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Marine protected areas (MPAs) are used as fisheries management and conservation tools. Well-enforced no-take zones allow the rebuilding of natural populations of exploited species; however, there is still controversy on the role of buffer zones. The effectiveness of MPAs could be underestimated, as fish population assessments depend largely on traditional methodologies that have difficulties in detecting predatory fish because of their low abundances, their patchy distribution, and their reaction to the presence of divers. The performance of different census methods was compared in assessing the protection benefits for large predatory fishes under different protection levels (i.e. no-take and buffer zones) in five Mediterranean MPAs. Specifically, conventional strip transects (CSTs, 50 × 5 m2) and tracked roaming transects combined with distance sampling (TRT + DS, variable lengths) were compared, including a series of TRT-derived estimators with variable transect lengths and fixed widths of 20, 10, and 6 m (TRT20, TRT10, and TRT6, respectively). Additionally, the effectiveness of the MPAs studied and protection levels for conserving large predatory species was evaluated. Transects covering larger areas (i.e. TRT + DS and TRT20) allowed the detection of a greater number of species and yielded more accurate estimates of density and biomass than transects of narrower fixed widths, particularly the CSTs, which were associated with the lowest richness detection capability, accuracy, and precision. On average, both no-take zones and buffer zones appeared effective for the conservation of predatory fishes, indicating that multiple protection areas were ecologically effective. Differences between MPAs were also observed, however, probably arising from both local environmental and management factors. We suggest the implementation of methodologies with larger transects for the study of large predatory fish, combined with CSTs for the rest of the fish community, in order to avoid biases in predatory population assessments, which are key indicators of MPA effectiveness.

Macroinvertebrate assemblages are structured by a number of abiotic and biotic factors interacting simultaneously. We investigated macroinvertebrate assemblages along gradients of human disturbance and morphometric characteristics in five lakes connected by the same stream. We aimed to assess the relative effects of environmental gradients on macroinvertebrate assemblages and to investigate whether water quality effects on the assemblages were correlated with buffer land use. There were significant differences in macroinvertebrate community compositions among lakes, and our results indicated that oligochaetes (mainly Limnodrilus) and insects (mainly Chironomus) contributed highly to the differences. We used redundancy analysis with variation partitioning to quantify the independent and combined anthropogenic effects of water quality and land use gradients on the macroinvertebrate community. The independent effect of water quality was responsible for 17% of the total variance in macroinvertebrate community composition, the independent effect of buffer land use accounted for 6% of variation, and the combined variation between land use change and water quality accounted for 12%. Our study indicated that both the independent effects of land use and within‐lake water quality can explain the influence in macroinvertebrate assemblages, with significant interactions between the two. This is rather important to notice that changes in buffer land use generally may alter nutrient inputs and thus severely affect abiotic conditions encountered by macroinvertebrate. Our study demonstrates that considering buffer zone effects explicitly may be significant in the selection and application of conservation and management strategies., Our study indicated that both the independent effects of land use and within‐lake water quality can explain the influence in macroinvertebrate assemblages, with significant interactions between the two. This is rather important to notice that changes in buffer land use generally may alter nutrient inputs and thus severely affect abiotic conditions encountered by macroinvertebrate.

Since 1980s, the weakening of the transportation function of the Grand Canal and rapid urbanisation have generated significant changes in the spatial pattern of rural settlements along the Grand Canal. Analysing the changing characteristics of this spatial pattern, and exploring the natural, social, and economic factors influencing these changes are key to understanding the regional spatial structure and development law, and grasping the degree of influence of these factors. This study selected approximately 13,000 rural settlements in 27 county-level units in the Shandong section of the Grand Canal, from 1980 to 2018, as the research object. The Grand Canal's distance buffer zone is divided into canal-side, near-canal, far-canal, and further-canal settlements. The correlation model with the canal is constructed through the controlled experiment. The distribution, scale, and form of the settlement are analysed quantitatively by applying the change of gravity centre model (CGC), average nearest neighbour analysis (ANN), landscape metrics (LM), and other methods. The quantitative analysis of geographic detectors in spatial pattern differentiation factors shows the relative importance and interaction within them. This study indicates that the spatial distribution shows ‘large dispersion and small concentration’ and ‘small-scale agglomeration’ characteristics. The larger the scale of the settlement expands, the more the number of settlements decreases. The closer the settlement nears the river, the more complex the shape clusters. The total output value of agriculture, forestry, animal husbandry, fisheries, the total power of agricultural machinery, and the effective irrigation area are the main influencing factors. The grain area and the per capita disposable income of rural residents are the main auxiliary influencing factors.

The primary tool used currently for preventing pesticide drift from entering streams is a no-spray buffer zone. Riparian hedgerows may provide an additional option; however, quantitative information on their effectiveness is limited. To quantify the potential benefit of riparian hedgerows for drift reduction, aerial malathion {diethyl 2-[(dimethoxyphosphorothioyl)sulfanyl]butanedioate} applications on blueberry ( L.) farms with fields adjacent to streams or ditches were monitored. Drift from fields with extensive dense woody riparian vegetation was compared with drift from fields with no dense woody riparian vegetation. Overall, total instream malathion deposition was 96.1% lower at vegetated sites compared with nonvegetated sites. Univariable models identified six variables that were significantly related to decreasing instream total malathion deposition: increasing bank canopy cover, increasing average site canopy cover, increasing canopy angle, increasing the distance between the field edge and vegetation edge, increasing the distance between the field edge and center of stream, and decreasing bank slope. For the variables most feasible for landowners to alter, the following increases could result, on average, in a 26% decrease in the total instream malathion deposition: bank canopy cover (7%), distance between field and vegetation (0.3 m), and distance between field and center of stream (0.9 m). No-spray buffer sizes needed for significant deposition reductions may be large, but for nonvegetated or minimally vegetated streams similar to those studied here, increasing bank canopy cover may give comparable advantages while allowing the use of the entire field area and conferring additional ecosystem benefits such as shading streams and improving habitat.

Buffer zones, established between agricultural fields and water bodies, are widely used as a measure to reduce N in surface runoff and groundwater. However, the literature indicates inconsistent results on the N removal efficiency of buffer zones between studies. We performed a weighed meta-analysis on the buffer zone effects on NO-N and total N in surface runoff and groundwater by summarizing 46 studies published between 1980 and 2017. The overall effects of buffer zones were a 33 (-48 to -17%, = 25) and 70% (-78 to -62%, = 38) NO-N reduction in surface runoff and in groundwater, respectively, compared with controls with no buffer zone. In addition, buffer zones reduced the total N in surface runoff by 57% (-68 to -43%, = 16). The effects of buffer zones on N retention were consistent across continents and in different climates. Nitrogen retention increased with increasing initial N concentrations discharged from the source of pollution. According to a meta-regression, the N removal efficiency in surface runoff decreased in consort with increasing buffer zone age. Otherwise, the meta-analysis revealed no effects of buffer zone characteristics such as the width or species number (for grass buffer zones) on the N retention in surface runoff and groundwater. Unlike groundwater quality, which responded equally well regardless of the source of pollution, buffer zone type, or buffer zone age, surface water quality is more sensitive, and it might not be satisfactorily improved by tree buffer zones or aged buffer zones, or when the source of pollution originates from grass production fields.

