out prior to targeting provided rich spatial information on existing conservation practices as well as producers' preferences for future conservation projects. We targeted six of the most accepted conservation practices using the Soil and Water Assessment Tool and spatial optimization using a genetic algorithm approach. Fairly optimal conservation scenarios were possible with even the most limiting constraints of farmer‐accepted practices. We presented in follow‐up interviews a total of 176 conservation practice recommendations on 103 farm fields to 10 farmers whose lands were targeted for conservation. Primary findings indicated producers were interested in the project, were open to hearing recommendations about their lands, and expressed a high likelihood of adopting 35% of targeted recommendations. Farmers generally viewed the interview process and presentation of results quite favorably, and the interviews were found to build trust and make the targeting process more acceptable to them.     

Social Approval of the Community Assessment Model for Odor Dispersal: Results from a Citizen Survey

Odors emitted from US Midwest hog production facilities present farmers, residents, and state regulatory agencies with a set of complex challenges. To predict odor exposure from multiple swine production sources simultaneously, and to determine siting recommendations for proposed new or enlarged hog facilities, researchers at Iowa State University designed the community assessment model for odor dispersion (CAM). A three-county citizen survey conducted in Iowa examined the level of hypothetical social acceptance of the modeling process, and level of trust in CAM results. While 69 % of respondents approved of modeling as a way to determine the most socially appropriate location for production sites, only 35 % would trust the results if potential odor exposure from a new facility were proposed to be built near their home. We analyzed approval of the CAM model, and level of trust, across a number of demographic, attitudinal, and belief factors regarding environmental quality and the hog industry. Overall, trust in CAM was uneven and varied across respondents. Those residents who would not trust CAM tended to be more concerned with environmental quality and less inclined to believe that the hog industry is critically important economically. Those who would not trust CAM results also had significantly more direct experience with odors. Findings point to predominantly positive, yet equivocal acceptance of CAM results among the citizenry, which is not unexpected given conflict typical of siting decisions in industry and waste disposal arenas. Recommendations are offered regarding the interaction of trust, beliefs and attitudes and the utility of CAM.     

An Assessment of Land Conservation Patterns in Maine Based on Spatial Analysis of Ecological and Socioeconomic Indicators

Given the nature of modern conservation acquisitions, which often result from gifts and opportunistic purchases of full or partial property rights, there is a risk that the resulting mosaic of conserved resources may not represent a coherent set of public values and benefits. With different public and private entities engaged in land conservation, one would further expect that each organization would apply separate goals and criteria to the selection and acquisition of its conservation portfolio. This set of circumstances raises an important question: what is the aggregate outcome of this land conservation process? Retrospective assessments provide a means of reviewing cumulative historical decisions and elucidating lessons for improving future conservation strategies. This study used GIS-based spatial analysis to examine the relationships of private and public conservation lands in Maine to a variety of landscape metrics in order to determine the degree to which these lands represent core ecological and socioeconomic values that are meaningful to a wide cross-section of citizens. Results revealed that the gains of past conservation efforts in Maine are counter-balanced to some extent by apparent gaps in the existing fabric of conservation holdings. Conservation lands capture a representative sample of diverse habitat, provide a large measure of protection for multiple conservation values and indicators, and offer an unusual mix of outdoor recreational opportunities for residents and visitors alike. Yet, the majority of parcels are relatively small and isolated, and thus do not provide contiguous habitat blocks that offset ongoing processes of landscape fragmentation. Furthermore, the majority of area associated with many of the ecological metrics examined in this report is located outside the boundaries of current conservation holdings. The under-represented metrics identified in this investigation can be viewed as potential targets for new strategic conservation initiatives.     

Evaluation of nitrate nitrogen fluxes from a tile-drained watershed in central Iowa

Nitrate N fluxes from tile-drained watersheds have been implicated in water quality studies of the Mississippi River basin, but actual NO3-N loads from small watersheds during long periods are poorly documented. We evaluated discharge and NO3-N fluxes passing the outlet of an Iowa watershed (5134 ha) and two of its tile-drained subbasins (493 and 863 ha) from mid-1992 through 2000. The cumulative NO3-N load from the catchment was 168 kg ha(-1), and 176 and 229 kg ha(-1) from the subbasins. The outlet had greater total discharge (1831 mm) and smaller flow-weighted mean NO3-N concentration (9.2 mg L(-1)) than the subbasins, while the larger subbasin had greater discharge (1712 vs. 1559 mm) and mean NO3-N concentration (13.4 vs. 11.3 mg L(-1)) than the smaller subbasin. Concentrations exceeding 10 mg L(-1) were common, but least frequent at the outlet. Nitrate N was generally not diluted by large flows, except during 1993 flooding. The outlet showed smaller NO3-N concentrations at low flows. Relationships between discharge and NO3-N flux showed log-log slopes near 1.0 for the subbasins, and 1.2 for the outlet, considering autocorrelation and measurement-error effects. We estimated denitrification of subbasin NO3-N fluxes in a hypothetical wetland using published data. Assuming that temperature and NO3-N supply could limit denitrification, then about 20% of the NO3-N would have been denitrified by a wetland constructed to meet USDA-approved criteria. The low efficiency results from the seasonal timing and NO3-N content of large flows. Therefore, agricultural and wetland best management practices (BMPs) are needed to achieve water quality goals in tile-drained watersheds.     

