Article

Quantitatively Evaluating Restoration Experiments: Research Design, Statistical Analysis, and Data Management Considerations

June 2008
Restoration Ecology 5(4):324 - 337

DOI:10.1046/j.1526-100X.1997.00546.x

Authors:

University of New Mexico

Conceptual and logistical challenges associated with the design and analysis of ecological restoration experiments are often viewed as being insurmountable, thereby limiting the potential value of restoration experiments as tests of ecological theory. Such research constraints are, however, not unique within the environmental sciences. Numerous natural and anthropogenic disturbances represent unplanned, uncontrollable events that cannot be replicated or studied using traditional experimental approaches and statistical analyses. A broad mix of appropriate research approaches (e.g., long-term studies, large-scale comparative studies, space-for-time substitution, modeling, and focused experimentation) and analytical tools (e.g., observational, spatial, and temporal statistics) are available and required to advance restoration ecology as a scientific discipline. In this article, research design and analytical options are described and assessed in relation to their applicability to restoration ecology. Significant research benefits may be derived from explicitly defining conceptual models and presuppositions, developing multiple working hypotheses, and developing and archiving high-quality data and metadata. Flexibility in research approaches and statistical analyses, high-quality databases, and new sampling approaches that support research at broader spatial and temporal scales are critical for enhancing ecological understanding and supporting further development of restoration ecology as a scientific discipline.

A systematic review of the use of statistics in studies of restoration ecology of arid areas

Preprint

Full-text available

Oct 2014

Taylor Noble

Restoration ecology is the study of restoration or restoration practices in degraded areas. It is of particular importance in arid environments due to the heavy impact humans have had in these areas. Some studies of restoration may require different statistics due to the unique challenges faced when examining degraded areas. A systematic review was conducted to assess the use of statistics in the field. It was determined that the field and influence of restoration ecology had increased dramatically since its development. Statistics are widely used in the study of restoration of arid areas. Major tests are similar to those found in other ecological studies such as ANOVAs and linear regressions. There were a few less common tests used in some of the studies. These include tests such as the Mantel test which may be useful to restoration ecology and should be explored further. Finally it was determined that the description of how statistics were used in the study was particularly important. The description should be detailed to help other researchers understand the findings of the paper. This will help to advance the field and the restoration of arid environments.

A systematic review of the statistical scope of restoration ecology of invaded grassland ecosystems

Preprint

Full-text available

Oct 2014

Amanda Rae Liczner

Restoration ecology is a rapidly growing field of research. The statistical analyses and experimental designs used in this field have likely also expanded. In this review, the statistical scope of the restoration ecology of invaded grasslands will be investigated. A systematic review was conducted on 103 articles to examine the types of statistical tests used and how they changed over time, if assumptions are tested, and how the number of statistical tests and the experimental design influence both the citation rate of articles and the impact factor of journals where these articles are published. ANOVAs have consistently been the dominant test. Statistical test diversity has increased since the year 2000. Most articles did test the assumptions of statistical analyses. The number of tests, and sample size of experiments are both positively correlated with the average citation rate of articles and the impact factor of the journal while the number of factors was negatively correlated. GLMs are recommended as a statistical test to be used more frequently in the future over ANOVAs. There is room for improvement in terms of reporting statistics accurately, including testing assumptions. When possible, sample sizes should be increased to both increase the quality of data, and the citation rate and the journal impact where articles are published. When possible and appropriate, sample sizes and the number of statistical tests should be increased. Adding factors in experimental designs should only be done so without compromising sample size as it has been shown to hinder the citation rate and journal impact.

Impacts of Riparian Restoration on Vegetation and Avifauna on Private and Communal Lands in Northwest Mexico and Implications for Future Efforts

Article

Full-text available

Jul 2020

Restoring and enhancing riparian vegetation on private and communal lands in Mexico is important for biodiversity conservation given the ecological significance of these areas and the scarcity of public protected areas. To enhance riparian vegetation and wildlife habitats and train local people in restoration techniques, we implemented restoration and outreach efforts on private and communal lands in the Sky Islands region of northwest Mexico. We fenced 475 ha of riparian zones from livestock, erected erosion-control structures, planted trees, and developed management agreements for cool-season grazing with landowners on 10 ranches across 3 sites in 2012-2013, then repaired fences and renegotiated agreements in 2017-2019. To foster evaluation, we used a before-after/control-impact design to measure attributes of vegetation structure and bird communities and compared baselines from 2012 with post-treatment estimates from 2019. As predicted, understory vegetation volume generally increased in treatments relative to controls (P = .09), especially when one treatment area with the lowest pre-treatment grazing impacts was censored (P = .01). Although canopy cover also increased, there was little differential change in treatments relative to con-trols (P ⩾ .23) due likely to longer time periods needed to realize responses. Densities of most focal bird populations varied across time periods in directions that typically matched observed changes in vegetation structure, but fewer species showed signs of differential positive change linked to treatments relative to controls. Densities of Yellow-breasted Chat, a key understory obligate and important focal species, increased in treatments relative to controls across sites, as did densities of Sinaloa Wren, which also use dense underbrush (P⩽ .05). Positive changes by other understory obligates (eg, Common Yellowthroat, Song Sparrow) were more local but sometimes of high magnitude (>8-fold) also suggesting positive impacts of treatments. Despite mixed results over a limited time period, these patterns suggest restoration efforts drove localized recovery of understory vegetation and associated bird populations, but benefits varied widely with environmental and social factors linked to management. Greater ecological benefits to riparian areas on private and communal lands in this region can be fostered by further incentivizing construction, maintenance, and proper use of restoration infrastructure, through education, and by building relationships based on trust and credibility with landowners

Restore it, and they will come: trap-nesting bee and wasp communities (Hymenoptera: Aculeata) are recovered by restoration of riparian forests

Article

Full-text available

Apr 2018
J INSECT CONSERV

Riparian forests have been greatly affected by anthropogenic actions with formerly continuous riparian forests being slowly converted into small and isolated patches. Riparian forests are extremely important habitats for many groups of insects, including bees and wasps, because they are sources of shelter and food for them and their offspring. There is a growing body of evidence of success in the restoration of riparian forest plant communities; however, little research has been done on the associated invertebrate communities. We test whether restoring plant communities is sufficient for restoring the taxonomic composition of trap-nesting bees and wasps and which functional traits are favored in different sites. We predict that species richness, abundance, and community composition of trap-nesting bees and wasps of riparian sites undergoing restoration will converge on the “target” of a reference site with increasing time, since restoration increases habitat complexity. We also predict that the width of restored patches will also influence the species richness, abundance and community composition of trap-nesting bees and wasps. Bee richness and abundance, and wasp richness, were strongly related to fragment width, but not to age since restoration. Our results indicate that although restored sites are relatively small and scattered in a fragmented landscape, they provide suitable habitat for re-colonization by community assemblages of trap-nesting bees and wasps and the traits selected captured the responses to the habitat restoration. Hence, restored riparian areas can be considered important habitats for invertebrates, thus contributing to an increase in local biodiversity and, possibly, the restoration of some of the ecosystem services they originally provided.

Evaluating the success of wildlife crossing structures using genetic approaches and an experimental design: Lessons from a gliding mammal

Article

Jul 2017
J APPL ECOL

Millions of dollars are spent on wildlife crossing structures intended to reduce the barrier effects of roads on wildlife. However, we know little about the degree to which these structures facilitate dispersal and gene flow. Our study incorporates two elements that are rarely used in the evaluation of wildlife crossing structures: an experimental design including a before and after comparison, and the use of genetic techniques to demonstrate effects on gene flow at both population and individual levels. We evaluated the effect of wildlife crossing structures (canopy bridges and glider poles) on a gliding mammal, the squirrel glider (Petaurus norfolcensis). We genotyped 399 individuals at eight microsatellite markers to analyse population structure, first-generation migrants and parentage relationships. We found that the freeway was not a complete genetic barrier, with a strong effect evident at only one site. We hypothesise that the presence of corridors alongside the freeway and throughout the surrounding landscape facilitated circuitous detours for squirrel gliders. Installing a crossing structure at the location with a strong barrier effect restored gene flow within just five years of mitigation. Synthesis and applications. Our study highlights the importance of using genetic techniques not just to evaluate the success of road crossing structures for wildlife, but also to guide their placement within the landscape. Managers wishing to reduce the effects of linear infrastructure on squirrel gliders and other arboreal mammals should aim to preserve and enhance vegetation along roadsides and within centre medians, as well as mitigate large gaps by implementing wildlife crossing structures.

Long-term impacts of urban floodplain management and habitat restoration on lizard communities in a Sonoran Desert City

Article

Full-text available

Nov 2023
ECOL ENG

Riparian zones are critical for biodiversity but have suffered widespread degradation and therefore are key targets for ecological restoration. In urban contexts, restoring riparian ecosystems can have widespread benefits but these efforts are often limited by needs to mitigate flood risks and by a lack of long-term monitoring to evaluate efficacy, presenting important challenges for managers. To evaluate restoration potential in urban riparian systems, we studied responses of a diverse Sonoran Desert lizard community to combined flood control and habitat restoration efforts along a major river course and tributary drainage over 15 years in urban Tucson, Arizona. We used a before/after-control/impact design and linear mixed-effect models to estimate species responses to treatments that included bank stabilization and detention basin construction for flood and erosion control combined with passive water harvesting, native vegetation planting and seeding, and targeted creation of microhabitats. Despite marked declines of relative abundances and richness at treated sites immediately following construction, overall impacts were mostly positive or neutral, and negative for just one of six focal species. Most species recovered to pre-treatment levels of abundance within 2-3 years, but recovery dynamics varied with differences in life history traits and habitat use among species. In general, widely-moving, faster-maturing terrestrial species recovered more quickly and responded most positively to restoration, whereas more arboreal species with longer generation times and smaller home ranges took longer to benefit from restoration treatments. Few studies assess impacts of paired urban flood control and habitat restoration on wildlife, and our findings suggest management of urban riparian systems can provide simultaneous benefits to humans and wildlife. Future efforts may be improved by preserving and fostering more heterogeneous cover including key resources such as mature trees, as well as potentially translocating animals into restored but disconnected patches of habitat in urbanized landscapes.