At the request of the European Commission, EFSA prepared these specific guidelines to guide the surveyor through the design of statistically sound and risk-based surveys for Phyllosticta citricarpa, integrating the key biological information. Based on examples, three different survey designs are simulated:(i) detection surveys to substantiate pest freedom, (ii) delimiting surveys to determine the boundaries of an infested zone, and (iii) buffer zone surveys to monitor a zone ensuring pest detection at low levels of prevalence.The first step of the survey design consists of setting the goals of the survey, characterising the host plant population and the methods used to identify the pest. All survey parameters are quantified taking into accountthe importance of the related assumptions. The more accurateand robust the information used for selecting and estimating the survey parameters, the more robust the conclusions of the survey will be. The second step of the survey design consists of the sample size (i.e. number of trees)calculation using the survey parameters as inputs of the proposed statistical tool (EFSA RiBESS+).The last step of the survey design is the allocation of the samples in the survey area which depends on the information available on the target population and risk factors. The robustness of the conclusions of surveys designed using the proposed approaches strongly depends on the survey preparation. The methodology proposed allows surveys to be compared across time and space, thus contributing to the harmonisation of the P.citricarpasurveys across the EU. The extremely flexible approach allows the surveys to be tailored to each specific situation in the Member States, taking into account the citrus tree distribution and available resources. The success of a good survey design relies on the technical aspects of the survey preparation and on the involvement of the risk managers.

Questions How do landscape changes along edges of protected areas affect forest interiors and stand development? What are the locations, spatial extents and magnitudes of these effects? Location The 8500-ha Sylvania Wilderness Area, Michigan's Upper Peninsula, USA. Methods We conducted vegetation surveys in 202 plots in ten transects crossing the Sylvania Wilderness border in 2013 and 2014. We recorded characteristics of forest structure, trees, shrubs, saplings, seedlings and herbaceous species. We constructed GLMM to estimate the location, spatial extent and magnitude of change of edge effects on Sylvania with a range of possible edge effect locations and widths of effect. We selected best-fit models that minimized the AIC and applied likelihood ratio tests to assess the statistical significance of each edge effect. Results Overall, evidence of edge effects occurred up to 625 m into the Sylvania Wilderness, with most significant changes occurring within 400 m of the wilderness border. Wide zones of change occurred across the wilderness border, while zones of change farther from the edge tended to be narrower, suggesting that distinct environments are established beyond the transitional habitats surrounding the border region. Canopy-level and understorey-level variables exhibited the largest magnitudes and steepest gradients of change, indicating these communities are strongly influenced by edge effects in this forest system. Canopy-level heterogeneity also increased approaching the internal core area of Sylvania. Conclusions In this case study, we applied a linear change point model and found a minimum buffer zone of 400 m to mitigate edge effects in an old-growth temperate mixed forest. Regionally, land managers could implement this buffer to existing edges of protected areas or negotiate this buffer zone in land acquisitions. A more stringent buffer zone of 625 m internal and 250 m external to old-growth forests would be ideal. This application of change point analysis provides a simple, efficient method to establish effective buffer zones and to identify functional groups or ecosystem attributes for which edge effects are of greatest conservation concern. We recommend modifying our open-source change point package to estimate local edge effects that take into account regional characteristics.

Terrapins are integral to many freshwater ecosystems, yet are imperilled at a global scale. In Sri Lanka, terrapins are understudied; thus, much of their natural history and distribution status remain unknown. Such paucity of studies impedes conservation. In this study, 79 freshwater habitats located outside the protected area network of south-western Sri Lanka were surveyed to document current population densities and habitat use of two terrapin species: Indian black terrapin (Melanochelys trijuga thermalis) and flap-shelled terrapin (Lissemys ceylonensis). Local inhabitants were interviewed to assess human threats towards terrapins. Both species were recorded in low densities: 1–2 individuals ha−1. Indian black terrapin was found in half of the surveyed sites while flap-shelled terrapin occurred in one-third of the surveyed sites. Highly urbanized river basins had the lowest densities for both species while rural basins supported higher numbers. Basking was the predominant behaviour of both species and large woody debris and boulders were preferred as basking substrates, together with sparse-canopy aquatic habitats with intact marshlands. Overharvesting for meat was a major threat for terrapins. Most local inhabitants were unaware of legislation on terrapin conservation and the ecological importance of terrapins. Human threats such as pollution, modification of aquatic and wetland habitats, and loss of riparian forests were frequently observed in surveyed sites. Terrapin populations outside the protected area are at risk as evidenced by lower population densities and a multitude of human threats. A landscape-scale ecosystem-based conservation approach is recommended for Sri Lanka's terrapins with incorporation of lands with different management regimes (privately owned, municipality managed) into the protected area network. Current environmental legislation should be revised to support buffer zone delineation for aquatic habitats, wetland restoration, and landscape-scale connectivity.

Vigilance achieved at the group level, known as collective vigilance, can enhance the ability to assess threats and confer benefits to gregarious prey species. Examining the factors that influence collective vigilance and exploring how individual vigilance is organized at the group level can help to understand how prey groups respond to potential threats. We quantified collective vigilance and determined its temporal pattern in a natural wintering population of the hooded crane Grus monacha in the Shengjin Lake reserve in China. We examined the role of flock size and anthropogenic disturbances in the human-dominated landscape on collective vigilance and level of synchronization. The proportion of time during which at least one individual scanned the surroundings (collective vigilance) increased with flock size and was higher in the more disturbed buffer zone of the lake. Synchronization of vigilance occurred more frequently in the smaller flocks but was not related to the risk of disturbance. Synchronization implies that individuals tend to monitor and copy the vigilance of neighbors. In the degraded wetlands, the wintering hooded crane benefits from foraging in groups and synchronizing their vigilance in response to human disturbances.

Asylum systems in the Western Balkans are one of the many results of the externalization of European Union border controls. Regardless of the hopes that the EU might have for these systems to function as a “buffer zone”, there is a need to be realistic about the actual effect that these systems can have. There are a number of gaps showing that the countries in the region are neither willing nor able to process the number of asylum applications that could potentially be lodged by all the persons transiting the region today. These gaps include the lack of capacity to identify and register asylum seekers and to process asylum applications, the failure to conduct refugee status determination procedures in line with basic legal standards, the lack of return procedures and the inability to develop all the necessary systems (such as detention and return) in parallel.

