Although generally accepted as a necessary step to improve water management and planning, integrated water resources management (IWRM) methodology does not provide a clear definition of what should be integrated. The various water-related issues that IWRM might encompass are well documented in the literature, but they are generally addressed separately. Therefore, water management lacks a holistic, systems-based description, with a special emphasis on the interrelations between issues. This article presents such a system model for water management, including a graphical representation and textual descriptions of the various water issues, their components, and their interactions. This model is seen as an aide-memoire and a generic reference, providing background knowledge helping to elicit actual system definitions, in possible combination with other participatory systems approaches. The applicability of the model is demonstrated through its application to two test case studies.
/ Current private and public regulatory systems may not provide an optimal degree of regulation for labels bearing environmental information, and established institutions may detract from efforts to provide for better environmental management. The advent of ISO 14000 offers new opportunities for making eco-labeling a meaningful tool to encourage environmental stewardship. While new federal legislation offers the best vehicle to introduce these standards into US law, the slow pace of the legislative process may recommend an alternative system. Multinational and civic-minded firms may be expected to employ private programs to nurture benevolent environmental management practices until more definitive governmental institutions can be put in place.KEY WORDS: Eco-labels; Environmental labeling; International standards; ISO 14000
For decades, industry has been the main source of pollution in China. Determined to make changes, the mainland Chinese authorities have decided to promote mechanisms that incorporate environmental concerns into the internal management of enterprises. This is manifested in the rapid adoption of the ISO14000 standards, including a significant increase in ISO14001 registrations in China. Thus, this study examined the environmental policy statements of 106 certified facilities in mainland China against a strict interpretation of the mandatory requirements of the ISO 14001:1996 standard and the nonmandatory ISO14004 requirements in order to shed some light on the implementation of environmental management systems in an emerging economic giant. It was decided to analyze the environmental policy statement because such a statement is a core element in the ISO system of environmental management of each facility and there are relatively clear and specific requirements on what an environmental policy statement shall include. An analysis of the contents of the environmental policy statements shows that conformance to the relevant requirements of both the mandatory ISO14001 standard and the nonmandatory ISO14004 standard is far from impressive and that the facilities in our sample seldom went beyond the minimum requirements. By using ISO14001 and ISO14004 conformance scores as the dependent variables, we found that conformity to ISO14001 and overall conformance to ISO14000 series can be explained to some extent by the degree of top management commitment, the experience with informal environmental management systems, and the form of ownership of the facilities.
This study examines the motivations of mainland Chinese facilities in seeking ISO 14001 certification and examines the linkages between these motivations and self-reports of the effectiveness of major environmental management system (EMS) components. In a sample of 128 facilities in Beijing, Shanghai, and Guangzhou, the main drivers for certification were reported to be to ensure regulatory compliance, to enhance the firm's reputation, and to improve environmental performance, in that order. Although motivation to achieve cost reductions were least emphasized, a broad range of motivations appears to be considered in the decision to seek certification to ISO 14001. Regression models linking these motivations to the EMS components suggests that internal motivations have an influence on most EMS components. One interesting exception to this, however, is that no significant relationship was observed between internal motivations and the promulgation of environmental objectives and targets. The relationships associated with external motivations for certification (i.e., those in response to customer and other stakeholder pressures) and EMS components, on the other hand, are weaker and tend to occur earlier in the process cycle. No significant relationships were found between motivations to reduce costs and perceptions of the effectiveness of EMS components. Overall, these findings suggest that ISO 14001, as currently being implemented in mainland China, may have a modestly useful role when used in combination with other policy mechanisms to move the Chinese economy toward more sustainable practices. It is asserted that the ISO standard could provide even greater benefits if Chinese registrars were more proactive in developing EMS in conjunction with even more rigorous third-party audits.
The methodological framework set by standards ISO 14001 and ISO 14004 gives only general principles for environmental aspects assessment, which is regarded as one of the most critical stages of implementing environmental management system. In Estonia, about 100 organizations have been certified to the ISO 14001. Experience obtained from numerous companies has demonstrated that limited transparency and reproducibility of the assessment process serves as a common shortcoming. Despite rather complicated assessment schemes sometimes used, the evaluation procedures have been largely based on subjective judgments because of ill-defined and inadequate assessment criteria. A comparison with some similar studies in other countries indicates a general nature of observed inconsistencies. The diversity of approaches to the aspects' assessment in concept literature and to the related problems has been discussed. The general structure of basic assessment criteria, compatible with environmental impact assessment and environmental risk analysis has also been outlined. Based on this general structure, the article presents a tiered approach to help organize the assessment in a more consistent manner.
The management of large carnivores in multi-use landscapes is always controversial, and managers need to balance a wide range of competing interests. Hunter harvest is often used to limit population size and distribution but is proving to be both controversial and technically challenging. Eurasian lynx (Lynx lynx) are currently managed as a game species in Norway. We describe an adaptive management approach where quota setting is based on an annual census and chart the population development through the period 1996-2008, as management has become significantly more sophisticated and better informed by the increased availability of scientific data. During this period the population has been through a period of high quotas and population decline caused by fragmented management authority and over optimistic estimates of lynx reproduction, followed by a period of recovery due to quota reductions. The modern management regime is placed in the context of shifting policy during the last 160 years, during which management goals have moved from extermination stimulated by bounties, through a short phase of protection, and now to quota-regulated harvest. Much management authority has also been delegated from central to local levels. We conclude that adaptive management has the potential to keep the population within some bounded limits, although there will inevitably be fluctuation.
Brazil's Cuiabá-Santarém (BR-163) Highway provides a valuable example of ways in which decision-making procedures for infrastructure projects in tropical forest areas need to be reformulated in order to guarantee that environmental concerns are properly weighed. BR-163, which is slated to be paved as an export corridor for soybeans via the Amazon River, traverses an area that is largely outside of Brazilian government control. A climate of generalized lawlessness and impunity prevails, and matters related to environment and to land tenure are especially unregulated. Deforestation and illegal logging have accelerated in anticipation of highway paving. Paving would further speed forest loss in the area, as well as stimulate migration of land thieves (grileiros) to other frontiers. An argument is made that the highway should not be reconstructed and paved until after a state of law has been established and it has been independently certified that sufficient governance prevails to secure protected areas and enforce environmental legislation. A waiting period is needed after this is achieved before proceeding with the highway paving. Above all, the logical sequence of steps must be followed, whereby environmental costs are assessed, reported, and weighed prior to making de facto decisions on implementation of infrastructure projects. Deviation from this logical sequence is a common occurrence in many parts of the world, especially in tropical areas.
An important population of the critically endangered pearl mussel Margaritifera margaritifera (Linnaeus, 1758) was surveyed at the edge of its southern distribution (River Paiva, Portugal). Although an earlier study suggested that this population had a very low number of individuals (<500), a narrow distribution, and was mainly comprised by old specimens our data contradict these findings. Our assessment estimated a population with probably more than 5,000 individuals distributed across 80 km of the river length. From the 32 sites surveyed, 19 contained M. margaritifera with higher abundances verified in the middle and upper parts of the river (a maximum of 78 ind. per 100 m of river stretch was recorded). The pearl mussels showed a clear preference for areas near the banks, in shallow water, sandier and gravel sediments, and a high degree of riparian vegetation cover. The population structure was skewed with a very high percentage of large (and old) animals but 3.7 % of the individuals collected were juveniles (<60 mm in length); therefore, this population can be considered functional. Environmental characterization indicated that this river is still in excellent or good condition although some areas showed deterioration due to discharge of domestic effluents. The main conservation requirements of M. margaritifera in the River Paiva include maintaining the water quality (and if possible stopping the discharge of domestic effluents), increasing riparian vegetation cover, removing several weirs to increase connectivity, and increasing trout density.