Enhancing the Long-Term Ecological Management and Monitoring of Landscapes: The L-TEAM Framework

Article

Full-text available

Oct 2023

Long-term monitoring and adaptive ecological management are essential to the conservation of biodiversity. Yet, achieving successful long-term ecological monitoring and management, especially at the landscape level, has proven challenging. In this paper, we address the hurdles faced in sustaining long-term monitoring and management for landscape-scale efforts by offering three promising conceptual and methodological developments that support such initiatives. Then, we introduce L-TEAM, a long-term ecological adaptive monitoring and management framework that integrates those three components using four tools: a conceptual model, clearly defined and measurable objectives, scientifically robust experimentation, and decision support tools. Finally, using a case study, we demonstrate L-TEAM’s effectiveness in supporting the long-term monitoring and management of a landscape conservation project with diverse habitat types and multiple management objectives. This structured decision framework not only facilitates informed decision making in management practices, but also ensures the implementation of scientifically grounded long-term monitoring. Additionally, L-TEAM holds the potential to enhance our understanding of ecosystem functioning and biodiversity responses to disturbances and management actions.

Not all seed transfer zones are created equal: using fire history to identify seed needs in the Cold Deserts of the western United States

Article

Full-text available

Sep 2023

Restoration planning requires a reliable seed supply, yet many projects occur in response to unplanned events. Identifying regions of greater disturbance risk could efficiently guide seed procurement. Using fire in U.S. Cold Deserts as an example, we demonstrate how historic disturbance can inform seed production choices. We compared differences in fire frequency, area burned, and percent of area burned among different management areas, identifying regions of particular need. We also present a case study focused on fire occurrence within important wildlife habitat, specifically looking at the greater sage‐grouse priority areas for conservation (PACs) within the Northern Basin and Range ecoregion. We used geospatial seed transfer zones as our focal management areas. We broadly considered generalized provisional seed transfer zones, created using climate and stratified by ecoregion, but also present results for empirical seed transfer zones, based on species‐specific research, as part of our case study. Historic fire occurrence was effective for prioritizing seed transfer zones: 23 of 132 provisional seed transfer zones burned every year, and, within each ecoregion, two provisional seed transfer zones comprised ≧50% of the total area burned across all years. Fire occurrence within PACs largely reflected the seed transfer zone priorities found for the ecoregion as a whole. Our results demonstrate that historic disturbance can be used to identify regions that encounter regular or large disturbance. This information can then be used to guide seed production, purchase, and storage, create more certainty for growers and managers, and ultimately increase restoration success.

Long-term, large-scale experiment reveals the effects of seed limitation, climate, and anthropogenic disturbance on restoration of plant communities in a biodiversity hotspot

Article

Feb 2023
P NATL ACAD SCI USA

Ecological restoration is essential for maintaining biodiversity in the face of dynamic, global changes in climate, human land use, and disturbance regimes. Effective restoration requires understanding bottlenecks in plant community recovery that exist today, while recognizing that these bottlenecks may relate to complex histories of environmental change. Such understanding has been a challenge because few long-term, well-replicated experiments exist to decipher the demographic processes influencing recovery for numerous species against the backdrop of multiyear variation in climate and management. We address this challenge through a long-term and geographically expansive experiment in longleaf pine savannas, an imperiled ecosystem and biodiversity hotspot in the southeastern United States. Using 48 sites at three locations spanning 480 km, the 8-y experiment manipulated initial seed arrival for 24 herbaceous plant species and presence of competitors to evaluate the impacts of climate variability and management actions (e.g., prescribed burning) on plant establishment and persistence. Adding seeds increased plant establishment of many species. Cool and wet climatic conditions, low tree density, and reduced litter depth also promoted establishment. Once established, most species persisted for the duration of the 8-y experiment. Plant traits were most predictive when tightly coupled to the process of establishment. Our results illustrate how seed additions can restore plant diversity and how interannual climatic variation affects the dynamics of plant communities across a large region. The significant effects of temperature and precipitation inform how future climate may affect restoration and conservation via large-scale changes in the fundamental processes of establishment and persistence.

Grazing capacity change on a small Mediterranean-type South African offshore island following the control of invasive alien European rabbits (Oryctolagus cuniculus)

Article

Dec 2022

Invasive alien species (IAS) are one of the most important factors driving extinction rates worldwide. Among the IAS, the impacts of introduced mammals on native biodiversity are most severe, with the European rabbit (Oryctolagus cuniculus) being the most problematic. Globally, European rabbits have been introduced to five continents and more than 800 islands or island groups where they are a threat to biodiversity and human livelihoods. The impacts of European rabbits on biodiversity and human livelihoods have been extensively studied across the globe. However, some regions of the world, such as the offshore islands along Africa’s southern coast, have been sparsely studied. In this study, we monitored change in grazing capacity on a South African offshore island, Robben Island, following an attempt to eradicate European rabbits between 2008 and 2009. Grazing capacity on the island increased following rabbit control, driven by the recovery of palatable plant species in response to release from herbivory. There was no change in grazing capacity at sites under Eucalyptus plantations because of the inhibitory effects of the alien trees on understory vegetation dynamics. We believe that grazing capacity changes on Robben Island are indicative of potential vegetation changes on other southern African offshore islands.

Quels objectifs de restauration pour un ancien polder de la basse vallée du Vistre ?

Article

Jan 2002

In areas deeply modified by human activities, the target ecosystems for restoration and / or rehabilitation projects can seldom be related to known reference systems accepted by all parties. Such projects are hence constructed around objectives defined with the owner according to a combination of biological, hydrological, social and political criteria. The rehabilitation on the Vistre marshes (Gard, France) was in such a way orientated by multiple objectives. The change of the fallow land towards a wetland with floodplain functions, a regional patrimonial value, can be considered a success. The area is dry by the end of summer and is filled annually by autumn floods. It supports fish communities that attract fish eating birds. The colony of tree nesting herons is one of the most important of the region, and hosts a significant proportion of the French population of Squacco Heron (Ardeola ralloides). Moreover, it was turned into a Nature Reserve before the end of the project. However, a detailed analysis leads to a more critical evaluation of the multi-objective choice done initially. It led to abundant and costly monitoring studies that did not necessarily provide useful answers. It was for example not possible to conclude to what extent the area was a sink for nutrients. The need for social and economic studies was under-evaluated despite objectives of human use (hunting, grazing and reed harvesting). It was concluded that such a project should be more strictly aimed to few targets, monitored and evaluated rigorously. Additional biological, hydrological, economical or social issues, in that case would be taken into account only when compatible with the priority objectives set. The initial choices have to be defined carefully and agreed upon by all stakeholders.

Diversity of herpetofauna at restored cranberry bogs: A comparative survey of herpetofaunal diversity at a restored wetland in comparison to a retired cranberry bog to assess the restoration success

Article

Full-text available

Jan 2022
HERPETOL J

Wetlands perform critical ecological functions and provide wildlife habitats. Yet, wetland degradation continues at a global scale. In Massachusetts, USA, wetland restoration has reached remarkable heights, partly promoted by the retirement of cranberry bogs. In this study, to assess the effectiveness of cranberry-farm restoration for conservation of native herpetofauna, we surveyed both retired and restored cranberry bogs in southeastern Massachusetts. Using both visual encounter surveys and baited aquatic traps, we documented herpetofaunal species and their relative abundance. Both survey methods combined, the cumulative herpetofaunal species richness at the restored bogs (16) exceeded that of the retired bogs (11). Our trap surveys indicated that the amphibian species richness at the retired bog was significantly greater than that of the restored bog. In contrast, reptilian species richness as well as the relative abundance of both amphibians and reptiles were significantly greater at the restored bog compared to the retired bog. Subsequent analyses we performed identified that greater habitat heterogeneity emerging from active restoration intervention was the underlying driver of elevated richness and abundance. Most frequently encountered herpetofauna at the restored versus retired bogs were habitat generalists with broader geographic ranges and are not of conservation concern. Our findings suggest that the restored bog we monitored is still in the early-recovery phase after active intervention. We urge the need for long-term herpetofaunal inventories via systematic, standard surveys to assess restoration success.

Bayesian modeling can facilitate adaptive management in restoration

Article

Full-text available

Oct 2021

There is an urgent need for near-term predictions of ecological restoration outcomes despite imperfect knowledge of ecosystems. Restoration outcomes are always uncertain but integrating Bayesian modeling into the process of adaptive management allows researchers and practitioners to explicitly incorporate prior knowledge of ecosystems into future predictions. While barriers exist, employing qualitative expert knowledge and previous case studies can help narrow the range of uncertainty in forecasts. Software and processes that allow for repeatable methodologies can help bridge the existing gap between theory and application of Bayesian methods in adaptive management. This article is protected by copyright. All rights reserved.

Response of eelgrass (Zostera marina) to an adjacent Olympia oyster restoration project

Article

Full-text available

Oct 2021
PLOS ONE

Recent restoration efforts for the native Olympia oyster, Ostrea lurida, are commonly motivated by potential return of oyster-associated ecosystem services, including increased water filtration. The potential impact of such restoration on another species of ecological concern, eelgrass, Zostera marina, is unclear, but has been hypothesized to be positive if oyster filter feeding increases light penetration to eelgrass. For two years after construction of an oyster restoration project, we assessed the response of adjacent eelgrass (impact) compared to control and reference eelgrass beds by monitoring changes in light intensity, eelgrass shoot density, biomass, leaf morphometrics, and epiphyte load. We observed lower light intensity consistently over time, including prior to restoration, near the constructed oyster bed relative to the control and one of the reference locations. We also observed minor variations between control and impact eelgrass morphology and density. However, the changes observed were not outside the range of natural variation expected in this system, based upon comparisons to reference eelgrass beds, nor were they detrimental. This limited impact to eelgrass may be due in part to the incorporation of a buffer distance between the restored oyster bed and the existing eelgrass bed, which may have dampened both positive and negative impacts. These findings provide evidence that Olympia oyster restoration and eelgrass conservation goals can be compatible and occur simultaneously.

