The effect of visitors’ pressure on the spatial variability of sandy soil in an urban parks in Tel Aviv

The effect of visitors' pressure on the spatial variability of soil properties was investigated in three open green areas in Tel Aviv. Six types of micro-environments were chosen: under oak and pine tree canopy with low (OL and PL) and high (OH and PH) visitors' pressure; herbaceous area without visitors' pressure (HE); and resting area under high visitors' pressure (RA). For each micro-environment soil samples were collected from the upper 0-5 cm depth for organic matter content and moisture determination. Before sampling, soil surface compaction and litter biomass were measured. Soil properties were affected by visitors' pressure and by the type of micro-environment. Soil organic matter content and soil moisture proved significantly higher under oak trees at low visitors' pressure. Average litter biomass significantly decreased with increasing visitors' pressure in the tree micro-environments. Average penetration depth decreased significantly with increased visitors' pressure in all micro-environments. In all the cases where averages significantly decreased, variance significantly decreased too, but the coefficient of variations increased. This means that variances changed slower than averages. Changes in averages were accompanied by a change of data population structure, which indicated more soil spatial homogeneity under high visitors' pressure. The data from different intervals of data population of soil properties demonstrated the different sensitivity to visitors' pressure.     

Toward ‘good process’ in regulatory reviews: Is Canada’s new system any better than the old?

What are the features of a good regulatory review process? In this paper we identify criteria for ‘good process’ drawn from a combined reading of the environmental justice and process literature. We then apply these criteria to a case study, assessing four versions of Canadian regulatory review: CEAA 1992, CEAA 2012, the 2017 Expert Panel report, and IAA 2019. We aim to make two contributions. First, we propose a set of ‘good process’ criteria that we hope can be widely applied, reflecting on complementarities and tensions that arise from combining two bodies of scholarship. Second, we identify areas where Canadian review processes have improved over time and those where significant work remains to be done. This work seeks to make a constructive intervention at a time when energy and industrial projects around the world face strong challenges in the legal, political and public domains.     

A study on the determination of the natural park’s sustainable tourism potential

The surface site of Yesilyuva Nature Park encompasses natural, social, economic, and cultural characteristics and has become a marker of the region’s natural and cultural heritage. To support the preservation of this site, promotional activities should be planned. In this study, because of tourism and related opinions of residents and visitors alike in terms of their natural determination, an important cultural and historical feature is aimed at evaluating the tourism potential of Yesilyuva Nature Park. This framework is designed to establish prospective tourism sustainability. As a result, Yesilyuva Nature Park’s natural and cultural properties have been determined to be suitable for sustainable tourism activities using geographic information systems (GIS). This protection in the field, which balances sustainability and landscape design, will provide for the development of tourism activities. In the Strengths, Weaknesses, Opportunities and Threats (SWOT) analysis and survey, residents and visitors reported that the most important feature of the Yesilyuva Nature Park was its natural beauty. Visitors often come to observe traditional and natural life and to engage in tourism activities. All the data, which includes maps derived from GIS, represents landscape planning for sustainable tourism areas in Yesilyuva Nature Park.     

Application of the probability-based Maryland Biological Stream Survey to the state’s assessment of water quality standards

The Clean Water Act presents a daunting task for states by requiring them to assess and restore all their waters. Traditional monitoring has led to two beliefs: (1) ad hoc sampling (i.e., non-random) is adequate if enough sites are sampled and (2) more intensive sampling (e.g., collecting more organisms) at each site is always better. We analyzed the 1,500 Maryland Biological Stream Survey (MBSS) random sites sampled in 2000–2004 to describe the variability of Index of Biotic Integrity (IBI) scores at the site, reach, and watershed scales. Average variability for fish and benthic IBI scores increased with increasing spatial scale, demonstrating that single site IBI scores are not representative at watershed scales and therefore at best 25% of a state’s stream length can be representatively sampled with non-random designs. We evaluated the effects on total taxa captured and IBI precision of sampling for twice as many benthic macroinvertebrates at 73 MBSS sites with replicate samples. When sampling costs were fixed, the precision of the IBI decreased as the number of sites had to be reduced by 15%. Only 1% more taxa were found overall when the 73 sites where combined. We concluded that (1) comprehensive assessment of a state’s waters should be done using probability-based sampling that allows the condition across all reaches to be inferred statistically and (2) additional site sampling effort should not be incorporated into state biomonitoring when it will reduce the number of sites sampled to the point where overall assessment precision is lower.     

