The influence of use-related,environmental, and managerial factors on soil loss from recreational trails

Recreational uses of unsurfaced trails inevitably result in their degradation, with the type and extent of resource impact influenced by factors such as soil texture, topography, climate, trail design and maintenance, and type and amount of use. Of particular concern, the loss of soil through erosion is generally considered a significant and irreversible form of trail impact. This research investigated the influence of several use-related, environmental, and managerial factors on soil loss on recreational trails and roads at Big South Fork National River and Recreation Area, a unit of the U.S. National Park Service. Regression modeling revealed that trail position, trail slope alignment angle, grade, water drainage, and type of use are significant determinants of soil loss. The introduction of individual and groups of variables into a series of regression models provides improved understanding and insights regarding the relative influence of these variables, informing the selection of more effective trail management actions. Study results suggest that trail erosion can be minimized by avoiding “fall-line” alignments, steep grades, and valley-bottom alignments near streams, installing and maintaining adequate densities of tread drainage features, applying gravel to harden treads, and reducing horse and all-terrain vehicle use or restricting them to more resistant routes.     

Application of a hurdle negative binomial count data model to demand for bass fishing in the southeastern United States

This paper identifies factors that influence the demand for a bass fishing trip taken in the southeastern United States using a hurdle negative binomial count data model. The probability of fishing for a bass is estimated in the first stage and the fishing trip frequency is estimated in the second stage for individuals reporting bass fishing trips in the Southeast. The applied approach allows the decomposition of the effects of factors responsible for the decision to take a trip and the trip number. Calculated partial and total elasticities indicate a highly inelastic demand for the number of fishing trips as trip costs increase. However, the demand can be expected to increase if anglers experience a success measured by the number of caught fish or their size. Benefit estimates based on alternative estimation methods differ substantially, suggesting the need for testing each modeling approach applied in empirical studies.     

Qualitative impacts of Senna spectabilis on distribution of welfare: A household survey of dependent communities in Budongo Forest Reserve,Uganda

This paper presents the results of a household survey designed to qualitatively evaluate the impacts of the invasive alien species Senna spectabilis on the distribution of welfare across dependent communities in the Budongo Forest Reserve (BFR) in Uganda. The BFR is the largest forest reserve in Uganda, with globally significant conservation values. The study establishes that households in the BFR have high levels of knowledge as to its conservation values; they are aware of the invasiveness of S. spectabilis and its potential to compromise the conservation values of the BFR, and that S. spectabilis confers tangible benefits to dependent households, whose levels significantly vary with proximity to the reserve. The study concludes by evaluating strategies that are designed to manage the spread of S. spectabilis in the BFR and which consider its demonstrated socio‐economic impacts.     

Improving the Integration of Recreation Management with Management of Other Natural Resources by Applying Concepts of Scale from Ecology

In this article, we examine how issues of scale affect the integration of recreation management with the management of other natural resources on public lands. We present two theories used to address scale issues in ecology and explore how they can improve the two most widely applied recreation-planning frameworks. The theory of patch dynamics and hierarchy theory are applied to the recreation opportunity spectrum (ROS) and the limits of acceptable change (LAC) recreation-planning frameworks. These frameworks have been widely adopted internationally, and improving their ability to integrate with other aspects of natural resource management has significant social and conservation implications. We propose that incorporating ecologic criteria and scale concepts into these recreation-planning frameworks will improve the foundation for integrated land management by resolving issues of incongruent boundaries, mismatched scales, and multiple-scale analysis. Specifically, we argue that whereas the spatially explicit process of the ROS facilitates integrated decision making, its lack of ecologic criteria, broad extent, and large patch size decrease its usefulness for integration at finer scales. The LAC provides explicit considerations for weighing competing values, but measurement of recreation disturbances within an LAC analysis is often done at too fine a grain and at too narrow an extent for integration with other recreation and resource concerns. We suggest that planners should perform analysis at multiple scales when making management decisions that involve trade-offs among competing values. The United States Forest Service is used as an example to discuss how resource-management agencies can improve this integration.     