The grass buffer zone (GBZ) is commonly used a best management practice for the control of agricultural pollutants. However, the sorption and removal mechanisms of pollutants within GBZ have not been clearly identified. We studied changes in soluble reactive phosphorus (SRP) from dairy house wastewater in the GBZ, after the wastewater application to the field was stopped. The results showed that Morgan soil test P levels in the saturated area were low compared to the soils in the relatively drier area. High SRP concentrations >4 mg/L were observed in monitoring wells near the discharge points and in the downslope area. The SRP concentration as high as 9.4 mg/L near the discharge point in the saturated area was caused by the highly reduced soil conditions, while the SRP concentration in the downslope area was likely due to the topographic convergence. The SRP concentrations for the wells in the GBZ decreased

Numerous examples exist of successful mammalian invasive alien species (IAS) eradications from small islands (

Innovative conservation tools are greatly needed to reduce livelihood losses and wildlife declines resulting from human–carnivore conflict. Spatial risk modeling is an emerging method for assessing the spatial patterns of predator–prey interactions, with applications for mitigating carnivore attacks on livestock. Large carnivores that ambush prey attack and kill over small areas, requiring models at fine spatial grains to predict livestock depredation hot spots. To detect the best resolution for predicting where carnivores access livestock, we examined the spatial attributes associated with livestock killed by tigers in Kanha Tiger Reserve, India, using risk models generated at 20, 100, and 200-m spatial grains. We analyzed land-use, human presence, and vegetation structure variables at 138 kill sites and 439 random sites to identify key landscape attributes where livestock were vulnerable to tigers. Land-use and human presence variables contributed strongly to predation risk models, with most variables showing high relative importance (≥0.85) at all spatial grains. The risk of a tiger killing livestock increased near dense forests and near the boundary of the park core zone where human presence is restricted. Risk was nonlinearly related to human infrastructure and open vegetation, with the greatest risk occurring 1.2 km from roads, 1.1 km from villages, and 8.0 km from scrubland. Kill sites were characterized by denser, patchier, and more complex vegetation with lower visibility than random sites. Risk maps revealed high-risk hot spots inside of the core zone boundary and in several patches in the human-dominated buffer zone. Validation against known kills revealed predictive accuracy for only the 20 m model, the resolution best representing the kill stage of hunting for large carnivores that ambush prey, like the tiger. Results demonstrate that risk models developed at fine spatial grains can offer accurate guidance on landscape attributes livestock should avoid to minimize human–carnivore conflict.

Wetlands in farmland are at risk of contamination by fertilizers and pesticides. One recommendation for reducing wetland contamination is to maintain a buffer of contiguous uncropped land around the wetland (a wetland buffer). Many agricultural water protection policies around the world recommend 5 to 50‐m wide uncropped buffers around water bodies, but it is unclear how large wetland buffers must be to effectively protect against these chemicals. In addition, it is unclear whether wetland buffers have similar—or stronger—effects on fertilizer and pesticide contamination than reducing the amount of cropped land within the larger landscape context around wetlands. Our study, conducted across 37 wetlands in eastern Ontario, Canada, addressed the following questions: (1) Does increasing buffer width, or increasing the amount of contiguous uncropped land within recommended buffer width guidelines, reduce nutrient and pesticide levels in agricultural wetlands? (2) Does increasing uncropped land cover in the broader landscape reduce nutrient and pesticide levels in agricultural wetlands? and (3) What is the relative importance of buffer size and landscape‐scale uncropped cover for reducing nutrient and pesticide levels in agricultural wetlands? A rigorous site selection process was employed to minimize the correlation between buffer size and landscape‐scale uncropped cover, minimize spatial gradients in these predictor variables, and minimize variation in potentially confounding variables. We obtained nutrient and pesticide data by collecting water samples from each wetland under similar weather conditions in June–July 2015. Nitrate concentrations were measured using ion chromatography, and atrazine and neonicotinoid (pesticide) concentrations using a combination of high‐performance liquid chromatography and mass spectrometry. We found that nitrate, atrazine, and neonicotinoid concentrations in study wetlands were unaffected by wetland buffer size. However, concentrations of each chemical decreased with uncropped land cover in the surrounding 150 to 300‐m radius landscapes. To effectively protect water in agricultural wetlands from contamination by nitrate‐based fertilizers and atrazine or neonicotinoid pesticides, we recommend either increasing the policy‐recommended width of wetland buffers to at least 150 m, or abandoning the buffer paradigm in favor of landscape‐scale conservation.

Drawing results from multi-scale studies, this paper addresses the important coexistence between the Chitwan National Park and buffer-zone farmers’ communities in the East Rapti River basin of Nepal. The relationship between the two is discussed using results of land use change (1978–2010) and water availability analysis (1976–2010). At basin level, though there are indications of losses of the government forest, the utilizable outflow of water in the river is still abundant because the process of depletion of water is very low. Scaling down to local level, irrigation systems originating in the river were evaluated and farmers interviewed across locations. There were statistical differences in irrigation system performance affecting water availability for crop production in the buffer zone. Because irrigation plays a disproportionately greater role in farm income and economic water scarcity could be removed, improvement in access to irrigation could effectively help improve food sufficiency and reduce income disparity in this basin. In the forest of the national park, encroachment seems to be low but frequencies of rhino poaching and timber pilferage have remained relatively high. As the buffer zone is the gateway to the park, and subsistence farm families live on the fringes of the park, helping irrigation development would strengthen farmers’ cooperation in enhancing resource conservation of the park. Copyright © 2013 John Wiley & Sons, Ltd. RESUME Base sur les resultats de plusieurs etudes a differentes echelles, ce document traite de l'importance de la coexistence entre le parc national de Chitwan et les communautes d'agriculteurs de la zone tampon, dans le bassin de la riviere Rapti a l'est du Nepal. La relation entre les deux est discutee a partir des resultats de changements de l'utilisation des terres (1978–2010) et de l'analyse de la disponibilite en eau (1976–2010). Au niveau du bassin, bien qu'il y ait des signes de deprise des forets d'etat, le prelevement potentiel d'eau dans la riviere est encore important, car le processus d'epuisement de l'eau est tres faible. Au niveau local, les systemes d'irrigation alimentes par la riviere ont ete evalues, et les agriculteurs ont ete interroges par zone geographique. Il y avait des differences statistiques dans les performances des systemes d'irrigation qui affectent la disponibilite de l'eau pour la production agricole dans la zone tampon. Parce que l'irrigation joue un role proportionnellement plus fort dans le revenu agricole, l'irrigation pourrait supprimer la penurie economique liee au manque d'eau. L'amelioration de l'acces a l'irrigation pourrait contribuer efficacement a ameliorer l'autosuffisance alimentaire et a reduire la disparite des revenus dans ce bassin. Dans la foret du parc national, l'empietement semble faible, mais les frequences de braconnage de rhinoceros et de vols de bois ont garde un niveau relativement eleve. Comme la zone tampon est la porte d'entree du parc, et que l'agriculture vivriere retient les familles d'agriculteurs dans la peripherie du parc, aider le developpement de l'irrigation permettrait de renforcer la cooperation des agriculteurs dans la conservation des ressources et l'amelioration du parc. Copyright © 2013 John Wiley & Sons, Ltd.

This article focuses on the practices of resistance organised by a group of Cypriot activists in the Buffer Zone that separates the island of Cyprus into two sovereign entities, the Republic of Cyprus and the Turkish Republic of Northern Cyprus. Being a space where the territorialising norm of these two entities is suspended, the Buffer Zone constitutes a space of exception. By drawing on a post-colonial reading of this Agambenian notion, the article analyses the specifics of a 'terrain of resistance' deliberately located in the exception. It argues that rather than being a dispossessing condition, the exception might actually be empowering, because it offers the activists a terrain from which to contest the very norm that they are escaping. The article also critically reflects on the limits of this tactic, by revealing how power might adopt counter-exceptions aimed at reterritorialising exceptional spaces that no longer work to its advantage. The OccupyBufferZone (OBZ) experience also allows for a series of theoretical considerations that can illuminate further the notion of 'terrain of resistance'.