Assessing the Effects of Non-Point Source Pollution on American Samoa’s Coral Reef Communities

Surveys were completed on Tutuila Island, American Samoa, to characterize reef development and assess the impacts of non-point source pollution on adjacent coral reefs at six sites. Multivariate analyses of benthic and coral community data found similar modern reef development at three locations; Aoa, Alofau, and Leone. These sites are situated in isolated bays with gentle sloping foundations. Aoa reefs had the highest estimates of crustose coralline algae cover and coral species richness, while Leone and Alofau showed high abundances of macroalgae and Porites corals. Aoa has the largest reef flat between watershed discharge and the reef slope, and the lowest human population density. Masefau and Fagaalu have a different geomorphology consisting of cemented staghorn coral fragments and steep slopes, however, benthic and coral communities were not similar. Benthic data suggest Fagaalu is heavily impacted compared with all other sites. Reef communities were assessed as bio-criteria indicators for waterbody health, using the EPA aquatic life use support designations of (1) fully supportive, (2) partially supportive, and (3) non-supportive for aquatic life. All sites resulted in a partially supportive ranking except Fagaalu, which was non-supportive. The results of this rapid assessment based upon relative benthic community measures are less desirable than long-term dataset analyses from monitoring programs, however it fills an important role for regulatory agencies required to report annual waterbody assessments. Future monitoring sites should be established to increase the number of replicates within each geological and physical setting to allow for meaningful comparisons along a gradient of hypothesized pollution levels.     

Economic Impacts of Changes in Fish Population Dynamics: The Role of the Fishermen’s Harvesting Strategies

Using a bioeconomic model of the cod (Gadus morhua) and capelin (Mallotus villosus) fisheries of the Barents Sea, this study assesses the role of the fishermen’s behavior in reducing or intensifying the effects on the stocks caused by altered population dynamics. The analysis focuses on the economic development of the fisheries employing a coupled stock size–hydrography-based fishing strategy, which attempts to maximize returns from fishing over a given number of fishing periods. Results show that if the fishing strategy is based on a short optimization period of only two fishing periods, changes in population dynamics have a direct influence on the returns from fishing due to the strong pressure on the stocks applied by the fisheries. If the strategy is based on a longer optimization period, fishing activities may be deferred to allow for stock regrowth, which improves the economic performance of the fisheries. However, in that case, the relationship between population dynamics and fishing activities becomes less clear, as even a reduction of the carrying capacities of the two species allows for an increase in the amount of fish landed without causing a stock collapse due to an increased efficiency of fleet utilization. The simulations indicate that management considerations and the time horizon of the fishing strategy dominate the influence of altered population dynamics on the development of the stocks considered in the model.     

Evaluation of forest nutrition based on large-scale foliar surveys: are nutrition profiles the way of the future?

This paper introduces the use of nutrition profiles as a first step in the development of a concept that is suitable for evaluating forest nutrition on the basis of large-scale foliar surveys. Nutrition profiles of a tree or stand were defined as the nutrient status, which accounts for all element concentrations, contents and interactions between two or more elements. Therefore a nutrition profile overcomes the shortcomings associated with the commonly used concepts for evaluating forest nutrition. Nutrition profiles can be calculated by means of a neural network, i.e. a self-organizing map, and an agglomerative clustering algorithm with pruning. As an example, nutrition profiles were calculated to describe the temporal variation in the mineral composition of Scots pine and Norway spruce needles in Finland between 1987 and 2000. The temporal trends in the frequency distribution of the nutrition profiles of Scots pine indicated that, between 1987 and 2000, the N, S, P, K, Ca, Mg and Al decreased, whereas the needle mass (NM) increased or remained unchanged. As there were no temporal trends in the frequency distribution of the nutrition profiles of Norway spruce, the mineral composition of the needles of Norway spruce needles subsequently did not change. Interpretation of the (lack of) temporal trends was outside the scope of this example. However, nutrition profiles prove to be a new and better concept for the evaluation of the mineral composition of large-scale surveys only when a biological interpretation of the nutrition profiles can be provided.     