Heavy metal content and distribution in surface sediments of the Seyhan River, Turkey

Chemical fractionation of seven heavy metals (Cd, Cr, Cu, Mn, Ni, Pb and Zn) was studied using a modified three-step sequential procedure to assess their impacts in the sediments of the Seyhan River, Turkey. Samples were collected from six representative stations in two campaigns in October 2009 and June 2010, which correspond to the wet and dry seasons, respectively. The total metal concentrations in the sediments demonstrated different distribution patterns at the various stations. Cadmium was the only metal that was below detection at all stations during both sampling periods. Metal fractionation showed that, except for Mn and Pb, the majority of metals were found in the residual fraction regardless of sampling time, indicating that these metals were strongly bound to the sediments. The potential mobility of the metals (non-residual fractions) is reflected in the following ranking: Pb > Mn > Zn > Cu > Ni > Cr in October 2009 and Mn > Pb > Zn > Cu > Ni > Cr in June 2010. The second highest proportion of metals was bound to organic matter/sulfides, originating primarily from anthropogenic activities. Non-residual metal fractions for all stations were highest in June 2010, which may be linked to higher organic matter concentrations in the sediment samples with 1.40% and 15.1% in October 2009 and June 2010, respectively. Potential sediment toxicity was evaluated using the Risk Assessment Code (RAC). Based on RAC classification, Cd and Cr pose no risk, Cu and Ni pose low risk, Pb and Zn were classified as medium risk metals, while the environmental risk from Mn was high. In addition, based on the sediment quality guidelines (SQG), the Seyhan River can be classified as a river with no, to moderate, toxicological risks, based on total metal concentrations.     

Development of a risk-based index for source water protection planning, which supports the reduction of pathogens from agricultural activity entering water resources

Source water protection planning (SWPP) is an approach to prevent contamination of ground and surface water in watersheds where these resources may be abstracted for drinking or used for recreation. For SWPP the hazards within a watershed that could contribute to water contamination are identified together with the pathways that link them to the water resource. In rural areas, farms are significant potential sources of pathogens. A risk-based index can be used to support the assessment of the potential for contamination following guidelines on safety and operational efficacy of processes and practices developed as beneficial approaches to agricultural land management. Evaluation of the health risk for a target population requires knowledge of the strength of the hazard with respect to the pathogen load (massxconcentration). Manure handling and on-site wastewater treatment systems form the most important hazards, and both can comprise confined and unconfined source elements. There is also a need to understand the modification of pathogen numbers (attenuation) together with characteristics of the established pathways (surface or subsurface), which allow the movement of the contaminant species from a source to a receptor (water source). Many practices for manure management have not been fully evaluated for their impact on pathogen survival and transport in the environment. A key component is the identification of potential pathways of contaminant transport. This requires the development of a suitable digital elevation model of the watershed for surface movement and information on local groundwater aquifer systems for subsurface flows. Both require detailed soils and geological information. The pathways to surface and groundwater resources can then be identified. Details of land management, farm management practices (including animal and manure management) and agronomic practices have to be obtained, possibly from questionnaires completed by each producer within the watershed. To confirm that potential pathways are active requires some microbial source tracking. One possibility is to identify the molecular types of Escherichia coli present in each hazard on a farm. An essential part of any such index is the identification of mitigation strategies and practices that can reduce the magnitude of the hazard or block open pathways.     

吉东山区总辐射资源的地理空间分布特征

本文以地理纬度、经度和海拔高度为因子,采用二次趋势面函数,建立了描述吉林省东部长白山区年总辐射、5～9月总辐射和日平气温稳定通过10℃期间的总辐射资源的地理空间分布特征的数学模式。采用地理细网格场的分析方法,揭示了该山区总辐射资源的空间分布情况。     

A quantitative technique for estimating the boundaries of wetlands from vegetation data

There is an increasing need for the accurate delineation of wetlands for planning and conservation purposes. We propose a method based on vegetation zonation which requires three steps. The first step is to examine transects crossing the transition zone from marsh to upland. In each transect the uppermost occurrence of each plant species is located relative to a fixed survey point. The second step is to determine which of these species are hydrophytes (wetland plants). This is assessed using the presence or absence of morphological and physiological adaptations for growing in wet environments. Alternatively, a literature search using botanical manuals may suffice. The third step determines the upper limit of the wetland by finding the upper limit of the uppermost hydrophyte in each transect, and taking the mean value of these over all transects. This mean defines the boundary of the wetland. The method is illustrated using two marshes along the north shore of the St. Lawrence River in Ontario.     

Evidence of hydrocarbon contamination from the Burgan oil field, Kuwait: interpretations from thermal remote sensing data

The paper presents the application of thermal remote sensing for mapping hydrocarbon polluted sites. This has been achieved by mono-window algorithm for land surface temperature (LST) measurements, using multi-date band 6 data of Landsat Thematic Mapper (TM). The emissivity, transmittance and mean atmospheric temperature were used as critical factors to estimate LST. The changes in the surface emissivity due to oil pollution alter the apparent temperature, which was used as a recognition element to map out oil polluted surfaces. The LST contrast was successfully used to map spatial distribution of hydrocarbon pollution in the Burgan Oil field area of Kuwait. The methodology can be positively used to detect waste dumping, oil spills in oceans and ports, besides environmental management of oil pollution at or near the land surface.     