The authors were asked to assist a utility with a risk man-agement decision. Specifically, the utility was consideringwhether they should maintain or decommission an 800,000gallon propane storage sphere. The 30-year old sphere wasthe fuel storage vessel for a propane standby system. One oftheir major concerns was the shrinking buffer zone aroundtheir facility. Although the facility was originally located in aremote rural area, residential development had begun toencroach upon the facility’s buffer zone.The original analysis was based on a consideration of theoffsite consequences for a worst-case scenario. This was doneat the request of the client as it reflected their degree of riskacceptance. The consequences of two hazard scenarios wereanalyzed: an unconfined vapor cloud explosion and a Boil-ing Liquid Expanding Vapor Explosion (BLEVE). To supportthis analysis, the mechanical integrity of the sphere was eval-uated deterministically by considering the pressure vesseldesign documents, the limited nondestructive test and evalu-ation data available, and published data on typical corro-sion rates. Additional factors incorporated into the analysiswere the capabilities of the existing fire protection system, thefacility security system, and the propane unloading stationfor tank car deliveries. Finally, the economics of maintainingthe sphere versus decommissioning it were explored. Ulti-mately, the utility decided to decommission the sphere.In this article, we conduct a retrospective study using arisk-based approach. We identify a set of hazard scenariosfor the propane storage sphere, calculate the leak frequencyfor each scenario, compute the associated source term, andevaluate the consequences. The results are compared with theoriginal consequence analysis and other published hazardstudies. The implications for risk management are discussed.

We propose a new optimization model that captures the spatial dynamics of invaders by a cellular automaton model and finds the optimal solution to control its spread within a 0–1 integer programming framework. The model seeks a solution by minimizing the total costs to implement treatments for preventing the spread and damage caused by invaders’ colonization. By incorporating a cellular automaton model governed by state- and distance-dependent probability rule of colonization, the model is transformed into a linear model, so that a 0–1 integer programming formulation is used to evaluate and compare an optimal allocation of treatments on colonized and uncolonized areas. The study uses a hypothetical map to show that treatments on colonized cells are more effective when implemented at the front line of the invaders, while treatments on uncolonized areas are effective when conducted with some distance or buffer zone away from the front line. These buffer zones are likely to be colonized regardless of treatment. Under annual budget limits, treatments on colonized cells are implemented first. With heterogeneity in the invaders’ dynamics, the proposed optimization model provides an optimal allocation of treatments much different from the solution with homogeneous environment. However, treatment at the front line of the invading species is always recommended.

Tarmi S, Helenius J & Hyvonen T (2011). The potential of cutting regimes to control problem weeds and enhance species diversity in an arable field margin buffer strip. Weed Research51, 641–649. Summary Buffer zones in arable land could promote biodiversity of agricultural areas. These are most often established with sown seed mixtures of grasses and herb species. We studied the impact of cutting management and the role of the seedbank on plant species diversity of a sown buffer strip. Two main hypotheses H1 were tested in this study: (i) sward cutting and removal have positive effects on plant species diversity in a buffer zone adjacent to a cultivated field and (ii) the buffer zone soil seedbank and adjacent grassland act as a species source for the managed buffer zone. After 5 years of management, the number of species was significantly higher and the litter coverage significantly lower in plots mown yearly with cuttings removed than in mown plots with the cuttings left or an uncut control. The abundance of Elymus repens was not affected by the cutting management. To reduce E. repens probably needs cutting more frequently than once per year. Cutting management did not reduce easily-soluble phosphorus in soils. For species colonisation, adjacent grassland played a more important role than the soil seedbank. We conclude that, in this study, the reduced litter cover, together with adjacent sources of species, resulted in the gradual increase in species diversity in the species-poor buffer habitat. This study took place in a single location and similar studies in additional locations would be helpful in assessing the generality of our results. On the evidence of this study, the contract periods of agri-environmental schemes should be longer than 5 years to ensure cutting does result in positive benefits for the management of biodiversity.

D uring the past few decades, lawmakers have devoted increasing attention to policies aimed at managing sex offenders released to the community. Indeed, since 1994, all 50 states have enacted at least two pieces of legislation specific to sex offenders; at the minimum, each of the 50 states has established a sex offender registry and a community notification system in compliance with the Jacob Wetterling Act of 1994 and Megan’s Law of 1996, respectively (CSOM, 2008). Since this time, states have passed several other laws targeted at sex offenders. For example, some states require sex offenders to carry special identification cards, whereas other states have the authority to impose chemical castration (Mancini, 2009). Among the newest wave of sex offender policies to sweep the United States are residence restrictions. A recent analysis revealed that since 1999 more than half of all states have enacted a residence restriction law (Mancini, 2009). Residence restrictions come in different shapes (i.e., different “hot-spot” locations) and sizes (i.e., different “buffer zones”). A hot spot is a specific location that is restricted for sex offenders, and it typically is defined as a park, playground, daycare center, or school. A buffer zone is the exclusion perimeter that is established around identified hot spots. For example, a buffer zone of 500 feet means that sex offenders cannot reside within 500 feet of hot spots. Buffer zones can range from 500 feet to more than 5,000 feet depending on the state of interest (Mancini, 2009; Meloy, Miller, and Curtis, 2008). Despite variation in the scope of hot spots that can be included and the size of buffer zones that can be used, all residence restriction laws operate on the following underlying rationale: keeping a sex offender away from areas where children are

Available studies do not allow comparison and quantification of the effects of biological geotextiles on runoff and water erosion rates under different agro-environmental conditions. Hence, this paper addresses this issue by comparing runoff and soil loss data obtained from field experiments (using different types of biological geotextiles) conducted in the United Kingdom, Hungary, South Africa, China, Thailand and Vietnam. Palm leaf mats (Borassus and Buriti mats) were used in the European countries. In the UK, Borassus mats were used as whole plot cover (area coverage ∼76 per cent; termed Borassus completely covered to differentiate from the Borassus buffer strip plots) and as buffer zones (area coverage ∼10 per cent), whereas Buriti mats were used only as buffer zones (area coverage ∼10 per cent). Only Lala mats were used in South Africa. Elsewhere (China, Thailand and Vietnam) biological geotextiles were constructed using other indigenous local materials, such as bamboo, rice straw and maize stalks. Biological geotextiles were used on bare plots in South Africa and the European countries. In the UK, plots were maintained bare by need based herbicide spraying. However, in South Asia, different crops were grown on the geotextile-covered plots. Results suggest that biological geotextiles were very effective for soil erosion control in all locations and the effectiveness for decreasing soil erosion rates by water was in the range of ∼67–99 per cent. The effectiveness of biological geotextiles in reducing runoff volume was in the range of ∼26–81 per cent. In the UK, total runoff and soil loss (during 8 January 2007–6 May 2008; total precipitation = 1145.8 mm) from the Borassus (one metre wide) buffer zone plots (cover percentage ∼7.6 per cent) were, respectively, ∼81 and ∼93 per cent less than bare plots. In Hungary and China, plots with ∼38 and 22 per cent geotextile-cover, respectively, had ∼88 and 96 per cent less soil loss, than bare plots. In most months with low precipitation (depth) in Hungary and the UK, runoff volume was greater from plots with geotextile-cover than from bare soils. However, complete data sets indicate that in the UK and Hungary, runoff reduction by different treatments over bare plots ranged between ∼26 and 81 per cent. Results from the UK showed that plots with buffer strips of Borassus and Buriti mats had similar effects in reducing soil losses as completely covered plots of the Borassus mats. Thus, foreseeing biological geotextile-cover on vulnerable segments of the landscape is highly effective for soil erosion control. Copyright © 2011 John Wiley & Sons, Ltd.