Distribution of heavy metals in the dissolved and suspended phase of the sea-surface microlayer, seawater column and in sediments of Singapore’s coastal environment

Concentrations of heavy metals were determined in the water column (including the sea-surface microlayer, subsurface, mid-depth and bottom water) and sediments from Singapore’s coastal environment. The concentration ranges for As, Cd, Cr, Cu, Ni, Pb and Zn in the seawater dissolved phase (DP) were 0.34–2.04, 0.013–0.109, 0.07–0.35, 0.23–1.16, 0.28–0.78, 0.009–0.062 and 0.97–3.66 μg L⁻¹ respectively. The ranges for Cd, Cr, Cu, Ni, Pb and Zn in the suspended particulate matter (SPM) were 0.16–0.73, 6.72–53.93, 12.87–118.29, 4.34–60.71, 1.10–6.08 and 43.09–370.49 μg g⁻¹, respectively. Heavy metal concentrations in sediments ranged between 0.054–0.217, 37.48–50.52, 6.30–21.01, 13.27–26.59, 24.14–37.28 and 48.20–62.36 μg g⁻¹ for Cd, Cr, Cu, Ni, Pb and Zn, respectively. The lowest concentrations of metals in the DP and SPM were most frequently found in the subsurface water while the highest concentrations were mostly observed in the SML and bottom water. Overall, heavy metals in both the dissolved and particulate fractions have depth profiles that show a decreasing trend of concentrations from the subsurface to the bottom water, indicating that the prevalence of metals is linked to the marine biological cycle. In comparison to data from Greece, Malaysia and USA, the levels of metals in the DP are considered to be low in Singapore. Higher concentrations of particulate metals were reported for the Northern Adriatic Sea and the Rhine/Meuse estuary in the Netherlands compared to values reported in this study. The marine sediments in Singapore are not heavily contaminated when compared to metal levels in marine sediments from other countries such as Thailand, Japan, Korea, Spain and China.     

Toxicity assessment of sediments associated with the wreck of s/s Stuttgart in the Gulf of Gdańsk (Poland)

The paper presents the results of toxicity determinations carried out on sediment samples collected in the vicinity of the wreck of the German s/s Stuttgart (the southern part of the Gulf of Gdańsk, off the Polish coast) in relation to the determination of polycyclic aromatic hydrocarbons (PAHs). The toxicity of surface and core sediment samples was assessed using two biotest organisms-the bioluminescent bacteria Vibrio fischeri and the ostracod Heterocypris incongruens. PAH levels in these samples were determined by GC-MS. The surface sediments collected at W2 (ca. 34 m north of the shipwreck) and W4 (ca. 415 m north-east of the wreck) as well as the core sediments collected at WR3 (ca. 400 m north-east of the wreck) were the most heavily polluted with substances toxic to the biotest organisms. The chronic and acute toxicities in the case of most of the surface sediment samples studied are correlated. This may suggest that not only hydrophobic chemicals (like PAHs from fuel residues) but also more polar chemicals (resulting from the conversion of aromatic hydrocarbons) are responsible for the toxicity levels found. There is a clear dependence between the levels of chronic toxicity and PAH concentrations in the core sediment samples. In addition, a simultaneous decrease in the PAH content and chronic toxicity was noted in all the core sediment samples at depths below 80 cm.     