Reversing tree expansion in sagebrush steppe yields population‐level benefit for imperiled grouse

Article

Full-text available

Jun 2021

Woody plant expansion into shrub and grasslands is a global and vexing ecological problem. In the Great Basin of North America, the expansion of pinyon–juniper (Pinus spp.–Juniperus spp.) woodlands is threatening the sagebrush (Artemisia spp.) biome. The Greater Sage‐grouse (Centrocercus urophasianus; sage‐grouse), a sagebrush obligate species, is widespread in the Great Basin and considered an indicator for the condition of sagebrush ecosystems. To assess the population response of sage‐grouse to landscape‐scale juniper removal, we analyzed a long‐term telemetry data set and lek counts with a Bayesian integrated population model in a before‐after‐control‐impact design. Population growth rates (λ) in a treatment area (Treatment) with juniper removal and a control area (Control) without juniper removal indicated the two areas generally experienced population increase, decrease, and stability in the same years. However, the difference in λ between study areas indicated a steady increase in the Treatment relative to the Control starting in 2013 (removals initiated in 2012), with differences of 0.13 and 0.11 in 2016 and 2017, respectively. Retrospective sensitivity analysis suggested the dynamics in λ were driven by increases in juvenile, adult, first nest, and yearling survival in the Treatment relative to the Control. These findings demonstrate the effectiveness of targeted conifer removal as a management strategy for conserving sage‐grouse populations in sagebrush steppe affected by conifer expansion. Examples of positive, population‐level responses to habitat management are exceptionally rare for terrestrial vertebrates, and this study provides promising evidence of active management that can be implemented to aid recovery of an imperiled species and biome.

New Needed Quality Management Skills for Quality Managers 4.0

Article

Full-text available

May 2021

These transformations will change the industrial landscape, toward Quality 4.0 and therefore, our lives. The presented research was conducted on quality management employees in Portugal and it aims to analyze if such employees have the perception of the impact of Industry 4.0 in the quality management profession and the required and needed skills. After analyzing the answered questionnaires, 90 results were considered valid. This is the sample of our study. Simultaneously, the goal of this research is also to review and analyze the main topics in progress related to quality management for the fourth industrial revolution and how quality emerges of this change. The professionals that work on quality management must have creative thinking, be leaders, know how to communicate and work as a team, as well as, to have knowledge and understanding of ICT (Information and Communications Technology), and main pillars of Industry 4.0. These are the main findings. Besides that, they must know how to motivate their work teams, be open to change, know how to use Big Data to make decisions and above all, they must know how to manage conflicts. In addition, quality professionals must promote the design and production of first class products, be the defenders of their customers within the organization , and finally, they must create value for the stakeholders.

Advancing ecological restoration through experimental design on spatial and temporal scales relevant to wildlife

Preprint

Full-text available

Nov 2017

Experimenting with new and unconventional restoration methods and designs is critical to advancing the field of ecological restoration. Conventional methods cannot be considered reliable in a future with climate change-induced shifts in weather conditions, species distributions, and ecosystem processes. It is crucial that researchers and practitioners collaborate to identify the most effective restoration methods, yet there remains a disturbing lack of restoration experiments at the spatial or temporal scales relevant for evaluating wildlife responses. We suspect that willingness to attempt such experiments is hampered by the perceived difficulty of conducting these experiments combined with a fear of failure. However, we argue that failure to experiment with new methods guarantees learning nothing new. Here, we address many of the major challenges of designing an experiment to evaluate wildlife responses to restoration, including (1) distinguishing between the goals and objectives of the restoration project and the key uncertainties the experiment will address, (2) designing the experiment itself, including optimizing plot size and replication, and (3) determining how and when the results will be evaluated. We then illustrate how we designed an experiment to evaluate riparian bird responses to restoration along the lower Cosumnes River in the Central Valley of California, USA. Researchers and practitioners working together from the start of the objectives-setting process, through experimental design, implementation, and evaluation can proactively address the challenges of conducting a restoration experiment and maximize the chances of successfully identifying effective restoration methods, adding to the practitioners’ toolbox, and accelerating the rate of successful habitat restoration.

Can Vegetation Removal Successfully Restore Coastal Dune Biodiversity?

Article

Full-text available

Mar 2020

Coastal dune habitats have been declining globally over the last several decades due to rapid urbanization. Within remaining dune systems, dune fixation has resulted in further losses of mobile dunes with negative impacts on their associated species. Some studies suggest vegetation removal can initially promote habitat heterogeneity, and increase availability of suitable habitats for psammophile, xeric and endemic mobile dune species, but longer-term responses are generally unknown. We investigated the temporal trends of four taxonomic groups to determine the effect of vegetation removal on dune assemblages over a 12-year period at an LTER site. Three different forms of removal are investigated here—removal in a grid form on fixed dunes, removal of the wind-facing slope vegetation on semi-fixed dunes and opportunistic off-road driving on disturbed dunes. Results were varied across taxa, highlighting the need for multi-taxa monitoring in conservation and restoration management. Overall, fixed dune treatment had very little effect, while a stronger response was found in semi-fixed treatments in particular for mobile dune indicator species, which showed evidence of recolonization within a few years following treatment. Disturbed dunes were most similar to mobile dunes for animal taxa indicating that pulse removal may not be as effective as continuous press disturbance. Nevertheless, a less destructive form of disturbance such as re-introduction of grazing might be preferable and requires further investigation.

PERCEPTION OF THE IMPORTANCE TO IMPLEMENT ISO 9001 IN ORGANIZATIONS RELATED TO PEOPLE LINKED TO QUALITY – AN EMPIRICAL STUDY

Article

Full-text available

Nov 2019

Quality Management has been one of the most dominating and pervasive managerial approaches all over the world during the last three decades. The questionnaire of this study included different information, of where we can highlight: the perception of the importance having implemented the ISO 9001 standard; the most used quality tools/techniques in the professional activities. As main conclusions we can highlight: women attach great importance to the implementation of the ISO 9001 standard, namely as regards on customer satisfaction, in the competitiveness of the Organization and in the relationship with customers and give less importance in individual performance, in motivation of professionals and in the evolution of sales. Men value the implementation of the ISO 9001 more, namely regarding to the relationship with customers, in the management mode and they give less importance to the evolution of sales and to the motivation of professionals.

Effects of a retaining wall and an artificial embankment on nearshore littoral habitats and biota in a large Alpine lake

Article

Full-text available

Jan 2020
HYDROBIOLOGIA

The littoral zones of many Central European lakes are severely altered by lake-side retaining walls. These are suspected to impair littoral biota due to the reflection of incoming wave energy. We conducted a comparative study (armoured shore with a retaining wall and a restored shore with a wedge-shaped cobble embankment vs. a pristine shore) at a wind-exposed shore section of Lake Constance. The retaining wall had a number of significant remote effects on the littoral zone, i.e. increased near-bottom current velocities, higher bed-load transport rates, coarsening of surface sediments, reduction in phytomass density, reduction in total densities and number of taxa of macroinvertebrates as well as a significant decline in the percentages of Limnomysis benedeni Czerniavsky, 1882, Ostracoda, Corbicula fluminea O.F. Müller, 1774, Dreissenapolymorpha (Pallas, 1771) and other Bivalvia. However, the significantly affected zone had a rather narrow width of ~ 3 m. Shore restoration measures are needed to remediate negative effects of retaining walls and re-establish ecological conditions that are comparable to those of pristine shores. We recommend a more site sensitive sampling strategy, e.g. for macroinvertebrates in context with the ecological quality assessment under the European Water Framework Directive.

DESIGN OPTIONS, IMPLEMENTATION ISSUES and EVALUATING SUCCESS OF ECOLOGICALLY-ENGINEERED SHORELINES

Article

Full-text available

Aug 2019

Human population growth and accelerating coastal development have been the drivers for unprecedented construction of artificial structures along shorelines globally. Construction has been recently amplified by societal responses to reduce flood and erosion risks from rising sea levels and more extreme storms resulting from climate change. Such structures, leading to highly modified shorelines, deliver societal benefits, but they also create significant socioeconomic and environmental challenges. The planning, design and deployment of these coastal structures should aim to provide multiple goals through the application of ecoengineering to shoreline development. Such developments should be designed and built with the overarching objective of reducing negative impacts on nature, using hard, soft and hybrid ecological engineering approaches. The design of ecologically sensitive shorelines should be context-dependent and combine engineering, environmental and socioeconomic considerations. The costs and benefits of ecoengineered shoreline design options should be considered across all three of these disciplinary domains when setting objectives, informing plans for their subsequent maintenance and management and ultimately monitoring and evaluating their success. To date, successful ecoengineered shoreline projects have engaged with multiple stakeholders (e.g. architects, engineers, ecologists, coastal/port managers and the general public) during their conception and construction, but few have evaluated engineering, ecological and socioeconomic outcomes in a comprehensive manner. Increasing global awareness of climate change impacts (increased frequency or magnitude of extreme weather events and sea level rise), coupled with future predictions for coastal development (due to population growth leading to urban development and renewal, land reclamation and establishment of renewable energy infrastructure in the sea) will increase the demand for adaptive techniques to protect coastlines. In this review, we present an overview of current ecoengineered shoreline design options, the drivers and constraints that influence implementation and factors to consider when evaluating the success of such ecologically engineered shorelines

Design Options, Implementation Issues and Evaluating Success of Ecologically Engineered Shorelines

Chapter

Full-text available

Aug 2019

Linking fish trait responses to in‐stream habitat in reconstructed valley‐plugged stream reaches of the Coastal Plain, U.S.A.

Article

Full-text available

Aug 2019

Valley plug formation is a challenging consequence of stream channelization especially in physiographic regions with highly erodible soils. Upstream channel degradation and incision results in accelerated sediment delivery processes wherein downstream aggradation decreases stream power and creates sand‐clogged channels. Channel reconstruction is now meeting hydrogeomorphic goals related to valley plug remediation yet there exists a need to understand how this practice also facilitates ecological restoration. We evaluated fish trait response to in‐stream habitat conditions in channelized, recently restored, and ‘least‐disturbed’ reference reaches of Coastal Plains streams in West Tennessee. Restored reaches were ecologically similar to channelized reaches, having higher proportions of nest‐guarding omnivores that were correlated with higher percentages of pool habitats and lower wetted width:depth ratios compared to reference reaches. Reference reaches had higher proportions of fast‐water dwelling and specialized insectivores that were correlated with high abundance of large woody debris, high wetted width:depth ratios, and low percentages of pool habitats. We conclude that in‐stream habitats in reconstructed channels have yet to promote reach‐scale ecological restoration relative to fish assemblage organization because trait‐habitat associations were not similar to reference conditions. However, our results lend to the development of ecological restoration targets that can be incorporated in future channel reconstruction projects in valley‐plugged, channelized streams of the Coastal Plains. This article is protected by copyright. All rights reserved.