The historical floods that have occurred since the seventeenth century were collected for a study area in southern Italy. Damages caused by floods, rainfall and the main anthropogenic modifications are discussed all together. The aim was to assess whether the frequency of floods is changing and, if so, whether these changes can be attributed to either rainfall and/or anthropogenic modifications. In 4 % of cases, mainly occurred in past centuries, floods damaged people. Hydraulic works, roads and private buildings were the more frequently damaged elements (25, 18 and 14 % of the cases, respectively). The annual variability of rainfall was discussed using an annual index. Short duration-high intensity rainfalls were characterized considering time series of annual maxima of 1, 3, 6, 12, and 24 h and daily rainfall. The rainfall shows a decreasing trend, in terms of both the annual maximum of short duration and the annual amount. The population has been progressively increasing since the sixteenth century, except during the years following the catastrophic 1908 earthquake. The rate of population growth has been very high since the second half of the twentieth century; the urbanized areas greatly increased, especially following the second half of the twentieth century. At the same time, the trend of damaging floods has been increasing, especially since the seventies. The analysis indicates that, despite a rainfall trend favourable towards a reduction in flood occurrence, floods damage has not decreased. This seems to be mainly the effect of mismanagement of land use modifications.
/ To understand the total impact of humans on the carbon cycle, themodeling and quantifying of the transfer of carbon from terrestrial pools tothe atmosphere is becoming more critical. Using previously published data,this research sought to assess the change in carbon pools caused by humans inthe Lower Fraser Basin (LFB) in British Columbia, Canada, since 1827 anddefine the long-term, regional contribution of carbon to the atmosphere. Theresults indicate that there has been a transfer of 270 Mt of carbon frombiomass pools in the LFB to other pools, primarily the atmosphere. The majorlosses of biomass carbon have been from logged forests (42%), wetlands(14%), and soils (43%). Approximately 48% of the forestbiomass, almost 20% of the carbon of the LFB, lies within old-growthforest, which covers only 19% of the study area. Landfills are nowbecoming a major sink of carbon, containing 5% of the biomass carbonin the LFB, while biomass carbon in buildings, urban vegetation, mammals, andagriculture is negligible. Approximately 26% of logged forest biomasswould still be in a terrestrial biomass pool, leaving 238 Mt of carbon thathas been released to the atmosphere. On an area basis, this is 29 times theaverage global emissions of carbon, providing an indication of the pastcontributions of developed countries such as Canada to global warming andpossible contributions from further clearing of rainforest in both tropicaland temperate regions.KEY WORDS: Carbon pools; Global warming; Carbon release to atmosphere;Greenhouse effect
/ European settlement began in the Lower Fraser Basin (LFB) inwestern British Columbia in 1827 and has impacted the basin ecosystem in anumber of ways, especially affecting the vegetation. Using previouslypublished data, air photos, and other historical material for the area,estimates of land cover were made for the years prior to 1827 and for 1930and 1990. The area of coniferous forest changed from 71% prior to 1827to 50% in 1930 to 54% in 1990. However, prior to 1827, only27% of the forest would have been immature (<120 years old), while40% would have been immature in 1930 and 73% of the forest wasimmature in 1990. The amount of wetland area decreased from 10% to1% of the study area while urban and agricultural area increased to26% of the study area by 1990. The changes in land cover have hadadverse effects on soil, water, and air quality; aquatic life; and plant andanimal populations. Estimates of changes in net primary production andorganic soil carbon suggest a decline over the past 170 years, although thelatter rate of decrease has slowed since 1930. As human populations in theLower Fraser Basin continue to increase, the quality of air, water, and soilwill continue to decline unless measures are taken.KEY WORDS: Human impact; Land cover; Net primary productivity; Organiccarbon in soil
The progressive degradation of aquatic ecosystems and ecohydrological role of rivers is one of the most important global environmental issues. The loss of the ability of rivers to self-purify waters due to the disturbances of river continuity cause a lack of biological life in parts of rivers or even in an entire river. The appearance of alien species in degraded aquatic environments is an increasingly common phenomenon and constitutes one of the threats to biodiversity. The aim of the study was to evaluate the possible impact of alien species Potamopyrgus antipodarum (Gray, 1843) and Gammarus tigrinus (Sexton, 1939) on native invertebrates as well as the influence of environmental factors on the occurrence benthos fauna including also alien species. The study conducted in industrial area, in the River Ruda (Poland), showed that at the sites at which the occurrence of the two alien species was observed, the density of native benthos and diversity decreased significantly. CCA analysis showed that non-native species occurred in fast water velocity and that their presence was associated with high values of conductivity, hardness, and a high chloride content. The arrival of new species from other geographical areas is one of the factors that influences the species balance in native aquatic fauna. The number of alien species in freshwater ecosystems probably will increase in the future as new aliens are moved outside of their native ranges.
/ An index of upland wildlife habitat was developed to investigate patterns and changes in habitat over time, using four years (1920, 1940, 1964, 1987) and the state of Illinois as an example. The index was composed of two subdivisions that described, at the county level, the quantity of wildlife habitat and a third subdivision that described farming disturbances that impacted the quality of the habitat. Data came from the US Census of Agriculture. The first subdivision that reflected quantity of habitat was called the wildlife habitat subdivision and was the sum of percentage woodland on farms, percentage farmland in nonrow crops, and percentage farmland in set-aside programs. The second subdivision that reflected the quantity of habitat was termed the soil-related features subdivision and was the sum of the percentage of farmland that was not highly erodible, the percentage of farmland in soil-protecting crops, and the percentage of farmland in conservation tillage. The third subdivision, reflecting the quality of the habitat, was the farming disturbance subdivision and was the sum of the percentage of grazing and the percentage of land on which fertilizers, pesticides, and herbicides were applied. Overall, major decreases occurred between 1920 and 1987 in the subdivisions reflecting the quantity of wildlife habitat and a major increase occurred in the subdivision associated with farming disturbance, reflecting the intensification of agriculture in the state. However, there was variability throughout the state, with some counties being more favorable to wildlife (as measured by the subdivisions) than others. Most of the changes within the state for the subdivisions reflecting quantity of upland wildlife habitat occurred during 1940 while changes in the farming disturbance subdivision (reflecting habitat quality) occurred in 1964. By 1987, the western and southern parts of Illinois were the most favorable for wildlife as reflected in all three subdivisions. Upland wildlife harvest indices were related to the subdivisions in 1964 and 1987, when harvest indices were available. Cottontail and northern bobwhite harvests were higher in counties with higher amounts of the wildlife habitat subdivision in both years. Cottontail harvest was also higher in counties with lower levels of the farming disturbance subdivision in 1964 and higher levels of soil-related features subdivision in 1987. Indices at the county level have the potential to be used in a multiscale analysis to investigate the impact of policy changes on large-scale areas of the Midwest and to develop regional perspectives of the impacts of agriculture on upland wildlife and their habitats.KEY WORDS: Upland wildlife; Habitat; Agriculture; Illinois
A large number of studies have documented 20th century climate variability and change at the global, hemispheric, and regional levels. However, understanding the implications of climate change for environmental management necessitates information at the level of the ecosystem. Historical monitoring data from the Chesapeake Bay estuary were used to identify temporal patterns of estuarine temperature anomalies in the surface (</=1 m) and subsurface (>/=15 m) between 1949 and 2002. Data indicated a trend in surface and subsurface warming of +0.16 degrees C and +0.21 degrees C per decade, respectively, driven by warming during winter and spring. These trends suggest warming of the estuary since the mid-20th century of approximately 0.8-1.1 degrees C. Estuarine temperatures correlated well with other independent data records for sea surface and surface air temperatures in the region and to a lesser extent, the northern hemisphere. Gross long-term temperature variability in the estuary was consistent with North Atlantic climate variability associated with the prolonged positive North Atlantic Oscillation/Arctic Oscillation and increased anthropogenic radiative forcing, although localized environmental drivers likely are important as well. A simple spatial analysis revealed strong seasonal latitudinal and longitudinal gradients in estuarine temperature as well as a north-south gradient in long-term temperature trends. Continued warming of the estuary will have important implications for ecosystem structure and function as well as attempts to manage existing challenges such as eutrophication and benthic hypoxia. However, such management efforts must be cognizant of the effects of various climate and nonclimate drivers of environmental variability and change operating over different spatial and temporal scales.