Integrating sentinel watershed-systems into the monitoring and assessment of Minnesota’s (USA) waters quality

Section 303(d) of the Clean Water Act requires States and Tribes to list waters not meeting water quality standards. A total maximum daily load must be prepared for waters identified as impaired with respect to water quality standards. Historically, the management of pollution in Minnesota has been focused on point-source regulation. Regulatory effort in Minnesota has improved water quality over the last three decades. Non-point source pollution has become the largest driver of conventional 303(d) listings in the 21st century. Conventional pollutants, i.e., organic, sediment and nutrient imbalances can be identified with poor land use management practices. However, the cause and effect relationship can be elusive because of natural watershed-system influences that vary with scale. Elucidation is complex because the current water quality standards in Minnesota were designed to work best with water quality permits to control point sources of pollution. This paper presents a sentinel watershed-systems approach (SWSA) to the monitoring and assessment of Minnesota waterbodies. SWSA integrates physical, chemical, and biological data over space and time using advanced technologies at selected small watersheds across Minnesota to potentially improve understanding of natural and anthropogenic watershed processes and the management of point and non-point sources of pollution. Long-term, state-of-the-art monitoring and assessment is needed to advance and improve water quality standards. Advanced water quality or ecologically-based standards that integrate physical, chemical, and biological numeric criteria offer the potential to better understand, manage, protect, and restore Minnesota’s waterbodies.     

Measurement Research on the Influence of China’s Provincial Technological Innovation Capacity upon Green Economy Development

Environmental Modeling & Assessment - Based on the global entropy method to evaluate the technological innovation ability and the development level of green economy in Chinese provinces from...     

A synoptic survey of select wastewater-tracer compounds and the pesticide imidacloprid in Florida’s ambient freshwaters

Current wastewater treatment technologies do not remove many unregulated hydrophilic compounds, and there is growing interest that low levels of these compounds, referred to as emerging contaminants, may impact human health and the environment. A probabilistic-designed monitoring network was employed to infer the extent of Florida’s ambient freshwaters containing the wastewater (Includes reuse water, septic systems leachate, and wastewater treatment effluent.) indicators sucralose, acetaminophen, carbamazepine, and primidone and those containing the widely used pesticide imidacloprid. Extent estimates with 95% confidence bounds are provided for canals, rivers, streams, small and large lakes, and unconfined aquifers containing ultra-trace concentrations of these compounds as based on analyses of 2015 sample surveys utilizing 528 sites. Sucralose is estimated to occur in greater than 50% of the canal, river, stream, and large lake resource extents. The pharmaceuticals acetaminophen, carbamazepine, and primidone are most prevalent in rivers, with approximately 30% of river kilometers estimated to contain at least one of these compounds. Imidacloprid is estimated to occur in 50% or greater of the canal and river resource extents, and it is the only compound found to exceed published toxicity or environmental effects standards. Geospatial analyses show sucralose detection frequencies within Florida’s drainage basins to be significantly related to the percentage of urban land use (R²?=?0.36, p?<?0.001), and imidacloprid detection frequencies to be significantly related to the percentage of urban and agricultural land use (R²?=?0.47, p?<?0.001). The extent of the presence of these compounds highlights the need for additional emerging contaminant studies especially those examining effects on aquatic biota.     

Trophic dynamics of U, Ni, Hg and other contaminants of potential concern on the Department of Energy’s Savannah River Site

The Department of Energy’s Savannah River Site is a former nuclear weapon material production and current research facility located in South Carolina, USA. Wastewater discharges from a fuel and nuclear reactor target manufacturing facility released depleted and natural U, as well as other metals into the Tims Branch-Steed Pond water system. We investigated the current dynamics of this system for the purposes of environmental monitoring and assessment by examining metal concentrations, bioavailability, and trophic transfer of contaminants in seven ponds. Biofilm, detritus, and Anuran and Anisopteran larvae were collected and analyzed for stable isotopes (δ ¹⁵N, δ ¹³C) and contaminants of potential concern (COPC) with a focus on Ni, U, and Hg, to examine metal mobility. Highest levels of Ni and U were found in biofilms U (147 and 332 mg kg^?1 DW, respectively), while highest Hg levels were found in tadpoles (1.1 mg kg^?1 DW). We found intraspecific biomagnification of COPCs as expressed through stable isotope analysis. Biofilms were the best indicators for contamination and Anuran larvae with the digestive tract removed were the best indicators of the specific bioavailability of the focal metals. Monitoring data showed that baseline δ ¹⁵N values differed between ponds, but within a pond, values were stable throughout tadpole Gosner stage, strengthening the case to use this species for monitoring purposes. It is likely that there still is risk to ecosystem integrity as COPC metals are being assimilated into lower trophic organisms and even low levels of this mixture has shown to produce deleterious effects to some wildlife species.     