Adoption of sustainable agriculture practices: Evidence from a semi-arid region of Ethiopia

In the wake of the resource constraints for external farm inputs faced by farmers in developing countries, sustainable agriculture practices that rely on renewable local or farm resources present desirable options for enhancing agriculture productivity. In this study, plot-level data from the semi-arid region of Ethiopia, Tigray are used to investigate the factors influencing farmers' decisions to adopt agriculture practices, with a particular focus on conservation tillage, compost and chemical fertilizer. A trivariate probit model is used to analyze the determinants of adoption of these practices. In addition, stochastic dominance analysis is used to compare the productivity impacts of compost with that of chemical fertilizer based on a six-year cross-sectional farm-level dataset. Our results indicate heterogeneity with regard to the factors that influence adoption decisions of the three practices and the importance of both plot and household characteristics on influencing adoption decisions. In particular, we found that household endowments and access to information, among other factors, impact the choice of sustainable farming practices significantly. Furthermore, the use of stochastic dominance analysis supported the contention that sustainable farming practices enhance productivity. They even proved to be superior to the use of chemical fertilizers — justifying the need to investigate factors that influence adoption of these practices and to use this knowledge to formulate policies that encourage adoption.     

Conflicting Frames about Ownership and Land Use Drive Wildfire Ignitions in a Protected Conservation Area

The creation of protected conservation areas may result in protracted conflicts between stakeholders. In this study we examine the drivers of anthropogenic wildfire ignitions in the National Park of “los Alerces” (NPA) in Patagonia, Argentina. The NPA was established in 1937 to protect the native “andino-patagónico” forests from wildfires as well as preserving its scenic beauty and native flora and fauna. At the time of its creation state authorities prohibited all extractive human activities in the “intangible”—fully protected—“National Park” section, while other regulated extractive and ecotourism activities were allowed to continue in the “Natural Reserve” section in an effort to accommodate the historical entitlements of the displaced populations of “pobladores” (settlers) that had been living in the NPA for over a century. Here we interviewed the main stakeholder groups—“pobladores”, forest rangers and administrators, ecolodge owners and angler club members—to identify the drivers of wildfire ignitions in the park. Wildfires have been singled out by state authorities as the main threat to the NPA though considerable scientific uncertainty exists regarding their complex ecological effects. This study argues, based on the human and biophysical system data collected, that two conflicting cultural frames exist within the NPA that provide the necessary backdrop for understanding the drivers of wildfire ignitions. In turn, these findings raise puzzling dilemmas for the main theoretical approaches that have been used to inform and design conflict management strategies in protected conservation areas.     

Conservation Covenants on Private Land: Issues with Measuring and Achieving Biodiversity Outcomes in Australia

Conservation covenants and easements have become essential tools to secure biodiversity outcomes on private land, and to assist in meeting international protection targets. In Australia, the number and spatial area of conservation covenants has grown significantly in the past decade. Yet there has been little research or detailed policy analysis of conservation covenanting in Australia. We sought to determine how conservation covenanting agencies were measuring the biodiversity conservation outcomes achieved on covenanted properties, and factors inhibiting or contributing to measuring these outcomes. In addition, we also investigated the drivers and constraints associated with actually delivering the biodiversity outcomes, drawing on detailed input from covenanting programs. Although all conservation covenanting programs had the broad aim of maintaining or improving biodiversity in their covenants in the long term, the specific stated objectives of conservation covenanting programs varied. Programs undertook monitoring and evaluation in different ways and at different spatial and temporal scales. Thus, it was difficult to determine the extent Australian conservation covenanting agencies were measuring the biodiversity conservation outcomes achieved on covenanted properties on a national scale. Lack of time available to covenantors to undertake management was one of the biggest impediments to achieving biodiversity conservation outcomes. A lack of financial resources and human capital to monitor, knowing what to monitor, inconsistent monitoring methodologies, a lack of benchmark data, and length of time to achieve outcomes were all considered potential barriers to monitoring the biodiversity conservation outcomes of conservation covenants.     