Approximately 37% of forestlands in the conterminous United States are publicly owned; they represent a substantial area of potential carbon sequestration in US forests and in forest products. However, large areas of public forestlands traditionally have been less intensively inventoried than privately owned forests. Thus, less information is available about their role as carbon sinks. We present estimates of carbon budgets on public forestlands of the 48 conterminous states, along with a discussion of the assumptions necessary to make such estimates. The forest carbon budget simulation model, FORCARB2, makes estimates for US forests primarily based on inventory data. We discuss methods to develop consistent carbon budget estimates from inventory data at varying levels of detail. Total carbon stored on public forestlands in the conterminous US increased from 16.3 Gt in 1953 to the present total of 19.5 Gt, while area increased from 87.1 million hactares to 92.1 million hactares. At the same time the proportion of carbon on public forestlands relative to all forests increased from 35% to 37%. Projections for the next 40 years depend on scenarios of management influences on growth and harvest.
Oyster beds are disappearing worldwide through a combination of over-harvesting, diseases, and salinity alterations in the coastal zone. Sensitivity of oysters to variable discharge and salinity is particularly acute in small sub-tropical estuaries subject to regulated freshwater releases. South Florida has sub-tropical estuaries where watershed flood control sometimes results in excessive freshwater inflow to estuaries during the wet season (May-Oct) and reduced discharge and increased salinities in the dry season (Nov-Apr). The potential to reserve freshwater accumulated during the wet season could offer the capacity to regulate freshwater at different temporal scales, thus optimizing salinity conditions for estuarine biota. The goal of this study was to use simulation modeling to explore the effects of freshwater inflows and salinity on adult oyster survival in the Caloosahatchee River Estuary (CRE) in southwest Florida. Water managers derived three different freshwater inflow scenarios for the CRE based on historical and modified watershed attributes for the time period of 1965-2000. Three different salinity time series were generated from the inflow scenarios at each of three sites in the lower CRE and used to conduct nine different oyster simulations. Overall, the predicted densities of adult oysters in the upstream site were 3-4 times greater in seasons that experienced reduced freshwater inflow (e.g., increased salinity) with oyster density in the lower estuary much less influenced by the inflows. Potential storage of freshwater reduced the frequency of extreme flows in the wet season and helped to maintain minimum inflow in the dry season near the estuarine mouth. Analyses of inflows indicated that discharges ranging from 0 to 1,500 cfs could promote favorable salinities of 10-25 in the lower CRE depending on wet versus dry season climatic conditions. This range of inflows is similar to that derived in other studies of the CRE and emphasizes the value of simulation models to help prescribe freshwater releases which benefit estuarine biota.
The Barataria Basin, Louisiana, USA, is an extensive wetland and coastal estuary system of great economic and intrinsic value. Although high rates of wetland loss along the coastal margin of the Barataria Basin have been well documented, little information exists on whether freshwater wetlands in the upper basin have changed. Our objectives were to quantify land-cover change in the upper basin over 20 years from 1972-1992 and to determine land-cover transition rates among land-cover types. Using 80-m resolution Landsat MSS data from the North American Landscape Characterization (NALC) data archive, we classified images from three time steps (1972, 1985, 1992) into six land-cover types: agriculture, urban, bottomland hardwood forest, swamp forest, freshwater marsh, and open water. Significant changes in land cover occurred within the upper Barataria Basin over the study period. Urban land increased from 8% to 17% of the total upper basin area, primarily due to conversions from agricultural land, and to a lesser degree, bottomland forest. Swamp forest increased from 30% to 41%, associated with conversions from bottomland hardwood forest and freshwater marsh. Overall, bottomland forest decreased 38% and total wetland area increased 21%. Within the upper Barataria, increases in total wetland area may be due to land subsidence. Based on our results, if present trends in the reduction of bottomland forest land cover were to continue, the upper Barataria Basin may have no bottomland hardwood forests left by the year 2025, as it is subjected to multiple stressors both in the higher elevations (from urbanization) and lower elevations (most likely from land subsidence). These results suggest that changes in the upper freshwater portions of coastal estuaries can be large and quite different from patterns observed in the more saline coastal margins.
Quantifying the spatial and temporal dynamics of carbon stocks in terrestrial ecosystems and carbon fluxes between the terrestrial biosphere and the atmosphere is critical to our understanding of regional patterns of carbon budgets. Here we use the General Ensemble biogeochemical Modeling System to simulate the terrestrial ecosystem carbon dynamics in the Jinsha watershed of China's upper Yangtze basin from 1975 to 2000, based on unique combinations of spatial and temporal dynamics of major driving forces, such as climate, soil properties, nitrogen deposition, and land use and land cover changes. Our analysis demonstrates that the Jinsha watershed ecosystems acted as a carbon sink during the period of 1975-2000, with an average rate of 0.36 Mg/ha/yr, primarily resulting from regional climate variation and local land use and land cover change. Vegetation biomass accumulation accounted for 90.6% of the sink, while soil organic carbon loss before 1992 led to a lower net gain of carbon in the watershed, and after that soils became a small sink. Ecosystem carbon sink/source patterns showed a high degree of spatial heterogeneity. Carbon sinks were associated with forest areas without disturbances, whereas carbon sources were primarily caused by stand-replacing disturbances. It is critical to adequately represent the detailed fast-changing dynamics of land use activities in regional biogeochemical models to determine the spatial and temporal evolution of regional carbon sink/source patterns.
It is generally believed that forest cover in North Korea has undergone a substantial decrease since 1980, while in South Korea, forest cover has remained relatively static during that same period of time. The United Nations Food and Agriculture Organization (FAO) Forest Resources Assessments-based on the reported forest inventories from North and South Korea-suggest a major forest cover decrease in North Korea, but only a slight decrease in South Korea during the last 30 years. In this study, we seek to check and validate those assessments by comparing them to independently derived forest cover maps compiled for three time intervals between 1990 and 2010, as well as to provide a spatially explicit view of forest cover change in the Korean Peninsula since the 1990s. We extracted tree cover data for the Korean Peninsula from existing global datasets derived from satellite imagery. Our estimates, while qualitatively supporting the FAO results, show that North Korea has lost a large number of densely forested areas, and thus in this sense has suffered heavier forest loss than the FAO assessment suggests. Given the limited time interval studied in our assessment, the overall forest loss from North Korea during the whole span of time since 1980 may have been even heavier than in our estimate. For South Korea, our results indicate that the forest cover has remained relatively stable at the national level, but that important variability in forest cover evolution exists at the regional level: While the northern and western provinces show an overall decrease in forested areas, large areas in the southeastern part of the country have increased their forest cover.