Are We Getting Better in Using Nitrogen?: Variations in Nitrogen Use Efficiency of Two Cereal Crops Across the United States

Article

Full-text available

Aug 2019

Abstract Spatial variation and temporal trajectory of crop nitrogen use efficiency (NUE) have important implications for nitrogen management and environmental conservation. Previous studies have examined cross‐nation divergences in crop NUE but often overlooked its spatial heterogeneity and cross‐crop differences at subnational scales. We examined the relationship between state‐level NUE and nitrogen fertilizer use for two major fertilizer‐consuming crops, corn and winter wheat, which account for over half of national N fertilizer use in the United States. Since 1970, as N fertilizer use rates have changed, the responses of crop yield and NUE have exhibited large temporal and spatial variations. It is evident that NUE of corn begins to decline when N fertilizer application rate exceeds ~150 kg N ha−1 yr−1, and that yield response of winter wheat slows down with annual N fertilizer input above ~50 kg N ha−1 yr−1. State‐level NUE in both crops has risen in recent decades, which could potentially reduce N loss from agricultural production. Across the United States, some major corn‐producing states demonstrate a shift from an increasing trend of NUE during the period 1970 to 1999 to a decreasing trend after 2000, whereas winter wheat‐producing states present an opposite pattern. Furthermore, this study indicates that annual dynamics of N surplus in corn is closely tied with grain yields, while that in winter wheat significantly correlates with N fertilizer input. A larger proportion of N loss would be anticipated if no further increase in corn yield was obtained or fertilizer use kept rising in winter wheat.

Diagnóstico ecológico, formulación e implementación de estrategias para la restauración de un bosque seco tropical interandino (Huila, Colombia)

Article

Full-text available

Apr 2019

El diagnóstico ecológico regional es fundamental para planificar procesos de restauración ecológica (RE), especialmente en ecosistemas poco conocidos y amenazados como el Bosque Seco Tropical (bs-T). A partir del diagnóstico ecológico de un bs-T en el departamento del Huila, Colombia, se formuló, implementó e inició el monitoreo de seis estrategias para su restauración. Para los escenarios de restauración se identificaron las barreras a la regeneración natural y sus facilitadores, los ecosistemas de referencia y las especies clave. Con esta información se formularon seis estrategias de restauración: i) nucleación en pastizales abiertos con núcleos entre 2x2 m y 32x32 m con variación en el número de especies (3–30), número de individuos (9–196), ensambles de especies (1–4) y manejo del suelo, ii) siembra bajo árboles nodriza en pastizales arbolados con 37 individuos de seis especies, iii) siembra bajo agrupaciones de árboles con 57 individuos de once especies, iv) ampliación de borde de bosques y arbustales con fajas de 10x5 m con 17 individuos de cinco especies, v) enriquecimiento en arbustales y bosques en módulos hexagonales monoespecíficos de siete individuos, y vi) restauración espontánea. La siembra total fue de 54 300 individuos con mayor esfuerzo en la nucleación de 32x32 m con 159 réplicas y 21 676 individuos. El monitoreo a largo plazo permitirá evaluar el desarrollo de trayectorias sucesionales acorde con las referencias y determinar el costo efectividad de las estrategias. Este proceso metodológico de diagnóstico ecológico, formulación, implementación y monitoreo de estrategias puede servir como guía importante para la RE del bs-T en otras localidades.

Open-File Report 2013-1133 Prepared for the California Department of Water Resources, Salton Sea Ecosystem Restoration Program Salton Sea Ecosystem Monitoring and Assessment Plan

Technical Report

Full-text available

Jan 2013

The Salton Sea, California’s largest lake, provides essential habitat for several fish and wildlife species and is an important cultural and recreational resource. It has no outlet, and dissolved salts contained in the inflows concentrate in the Salton Sea through evaporation. The salinity of the Salton Sea, which is currently nearly one and a half times the salinity of ocean water, has been increasing as a result of evaporative processes and low freshwater inputs. Further reductions in inflows from water conservation, recycling, and transfers will lower the level of the Salton Sea and accelerate the rate of salinity increases, reduce the suitability of fish and wildlife habitat, and affect air quality by exposing lakebed playa that could generate dust.

THE QUARTERLY REVIEW of Biology GUT MICROBIOTA AND HUMAN HEALTH: INSIGHTS FROM ECOLOGICAL RESTORATION

Preprint

Full-text available

Jun 2018

Dysbiosis of the gut facilitates chronic diseases such as cancer, obesity, and autoimmune disorders. Successful treatment may require restoration of functions performed by symbiotic microbes. The field of ecological restoration has restored species diversity and ecosystem function of natural habitats since the latter part of the 20th century, but its possible applications to medicine are unexplored. Here we show that approaches developed to restore natural ecosystems may aid in the treatment of chronic disease by helping to characterize target conditions for healthy microbe communities, by identifying the importance of donor diversity in fecal microbiota transplants, and by elevating the importance of diet, patient involvement , and personalized medicine in gut health. Dialogue between the fields of restoration ecology and medicine may help to guide future directions in gut research and clinical care.

Gut Microbiota and Human Health: Insights From Ecological Restoration

Article

Full-text available

Jun 2018

Dysbiosis of the gut facilitates chronic diseases such as cancer, obesity, and autoimmune disorders. Successful treatment may require restoration of functions performed by symbiotic microbes. The field of ecological restoration has restored species diversity and ecosystem function of natural habitats since the latter part of the 20th century, but its possible applications to medicine are unexplored. Here we show that approaches developed to restore natural ecosystems may aid in the treatment of chronic disease by helping to characterize target conditions for healthy microbe communities, by identifying the importance of donor diversity in fecal microbiota transplants, and by elevating the importance of diet, patient involvement, and personalized medicine in gut health. Dialogue between the fields of restoration ecology and medicine may help to guide future directions in gut research and clinical care.

Review on vegetation phenology observation and phenological index extraction

Article

Apr 2016

Vegetation phenology directly reflects the response of ecosystem physiological and ecological processes to environmental changes and has received increasing attention in climate change, which leads to the development of various phenology monitoring techniques and methods of extracting the phenological index. Based on relevant literatures, the monitoring techniques of vegetation phenology were reviewed. Second, the methods of extracting phenological index using different techniques were introduced systematically. Thirdly, the differences from multi-source data and from multi-methods were evaluated based on ground phenology record, flux observation and vegetation index. Although various methods have been adopted in current vegetation phenological studies, it should be aware of their appropriately spatiotemporal scales for different methods, and the mutual complementation will help to improve the system for phenology monitoring. Meanwhile, the comparison indicated the obvious differences in derived vegetation phenological index using various observation techniques and extraction methods, especially for the autumn vegetation phenological index. Such results highlight the importance to assess reasonably these differences from multi-source data and from multi-methods, and to establish a rational processing system for the mutual comparison and conversion from different methods.

Advancing ecological restoration through experimental design on spatial and temporal scales relevant to wildlife

Preprint

Full-text available

Mar 2018

Analysing methodological issues in short-term monitoring of rare European beech forests restoration

Article

Mar 2018

Monitoring restoration effectiveness implies that restoration measures should be evaluated using multiscale analysis and modelling approaches. In this way, the scale-dependent nature of ecosystem processes and dynamics can be adequately described. Here, we evaluated how grain size (i.e. the dimension of sampling units) and type of data (abundance vs. presence/absence) impact the analysis of the response to restoration management activities aiming at halting the loss of European beech forests with Abies alba in the central Apennines (Italy). The proposed analysis relies on forests sampled in three Sites of Community Importance (SCIs) located in central Italy. For each treatment (reference, control and impact), randomly located multi-scale plots were selected. Vascular plant occurrences were recorded twice in every plot during summer 2010 or 2011 (before restoration) and in 2013 or 2014 (after restoration). Analysis of species abundances, recorded at the largest grain size available (20 X 20 m plot), showed a significant change in plant species composition in restored sites just after two years from the restoration management. When presence/absence data were used previous results were less visible, for all the examined grains, in two out of the three sites, suggesting a site-dependent response.

An Ecological Framework for Forest and Fire Restoration in the Klamath-Siskiyou Region of Northwest California and Southwest Oregon

Technical Report

Full-text available

Jan 2001

Evan Frost

Restoring Sage-grouse nesting habitat through removal of early successional conifer

Article

Full-text available

Jan 2017

Conifer woodlands have expanded into sagebrush (Artemisia spp.) ecosystems and degrade habitat for sagebrush obligate species such as the Greater Sage-grouse (Centrocercus urophasianus). Conifer management is increasing despite a lack of empirical evidence assessing outcomes to grouse and their habitat. Although assessments of vegetation recovery after conifer removal are common, comparisons of successional trends with habitat guidelines or actual data on habitat used by sage-grouse is lacking. We assessed impacts of conifer encroachment on vegetation characteristics known to be important for sage-grouse nesting. Using a controlled repeated measures design, we then evaluated vegetation changes for 3 years after conifer removal. We compared these results to data from 356 local sage-grouse nests, rangewide nesting habitat estimates, and published habitat guidelines. We measured negative effects of conifer cover on many characteristics important for sage-grouse nesting habitat including percent cover of forbs, grasses, and shrubs, and species richness of forbs and shrubs. In untreated habitat, herbaceous vegetation cover was slightly below the cover at local nest sites, while shrub cover and sagebrush cover were well below cover at the nest sites. Following conifer removal, we measured increases in herbaceous vegetation, primarily grasses, and sagebrush height. Our results indicate that conifer abundance can decrease habitat suitability for nesting sage-grouse. Additionally, conifer removal can improve habitat suitability for nesting sage-grouse within 3 years, and trajectories indicate that the habitat may continue to improve in the near future. Implications for Practice • Increased conifer cover in sagebrush ecosystems reduces shrub understory vegetation characteristics important for sage-grouse nesting, thereby limiting habitat suitability and availability for sage-grouse. • Conifer removal increases herbaceous vegetation in a short time period which increases habitat suitability for sage-grouse nesting habitat. Shrubs may not respond as quickly. • Different conifer removal methods may have differing impacts on understory vegetation. Managers should consider and attempt to limit potential negative affects, such as decreased shrub cover or increased exotic annual grasses, when planning conifer removal projects. • Managers should first focus conifer removal efforts in areas with intact shrub and herbaceous composition to achieve the quickest and most complete habitat recovery.