四川省2010~2019年突发环境事件时空分布特征分析

近年来,四川省高度重视环境应急管理工作,环境应急处置能力不断提升,但环境风险形势依然严峻,突发环境事件时有发生。通过对2010~2019年四川省10年突发环境事件进行统计分析,浅析四川省突发环境事件的规律特点,以期为四川省生态环境风险防控提供科学依据。研究表明,四川省突发环境事件呈现多发高发态势,6~8月为突发环境事件高发期;安全生产事故和交通事故次生的突发环境事件是主要事件类型;成都市和广元市是突发环境事件的高发区域;油类污染物和酸碱类污染物是主要污染物类型;跨界流域突发环境事件发生频率较高。应从流域突发环境事件风险评估、企业环境安全主体责任、环境应急物质储备体系和突发环境事件联防联控等方面加强四川省环境应急管理。     

四川乌头和附子气候生态适宜性研究

本文在分析乌头和附子的生态要求及其主要分布产区的气候环境的基础上,根据模糊集合论(Fuzzy sets)分别建立乌头和附子5个生态气候要素的隶属函数模型,以50个市(县)气象台(站)为代表,综合评价了四川省乌头和附子产地气候条件的生态适宜性;根据综合评判结果,分别将四川划分为3个乌头不同适宜区和4个附子不同适宜区。     

Assessing the environmental performance of English arable and livestock holdings using data from the Farm Accountancy Data Network (FADN)

Agri-environment schemes (AESs) have been implemented across EU member states in an attempt to reconcile agricultural production methods with protection of the environment and maintenance of the countryside. To determine the extent to which such policy objectives are being fulfilled, participating countries are obliged to monitor and evaluate the environmental, agricultural and socio-economic impacts of their AESs. However, few evaluations measure precise environmental outcomes and critically, there are no agreed methodologies to evaluate the benefits of particular agri-environmental measures, or to track the environmental consequences of changing agricultural practices. In response to these issues, the Agri-Environmental Footprint project developed a common methodology for assessing the environmental impact of European AES. The Agri-Environmental Footprint Index (AFI) is a farm-level, adaptable methodology that aggregates measurements of agri-environmental indicators based on Multi-Criteria Analysis (MCA) techniques. The method was developed specifically to allow assessment of differences in the environmental performance of farms according to participation in agri-environment schemes. The AFI methodology is constructed so that high values represent good environmental performance. This paper explores the use of the AFI methodology in combination with Farm Business Survey data collected in England for the Farm Accountancy Data Network (FADN), to test whether its use could be extended for the routine surveillance of environmental performance of farming systems using established data sources. Overall, the aim was to measure the environmental impact of three different types of agriculture (arable, lowland livestock and upland livestock) in England and to identify differences in AFI due to participation in agri-environment schemes. However, because farm size, farmer age, level of education and region are also likely to influence the environmental performance of a holding, these factors were also considered. Application of the methodology revealed that only arable holdings participating in agri-environment schemes had a greater environmental performance, although responses differed between regions. Of the other explanatory variables explored, the key factors determining the environmental performance for lowland livestock holdings were farm size, farmer age and level of education. In contrast, the AFI value of upland livestock holdings differed only between regions. The paper demonstrates that the AFI methodology can be used readily with English FADN data and therefore has the potential to be applied more widely to similar data sources routinely collected across the EU-27 in a standardised manner.     

Heavy metal distribution in crab (<Emphasis Type="Italic">Callinectes amnicola</Emphasis>) living on the shores of Ojo Rivers,Lagos, Nigeria

Crab samples, both male and female specie, were purchased from fishermen at the Ojo Rivers, Lagos, Nigeria. The samples separated into abdomen, muscle tissue, and thorax were oven dried at 80°C for 3 days. The dried samples were then pulverized in a clean acid-washed mortar and pestle. Approximately 1.00 g each of the pulverized samples was weighed and Zn, Cr, Pb, and Cd were determined in the solution of the aqua regia digested samples by means of AAS (Buck Scientific 210 GVP model). The results obtained showed Zn metal to be consistently higher in all the female parts compared to the male with values of 12.92 ± 3.65 μg/g to 16.03 ± 1.08 μg/g and 9.33 ± 1.77 μg/g to 15.75 ± 1.02 μg/g, respectively. Mean values of 0.39 ± 0.09 μg/g and 0.22 ± 0.02 μg/g cadmium were found in the abdomen and tissue of the male crab as against 0.35 ± 0.07 μg/g and 0.17 ± 0.07 μg/g in the female crab. The tissues of both species have comparable value of chromium. Lead was below the detection limit of 0.05 μg/g in the tissues of male crab but the female tissue contained 0.83 ± 0.13 μg/g and in other parts identified, lead was consistently higher than the 2.00 μg/g permissible level of WHO in foods. A simple pair t-test did not demonstrate any significant difference in the distribution of metals between the male and female crabs. The coefficient of variation (CV) calculated for each metal with respect to the studied parts showed Pb to be widely distributed (56.23–89.54%) while Cr did not vary widely (4.17–8.20%).     