Limitation of disturbing activities around the breeding areas of protected species is not always possible, if these activities are economically important and have, in addition, positive effects on protecting the habitats of those protected species. Searching for optimal solutions making commercial exploitation of natural resources compatible with biodiversity conservation is thus of concern to managers and policy makers. This is the case of the cinereous vulture Aegypius monachus, breeding primarily in cork-oak woodland, and cork exploitation, a traditional socio-economic activity carried out in several Mediterranean countries, and critical for the maintenance of this important habitat. We studied the effects of this anthropogenic activity on the behaviour and breeding success of breeding cinereous vultures in Spain. For the adults, the probability of nest abandonment was dependent on the distance of workers from the nest and the level of noise; activities within 500 m from the nest were likely to cause abandonment of the nest by adults, if the level of noise was intermediate or loud. Neither the size of the working group nor the use of machines per se, had any effect on the probability of nest abandonment. Pairs in an area of the colony exposed to intrusive anthropogenic activity had 20% lower breeding success than those in the same colony that were not exposed to these disturbances. If the application of buffer zones of 500 m is not possible (as is likely given the economic losses involved), several alternatives are recommended based on our results to minimize the impact of these activities, in particular to diminish the noise level of cork extraction activities. Observational studies like this help understanding the magnitude of the problem and finding alternative solutions for harmonizing conservation and economic development.

DeWalle, David R., 2010. Modeling Stream Shade: Riparian Buffer Height and Density as Important as Buffer Width. Journal of the American Water Resources Association (JAWRA) 46(2):323-333. DOI: 10.1111/j.1752-1688.2010.00423.x Abstract: A theoretical model was developed to explore impacts of varying buffer zone characteristics on shading of small streams using a path-length form of Beer’s law to represent the transmission of direct beam solar radiation through vegetation. Impacts of varying buffer zone height, width, and radiation extinction coefficients (surrogate for buffer density) on shading were determined for E-W and N-S stream azimuths in infinitely long stream sections at 40°N on the summer solstice. Increases in buffer width produced little additional shading beyond buffer widths of 6-7 m for E-W streams due to shifts in solar beam pathway from the sides to the tops of the buffers. Buffers on the north bank of E-W streams produced 30% of daily shade, while the south-bank buffer produced 70% of total daily shade. For N-S streams an optimum buffer width was less-clearly defined, but a buffer width of about 18-20 m produced about 85-90% of total predicted shade. The model results supported past field studies showing buffer widths of 9-11 m were sufficient for stream temperature control. Regardless of stream azimuth, increases in buffer height and extinction coefficient (buffer density) were found to substantially increase shading up to the maximum tree height and stand density likely encountered in the field. Model results suggest that at least 80% shade on small streams up to 6-m wide can be achieved in mid-latitudes with relatively narrow 12-m wide buffers, regardless of stream azimuth, as long as buffers are tall (≈30 m) and dense (leaf area index ≈6). Although wide buffers may be preferred to provide other benefits, results suggest that increasing buffer widths beyond about 12 m will have a limited effect on stream shade at mid-latitudes and that greater emphasis should be placed on the creation of dense, tall buffers to maximize stream shading.

To inform the development of alternative livelihoods, the women’s traditional alok fishery in the Campo-Ma’an National Park and buffer zone of southern Cameroon were studied over 15 months. Participatory rural appraisal was used to characterise livelihood strategies among 45 households. Thirty-three cultured crops, nine farmed animal species and 65 non-timber forest products, including 31 bushmeat species are cultivated in, or harvested from, the forest. Transport is a major impediment to commercial trade of all local products. In 16 alok fishing events, average weight of fish harvested was 5.14 kg per 280 m of stream distributed among an average of 23 fishers for a return of 220 g person−1 or 40 g fish h−1 over 5 h of work. Fish and crustacean standing stock was 25 g per linear metre or 167 t when extrapolated to the zone. Implications for rainforest livelihoods in light of the Millennium Development Goals are discussed.

Conservation of ecological processes and biodiversity may require development of a conservation system consisting of protected "cores" surrounded by "buffer zones" that effectively expand and connect the cores. Nevertheless, residential development near protected areas may threaten de facto protected areas and hinder development of an official conservation system in the United States. We identified potential conservation cores based on existing protected areas, and using a spatially explicit model of housing densities, we quantified how residential development has altered the structural context around cores nationally from 1970 to 2000 and forecasted changes from 2000 to 2030. We found that residential housing development has likely occurred preferentially near some cores, and if encroachment near cores continues at projected rates, the amount of buffer zone will have been reduced by a total of 12% by 2030, with much of this change occurring directly at core edges. Furthermore, development will have reduced the average connectedness (valence) of cores by 6% from 1970 to 2030. Although patterns of encroachment roughly increased west to east, our results painted a more complex picture of the difficulties that would be faced if establishment of an official conservation system was ever attempted. At a minimum, prioritizing future conservation action must consider adjacent land uses, and a key conservation strategy will be to work cooperatively across land-ownership boundaries, particularly for smaller protected areas, which will tend to dominate future conservation activities.

Fishing activities worldwide have dramatically affected marine fish stocks and ecosystems. Marine protected areas (MPAs) with no-take zones may enhance fisheries, but empirical evidence of this is scant. We conducted a 4-year survey of fish catches around and within an MPA that was previously fully closed to fishing and then partially reopened under regulated comanaged fishing. In collaboration with the fishers and the MPA authority, we set the fishing effort and selected the gear to limit fishing impact on key fish predators, juvenile fish stage, and benthic communities and habitats. Within an adaptive comanagement framework, fishers agreed to reduce fishing effort if symptoms of overfishing were detected. We analyzed the temporal trends of catch per unit of effort (CPUE) of the whole species assemblages and CPUE of the four most valuable and frequent species observed inside the opened buffer zone and outside the MPA investigated. After the comanaged opening, CPUE first declined and then stabilized at levels more than twice that of catches obtained outside the MPA. Our results suggest that working closely with fishers can result in greater fisheries catches. Partial protection of coastal areas together with adaptive comanagement involving fishers, scientists, and managers can effectively achieve conservation and fishery management goals and benefit fishing communities and alleviate overfishing.