What factors explain stakeholders' perceptions of scientists in environmental politics? Questionnaire data are used to examine stakeholders' views of scientific experts in the context of Lake Tahoe environmental policy from 1984 to 2001. Stakeholders' perceptions of scientists have remained the same over time - despite a shift from adversarial to collaborative policymaking and after decades of mounting scientific evidence showing water quality declines. On average, stakeholders perceive scientists with limited influence on Lake Tahoe environmental policy and view them with mixed levels of skepticism. Stakeholders' evaluation of scientists is best explained by their beliefs about development versus the environment. Stakeholders in favor of more land development express distrust of scientists and negatively evaluate university researchers and consultants. Stakeholders in favor of environmental protection are more likely to trust scientists and positively evaluate university researchers and consultants.
On the basis of the cross-section and time-series data of the Lower Mekong Basin (LMB)--including large sections of Thailand, Lao PDR, Vietnam, and Cambodia, we find little evidence in support of the environmental Kuznets curve (EKC) hypothesis. Instead, our regressions support the general views that water pollution had been positively related to income level and that, as a result of the end of the Cold War era, it had been significantly reduced in the 1990s vis-à-vis the 1980s. In most circumstances, water resources were more seriously polluted in the transnational border areas than in the other areas. Specifically, the estimated coefficients on the political boundary dummies show that political influence on transnational water pollution was more significant in areas near "the international border along which the river runs" (denoted by BORDER2) than in places near "the international border across which the river runs" (denoted by BORDER1). The estimated coefficients on the ASEAN dummy present some information about the positive role of the Association for Southeast Asian Nations (ASEAN) membership in the reduction of transnational water pollution. Finally, the country-specific dummies are found to present conflicting information about the transnational differences of water pollution, although Thailand is found to have the least water pollution in the LMB.
This research investigates urban sprawl in the Greater Toronto Area (GTA) between 1985 and 2005 and the nature of the resulting landscape fragmentation, particularly with regard to the Oak Ridges Moraine (ORM), an ecologically important area for the region. Six scenes of Landsat TM imagery were acquired in summer of 1985, 1995, and 2005. These images and their texture measures were classified into eight land cover classes with very satisfactory final overall accuracies (93-95 %). Analysis of the classifications indicated that urban areas grew by 20 % between 1985 and 1995 and by 15 % between 1995 and 2005. Landscape fragmentation due to spatio-temporal land cover changes was evaluated using urban compactness indicators and landscape metrics, and results from the latter were used to draw conclusions about probable environmental impact. The indicator results showed that urban proportions increased in nearly all areas outside of the metropolitan center, including on portions of the ORM. The landscape metrics reveal that low density urban areas increased significantly in the GTA between 1985 and 2005, mainly at the expense of agricultural land. The metric results indicate increased vulnerability and exposure to adverse effects for natural and semi-natural land cover through greater contrast and lowered connectivity. The degree of urban perimeter increased around most environmentally significant areas in the region. Changes like these negatively impact species and the regional water supply in the GTA. Further investigation into specific environmental impacts of urban expansion in the region and which areas on the ORM are most at risk is recommended.
Twenty-three Section 404 permits in central Pennsylvania (covering a wetland age range of 1-14 years) were examined to determine the type of mitigation wetland permitted, how the sites were built, and what success criteria were used for evaluation. Most permits allowed for mitigation out-of-kind, either vegetatively or through hydrogeomorphic class. The mitigation process has resulted in a shift from impacted wetlands dominated by woody species to less vegetated mitigation wetlands, a trend that appears to be occurring nationwide. An estimate of the percent cover of emergent vegetation was the only success criterion specified in the majority of permits. About 60% of the mitigation wetlands were judged as meeting their originally defined success criteria, some after more than 10 years. The permit process appears to have resulted in a net gain of almost 0.05 ha of wetlands per mitigation project. However, due to the replacement of emergent, scrub-shrub, and forested wetlands with open water ponds or uplands, mitigation practices probably led to a net loss of vegetated wetlands.
Market-based approaches to environmental regulation (such as tradable permits or transferable quotas) are frequently offered as innovative solutions to many environmental problems. Globally, one of the most well-established forms of this approach is individual transferable quotas (or ITQs) in fisheries management. Within the natural resource management community, there is considerable debate over the effects ITQs have on the fishing industry and fisher behavior although this approach is not well-established in the United States. The previously imposed moratorium on ITQs in the United States has expired and the 2006 reauthorization of the Magnuson-Stevens Act explicitly provides for limited access privileges (LAPs). A variety of fishers, regulators, and conservation organizations are enthusiastically seeking to introduce ITQ management. With debate over whether and how ITQs should be used in American fisheries reinvigorated, it is timely to examine the evidence on the social and economic effects of ITQs in other nations' fisheries. After briefly summarizing the debate on ITQs, we examine the case of New Zealand, one of the earliest and longest-lived ITQ-based fisheries regimes. We use multiple data sources and methods to analyze the extent to which industry consolidation and aggregation has occurred, including surveys of industry participants, expert interviews, reviews of academic reports and analyses, analysis of trade publications, and direct analysis of quota ownership patterns. This analysis shows a more complex outcome than recent debates in the ITQ literature would predict. These findings suggest that policy makers considering ITQs can learn from the experiences of other countries related to key issues such as quota allocation, aggregation limits, transferability, cost recovery, and resource sustainability when designing ITQ and other LAP systems. It is also important to explicitly identify economic and social objectives and then carefully design ITQ regimes to meet these objectives.
Electric power generating plants that use coal were among the key targets of Title IV of the 1990 Clean Air Act. Under the first phase of the act, 110 coal-fired electric power plants were required to reduce their sulfur dioxide emissions by 1995 and nitrogen oxide emissions by 1996. Phase 2 of the act requires even greater reduction of sulfur dioxide emissions by 2000 and nitrogen oxide emissions by 2008. This study examines whether the 107 targeted plants (three plants went off-line) have achieved the desired sulfur dioxide and nitrogen oxide emission levels.
The analysis of sulfur dioxide is based on data from 1990, 1995, and 1999. The findings show that although sulfur oxide increased by 3% from 1995 to 1999, it decreased by 45% over the 1990–1999 period at the firm level for the targeted firms. The findings also indicate that the overall reduction in sulfur dioxide was achieved by utilizing low sulfur coal and by purchasing emission allowances. So far as nitrogen oxides are concerned, there has been a reduction of 14% over the 1990–1999 period, of which 7% was achieved during the 1995–1999 period. An evaluation of emissions at the plant level indicates that several plants do not meet the emissions level for sulfur dioxide or nitrogen oxides.
These results provide a mixed scorecard for reduction in emissions both for sulfur dioxide and nitrogen oxides. Even though there is reduction in the emissions on an overall basis at the firm level, several plants that have not been able to reduce emissions deserve special attention to meet the goals of the act in reducing emissions.
Through interpreting Landsat TM images, this study analyzes the spatial distribution of rural settlements in China in 2000. It calculates rural residential land percentage for every 1-km(2) cell. The entire country is divided into 33 regions to investigate the spatio-temporal dynamic patterns of rural residential land during the 1990s. According to the remote sensing survey, the rural residential land increased by 7.88 x 10(5) ha in the 1990s. The increment of rural residential land was 0.55 million ha in 1990-1995 and 0.23 million ha in 1995-2000. In 1990-1995, rural residential land increased dramatically in the eastern regions such as the Yangtze River Delta, Pearl River Delta, and North China Plain, accounting for 80.80% of the national growth; the expansion in the western regions was much more moderate. In 1995-2000, the expansion of rural residential land in eastern regions slowed, accounting for only 58.54% of the increase at the national level, whereas the expansion in the western regions accelerated. Rapid rural residential development resulted from increasing home construction and the limited control on rural land. The great regional disparity reflected the regional economic development and land-use policy change. Our finding shows that nearly 60% of the rural residential area came from cropland.