Mobile and Game Usage, Gender and Attitude Towards Computing Degrees

Conference Paper

Nov 2017

There is a global demand for graduates with computing skills as well as a global shortage of computing professionals, especially women. In Africa these shortages are even more critical. To resolve this problem, studies in the past have argued for increased computing usage in schools that would lead to increased interest in computing degrees. Recently computing usage in the form of mobile devices and mobile gaming has increased substantially in schools, yet in South Africa interest in studying computing at a tertiary level has not increased substantially. Hence, this paper aims to determine whether mobile and gaming usage impacts school learners’ attitude towards computer related degrees. A survey of 292 South African secondary school learners confirms low interest in computing degrees, especially by girls, as well as misperceptions of computing degrees. An IT Usage Attitude Model is proposed and validated in which mobile and gaming usage vary substantially based on gender but usage does not influence attitude towards computing degrees.

Are Nekton Communities Useful Restoration Indicators in Restored Mangroves?

Article

Full-text available

Jan 2014

We investigated: (1) the changes in the nekton community with increasing mangrove forest age (composed of 6-, 8-, 10-, 11-and 18-yr old stands); (2) the relationship among the nekton community and the mangrove vegetation, mangrove soils, and environmental variables; and (3) the nekton community as a potential indicator for evaluating progress of mangrove restoration programs. Nekton were collected using a triangular trap net (mesh size = 2 mm) with 10 m wingspan on each side (area = 43.3 m2) that was set ~ 1 m from the edge of mangrove sites facing the shoreline, for three consecutive nights (before, during and after the spring tide). The trap net was designed to catch nekton that enter mangroves at high tide and were potentially trapped as tide recedes. A total of 99 species from 52 families comprised of crabs, shrimp, squid and fi shes was recorded. Among the dominant families were Portunidae and Penaeidae (for crustaceans) and Atherinidae, Apogonidae, Hemirhamphidae, Tetraodontidae, Congridae, Sphyraenidae, Murraenidae, Ambassidae, Gerreidae, Clupeidae, Platycephalidae, Gobiidae, Mullidae and Plotosidae (for fi shes) accounting for 90% of all collected individuals. Except for the 18-yr stands, the nekton abundance and biomass from each stand did not signifi cantly varied with sampling periods. However, the nekton communities 159 PROCEEDINGS PROCEEDINGS varied signifi cantly with mangrove developmental stages. The young (< 10 yrs), intermediate (10-12 yrs), and mature (> 12 yrs) stands clustered together and were signifi cantly diff erent with the natural stands. The species composition, abundance and biomass of the nekton community were not signifi cantly correlated with mangrove stand age, vegetation and soil, but were rather signifi cantly associated with environmental variables, particularly proximity to reef and elevation. The lack of correlation suggests that nekton, as a whole, is not a useful indicator in evaluating the progress of restoring habitat functionality in planted mangroves. However, removing the fi sh assemblage and a reanalysis of other species yielded signifi cant eff ects of mangroves on nekton community. Crustaceans, particularly of the families Portunidae and Penaeidae, were useful indicators for determining the habitat functionality of planted mangroves. Species under these families (particularly crabs and shrimps) are mangrove-dependent species that have stronger affi nity to mangroves than the mangrove-transient species such as fi shes.

Rehabilitación ecológica participativa de un arroyo urbano: efectos del trasplante y manejo de macrófitas sobre la retención de nutrientes y la estructura de la comunidad perifítica.

Thesis

Full-text available

Mar 2017

Grecia Stefanía De Groot

Los arroyos que atraviesan áreas urbanas son cuerpos de agua altamente vulnerables debido a las transformaciones que el ser humano imprime sobre ellos para adecuarlos a un determinado uso cotidiano. Esto provoca un desequilibrio en la dinámica del sistema ecológico al alterar su morfología, la estructura y diversidad de las comunidades biológicas que lo habitan y las funciones ecológicas que desempeñan. Al mismo tiempo, la transformación de los sistemas lóticos trae aparejada una pérdida en distintos aspectos ecológicos percibidos por el ser humano como beneficios (bienes y servicios ecosistémicos) para mejorar su calidad de vida. La creciente preocupación por mejorar el estado de ríos y arroyos urbanos ha propiciado el desarrollo de numerosos proyectos de rehabilitación. En este trabajo hemos abordado la rehabilitación de un tramo del arroyo San Francisco (Claypole, provincia de Buenos Aires) mediante el manejo de la vegetación riparia y la re-inserción de macrófitas nativas, aplicando un enfoque socio-ecológico y de Investigación-Acción Participativa (IAP). Trabajamos junto con una cuadrilla del barrio, abocada a la limpieza y mantenimiento del arroyo, bajo el precepto de que un abordaje participativo y comunitario que incluya a todos los actores involucrados en la toma de decisiones es un elemento fundamental para garantizar el éxito en la implementación de un plan de rehabilitación a largo plazo. Utilizando un diseño BACIPS asimétrico (Before-After Control-Impact Paired Series) se evaluó el efecto de la intervención sobre la cobertura y riqueza de macrófitas, sobre la concentración y retención neta a nivel de tramo de los principales nutrientes disueltos, y sobre la estructura y función de las comunidades algales perifíticas mediante el estudio de variables de masa y la identificación de los grupos funcionales principales. El abordaje socio-ecológico de la problemática ambiental permitió identificar los problemas que afectaban la calidad del arroyo, así como las valoraciones personales que conllevaba la rehabilitación de ese curso de agua para los integrantes de la cuadrilla, poniendo de manifiesto la importancia sanitaria y eco-comunitaria por sobre el valor netamente estético. La supervivencia de las macrófitas trasplantadas alcanzó un 30% del número de parches trasplantados tres meses después de la intervención, con un aumento sostenido de la riqueza en el tramo intervenido. Sin embargo, no se observó un efecto neto sobre la retención de los principales nutrientes en el arroyo ni en la turbidez del cuerpo de agua. El empleo del perifiton como indicador de cambios en el arroyo permitió detectar un potencial efecto de la intervención. Se registraron variaciones en la comunidad algal perifítica, con un aumento significativo en su biomasa y un recambio en los grupos funcionales. Este proyecto representa una experiencia de integración de saberes y de vinculación de la investigación científica con los problemas de la sociedad desde un enfoque participativo y transversal, con el compromiso de aportar al fortalecimiento de las organizaciones populares para una mejora en el hábitat urbano y las condiciones de vida de la población.

Weather-Centric Rangeland Revegetation Planning

Article

Aug 2017

Invasive annual weeds negatively impact ecosystem services and pose a major conservation threat on semiarid rangelands throughout the western United States. Rehabilitation of these rangelands is challenging due to interannual climate and subseasonal weather variability that impacts seed germination, seedling survival and establishment, annual weed dynamics, wildfire frequency, and soil stability. Rehabilitation and restoration outcomes could be improved by adopting a weather-centric approach that uses the full spectrum of available site-specific weather information from historical observations, seasonal climate forecasts, and climate-change projections. Climate data can be used retrospectively to interpret success or failure of past seedings by describing seasonal and longer-term patterns of environmental variability subsequent to planting. A more detailed evaluation of weather impacts on site conditions may yield more flexible adaptive-management strategies for rangeland restoration and rehabilitation, as well as provide estimates of transition probabilities between desirable and undesirable vegetation states. Skillful seasonal climate forecasts could greatly improve the cost efficiency of management treatments by limiting revegetation activities to time periods where forecasts suggest higher probabilities of successful seedling establishment. Climate-change projections are key to the application of current environmental models for development of mitigation and adaptation strategies and for management practices that require a multidecadal planning horizon. Adoption of new weather technology will require collaboration between land managers and revegetation specialists and modifications to the way we currently plan and conduct rangeland rehabilitation and restoration in the Intermountain West.

La restauración ecológica clásica y los retos de la actualidad: La migración asistida como estrategia de adaptación al cambio climático

Article

Full-text available

Jul 2017

Ecological restoration is a very active area in ecology and of great importance for ecosystems management. Despite of being a relatively young discipline, the classical concepts of restoration seem, at present, impractical considering the great challenges generated by modification and destruction of ecosystems. This is due to anthropic activities (deforestation, change of land use, pollution) and global climate change. In the classic definition of restoration, the objective is to recover the degraded ecosystem to the same conditions of a historical reference state. However, nowadays the ecosystems return to a state prior to the disturbances seems unviable, because the thresholds of resilience have already been overcome. Additionally, climate change is causing environmental changes at an unprecedented rate. For this reason, ecological restoration needs to unite efforts of diverse actors to recover ecosystems that can be sustainable and functional in the future, where the species could be able to tolerate the environmental conditions that will exist in the long term. Assisted migration has been proposed as a conservation strategy; it is defined as the translocation of species to new locations outside their known range of distribution. In the current context of loss of diversity and ecosystems, this strategy could be fundamental for the formation of new communities that can later become novel ecosystems where species that are fundamental to the dynamics of ecosystems can persist and, at the same time, recover function, structure and resilience.

Restauración experimental

Article

Full-text available

Jan 2014

Large-scale ecological restoration generally employs un-replicated trial and error to re-create habitats destroyed or degraded by human activity. Trial and error follows a management plan that employs the "best available practice" for each habitat type; adaptive management reflecting experience subsequently corrects errors. The process is slow because each restoration is often well-advanced before adjustments are attempted. Rare are simultaneous replicated trials during the initial restoration or corrective process. "Systemic experimental restoration" would design replicated planting or management contrasts at the outset of large-scale public and commercial restorations. Alternative treatments create mosaics of different manifestations of a community within a mosaic of habitat types. Replicated contrasts within habitats allow the inference of cause and effect of success and failure on scales of communities, landscapes and ecosystems. For the long-term development of restoration ecology as a science, semi-natural communities of known contrasting histories will be important to encourage managers or investigators to create additional projects beyond explicit management or scientific objectives of an initial management plan. By consciously, integrating heterogeneity throughout restoration management plans, systemic mosaics of treatments within and between habitats, would facilitate multiple habitat responses to unpredictable changes in climate and land use.