Europe is attempting to contain or, in some regions, to eradicate the invading and maize destroying western corn rootworm (WCR). Eradication and containment measures include crop rotation and insecticide treatments within different types of buffer zones surrounding new introduction points. However, quantitative estimates of the relationship between the probability of adult dispersal and distance from an introduction point have not been used to determine the width of buffer zones. We address this by fitting dispersal models of the negative exponential and negative power law families in logarithmic and non-logarithmic form to recapture data from nine mark-release-recapture experiments of marked WCR adults from habitats as typically found in the vicinity of airports in southern Hungary in 2003 and 2004. After each release of 4000-6300 marked WCR, recaptures were recorded three times using non-baited yellow sticky traps at 30-305 m from the release point and sex pheromone-baited transparent sticky traps placed at 500-3500 m. Both the negative exponential and negative power law models in non-log form presented the best overall fit to the numbers of recaptured adults (1% recapture rate). The negative exponential model in log form presented the best fit to the data in the tail. The models suggested that half of the dispersing WCR adults travelling along a given bearing will have travelled between 117 and 425 m and 1% of the adults between 775 and 8250 m after 1 day. An individual-based model of dispersal and mortality over a generation of WCR adults indicated that 9.7-45.3% of the adults would escape a focus zone (where maize is only grown once in 3 consecutive years) of 1 km radius and 0.6―21% a safety zone (where maize is only grown once in 2 consecutive years) of 5 km radius and consequently current European Commission (EC) measures are inadequate for the eradication of WCR in Europe. Although buffer zones large enough to allow eradication would be economically unpalatable, an increase of the minimum width of the focus zone from 1 to 5 km and the safety zone from 5 to 50 km would improve the management of local dispersal.

Technical interventions have not always led to expected outcomes when attempting to achieve a balanced growth between natural resource development and food production, particularly in the context of Third World countries. In Royal Chitwan National Park (RCNP) buffer zone, Nepal, farmers' perceptions were used to evaluate how irrigation resource development and the method of water sharing have increased household food security and reduced pressure on natural resources of the park. The findings indicate that with some variations between communities, increased water availability and reliability through irrigation development have improved crop diversity, cropping intensity, food sufficiency, and economic return to farmers. Community attributes such as leadership and dynamics were, among others, the decisive factors that determined the degree of success of the government development intervention programme in the buffer zone. Small landholders and low-income groups in dry areas perceived that they received greater benefits from micro-groundwater pumping schemes. However, many rural poor inhabitants in the area still lack access to these resource opportunities. We observed that Park and People, a government programme, successfully improved public relations and helped create awareness in this buffer zone. However, grievances persist among other water user groups in the upstream part of the Rapti River where a water-sharing mechanism needs to be defined between water user associations for crop production and maintenance of biodiversity of the national park. Copyright © 2008 John Wiley & Sons, Ltd.

In recent years, there has been growing recognition of the importance of riparian buffers between agricultural fields and waterbodies. Riparian buffers play an important role in mitigating the impacts of land use activities on water quality and aquatic ecosystems. However, evaluating the effectiveness of riparian buffer systems on a watershed scale is complex, and watershed models have limited capabilities for simulating riparian buffer processes. Thus, the overall objective of this paper is to develop an understanding of riparian buffer processes towards water quality modelling/monitoring and nonpoint source pollution assessment. The paper provides a thorough review of relevant literature on the performance of vegetative buffers on sediment reduction. It was found that although sediment trapping capacities are site- and vegetation-specific, and many factors influence the sediment trapping efficiency, the width of a buffer is important in filtering agricultural runoff and wider buffers tended to trap more sediment. Sediment trapping efficiency is also affected by slope, but the overall relationship is not consistent among studies. Overall, sediment trapping efficiency did not vary by vegetation type and grass buffers and forest buffers have roughly the same sediment trapping efficiency. This analysis can be used as the basis for planning future studies on watershed scale simulation of riparian buffer systems, design of effective riparian buffers for nonpoint source pollution control or water quality restoration and design of riparian buffer monitoring programs in watersheds. Published in 2009 by John Wiley & Sons, Ltd.

Tsunami intervention has been an extraordinary and unprecedented relief and recovery operation. This article underlines the complexities posed by shelter and housing intervention in post-tsunami Sri Lanka, revealing a pragmatic, reductionist approach to shelter and housing reconstruction in a contested and fragmented environment. Competition, housing anxiety and buffer zone implementation have resulted in compulsory villagisation inland, stirring feelings of discrimination and tension, and becoming major obstacles to equitable rebuilding of houses and livelihoods. A new tsunami geography has been imposed on an already vulnerable conflict-based geography, in which shelter has been conceived as a mono-dimensional artefact. An analysis of the process and outcomes of temporary and permanent post-tsunami housing programmes yields information about the extent to which shelter policies and programmes serve not only physical needs but 'higher order' objectives for a comprehensive and sustainable recovery plan.

In developing countries, participatory land-use planning is seen as a panacea to mitigate land-use conflicts and enhance land productivity. This assumption has not been thoroughly tested in wildlife corridors. Three villages were selected for this study. Several methods were used to provide indication of the performance of the plans against their stated objectives of mitigating conflicts and conserving wildlife corridors. Three hundred and fifty-eight households and eight park and extension workers were interviewed. In addition, focus group discussion with the nomadic Barabeig, field assessment and review of land-use plan/general management plan reports were carried out. Results reveal that land-use plans failed to achieve their set objectives. For example, 75% of the households held this view. Major causes of failure were insufficient participation by stakeholders in the planning process, lack of robust, transparent and accountable implementation strategies, inadequacy of qualified staff and lack of ‘holistic approach’ to the planning process. Taking these findings into account, an improved buffer zone land-use planning framework is suggested. For the framework to enhance both conservation and development and to enable policies and legislation, equitable benefit sharing and conservation education, initiation of compensation schemes for depredation caused by wild animals and intensification of patrols are required.

This article formulates and tests set covering and related models with spatial characteristics for selecting sites that provide habitat for species that are identified as “critical” (e.g., typically threatened, endangered, or rare), thereby enhancing their persistence. The first two models presented require the creation of a core area for each critical species and a buffer zone surrounding the core, with and without being constrained to include at least one representation of each and every common (i.e., noncritical) species. The final model aims at minimizing costs of protecting predetermined numbers of common species while all critical species remain covered and buffered. These models are implemented for occurrence data of terrestrial mammals in Oregon. They enable, among other things, a comparison between the budgetary impacts of reserve networks with and without buffering rings for critical species, and a determination of the marginal cost of common species protection.

Nonpoint source pollution, which contributes to contamination of surface waters, is difficult to control. Some pollutants, particularly nitrate (NO 3 - ), are predominantly transmitted through ground water. Riparian buffer zones have the potential to remove contaminants from ground water and reduce the amount of NO 3 - that enters surface water. This is a justification for setting aside vegetated buffer strips along waterways. Many riparian zone hydrologic models assume uniform ground-water flow through organic-rich soil under reducing conditions, leading to effective removal of ground-water NO 3 - prior to discharge into a stream. However, in a small first-order stream in the mid-Atlantic coastal plain, base-flow generation was highly variable (spatially and temporally). Average base-flow NO 3 - loads were greater in winter than summer, and higher during a wetter year than in dryer years. Specific sections of the stream consistently received greater amounts of high NO 3 - ground water than others. Areas within the riparian zone responsible for most of the NO 3 - exported from the watershed are termed "critical areas." Over this 5-year study, most of the NO 3 - exported during base flow originated from a critical area comprising less than 10% of the total riparian zone land area. Allocation of resources to address and improve mitigation function in critical areas should be a priority for continued riparian zone research.