Study of Fractionation and Potential Mobility of Metal from the Guadalquivir Estuary: Changes in Mobility with Time and Influence of the Aznalcollar Mining Spill

This study analyzed the evolution of metal levels in surface sediments from the Guadalquivir estuary between 1997 and 2002 and assessed the impact of the April 1998 Aznalcollar tailings dam failure and subsequent cleanup on metal concentrations in surface sediments. We also analyzed metal distribution with time in five chemical fractions of the surface sediments: exchangable, carbonate, reducible, oxidizable, and residual. This work showed that the April 1998 Aznalcollar tailings dam failure caused a considerable increase in the concentrations of Cd, Zn, Cu, and Pb in the surface sediments of the Guadalquivir estuary. It was also found there was a change in the distribution of Cd, Zn, Cu, and Pb between the chemical fractions of the sediment after the failure of the dam. There were increases in the percentages of Cd in the carbonate fraction, of Zn and Pb in the reducible fraction, and of Cu in the oxidizable fraction, whereas the percentages of these elements associated with the residual fraction decreased. In 1999, there was a decrease in the metal concentrations in the surface sediments from the Guadalquivir estuary, and by 2000 the chemical distribution and metal levels had returned to levels similar those before the dam failure.     

Evaluating the aesthetic value of cultural ecosystem services by mapping geo-tagged photographs from social media data on Panoramio and Flickr

Traditional approaches for evaluating aesthetic value rely on surveys or interviews. Social media provides a new type of crowdsourcing data to examine the relationships between aesthetic value and citizens' activities. The main goal of this paper was to evaluate aesthetic value in Nebraska by using citizen-reported geo-tagged photographs posted on two social media sites – Panoramio and Flickr. The study used the application programming interface from Panoramio and Flickr to obtain the latitude and longitude of the geo-tagged photographs, and then used ArcGIS spatial statistical tools to examine spatial patterns with areas of aesthetic value in Nebraska. The outcomes identified the clusters of pictures with the locations of ecosystem service provisioning areas of aesthetic value in Nebraska, identified new areas with aesthetic value, and drew comparisons with local and regional population distribution. This study provided an innovative approach to using crowdsourcing data to verify the value of ecosystem services.     

Economic impact measurement and evaluation of China's investment in geological exploration: The empirical analysis based on the data from 1999 to 2009

With the continued growth in demand for mineral resources and China's efforts in increasing investment in geological prospecting, economic impact evaluation of geological exploration becomes a research hotspot.     

A critical review of hydrological data collection for assessing preservation risk for urban waterlogged archaeology: A case study from the City of York, UK

Environmental change caused by urban development, possibly augmented by climate change, may result in accelerated decay of in situ archaeological resources. Damage may be related to changes in hydrological processes. Such archaeological resources have to be considered in environmental planning. In this paper we highlight the need for improved hydrological data from urban archaeological sites using the case study of the City of York, UK, arguably one of the most well studied and well preserved urban archaeological environments globally. We suggest that the quality of hydrological data collected during routine surveys and experimental work must be improved and standardised in order for us to produce reliable archaeological risk models for urban sites.     

The use of aggregate complaints data as an indicator of cumulative social impacts of mining: A case study from the Hunter valley,NSW, Australia

Generally speaking, there is a greater amount of quantitative data available to measure and model the cumulative environmental or economic impacts of mining than the social impacts. In part, this is because social impacts are often inherently more difficult to quantify, but historically there have also been fewer regulatory drivers for companies or state agencies to invest in collecting such data. Regulators in some jurisdictions are now starting to require resource companies to report on aspects of their social performance, but companies and regulators are still struggling to identify appropriate metrics, particularly in regards to cumulative impacts. This paper describes an innovative quantitative approach to tracking how communities experience and respond to increased mining activity, using data from the complaints registers maintained by mines located in the Upper Hunter Valley in New South Wales, Australia. In this study, complaints lodged with five separate mines adjacent to the township of Muswellbrook over several years were aggregated and trends analysed. The aggregated set showed that complaint frequency increased with the increase in mining activity but then decreased as individual complaints were addressed. However, when complaints from near-neighbours were removed, it emerged that the proportion of complaints that came from the town itself steadily increased over time. Further analysis indicated that this increase was closely associated with the amount of mine-disturbed land that could be seen from the town over time, as measured using a combination of remotely sensed data and a digital elevation model. This is persuasive evidence of a cumulative social impact that is more than just the sum of the local impacts of individual mines.