Sources of volatile organic compounds in Cairo’s ambient air

The greater Cairo area suffers from extreme levels of gas and particulate phase air pollutants. In order to reduce the levels of ambient pollution, the USAID and the Egyptian Environmental Affairs Agency (EEAA) have supported the Cairo Air Improvement Project (CAIP). As part of this project, two intensive ambient monitoring studies were carried out during the period of February 22 to March 4 and October 27 to November 27, 1999. Volatile organic compounds (VOCs) were measured on a 24-h basis at six sampling stations during each of the intensive periods. During the February/March study, samples were collected daily, while in the October/November study samples were collected every other day. The six intensive measurement sites represented background levels, mobile source impacts, industrial impacts, and residential exposure. High levels of NMHC were observed at all locations. NMHC concentrations ranged from 365 ppb C at Helwan to 1,848 ppb C at El Qualaly during winter, 1999 and from 461 ppb C at Kaha to 2,037 ppb C at El Qualaly during fall, 1999. El Qualaly, the site chosen to represent mobile emissions, displayed the highest average NMHC concentrations of any site, by a factor of 2 or more. The highest mobile source contributions were estimated at this site. The major contributors to NMHC at all sites were mobile emissions, lead smelting, and compressed natural gas.     

Development and testing of an index of biotic integrity based on submersed and floating vegetation and its application to assess reclamation wetlands in Alberta’s oil sands area,Canada

We developed and tested a plant-based index of biological integrity (IBI) and used it to evaluate the existing reclamation wetlands in Alberta’s oil sands mining region. Reclamation plans call for >15,000 ha of wetlands to be constructed, but currently, only about 25 wetlands are of suitable age for evaluation. Reclamation wetlands are typically of the shallow open water type and range from fresh to sub-saline. Tailings-contaminated wetlands in particular may have problems with hydrocarbon- and salt-related toxicity. From 60 initial candidate metrics in the submersed aquatic and floating vegetation communities, we selected five to quantify biological integrity. The IBI included two diversity-based metrics: the species richness of floating vegetation and the percent of total richness contributed by Potamogeton spp. It also included three relative abundance-based metrics: that of Ceratophyllum demersum, of floating leafed species and of alkali-tolerant species. We evaluated the contribution of nonlinear metrics to IBI performance but concluded that the correlation between IBI scores and wetland condition was not improved. The method used to score metrics had an influence on the IBI sensitivity. We conclude that continuous scoring relative to the distribution of values found in reference sites was superior. This scoring approach provided good sensitivity and resolution and was grounded in reference condition theory. Based on these IBI scores, both tailings-contaminated and tailings-free reclamation wetlands have significantly lower average biological integrity than reference wetlands (ANOVA: F _2,59 = 34.7, p = 0.000000000107).     

Soil solution and sugar maple response to NH4NO3 additions in a base-poor northern hardwood forest of Québec, Canada

Nitrogen additions (NH4NO3) at rates of three- and ten-fold ambient atmospheric deposition (8.5 kg ha(-1) year(-1)) were realised in an acid- and base-poor northern hardwood forest of Québec, Canada. Soil solution chemistry, foliar chemistry, crown dieback and basal area growth of sugar maple (Acer saccharum Marsh.) were measured. Except for a transitory increase of NO3 and NH4 concentrations, there was no persistent increase in their level in soil solution 3 years after N treatments, with the exception of one plot out of three, that received the highest N addition, beginning to show persistent and high NO3 concentrations after 2 years of N additions. Three years of N additions have significantly increased the N DRIS index of sugar maple but not N foliar concentration. Potassium, Ca and Mn foliar concentrations, as well as P and Ca DRIS indices, decreased in treated plots after 3 years. No treatment effect was observed for basal area growth and dieback rate. One unexpected result was the significant decrease in foliar Ca even in the treated plots that received low N rates, despite the absence of significant NO3-induced leaching of Ca. The mechanism responsible for the decrease in foliar Ca is not known. Our results, however, clearly demonstrate that increased N deposition at sites with low base saturation may affect Ca nutrition even when clear signs of N saturation are not observed.