Being able to identify riparian sites that function better for nitrate removal from groundwater is critical to using efficiently the riparian zones for water quality management. For this purpose, managers need a method that is quick, inexpensive, and accurate enough to enable effective management decisions. This study assesses the precision and accuracy of a simple method using three ground water wells and one measurement date for determining nitrate removal characteristics of riparian buffer zones. The method is a scaled-down version of a complex field research method that consists of a large network of wells and piezometers monitored monthly for over two years. Results using the simplified method were compared to those from the reference research method on a date-by-date basis on eight sites covering a wide range of hydrogeomorphic settings. The accuracy of the three-well, 1 day measurement method was relatively good for assessing nitrate concentration depletion across riparian zones, but poor for assessing the distance necessary to achieve a 90% nitrate removal and for estimating water and nitrate fluxes compared to the reference method. The simplified three-well method provides relatively better estimates of water and nitrate fluxes on sites where ground-water flow is parallel to the water table through homogeneous aquifer material, but such conditions may not be geographically widespread. Despite limited overall accuracy, some parameters that are estimated using the simplified method may be useful to water resource managers. Nitrate depletion information may be used to assess the adequacy of existing buffers to achieve nitrate concentration goals for runoff. Estimates of field nitrate runoff and buffer removal fluxes may be adequate for prioritizing management toward sites where riparian buffers are likely to have greater impact on stream water quality.

In this study, we investigated the attitude of local people towards the contribution of agroforestry practices to socio-economic development in the buffer zone area of Mt Elgon National Park, Uganda. Primary data were collected through formal household survey conducted during June–October 2004 with the use of questionnaires administered to 120 households selected randomly from Mutushet and Kortek Parishes. Data were analysed using chi-squared test and logistic regression model. The results support the hypothesis that the attitude of people towards agroforestry practices is independent of existence of collaborative forest management, ethnic group, sedentary farming experience and family size but depends on main occupation, education status, distance from park boundary, damage caused by wild animals, landholding size and total livestock units owned. Factors that significantly influenced adoption of agroforestry technologies were age of the household head, education status, extension contact, family labour force and gender. There is need to intensify extension programmes in those areas where the majority of people have negative attitude towards agroforestry practices.

Here, I examine overlapping resource use of forest and cultivated resources by villagers and tonkean macaques (Macaca tonkeana) in Lore Lindu National Park, Sulawesi, Indonesia. An integrative research design was employed, using methods from primatology and cultural anthropology, in conjunction with quantitative measurements of cacao crop loss. The results indicate that the current patterns of overlapping resource use may not be severely affecting the tonkean macaques or villagers in Lindu. The research does, however, point to possible future difficulty if cacao crop raiding by macaques increases, and as changing socioeconomic trends and loss of traditional folklore result in further modification of macaque habitat. Successful strategies to ameliorate human–macaque conflict may require efforts aimed at the adoption of alternative buffer zone crops that use shade-management systems, the deliberate protection of important macaque food species, and increasing local tolerance to crop raiding by exploring the role of macaques in forest regeneration.

Summary 1 There is an increasing awareness of the need to evaluate critically the effectiveness of environmental conservation measures, and to ensure that agri-environment policies are based on the best available scientific evidence. 2 A systematic review and meta-analysis investigated the impact of pesticide restriction in arable crop edges on naturally occurring terrestrial invertebrates. Twenty-three relevant experimental studies yielded 1094 pesticide contrasts. A standardized effect size (Hedges’g) could be calculated for 685 of these. 3 Empirical data were available for 12 broad types of pesticide manipulation in crop edges. The majority of the data concerned the exclusion or selective use of herbicides. No reliable information was available on the ecological consequences for naturally occurring arthropods of excluding fungicides or insecticides separately from crop edges. 4 Studies have focused on Carabidae, Heteroptera, Staphylinidae, Lepidoptera and grouped chick-food insects. Abundance of Heteroptera was up to 12·9 times higher where pesticide use was restricted. For other invertebrates, restricted use of pesticides generally either increased abundance or had no impact. Only two species exhibited a significant decrease in abundance. 5 Restricting pesticide use in crop edges in most cases did not significantly affect Carabidae. This might be an artefact of the sampling method, which predominantly involved pitfall trapping. 6 Generalization of the findings is hindered by ambiguous reporting in the primary studies. In most (20 out of 23) studies, the possibility of confounding between pesticide and fertilizer inputs could not be discounted. 7 Synthesis and applications. Meta-analysis confirms that restriction of pesticide inputs in crop edges benefits arthropod populations at the edges of arable fields. However, an assumption in risk assessment that such benefits extend to invertebrate populations in adjacent sprayed areas is not supported. Moreover, the generality of the effects within crop edges is limited mainly to herbicides. This review highlights a lack of information on the ecological consequences of excluding insecticides and fungicides from crop edges, and identifies a need to improve the clarity of reporting in agro-ecology studies.

This study evaluates the economic value of riparian buffers and open space in a suburban watershed through two nonmarket valuation methods. A contingent valuation survey was implemented in the Dardenne Creek watershed, a suburban watershed of the St. Louis metropolitan area in Missouri, to evaluate the residents' perceptions of and willingness to pay (WTP) for adopting riparian buffers and preserving farmland in a hypothetical real estate market. A hedonic pricing model based on actual sale prices of homes in the watershed was applied to estimate the market value of open space and other environmental conditions such as flood zone and stream proximity in the study area. The results showed that residents' WTP was consistent with the economic values of open space and proximity to streams embedded in existing home prices. Through a better understanding of residents' perceptions and values, riparian buffer and open space programs can be designed and promoted to achieve greater implementation success and environmental benefit.

In spatial analyses of causes or health effects of environmental pollutants, small units of analyses are usually preferred for internal environmental homogeneity reasons but can only be done when fine resolution data are available for most units. Objectives of this study were to determine which land use practices were spatially associated with ground water nitrate concentrations across Prince Edward Island (PEI), Canada, and which spatial aggregation is the preferred unit of analyses. Nitrate concentrations were determined for 4855 samples from private wells. Validated field-by-field land use data were available. Average nitrate concentration and percentage of area for the 14 major land use categories in PEI were determined for each of three spatial aggregations: watersheds based on topography and hydrology; freeform polygon boundaries based on similar neighboring nitrate concentrations; and 500-m buffer zones around each well. Results showed that the percentages of potato, grain, and hay coverage were positive predictors of ground water nitrate concentrations. Percentage of blueberry was a marginally significant negative predictor in the watershed and freeform polygon models, and percentage of residential coverage was a positive predictor in the freeform polygon and buffer zone models. Spatial autocorrelation was present in the freeform polygon and buffer zone models even after land use was taken into account. In conclusion, analyses based on watersheds produced the best predictive model with the percentages of land cover of potato, hay, and grain being significantly associated with ground water nitrate concentrations, and the percentages of blueberry, clear-cut woodland, and other agriculture being marginally significant.