Restoring Sage-grouse nesting habitat through removal of early successional conifer

Article

May 2017
RESTOR ECOL

Better living through conifer removal: A demographic analysis of sage-grouse vital rates

Article

Full-text available

Mar 2017
PLOS ONE

Sagebrush (Artemisia spp.) obligate wildlife species such as the imperiled greater sage-grouse (Centrocercus urophasianus) face numerous threats including altered ecosystem processes that have led to conifer expansion into shrub-steppe. Conifer removal is accelerating despite a lack of empirical evidence on grouse population response. Using a before-after-control-impact design at the landscape scale, we evaluated effects of conifer removal on two important demographic parameters, annual survival of females and nest survival, by monitoring 219 female sage-grouse and 225 nests in the northern Great Basin from 2010 to 2014. Estimates from the best treatment models showed positive trends in the treatment area relative to the control area resulting in an increase of 6.6% annual female survival and 18.8% nest survival relative to the control area by 2014. Using stochastic simulations of our estimates and published demographics, we estimated a 25% increase in the population growth rate in the treatment area relative to the control area. This is the first study to link sage-grouse demographics with conifer removal and supports recommendations to actively manage conifer expansion for sage-grouse conservation. Sage-grouse have become a primary catalyst for conservation funding to address conifer expansion in the West, and these findings have important implications for other ecosystem services being generated on the wings of species conservation.

Ecological Restoration: Moving Forward Using Lessons Learned: Introduction

Chapter

Jun 2023

As we move into the second decade of the twentieth-first century, it is impossible to deny that the ecosphere of our planet is in dire trouble from a range of biotic and abiotic pressures, many of which are widely accepted to continue into the indefinite future. While human activity has unarguably altered the natural world for millennia, the past 150 years or so have seen a significant increase in the natural resources required to support our way of life, the extraction of which has been to the detriment of our natural world. It is also increasingly apparent that human health and well-being are inextricably linked to having a healthy natural world, and that restoring and repairing our planet is therefore of critical and urgent importance. In addition, it is apparent that despite the increasing mobilization and utilization of our natural resources, we still face serious national and international challenges and inequalities. The United Nations now identifies 23 issues of pressing global concern (https://www.un.org/en/global-issues), including population growth, climate change and food security issues. Of the global population of 7 billion people, there are currently some 736 million people who exist in extreme poverty (World Bank, https://blogs.worldbank.org/opendata/half-world-s-poor-live-just-5-countries?cid=ECR_TT_‌world‌bank_EN_EXT), with many more millions struggling with poor sanitation, lack of potable water, limited education and little food security.

Missing in action: Reference sites

Article

Jun 2023
ECOL ENG

R. Eugene Turner

Spatial Variation in Lizard Communities in the Tucson Basin 2010-2020 and Implications for Riparian Conservation and Management

Technical Report

Full-text available

Jul 2021

The acceptable range of variation within the desirable stable state as a measure of restoration success

Article

Sep 2022

It is standard practice to compare the status of performance indicators between restoration and reference sites to monitor restoration progress and demonstrate restoration success. However, standard methods for defining the reference ecosystem, selecting reference sites, and measuring success are surprisingly lacking. Our study develops these methods based on the acceptable range of variation (ARV) within the desirable stable (reference) state as a measure of restoration success. The method: (i) constrains application to the contemporary landscape to avoid the problematic historical range of variation concept and idealised restoration targets; (ii) acknowledges the theory of alternative stable states and ecosystem dynamics and posits that the reference ecosystem should be clearly defined as a desirable stable (reference) state; and (iii) shows that identifying an acceptable thematic (classification) scale and an acceptable management timeframe is essential to defining the desirable stable (reference) state. We present two approaches to calculating an ARV and a simulation method to explore reference site replication sufficiency. We apply the methods to two contrasting Australian restoration case studies and recommend that routine adoption of these methods would make a significant contribution to the science and practice of restoration ecology and to the assessment of restoration success. This article is protected by copyright. All rights reserved.

Assessment of typhoon impacts and post-typhoon recovery in Philippine mangroves: lessons and challenges for adaptive management

Chapter

Jan 2021

Sev Salmo

The extent and state of ecosystem health of Philippine mangroves are affected by the occurrences of typhoons (ca. 20 per year). While severe damages (and sometimes even total forest collapse) are commonly reported, there are some cases where mangroves are less damaged and easily recovered implying that some mangroves are either highly vulnerable or resilient. Most studies on effects of typhoons in mangroves (including post-typhoon recovery) are mainly focused on vegetation but rarely on changes in sediment and faunal composition and activities. Also, these studies are mostly short-term and rapid (<1 year) with suboptimal experimental designs because of the lack of baseline data and systematic assessment. In this study, a 15-year synthesis of impacts of typhoon and post-typhoon recovery in selected mangrove sites in the Philippines was discussed and compared with other typhoon-disturbed tropical/subtropical mangroves. The study covered pre- and post-typhoon changes in vegetation, sediment, and faunal assemblages and activities including the assessment of possible recovery and identification of recovery indicators. The study provides an overview of interrelationships of vegetation, sediment (including nutrients), and faunal assemblages and activities as a more integrative approach in damage and recovery assessments. Lastly, the implications of the study on research needs (e.g., systematic and sustained monitoring) and policy and management programs (e.g., effective conservation and restoration programs) for Philippine mangroves were discussed.

Spatiotemporal trends in crop yields, yield variability, and yield gaps across the USA

Article

May 2020

Future crop yield increases are unlikely to keep pace with the dietary needs of a global human population expected to reach nine billion by 2050. This study used United States Department of Agriculture county‐level yield data and autoregressive moving‐average models to examine how changes in maize (Zea mays L.), soybean (Glycine max L.), and winter wheat (Triticum aestivum L.) yields, temporal variability in yields, and yield gaps have varied across space and time from 1970–2017. The majority of county‐level yields have increased linearly, although the increases in wheat lag behind corn and soybean. Where trends were nonlinear, accelerating yields were found in more mesic regions east of the Great Plains, and decelerating yields were found in the drier central and western United States. Mean crop yields were positively correlated with rate of yield increase and negatively correlated with interannual variability. Hotspots were identified in Minnesota, Iowa, Illinois, Nebraska, and some West Coast states where crop yields are currently the largest, have the lowest yield gaps, and since 1970, have had the highest rates of change and/or are experiencing an acceleration of annual yield gains. Across all crop types, the counties with the lowest average yields, highest yield gaps, lowest rates of yield increase over time, and/or deceleration in yield increases were predominantly found in the central United States, including the Dakotas, Kansas, Oklahoma, and Texas. Regions of greatest performance generally have fertile soils, plentiful growing season rainfall, and optimal growing season length and temperatures, or are benefitting from irrigation.

Evaluating outcomes of restoration ecology projects on limited budgets: assessment of variation in sampling intensity and sampling frequency for four habitat types: Evaluating outcomes of restoration projects

Article

Jul 2018

While best practices for evaluating restoration ecology projects are emerging rapidly, budget constraints often limit post‐restoration monitoring, which emphasizes the need for practical and efficient monitoring strategies. We examined the post‐restoration outcome for an ENGO (Nature Conservancy of Canada) project, to assess retroactively how variation in intensity and frequency of sampling would have affected estimates of plant species composition, diversity and richness over time. The project restored four habitat types (mesic forest, oak woodland, wet meadow and sand barren) using sculptured seeding of tallgrass prairie and woody species. Species level plant cover was monitored annually for 10 years in 168 2×2 m quadrats. We performed randomization tests to examine estimates of species diversity and richness as a function of the number of quadrats sampled, and assessed the necessity of annual sampling for describing changes in species composition and successional trajectories. The randomization tests revealed that sampling 10‐17 quadrats, depending on habitat type, was sufficient to obtain estimates of species diversity that were at least 95% of values obtained from the whole data set. Species richness as a function of number of quadrats sampled did not plateau, which suggests that rather than increasing the number of sampling quadrats, richness could be estimated more efficiently using non‐quadrat based sampling techniques. Non‐metric multidimensional scaling analysis revealed that plant species composition largely stabilized by 3‐5 years post‐restoration depending on habitat type. By that time, native, seeded species dominated the restoration, and the benefits of annual sampling for tracking changes in species composition diminished. This article is protected by copyright. All rights reserved.

MEMORIAS DE LA III CONFERENCIA PANAMERICANA DE SISTEMAS DE HUMEDALES PARA EL TRATAMIENTO Y MEJORAMIENTO DE LA CALIDAD DEL AGUA

Book

Full-text available

May 2016

Effect of hydraulic operation mode on removal efficiency of constructed wetlands planted with Cyperus ligularis and Echinochola colonum

Chapter

Full-text available

Jul 2016

Year-to-Year Fluctuation of the Spring Phytoplankton Bloom in South San Francisco Bay: An Example of Ecological Variability at the Land-Sea Interface

Chapter

Full-text available

Jan 1995

Estuaries are transitional ecosystems at the interface of the terrestrial and marine realms. Their unique physiographic position gives rise to large spatial variability, and to dynamic temporal variability resulting, in part, from a variety of forces and fluxes at the oceanic and terrestrial boundaries. River flow, in particular, is an important mechanism for delivering watershed-derived materials such as fresh water, sediments, and nutrients; each of these quantities in turn directly influences the physical structure and biological communities of estuaries. With this setting in mind, we consider here the general proposition that estuarine variability at the yearly time scale can be caused by annual fluctuations in river flow. We use a “long-term” (15-year) time series of phytoplankton biomass variability in South San Francisco Bay (SSFB), a lagoon-type estuary in which phytoplankton primary production is the largest source of organic carbon (Jassby et al. 1993).

Ecosystem Experiments

Article

Full-text available

Jul 1993

Detecting Periodicity in Quantitative versus Semi-Quantitative Time Series

Chapter

Full-text available

Jan 1995

Ordered categorical (or semi-quantitative) data are frequently encountered in ecology (e.g., Steen et al. 1990; Ménard et al. 1993). Researchers often resort to semi-quantitative measures (to describe abundance patterns, age or stage structures, environmental factors, etc.) to reduce processing time and/or because of financial constraints, while retaining an acceptable level of accuracy.