Vernal pools are vulnerable to loss through development and agricultural and forestry practices owing to their isolation from open water bodies and their small size. Some vernal pool-dependent species are already listed in New England as Endangered, Threatened, or Species of Special Concern. Vernal pool creation is becoming more common in compensatory mitigation as open water ponds, in general, may be easier to create than wooded wetlands. However, research on vernal pool creation is limited. A recent National Research Council study (2001) cites vernal pools as "challenging to recreate." We reviewed documentation on 15 vernal pool creation projects in New England that were required by federal regulatory action. Our purpose was to determine whether vernal pool creation for compensatory mitigation in New England replaced key vernal pool functions by assessing project goals and documentation (including mitigation plans, pool design criteria, monitoring protocols, and performance standards). Our results indicate that creation attempts often fail to replicate lost pool functions. Pool design specifications are often based on conjecture rather than on reference wetlands or created pools that function successfully. Project monitoring lacks consistency and reliability, and record keeping by regulatory agencies is inadequate. Strengthening of protection of isolated wetlands in general, and standardization across all aspects of vernal pool creation, is needed to ensure success and to promote conservation of the long-term landscape functions of vernal pools.
Genetic differences in the Posidonia oceanica meadow of Monterosso al Mare (NW Mediterranean, Marine Protected Areas (MPAs) “Cinque Terre”) were compared in three stations, at an increasing distance from a source of impact (beach nourishment) in the recent decade. Random amplified polymorphic DNA analysis showed a higher genetic variability (>20 %) in the area directly subjected to the stress, increasing with time. Clone integration, confirmed by phenotypic analysis, showed increases both in shoot density and leaf length connected to genetic differences observed in DNA fingerprints of new shoots. Analysis of molecular variance (AMOVA) showed 45 % individual differences within populations and 54 % among the populations. The fixation index (F
ST = 0.54), of the genetic differentiation, showed a marked difference between the populations at different temporal scales. Over a decade AMOVA indicated genetic variations from 28 % (1998) to 54 % (2009). These results make it clear that in the P. oceanica population examined the environment had, in ten years, selected those clones which were more resistant to the anthropogenic impact, despite being subjected to the effects of the resuspension of fine sediments. These findings could help to explain both the survival of the regressed Mediterranean P. oceanica meadows in areas subjected to moderate impacts and the extreme variability in success of revegetation experiments. Management of the ecological disturbance here described indicates also the timescale in population response to stress and its increased resilience in MPAs.
Protected areas are designated to protect species and other features known to be present at the time of designation, but over time the information about the presence of protected species may change and this should call for a continued review of conservation objectives. Published scientific literature is one of the possible information sources that would trigger a review of conservation objectives. We studied how published data on new discoveries of protected animal species were taken into account by the nature conservation authorities in updating species lists of Natura 2000 sites in the European Union, which are the basis for conservation planning at the site-level. Over the period studied (2000-2011) only 40 % of published new protected species records were recognized by the authorities. The two main reasons for this seem to be a reliance on other sources of information by authorities and the difficulty in finding relevant information in scientific papers. The latter is because published faunistic information is very fragmented among different journals, and often insufficient in details. We recommend better cooperation between authors, publishers, and nature conservation authorities in terms of information presentation, publishing policy, and a regular review of published information.
The Natura 2000 network was established across the European Union's (EU) Member States with the aim to conserve biodiversity, while ensuring the sustainability of human activities. However, to what kind and to what extent Natura 2000 sites are subject to human activities and how this varies across Member States remains unspecified. Here, we analyzed 111,269 human activity records from 14,727 protected sites in 20 Member States. The frequency of occurrence of activities differs among countries, with more than 86 % of all sites being subjected to agriculture or forestry. Activities like hunting, fishing, urbanization, transportation, and tourism are more frequently recorded in south European sites than in northern or eastern ones. The observed variations indicate that Natura 2000 networks are highly heterogeneous among EU Member States. Our analysis highlights the importance of agriculture in European landscapes and indicates possible targets for policy interventions at national, European, or "sub-European" level. The strong human presence in the Natura 2000 network throughout Member States, shows that conservation initiatives could succeed only by combining social and ecological sustainability and by ensuring the integration of policies affecting biodiversity.
In spite of widespread support from most member countries' societies for European Union policy, including support for the sustainable development idea, in many EU countries the levels of acceptance of new environmental protection programmes have been and, in particular in new member states, still are considerably low. The experience of the countries which were the first to implement union directives show that they cannot be effectively applied without widespread public participation. The goal of this study was, using the example of Poland, to assess public acceptance of the expansion of nature conservation in the context of sustainable development principles and to discover whether existing nature governance should be modified when establishing new protected areas. The increase in protected areas in Poland has become a hotbed of numerous conflicts. In spite of the generally favourable attitudes to nature which Polish people generally have, Natura 2000 is perceived as an unnecessary additional conservation tool. Both local authorities and communities residing in the Natura areas think that the programme is a hindrance, rather than a help in the economic development of municipalities or regions, as was initially supposed. This lack of acceptance results from many factors, mainly social, historic and economic. The implications of these findings for current approach to the nature governance in Poland are discussed.
The Sacramento-San Joaquin Delta, the landward reach of the San Francisco Estuary, provides habitat for threatened delta smelt, endangered winter-run Chinook salmon, and other species of concern. It is also the location of huge freshwater diversion facilities that entrain large numbers of fish. Reducing the entrainment of listed fishes into these facilities has required curtailment of pumping, reducing the reliability of water deliveries. We reviewed the first 5 years (2001-2005) of the Environmental Water Account (EWA), a program instituted to resolve conflicts between protecting listed fishes and providing a reliable water supply. The EWA provided fishery agencies with control over 0.2-0.4 km(3) of water to be used for fish protection at no cost to users of exported water, and fish agencies guaranteed no disruption of water supply for fish protection. The EWA was successful in reducing uncertainty in water supply; however, its contribution to the recovery of listed fishes was unclear. We estimated the effectiveness of the EWA to be modest, increasing the survival of winter-run Chinook salmon by 0-6% (dependent on prescreen mortality), adult delta smelt by 0-1%, and juvenile delta smelt by 2-4%. Allocating EWA water for a single life stage of one species could provide larger gains in survival. An optimally allocated EWA of equal size to the median of the first 5 years could increase abundance of juvenile delta smelt up to 7% in the springs of dry years. If the EWA is to become a long-term program, estimates of efficacy should be refined. If the program is to be held accountable for quantitative increases in fish populations, it will be necessary to integrate scientific, possibly experimental, approaches.