Riparian buffer zone management is an area of increasing relevance as human modification of the landscape continues unabated. Land and water resource managers are continually challenged to maintain stream ecosystem integrity and water quality in the context of rapidly changing land use, which often offsets management gains. Approaches are needed not only to map vegetation cover in riparian zones, but also to monitor the changes taking place, target restoration activities, and assess the success of previous management actions. To date, these objectives have been difficult to meet using traditional techniques based on aerial photos and field visits, particularly over large areas. Recent advances in remote sensing have the potential to substantially aid buffer zone management. Very high resolution imagery is now available that allows detailed mapping and monitoring of buffer zone vegetation and provides a basis for consistent assessments using moderately high resolution remote sensing (e.g., Landsat). Laser-based remote sensing is another advance that permits even more detailed information on buffer zone properties, such as refined topographic derivatives and multidimensional vegetation structure. These sources of image data and map information are reviewed in this paper, examples of their application to riparian buffer mapping and stream health assessment are provided, and future prospects for improved buffer monitoring are discussed.

1. The Cerrado, a seasonal savanna vegetation, is one of the largest biomes in the Neotropics. Conversion of Cerrado into agroecosystems has caused severe alterations in the species composition, functioning and habitat structure of streams and rivers. 2. As a case study for the Cerrado, the environmental quality of stream-valley systems was investigated in the catchment of the Tenente Amaral River near the city of Jaciara, Mato Grosso, Brazil. 3. Interpreting a Landsat-7 image of the area, and using a rapid assessment protocol with airborne and field observations, 481 first-order streams were identified in the catchment area (875.36 km2), equivalent to an average of 0.55 springs per square kilometre. The total stream density was 0.83 km km−2. 4. Only the uppermost headwater zones of the streams were unimpaired (8.5% of the stream channels). The largest part of the studied stream sectors were moderately (59.3%) or strongly (32.2%) impaired. 5. The greatest impact was caused by erosion. Sediments released by gully erosion alone were calculated as 2.6 × 106 m3 of sediments in the upper zone of one tributary of the Tenente Amaral River. The sediments had deleterious effects on fauna and flora. 6. The highly erosion-prone stream valleys in the Cerrado require full protection. In the transition area between agroecosystems and hillslopes, buffer zones consisting of a replanted interfluvial Cerrado tree vegetation and a vegetated buffer strip should be planted. Apart from erosion protection, these strips can provide valuable income for the farmers through selling non-wood products. 7. The legal situation providing the baseline for the protection of the Cerrado streams is reviewed, including the efforts of the Brazilian states and collaboration of UNESCO. 8. We suggest that it is possible to transfer this management strategy to similar biomes in the seasonal tropics provided that the tree species lists are carefully adapted to the regional flora. Copyright © 2006 John Wiley & Sons, Ltd.

Land cover and land use change have long been known to influence the chemical, physical, and biological character- istics of streams. This study makes use of land cover maps derived from fine resolution satellite imagery and an extensive stream quality dataset to determine the relationship between small water- shed health rankings and land cover composition and configura- tion. Landscape metrics were derived from digital impervious surface area (ISA), tree cover (percent), and agricultural crop maps within Montgomery County, Maryland. Watershed rankings were developed by state and county collaborators (MD-DNR and MCDEP) using extensive biological and chemical measurements. In stepwise logistic regression models the factors accounting for the most variation in stream health ranking were the percent ISA, fol- lowed by the percent of tree cover. Riparian buffer zone tree cover was also a significant predictor. Of the metrics that considered the spatial configuration of the landscape, a contagion index and the percent of ISA in the flow path from the ISA to the stream were also found to be significant predictors of stream health. Despite limited ability to characterize landscape configuration or narrow riparian buffer zone vegetation with coarser resolution imagery (from Landsat), model results were not significantly different from those based on the use of fine-resolution ISA information, suggest- ing that broader area applications of the approach are possible. The results indicate that management practices designed to improve stream water quality should focus on the amount of ISA and tree cover in both the watershed and within the buffer zone. (KEY TERMS: land use planning; remote sensing; restoration; riparian buffers; stream health; urbanization; water quality; water- shed management.)

Human-induced ecological degradation in protected areas is of great concern in landscape ecological studies. Using Landsat TM data and GIS-based spatial analysis, we assessed the impacts of human disturbances on landscape structure in the Wolong Nature Reserve in southwestern China. Buffer zone and landscape dissimilarity analysis were used to examine the scope of three types of human-induced disturbances—construction of hydropower stations, human activities around settlement, and human activities along roads. We found that the impacts of these human disturbances extend to a threshold distance of about 1,000 m from the sources of disturbance. The intensity of the impact of human disturbances on landscape structure exhibited clear distance–decay effects. The first 200 m buffer zone is the area where human activities have inflicted the most visible changes, with a decrease of forest cover by 15–40% and an increase of shrub and barren land area by 15–50%. The relative intensity of the overall impact on landscape structure was highest around hydropower stations, second around human settlements, and lowest along roads. Overtime, however, the relative level of impact associated with construction of hydropower stations will likely decrease and that associated with human activities around settlements likely increase. Our case study of Wolong exposes hurdles that habitat preservation must cross in protected areas. Future management of Wolong Nature Reserve should focus on adoption of effective policies to further constrain human activities in the reserve.

1. The marbled newt, Triturus marmoratus, is a vulnerable urodele species (listed on Annex IV of the European Habitats Directive). However, biological information about their migration and the terrestrial habitats they use is relatively scarce. In order to investigate the influence of the surrounding habitats of a local pond on the directions of pre- and post-breeding migrations, adult newts were monitored over two successive years (from February 2000 to June 2001) at a permanent pond in south-western France using a drift fence and pitfall traps. 2. In both sexes the entry and exit directions were non-randomly distributed. Furthermore, males and females generally followed similar directions facing an oak forest and avoiding barren areas. However, the directions followed by postbreeding migrants leaving the pond differed from those they followed when coming to the pond. 3. The distribution of captures around the pond was related to environmental factors, and more precisely to vegetation within the immediate surroundings of the pond. 4. The environmental conditions occurring at the end of the spring postbreeding migration differed greatly from those occurring during the winter prebreeding migration. Thus, vegetation does not exert similar attraction during the two migration periods. 5. This raises the importance of microhabitat diversity in the vicinity of the breeding pond, which provides a wide range of suitable shelters in different migration periods. Conservation planning must take into account the ecological requirements of this endangered species in managing buffer zones around the breeding sites. Copyright © 2005 John Wiley & Sons, Ltd.

We evaluated the effects of temporary, prominently displayed signs in reducing deer-vehicle collisions (DVCs) during mule deer (Odocoileus hemionus) migrations. To conduct the study we selected segments of 5 highways in 3 western states that were crossed by mule deer during seasonal migrations. Using local input and historical DVC data, we identified migration corridors used by deer. We separated these migration corridors into sections of equal length. Each section was separated by a buffer zone. We randomly assigned each section into treatment or control areas. In treatment areas we erected temporary warning signs equipped with reflective flags and solar-powered flashing amber lights. To evaluate the effectiveness of signs in reducing DVCs, we monitored deer mortalities during migration periods before and after signs were placed. We also monitored vehicle speeds to determine whether the signs affected motorist behavior. DVCs in the treatment areas were reduced by 50%. Vehicle speeds also were reduced, but evidence suggested that the effect eroded during the second year of the study. Study results indicated that temporary signing can be a cost-effective technique when used on roads where DVC peaks occur in conjunction with seasonal migration periods and are isolated to narrow corridors.