Nontraditional Regression Analyses

Data

Full-text available

Sep 1993

Each copy of any part of a JSTOR transmission must contain the same copyright notice that appears on the screen or printed page of such transmission. The JSTOR Archive is a trusted digital repository providing for long-term preservation and access to leading academic journals and scholarly literature from around the world. The Archive is supported by libraries, scholarly societies, publishers, and foundations. It is an initiative of JSTOR, a not-for-profit organization with a mission to help the scholarly community take advantage of advances in technology. For more information regarding JSTOR, please contact support@jstor.org.

Long-Term Ecological Studies: an Illustrated Account of Their Design, Operation, and Importance to Ecology

Article

Full-text available

Jan 1988

Environmental Impact Assessment: "Pseudoreplication" In Time?

Article

Full-text available

Aug 1986

There may be problems concerning the appropriate design of sampling programs to assess the impact upon the abundance of biological populations of, for example, the discharge of effluents into an aquatic ecosystem at a single point. Key to the resolution of these issues is correct identification of the statistical parameter of interest, which is the mean of the underlying probabilistic 'process' that produces the abundance, rather than the actual abundance itself. An appropriate sampling scheme was designed to detect the effect of the discharge upon this underlying mean. Detection of the effect of the discharge is achieved by testing whether the difference between abundances at a control site and an impact site changes once the discharge begins. -from Authors

Spatial Interpolation Errors for Monitoring Data

Article

Full-text available

Sep 1995

Separate modeling of the spatial mean field, the spatial variance field, and the space-time residual fields can give a more detailed and possibly more accurate representation of spatial interpolation errors when we have repeated observations on a fixed monitoring network. This article gives expressions for the spatial interpolation errors in terms of the statistics of the component fields, which enable us to assess the relative importance of different kinds of uncertainty. This modeling approach is applied to data of sulfur dioxide concentrations in Europe, and a comparison with neighborhood kriging is done by means of cross-validation.

A Conceptual Tool for Generating and Evaluating Ecological Hypotheses

Article

Full-text available

Jan 1995
BIOSCIENCE

Distance Sampling: Estimating Abundance of Biological Populations

Book

Full-text available

Jan 1993

This book is available for purchase, The 1993 version is available on the page at http://distancesampling.org/downloads/distancebook1993/index.html

The Design and Analysis of Research Studies

Book

May 1992

Bryan F. J. Manly

This book provides students and research workers in the biological, medical and social sciences with the statistical background needed to collect and analyse data in an intelligent and critical manner. Key examples and case studies are used to illustrate commonly encountered research problems and to explain how they may be solved or even avoided altogether. Professor Manly also presents a clear understanding of the opportunities and limitations of different research designs, as well as an introduction to some new methods of analysis that are proving increasingly popular. Topics covered include the differences between observational and experimental studies; the design of sample surveys; multiple regression and its generalizations to log-linear and logistic models; experimental and quasi-experimental designs; interrupted time series; computer intensive methods of statistical inference; and the ethical considerations of research. In the final chapter, there is a useful discussion of how the various components of a research study (including deciding on the objectives, planning, designing, and the collection and analysis of data) come together. This practical and well-structured book will be essential reading for graduate students and researchers in a wide range of disciplines, including biology, anthropology, medicine and the social sciences.

Distance Sampling

Book

Jan 1993

Multivariate Analysis in Community Ecology

Book

Feb 1982

Hugh G. Gauch

Ecologists are making increasing use of computer methods in analyzing ecological data on plant and animal communities. Ecological problems naturally involve numerous variables and numerous individuals or samples. Multivariate techniques permit the summary of large, complex sets of data and provide the means to tackle many problems that cannot be investigated experimentally because of practical restraints. Ecologists are thus enabled to group similar species and similar sample sites together, and to generate hypotheses about environmental and historical factors that affect the communities. This timely book presents a full critical description of three methodologies - direct gradient analysis, ordination, and classification - from both theoretical and practical viewpoints. Both traditional and new methods are presented. Using a wide range of illustrative examples, Hugh Gauch provides an up-to-date synthesis of this field, which will be of interest to advanced students and ecologists. These mathematical tools are also used in a wide variety of other areas, from natural resource management and agronomy to the social and political sciences.

Generalized Linear Models

Book

Jan 1983

Land Mosaics: The Ecology of Landscapes and Regions

Book

Nov 1995

Cambridge Core - Ecology and Conservation - Land Mosaics - by Richard T. T. Forman

Automated smoothing techniques for visualization and quality control of long-term environmental data

Article

Jan 1994

Data of understood quality, free from introduced errors or biases, are critical for analyses that aim to isolate subtle trends or patterns related to disturbance, succession or ecosystem evolution. As data accrue, the demand for data-driven, statistically based quality control techniques increases. A data quality control method for long-term environmental data that emphasizes statistical data visualization is described. Traditional parametric modelling is compared with semiparametric smoothing techniques using the Akaika Information Criterion (AIC) for model selection. An interface in development fits a series of parametric and semiparametric models, selects the minimum AIC fit, returns graphical output and estimates the potential intervention points. -Authors

Long-Term Studies in Ecology: Approaches and Alternatives

Book

Jan 1989

Gene E. Likens

The Cary Conferences, as we have envisaged them, are different from most scientific meetings in that they provide a forum for major issues in ecology from a more philosophical point of view. It appears to many of us that ecologists have limited opportunities to come together in small groups to address in a more philosophical way some of the major questions and issues that matter very much to the future of humankind and to us as ecologists. Moreover, we hope that the setting ofthe Mary Flagler Cary Arboretum promotes strong interaction and dis cussion between Conference participants with a minimum of distraction. We are proud to make our facilities available for such meetings, and we hope that over the years these Conferences might provide direction and leadership for the whole field of ecology. We have the broad goal of attempting to advance the field of ecology by bringing together leading ecologists and other scientists to address major issues. The first Cary Conference, in 1985, considered the status and future of ecosystem science. This first Conference was rather loosely structured but was successful in stimulating discussion, ideas, and enthusiasm (Likens et al. , 1987). The goals for this second Cary Conference in 1987 were: 1. to identify the roles of long-term studies in ecology; 2. to identify the options for study of long-term ecological phenomena; 3.

Multivariate Analysis of Ecological Communities

Article

Jan 1987

Development and refinement of the Konza Prairie LTER research information management program

Article

Jan 1994

The primary goal of the long-term ecological research programme at Konza Prairie is to understand how grazing influences biotic and ecosystem processes and patterns imposed by fire frequency over the landscape mosaic, all of which are subjected to a variable (and possibly directional) climatic regime. A vital component of the research programme has been the development of the Konza Prairie LTER Research Information Management Program with the overall objectives of assuring data integrity, providing security for the database, and facilitating use of data by the original investigator(s) as well as by future investigators. Programme development has benefited from experiences gained through various administrative changes associated with Konza Prairie, growth of the research programme on Konza Prairie (especially in the fields of remote sensing and geographical information systems (GIS)), knowledge gained from other multidisciplinary research efforts (i.e., other LTER sites and First ISLSCP (International Satellite Land Surface Climatology Project) Field Experiment (FIFE), and with changing computer technology. -from Authors

Ecosystem Experiments.

Article

Jun 1992

The fifteen contributions show the formidable difficulties inherent in predicting the consequences of ecosystem changes, noting the use but also limitations of historical records and simulation models. The way forward is envisioned as being through long-term experimental manipulation of whole ecosystems. Such experiments would not only show how whole sytems, as well as their component elements, might respond to both short- and long-term change, but would also serve as tests for simulation models. Chapters, all abstracted separately, are on: El Nino; atmosphere-forest interactions and Amazon Basin deforestation; lessons from deforestation processes in the past; desertification; acid rain and forest ecosystems; uncontrolled ecosystem experiments with inorganic and organic micropollution; whole-lake experiments at the Experimental Lakes Area; fire and stream water chemistry; acidification; wetland ecosystems; forested watershed disturbance; mathematics of complex systems; aquatic ecosystem experiments in the context of global climatic change; whole-terrestrial ecosystem experiments; available technologies for field experimentation with elevated CO2 in global change research. (See 93L/11129, 11130, 11318, 11319, 11447-11449, 11453, 12022, 12064, 12065, 12109, 12200 and 12251). -P.J.Jarvis

New methods for using diatoms and chrysophytes to infer past pH of low-alkalinity lakes: Inferring past pH in lake water

Article

Nov 1988
LIMNOL OCEANOGR

Distributions of both diatoms and chrysophytes (Mallomonadaceae) are clearly correlated with pH in low‐alkalinity lakes. Their siliceous remains are well preserved in lake sediments and have been used to infer long‐ and short‐term acidification trends. Until now, however, only diatoms have been used quantitatively. We describe new methods for inferring past pH in lake water using diatoms alone, chrysophytes alone, and the two together. We developed the equations with multiple regression analysis of diatom and chrysophyte assemblage data and pH measurements for 47 Adirondack lakes (pH range, 4.7–7.8). Correlations of measured vs. calculated values of pH yield r ² values of 0.70–0.94 and standard errors of 0.13–0.35 pH unit. The best predictive equations, especially for acidic lakes (pH < 5.5) incorporate both diatoms and chrysophytes. Major advantages of using chrysophytes in addition to diatoms in paleoecological studies are that chrysophytes are more sensitive at lower pH values (<5.0) than diatoms, are nearly all planktonic, represent a different phycological group, can be counted on the same slides as diatoms, and can be counted faster because there are fewer taxa. Stratigraphic diatom and chrysophyte data for two lake sediment cores are used to evaluate the equations. These methods are widely applicable in studies of cultural and natural acidification of low‐alkalinity lakes in many regions of the world.