Containing Urban Sprawl: Trends in Land Use and Spatial Planning in the Metropolitan Region of Barcelona

In recent decades, there has been considerable debate in the Metropolitan Region of Barcelona regarding the role of spatial planning in influencing general land-use trends. There is a widespread belief amongst geographers, environmentalists, planners and some politicians that spatial planning of the metropolitan region has not been particularly successful in reducing urban pressures on rural areas. The aim of this study is to explore the apparent links between urban sprawl, spatial planning and changing land use in the rural-urban fringe of Barcelona. The paper demonstrates that the main impacts of sprawl have been concentrated in agricultural areas, and that the planning system has not been capable of containing urban growth.     

Conflict and Coalitions: An Examination of Outdoor Recreation Magazines

We examined whether value differences between various recreation interest/activity groups are created and sustained by the textual information presented to their readers in magazines. Using a two-stage qualitative approach, our research sought to explore the exact nature of the dialogue in the magazines. We sought detailed, intimate information on a selected number of magazines to assess how the popular press socially constructs knowledge about recreation groups, and we sought to better understand how various recreation group members assign meaning to their activities and interpret the interests of other groups. Findings revealed limited negativity of activity users towards one another; most of the conflict found in the text of the articles in recreational magazines was characterized as macrodispositional. Accordingly, in the articles most of the antipathy was directed towards government because of stricter regulation of activity or towards commercial consumers whose exploitation of resources is perceived to threaten groups' activities. Moreover, such conflict crosscuts various groups whose issues and concerns are often similar. Since environmental battles are no longer any one group's issue, many have coalesced and engaged in conflict with lawmakers and commercial consumers. It is clear that the recreational magazines do play a role in shaping readers' attitudes.     

An Overview of Nitrogen Cycling in a Semiarid Savanna: Some Implications for Management and Conservation in a Large African Park

Nitrogen (N) is a major control on primary productivity and hence on the productivity and diversity of secondary producers and consumers. As such, ecosystem structure and function cannot be understood without a comprehensive understanding of N cycling and dynamics. This overview describes the factors that govern N distribution and dynamics and the consequences that variable N dynamics have for structure, function and thresholds of potential concern (TPCs) for management of a semiarid southern African savanna. We focus on the Kruger National Park (KNP), a relatively intact savanna, noted for its wide array of animal and plant species and a prized tourist destination. KNP’s large size ensures integrity of most ecosystem processes and much can be learned about drivers of ecosystem structure and function using this park as a baseline. Our overview shows that large scale variability in substrates exists, but do not necessarily have predictable consequences for N cycling. The impact of major drivers such as fire is complex; at a landscape scale little differences in stocks and cycling were found, though at a smaller scale changes in woody cover can lead to concomitant changes in total N. Contrasting impacts of browsers and grazers on N turnover has been recorded. Due to the complexity of this ecosystem, we conclude that it will be complicated to draw up TPCs for most transformations and pools involved with the N cycle. However, we highlight in which cases the development of TPCs will be possible.     

Conservation Considerations for a Management Measure: An Integrated Approach to Hare Rearing and Release

Wildlife managers are challenged with the task of deciding whether a management measure is appropriate or not, and furthermore they have to convince others about the merits of their decision. Population decline of some hare species (genus Lepus) has resulted in their Red Listing and conservation measures are being undertaken. Release or restocking is a frequent measure in some countries, and thousands of hares are released annually, mainly for hunting purposes. These hares can be obtained by either intensive or extensive rearing or translocation of the wild animals. Each method entails difficulties and different survival rates in the wild. Survival rates in the wild are low for hares intensively reared in cages but are higher for hares reared extensively in enclosures and wild translocated hares. The benefits of the hare release practice are significantly lower than the action’s implementation cost. Hare releases have not increased significantly the wild hare population or the hunting harvest in areas where the practice has been applied. The risk of genetic and evolutionary degradation and pathogen transmission is possible in wild populations. The need for wise management of this practice is evident and the term ‘Permitted Transferring Units’ should be introduced to denote regions where hares should not be transferred for rearing and release.     

采油作业区节能减排探索与实践

H作业区经过对节能减排中问题的总结,实施了哈得四联合站放空气回收轻烃外输、哈得一联合站二段气回收、污水闭路循环回收利用、淡化水流程优化等节能减排工程,促进了节能减排,减少了碳排放,实现了清洁生产,取得了较好的经济效益和环境效益。