The increase in damage due to natural disasters is directly related to the number of people who live and work in hazardous areas and continuously accumulate assets. Therefore, land use planning authorities have to manage effectively the establishment and development of settlements in flood-prone areas in order to avoid the further increase of vulnerable assets. Germany faced major destruction during the flood in August 2002 in the Elbe and Danube catchments, and many changes have been suggested in the existing German water and planning regulations. This article presents some findings of a “Lessons Learned” study that was carried out in the aftermath of the flood and discusses the following topics: 1) the establishment of comprehensive hazard maps and flood protection concepts, 2) the harmonization of regulations of flood protection at the federal level, 3) the communication of the flood hazard and awareness strategies, and 4) how damage potential can be minimized through measures of area precaution such as resettlement and risk-adapted land use. Although attempts towards a coordinated and harmonized creation of flood hazard maps and concepts have been made, there is still no uniform strategy at all planning levels and for all states (Lae
nder) of the Federal Republic of Germany. The development and communication of possible mitigation strategies for “unthinkable extreme events” beyond the common safety level of a 100-year flood are needed. In order to establish a sustainable and integrated flood risk management, interdisciplinary and catchment-based approaches are needed.
Cetacean-focused tourism in Taiwan has grown rapidly since 1997. This development, measured in terms of both number of tour boats and visitors, has resulted in many resource management challenges stemming from the absence of regulation and scientific data. To fill this void in empirical evidence, we used 464 sighting records from 2002 to 2005 to model the impact of cetacean-focused tourism. Cox proportional hazard analysis indicated cetacean avoidance responses to cetacean watching boats were strongly associated with pod size, mother-calf pairs, and cetacean-vessel distances. Mother-calf pairs abandoned their avoidance tactic by 55% compared to noncalf groups when tour boats approached. Second, the hazard ratio of abundance was 0.996, suggesting that the odds of encountering avoidance responses by the cetaceans decreased by 42% for every 100-member increase in the cetacean pod size. Last, distances maintained by boats from the cetaceans was positively related to avoidance responses (i.e., less avoidance behavior with closer interaction). Based on our findings, we have the following recommendations: (a) limit vessels from approaching mothers with calves, (b) limit vessels from approaching small groups of cetaceans, (c) reduced avoidance behavior to boat traffic may be a red flag for potential long-term disturbance, and (d) apply the "precautionary principle" based on the best scientific information available in cetacean-based tourism in Taiwan. These recommendations will help contribute to the sustainable development of cetacean-focused tourism in Taiwan.
This study empirically estimates the multiple benefits of a subsidy policy that would offer payments to farmers in return for the adoption of conservation tillage, and compares the outcomes of alternative targeting designs for such a policy. The least-cost incentive payment policy schemes are simulated for the State of Iowa by using the data for roughly 12,000 National Resource Inventory (NRI) points. We use an economic conservation tillage adoption model to evaluate the costs of adoption and a physical process simulation model (EPIC) to estimate the environmental benefits due to adoption at each of the NRI points. Two targeting options are considered. We assess the costs and environmental consequences of a practice-based policy instrument (which maximizes the acres of land in conservation tillage, regardless of its level of environmental benefits) and contrast it to a performance-based instrument (which yields the highest amount of environmental benefits per dollar spent). Carbon sequestration in agricultural soils, reduction of soil erosion by wind and water, and the reduction in nitrogen runoff are considered as possible targets for the performance-based instruments. We find that the practice-based instrument provides high proportions of the four benefits relative to the policies that target the benefits directly, especially at the higher policy budget levels. Similarly, we estimate that targeting one of the four benefits individually provides high percentages of the other benefits as compared with the amounts of the benefits obtainable if they were targeted directly.
The purpose of this forum is to respond to a rebuttal submitted by Julian et al., Environ Manag 55:1-5, 2015 where they outlined their overall disagreement with the data preparation, methods, and interpretation of results presented in Gabriel et al. (Environ Manag 53:583-593, 2014). Here, we provide background information on the research premise presented in Gabriel et al. (Environ Manag 53:583-593, 2014) and provide a defense for this work using five themes. In spite of what Julian et al. perceive as limitations in the sampling methods and analytical tools used for this work, the relationships found between fish total mercury and surface water sulfate concentrations in Gabriel et al. (Environ Manag 53:583-593, 2014) are comparable to relationships between pore water methylmercury (MeHg) and pore water sulfate found in past studies indicating that sulfate is important to MeHg production and bioaccumulation in the Everglades. Julian et al. state "…there is no way to justify any ecosystem-wide sulfur strategy as a management approach to reduce mercury risk in the (Everglades) as suggested by Gabriel et al. (Environ Manag 53:583-593, 2014), Corrales et al. (Sci Tot Environ 409:2156-2162, 2011) and Orem et al. (Rev Environ Sci Technol 41 (S1):249-288, 2011)." We disagree, and having stated why sulfate input reduction to the Everglades may be the most effective means of reducing mercury in Everglades fish, it is important that research on sulfur and mercury biogeochemistry continues. If further studies support the relationship between sulfate loading reduction and MeHg reduction, sulfur mass balance studies should commence to (1) better quantify agricultural and connate seawater sulfate inputs and (2) define opportunities to reduce sulfate inputs to the Everglades ecosystem.
Based on previously published studies of elemental cycling in Everglades soils, we projected how soil biogeochemistry, specifically carbon, nitrogen, phosphorus, sulfur, and mercury might respond to climate change scenarios projected for 2060 by the South Florida Water Management Model. Water budgets and stage hydrographs from this model with future scenarios of a 10 % increased or decreased rainfall, a 1.5 °C rise in temperature and associated increase in evapotranspiration (ET) and a 0.5 m rise in sea level were used to predict resulting effects on soil biogeochemistry. Precipitation is a much stronger driver of soil biogeochemical processes than temperature, because of links among water cover, redox conditions, and organic carbon accumulation in soils. Under the 10 % reduced rainfall scenario, large portions of the Everglades will experience dry down, organic soil oxidation, and shifts in soil redox that may dramatically alter biogeochemical processes. Lowering organic soil surface elevation may make portions of the Everglades more vulnerable to sea level rise. The 10 % increased rainfall scenario, while potentially increasing phosphorus, sulfur, and mercury loading to the ecosystem, would maintain organic soil integrity and redox conditions conducive to normal wetland biogeochemical element cycling. Effects of increased ET will be similar to those of decreased precipitation. Temperature increases would have the effect of increasing microbial processes driving biogeochemical element cycling, but the effect would be much less than that of precipitation. The combined effects of decreased rainfall and increased ET suggest catastrophic losses in carbon- and organic-associated elements throughout the peat-based Everglades.
Rising sea levels and temperature will be dominant drivers of coastal Everglades' foundation communities (i.e., mangrove forests, seagrass/macroalgae, and coral reefs) by 2060 based on a climate change scenario of +1.5 °C temperature, +1.5 foot (46 cm) in sea level, ±10 % in precipitation and 490 ppm CO2. Current mangrove forest soil elevation change in South Florida ranges from 0.9 to 2.5 mm year(-1) and would have to increase twofold to fourfold in order to accommodate a 2060 sea level rise rate. No evidence is available to indicate that coastal mangroves from South Florida and the wider Caribbean can keep pace with a rapid rate of sea level rise. Thus, particles and nutrients from destabilized coastlines could be mobilized and impact benthic habitats of southern Florida. Uncertainties in regional geomorphology and coastal current changes under higher sea levels make this prediction tentative without further research. The 2060 higher temperature scenario would compromise Florida's coral reefs that are already degraded. We suggest that a new paradigm is needed for resource management under climate change that manages coastlines for resilience to marine transgression and promotes active ecosystem management. In the case of the Everglades, greater freshwater flows could maximize mangrove peat accumulation, stabilize coastlines, and limit saltwater intrusion, while specific coral species may require propagation. Further, we suggest that regional climate drivers and oceanographic processes be incorporated into Everglades and South Florida management plans, as they are likely to impact coastal ecosystems, interior freshwater wetlands and urban coastlines over the next few decades.