Aquatic ecosystem experiments in the context of global climate change: working group report

Article

Jan 1991

J.F. Kitchell

Exphasizes scientific problems requiring the scale and understanding that can be obtained only by the power of whole-ecosystem experiments. Assessments and recommendations are presented for discrete system types but include the assumption that many important changes in aquatic systems will derive from changes in the terrestrial systems located "upstream' in the hydrologic cycle. -from Authors

Whole-lake experiments at the Experimental Lakes Area

Article

Jan 1991

D.W. Schindler

Whole lake experiments have included eutrophication; acidification; pollution with radioactive materials and trace metals; and, very recently, a beginning in food chain manipulations. ELA work has also examined the effects of watershed changes on lakes, either by deliberately modifying watersheds (for example, wetland acidifications) and the clearcutting of forests. -from Author

Metadata required to determine the fitness of spatial data for use in environmental analysis

Article

Jan 1994

N.R. Chrisman

Much of the information managed for environmental analysis has a spatial component, which is critical in integrating one source with another. Recent standards efforts around the world (particularly the US Spatial Data Transfer Standard (SDTS)) specify the kind of information (data about the data or metadata) required to evaluate the data quality of some spatial data product. The SDTS requires that a data producer provide a Data Quality Report, which includes the lineage, positional accuracy, attribute accuracy, logical consistency and completeness of the data. Many of these elements of the report can be transmitted in the form of spatial distributions. A potential user should be able to peruse the Data Quality Report and render an informed judgement about the fitness of the data for the projected use. The Vector Product Format (designed for the public domain Digital Chart of the World), when compared with SDTS, shows particular improvements in implementing the original goals of including information to evaluate fitness for use. One key element is the treatment of metadata as spatial data in their own right. -Author

Patterns of Primary Production and Herbivory in 25 North American Lake Ecosystems

Chapter

Jan 1991

The effects of nutrients and herbivory on phytoplankton biomass and production were examined, using data from 25 lakes studied for 2 to 6 years each. Variance among lakes was substantially greater than variance among years, for all physical, chemical, phytoplankton, and zooplankton variates studied. Experimentally manipulated lakes had coefficients of variation within the range exhibited by nonmanipulated lakes. Graphical, correlative, and regression analyses illustrated the significant joint effects of both nutrients and herbivory on phytoplankton biomass and production. A Bayesian analysis of sensitivity to new information showed that the statistical models for chlorophyll are quite robust. Statistical models for primary production were deemed less conclusive, because primary production was measured in fewer lakes. We provide a list of common challenges in comparative statistical analysis of ecosystems and explain their implications for our study. The major pattern apparent in our data—that summer chlorophyll responds positively to nutrients and negatively to herbivore size — is congruent with results of whole-lake experiments in which nutrients or predators were manipulated.

Importance and Justification of Long-Term Studies in Ecology

Chapter

Jan 1989

Jerry F. Franklin

Numerous, irrefutable examples of the central role that long-term studies play in ecology now exist (see, e.g., Likens, 1983; Strayer et al., 1986). There is increasing recognition that, because most important questions in ecology ultimately deal with predicting ecosystem responses, testing the correctness of ecological concepts and predictions by observing the future is essential. There are many sophisticated predictive models and general constructs, but few have actually been tested against data. In the final analysis, the most convincing validation comes only from such tests against reality.

A generic framework for evaluating complex restoration and conservation projects

Article

Jan 1991

J.J. Berger

Retrospective Studies

Chapter

Jan 1989

Margaret Bryan Davis

Are retrospective studies useful as supplements to long-term ecological studies? Can they serve as substitutes? Retrospective studies have often addressed the same sorts of problems as long-term studies. These include obtaining baseline data for comparison with modern observations, observing very slow processes, and measuring community and ecosystem responses to rare events (Strayer et al., 1986).

Locally weighted regression

Article

Jan 1988

Integration of simulation modeling and error propagation for the buffer operation in GIS

Article

Jan 1994
PHOTOGRAMM ENG REM S

Howard Veregin

This paper explores a methodology for enhancing the utility of the information derived from simulation modelling for assessing the quality of GIS derived data. The methodology is based on the integration of simulation modelling and error propagation. Using the buffer operation as an example, simulation modelling is used to derive a formal mathematical expression describing how error is propagated through the operation from the source layer to the derived buffer. This expression is based on information about the source layer that is relatively easy to obtain, and can be used in an applied environment to estimate derived buffer accuracy without the need to perform sensitivity analysis. -from Author

Nongeospatial metadata for ecology

Article

Feb 1997

Issues related to data preservation and sharing are receiving increased attention from scientific societies, funding agencies, and the broad scientific community. Ecologists, for example, are increasingly using data collected by other scientists to address questions at broader spatial, temporal, and thematic scales (e.g., global change, biodiversity, sustainability). No data set is perfect and self-explanatory. Ecologists must, therefore, rely upon a set of instructions or documentation to acquire a specific data set, determine its suitability for meeting specific research objectives, and accurately interpret results from subsequent processing, analysis, and modeling. 'Metadata' represent the set of instructions or documentation that describe the content, context, quality, structure, and accessibility of a data set. Although geospatial metadata standards have been developed and widely endorsed by the geographical science community, such standards do not yet exist for the ecological sciences. In this paper, we examine potential benefits and costs associated with developing and implementing metadata for nongeospatial ecological data. We present a set of generic metadata descriptors that could serve as the basis for a 'metadata standard' for nongeospatial ecological data. Alternative strategies for metadata implementation that meet differing organizational or investigator-specific objectives are presented. Finally, we conclude with several recommendations related to future development and implementation of ecological metadata.

Long-Term Studies in Ecology

Chapter

Jan 1989

David Tilman

The ecological world is a multi-causal system in which patterns result from the direct effects of physical factors, from intraspecific and interspecific biotic interactions, and from indirect and feedback effects of one species or system element on another. As such, there is no single, simple approach that can ever unambiguously demonstrate how or why a particular process, physical factor, or species has an effect on another element of the ecosystem. Although this chapter will critically evaluate the potential contributions of experimentation to ecological understanding, I must stress at the outset that ecological research requires a synthetic approach in which observational, experimental, and theoretical approaches are pursued in a simultaneous, coordinated, interactive manner.

Locally Weighted Regression: An Approach to Regression Analysis by Local Fitting

Article

Sep 1988

ANOVA for unbalanced data An overview

Article

Sep 1993

Ecological studies typically involve comparison of biological responses among a variety of environmental conditions. When the response variables have continuous distributions and the conditions are discrete, whether inherently or by design, then it is appropriate to analyze the data using analysis of variance (ANOVA). When data conform to a complete, balanced design (equal numbers of observations in each experimental treatment), it is straightforward to conduct an ANOVA, particularly with the aid of the numerous statistical computing packages that are available. Interpretation of an ANOVA of balanced data is also unambiguous. Unfortunately, for a variety of reasons, it is rare that a practicing ecologist embarks on an analysis of data that are completely balanced. Regardless of its cause, lack of balance necessitates care in the analysis and interpretation. In this paper, our aim is to provide an overview of the consequences of lack of balance and to give some guidelines to analyzing unbalanced data for models involving fixed effects. Our treatment is necessarily cursory and will not substitute for training available from a sequence of courses in mathematical statistics and linear models. It is intended to introduce the reader to the main issues and to the extensive statistical literature that deals with them.

Detecting Changes in Ecological Time Series

Article

Dec 1990

Some practical techniques are discussed for analyzing time series whose statistical properties are changing with time. We first consider how principal component analysis can reduce the multidimensional nature of certain series and, in particular, apply this technique to the analysis of changing seasonal patterns. Discussions of trend, changes in oscillatory behavior, and "unusual" events follow. The problem of making inferences regarding causation is briefly considered. We conclude with a call for flexibility in approach.

Ecological Experiments: Purpose, Design and Execution.

Article

Apr 1991

The Design and Analysis of Research Studies

Article

Dec 1993

This book provides research workers with the statistical background needed in order to collect and analyze data in an intelligent and critical manner. Key examples and case studies are used to illustrate commonly encountered research problems and to explain how they may be solved or even avoided altogether. Professor Manly also presents a clear understanding of the opportunities and limitations of different research designs, as well as an introduction to some new methods of analysis that are proving increasingly popular. Topics covered include: the differences between observational and experimental studies, the design of sample surveys, multiple regression, interrupted time series, computer intensive statistics, and the ethical considerations of research. In the final chapter, there is a discussion of how the various components of a research study come together.

Applied Logistic Regression Analysis

Article

Aug 1992

The Method of Multiple Working Hypotheses

Article

Jan 1897

T. C. Chamberlin

2043

Biological Response to Climate Change: An Agenda for Research

Article

May 1991

H. A. Mooney

Our knowledge of the structure and functioning of terrestrial ecosystems on a global scale is not developed to a sufficient degree to understand--much less predict--the consequences of climate change either on the systems themselves or on subsequent atmospheric interactions. In many regards we have lagged behind the atmospheric scientists, and to a certain degree the oceanographers, in establishing a global understanding of the dynamics of our respective systems. This is due in part to the inherently greater complexity of biotic systems, but also to the lack of appropriate tools to measure regional biotic processes. These tools are now becoming available and with them a better understanding of terrestrial and atmospheric interactions. Even as these capabilities become a reality we must be realistic in recognizing that we have so far to go along the road to understanding that useful predictive capacity may elude us for a long time to come. What we need to do is act on the recommendations that have been emerging over the past few years and develop a global program to document more precisely the distribution, structure, and quantity of the earth's biotic systems, their principal functional properties, and--most difficult of all--their changing nature. In order to do this we will have to: (1) perfect some of the emerging new tools for assessing these properties, (2) fill some of the gaps in our knowledge about the relevant processes, and (3) establish an international network of long-term observations and large-scale ecosystem manipulations. We have been aware of these needs and shortcomings for some time and we must move from plans to concerted international action.

Multivariate Analysis of Ecological Communities

Article

Jan 1988

Generalized Linear Models

Article

Dec 1990

Scientific Information Systems: A Conceptual Framework

Chapter

Jan 1994

A conceptual framework for the design, implementation, and operation of scientific information systems has been developed. This framework is based on experience with focused field experiments, long-term data archiving, and data publication. The elements of the framework include management and organizational constraints, the requirements of the scientific community, the flow of data from source to archive, and resource requirements. Examples of these principles, drawn from successful information systems experience with the FIFE Information System and the Pilot Land Data System, are discussed.

Quantitative Methods in Landscape Ecology

Book

Jan 1991

Quantitatively Evaluating Restoration Experiments: Research Design, Statistical Analysis, and Data Management Considerations

Abstract

No full-text available