During the last two decades, the State of Connecticut has restored tidal flow to many impounded salt marshes. One of the first of these and the one most extensively studied is Impoundment One in the Barn Island Wildlife Management Area in Stonington, Connecticut. In 1990, twelve years after the re-establishment of tidal flooding, the density of the marsh snail Melampus bidentatus, the numerically dominant macroinvertebrate of the high marsh, in Impoundment One was about half that in reference marshes below the breached impoundment dike. By 1999 the densities of Melampus above and below the dike were not significantly different, but the shell-free biomass was greater above the dike as a result of the somewhat larger number and size of the snails there. Twenty-one years after the renewal of tidal flooding, three marsh macroinvertebrates (the amphipods Orchestia grillus and Uhlorchestia spartinophila and the mussel Geukensia demissa) were significantly less abundant in the previously impounded marsh than in the reference marshes, whereas another amphipod (Gammarus palustris) was more abundant above the breached dike where conditions appeared to be somewhat wetter. In 1991 the fish assemblage in a mosquito-control ditch in Impoundment One was similar to that in a ditch below the breached dike; however, the common mummichog Fundulus heteroclitus appeared to be less abundant in the restoring marsh. By 1999 the number of mummichogs caught in ditches was significantly greater in Impoundment One than in the reference marsh, but the numbers of mummichogs trapped along the tidal creek were comparable above and below the dike. The results obtained in this study and those of other restoring marshes at Barn Island indicate the full recovery of certain animal populations following the reintroduction of tidal flow to impounded marshes may require up to two or more decades. Furthermore, not only do different species recover at different rates on a single marsh, but the time required for the recovery of a particular species may vary widely from marsh to marsh, often independently of other species.
Brazil's BR-319 Highway linked Manaus, in the state of Amazonas, to Porto Velho, Rondônia, until it became impassable in 1988. Now it is proposed for reconstruction and paving, which would facilitate migration from the "Arc of Deforestation" in the southern part of the Amazon region to new frontiers farther north. The purpose of the highway, which is to facilitate transport to São Paulo of products from factories in the Manaus Free Trade Zone, would be better served by sending the containers by ship to the port of Santos. The lack of a land connection to Manaus currently represents a significant barrier to migration to central and northern Amazonia. Discourse regarding the highway systematically overestimates the highway's benefits and underestimates its impacts. A variety of changes would be needed prior to paving the highway if these potential impacts are to be attenuated. These include zoning, reserve creation, and increased governance in various forms, including deforestation licensing and control programs. More fundamental changes are also needed, especially the abandonment of the long-standing tradition in Brazil of granting squatters' rights to those who invade public land. Organizing Amazonian occupation in such a way that road construction and improvement cease to lead to explosive and uncontrolled deforestation should be a prerequisite for approval of the BR-319 and other road projects for which major impacts are expected. These projects could provide the impetus that is needed to achieve the transition away from appropriation of public land by both small squatters and by grileiros (large-scale illegal claimants). A delay in reconstructing the highway is advisable until appropriate changes can be effected.
As early as the passage of the 1972 Federal Water Pollution Control Act the U.S. government has sought to protect the nation's water resources through regulatory tools. While there has been a large amount of research on wetlands and wetland mitigation, very little is known about the impact of Section 404 permitting on water quantity. This research examines the impact of Section 404 permit types on peak annual streamflow in Coastal Texas from 1996 to 2003. Results of cross-sectional time-series regression analyses indicate that all four permit types have positive and significant effects on peak streamflow. These effects also vary by permit type, with Individual permits having the highest per-permit impact on peak annual flow.
Past tree colonization dynamics of a powerline-right-of-way (ROW) corridor in the Haut-Saint-Laurent region of Quebec was studied based on the present age distribution of its tree populations. This colonization study spans 20 years, from 1977 (ROW clearance) to 1996. The sampled quadrats were classified into six vegetation types. Tree colonization dynamics were interpreted in each type, and three distinct patterns were identified. (1) Communities adapted to acidic conditions were heavily colonized by Acer rubrum, at least for the last 12 years. (2) Communities adapted to mesic or to hydric conditions were more intensely colonized in the period 1985–1987 than in the following 9 years; this past success in tree colonization may have been caused by herbicide treatments, which could have facilitated tree establishment by damaging the herbaceous and shrub vegetation. (3) Cattail, vine-raspberry, and reed-dominated communities contained few tree individuals, with almost all trees establishing between 1979 and 1990; those three vegetation types appear as the most resistant to tree invasion in the ROW studied.
This study supports the need for an integrated approach in ROW vegetation management, in which the selection of vegetation treatment methods would depend on the tree colonization dynamics in each vegetation type. Minimizing disturbances inflicted on ROW herbaceous and shrub covers should be the central strategy because disturbances jeopardize natural resistance to future tree invasion, except in communities adapted to acidic conditions where the existing vegetation does not prevent invasion by A. rubrum. Many trees are surviving the successive cutting operations by producing new sprouts each time, particularly in communities adapted to mesic and hydric conditions. In these cases, mechanical cutting should be replaced by a one-time stump-killing operation, to avoid repeated and unsuccessful treatments of the same individuals over time.
This study presents a meta-analysis of a collective dataset describing the succession from abandoned fields to semi-natural grassland and heathland vegetation over the past century. The study objectives were to develop a method for statistical discrimination between abandoned fields and semi-natural habitats and to analyze the probability that an abandoned field had developed into a semi-natural habitat. A statistical classification model was developed, based on lists of vascular plants from 2059 plots from Danish semi-natural grasslands and heathlands, and abandoned fields of varying age. This model was shown to discriminate effectively between abandoned fields and semi-natural habitats, and it was found to be potentially useful for the detection of abandoned fields approaching semi-natural vegetation. We suggest that the model may help clarify restoration targets and assess biological condition in formerly cultivated areas. Statistical modeling revealed that succession age, period of abandonment and succession trajectory had significant effects on the probability that abandoned fields reached the semi-natural phase. Our study indicates that restoration projects targeting grassland and heathland should take local species pools and soil fertility into account.
Plant-soil interactions are known to influence a wide range of ecosystem-level functions. Moreover, the recovery of these functions is of importance for the successful restoration of soils that have been degraded through intensive and/or inappropriate land use. Here, we assessed the effect of planting treatments commonly used to accelerate rates of grassland restoration, namely introduction of different legume species Medicago sativa, Astragalus adsurgens, Melilotus suaveolens, on the recovery of soil microbial communities and carbon and nitrogen contents in abandoned fields of the Loess Plateau, China. The results showed effects were species-specific, and either positive, neutral or negative depending on the measure and time-scale. All legumes increased basal respiration and metabolic quotient and had a positive effect on activity and functional diversity of the soil microbial community, measured using Biolog EcoPlate. However, soil under Astragalus adsurgens had the highest activity and functional diversity relative to the other treatments. Soil carbon and nitrogen content and microbial biomass were effectively restored in 3-5 years by introducing Medicago sativa and Astragalus adsurgens into early abandoned fields. Soil carbon and nitrogen content were retarded in 3-5 years and microbial biomass was retarded in the fifth year by introducing Melilotus suaveolens. Overall, the restoration practices of planting legumes can significantly affect soil carbon and nitrogen contents, and the biomass, activity, and functional diversity of soil microbial community. Therefore, we propose certain legume species could be used to accelerate ecological restoration of degraded soils, hence assist in the protection and preservation of the environment.
Poor vegetation cover is generally considered to be a major factor causing soil erosion on the Loess Plateau in China. It has been argued that tree planting restoration is ineffective, and natural re-vegetation is an alternative ecological solution for restoring abandoned cropland and controlling soil erosion. The aims of this study were to investigate the characteristics of soil seed banks and to assess the natural restoration potential of abandoned cropland in the hilly-gullied Loess Plateau. The soil seed bank was identified by the germination method with the soil samples, which were collected at four sampling times (April, August, and October 2005 and August 2006) from 12 plots abandoned 3-30 years prior to sampling. The seed bank densities of all of the samples in the 0-10 cm soil layer varied from 1,067 ± 225 to 14,967 ± 1,606 seeds m(-2). Fifty-one species (24 annual and 27 perennial species) belonging to 18 families were identified, and 39% of these species belonged to the families Compositae and Gramineae. The pioneer species Artemisia scoparia dominated the seed bank, with an average seed density of 3,722 seeds m(-2), and accounted for 74.4% of the seeds in the bank. The local dominant species (such as Lespedeza davurica, Artemisia gmelinii, Bothriochloa ischaemun and Stipa bungeana) of the later succession stages also existed at densities varying from 17 to 1, 383 seeds m(-2). The combination of soil seed bank characteristics, reproductive traits of the species, the specific landscape conditions indicates that the potential to restoring the abandoned croplands in the hilly-gullied Loess Plateau via natural re-vegetation could be substantial.
The lack of a particular use associated with abandoned farmland provides real opportunities with respect to the various land-use pressures occurring in productive territories. These environments remain generally poorly known and, because of this, require in-depth studies on the feasibility of management options, on biological as well as social grounds. This study, based on research on the biophysical potential and the perceptions by the owners of abandoned farmlands, analyzes the feasibility of silvicultural management options to improve forestry potential. Using a questionnaire, we surveyed abandoned farmland owners on different aspects of the status of their abandoned farmland in order to determine their willingness toward the management of these private lands. The land owners were also asked to express their interests and their constraints toward various types of interventions, with an emphasis on silvicultural work. The data were analyzed using multivariate methods to establish relationships between the questionnaire data and the characteristics of the land owners (socioeconomic profile and value system toward the environment). The results show that, in general, abandoned farmland is an unwanted space, is generally little used, is poorly known, and has little importance in the plans of its owners. We have found three types of owner profiles; the owners with a farmer's profile are those who are the most interested in managing their abandoned farmland, whether for agriculture or silviculture. The desire to improve abandoned farmland seems less important to owners with an ecocentric profile (high awareness of the environment) and to older owners. Finally, by associating the type of abandoned farmland owned and the characteristics of the owners, it is possible to propose different management options that reconcile the wishes of the owners as well as the biophysical potential of their abandoned farmland.
Coal mine reclamation projects are very expensive and require coordination of local and federal agencies to identify resources for the most economic way of reclaiming mined land. Location of resources for mine reclamation is a spatial problem. This article presents a methodology that allows the combination of spatial data on resources for the coal mine reclamation and uses GIS analysis to develop a priority list of potential mine reclamation sites within contiguous United States using the method of extrapolation. The extrapolation method in this study was based on the Bark Camp reclamation project. The mine reclamation project at Bark Camp, Pennsylvania, USA, provided an example of the beneficial use of fly ash and dredged material to reclaim 402,600 sq mi of a mine abandoned in the 1980s. Railroads provided transportation of dredged material and fly ash to the site. Therefore, four spatial elements contributed to the reclamation project at Bark Camp: dredged material, abandoned mines, fly ash sources, and railroads. Using spatial distribution of these data in the contiguous United States, it was possible to utilize GIS analysis to prioritize areas where reclamation projects similar to Bark Camp are feasible. GIS analysis identified unique occurrences of all four spatial elements used in the Bark Camp case for each 1 km of the United States territory within 20, 40, 60, 80, and 100 km radii from abandoned mines. The results showed the number of abandoned mines for each state and identified their locations. The federal or state governments can use these results in mine reclamation planning.
Agricultural landscapes illustrate the impact of human actions on physical settings, and differential human pressures cause these landscapes to change with time. Our study explored changes in the terraced landscapes of Nisyros Island, Greece, focusing on the socioeconomic aspects during two time periods using field data, cadastral research, local documents, and published literature, as well as surveys of the islanders. Population increases during the late 19th to early 20th centuries marked a significant escalation of terrace and dry stone wall construction, which facilitated cultivation on 58.4% of the island. By the mid-20th century, the economic collapse of agricultural activities and consequent emigration caused the abandonment of cultivated land and traditional management practices, dramatically reducing farm and field numbers. Terrace abandonment continued in recent decades, with increased livestock grazing becoming the main land management tool; as a result, both farm and pasture sizes increased. Neglect and changing land use has led to deterioration and destruction of many terraces on the island. We discuss the socioeconomic and political backgrounds responsible for the land-use change before World War II (annexation of Nisyros Island by the Ottoman Empire, Italy, and Greece; overseas migration opportunities; and world transportation changes) and after the war (social changes in peasant societies; worldwide changes in agricultural production practices). The adverse landscape changes documented for Nisyros Island appear to be inevitable for modern Mediterranean rural societies, including those on other islands in this region. The island's unique terraced landscapes may qualify Nisyros to become an archive or repository of old agricultural management techniques to be used by future generations and a living resource for sustainable management.
Monitoring of contaminant accumulation in fish has been conducted in East Fork Poplar Creek (EFPC) in Oak Ridge, Tennessee since 1985. Bioaccumulation trends are examined over a twenty year period coinciding with major pollution abatement actions by a Department of Energy facility at the stream's headwaters. Although EFPC is enriched in many contaminants relative to other local streams, only polychlorinated biphenyls (PCBs) and mercury (Hg) were found to accumulate in the edible portions of fish to levels of human health concern. Mercury concentrations in redbreast sunfish were found to vary with season of collection, sex and size of individual fish. Over the course of the monitoring, waterborne Hg concentrations were reduced >80%; however, this did not translate into a comparable decrease in Hg bioaccumulation at most sites. Mercury bioaccumulation in fish did respond to decreased inputs in the industrialized headwater reach, but paradoxically increased in the lowermost reach of EFPC. As a result, the downstream pattern of Hg concentration in fish changed from one resembling dilution of a headwater point source in the 1980s to a uniform distribution in the 2000s. The reason for this remains unknown, but is hypothesized to involve changes in the chemical form and reactivity of waterborne Hg associated with the removal of residual chlorine and the addition of suspended particulates to the streamflow. PCB concentrations in fish varied greatly from year-to-year, but always exhibited a pronounced downstream decrease, and appeared to respond to management practices that limited episodic inputs from legacy sources within the facility.
This paper provides an introduction to a long-term biological monitoring program and the Environmental Management special issue titled Long-term Biological Monitoring of an Impaired Stream: Implications for Environmental Management. The Biological Monitoring and Abatement Program, or BMAP, was implemented to assess biological impairment downstream of U.S. Department of Energy (DOE) facilities in Oak Ridge, Tennessee, beginning in 1985. Several of the unique aspects of the program include its long-term consistent sampling, a focus on evaluating the effectiveness of specific facility abatement and remedial actions, and the use of quantitative sampling protocols using a multidisciplinary approach. This paper describes the need and importance of long-term watershed-based biological monitoring strategies, in particular for addressing long-term stewardship goals at DOE sites, and provides a summary of the BMAP's objectives, spatial and temporal extent, and overall focus. The primary components of the biological monitoring program for East Fork Poplar Creek in Oak Ridge, Tennessee are introduced, as are the additional 9 papers in this Environmental Management special issue.