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1.
Science ; 384(6694): 453-458, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38662833

RESUMEN

Governments recently adopted new global targets to halt and reverse the loss of biodiversity. It is therefore crucial to understand the outcomes of conservation actions. We conducted a global meta-analysis of 186 studies (including 665 trials) that measured biodiversity over time and compared outcomes under conservation action with a suitable counterfactual of no action. We find that in two-thirds of cases, conservation either improved the state of biodiversity or at least slowed declines. Specifically, we find that interventions targeted at species and ecosystems, such as invasive species control, habitat loss reduction and restoration, protected areas, and sustainable management, are highly effective and have large effect sizes. This provides the strongest evidence to date that conservation actions are successful but require transformational scaling up to meet global targets.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Extinción Biológica , Especies Introducidas , Animales , Ecosistema
2.
Astrobiology ; 24(3): 318-327, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38350125

RESUMEN

Organisms act stochastically. A not uncommon view in the ecological literature is that this is mainly due to the observer having insufficient information or a stochastic environment-and not partly because organisms themselves respond with inherent unpredictability. In this study, I compile the evidence that contradicts that view. Organisms generate uncertainty internally, which results in irreducible stochastic responses. I consider why: for instance, stochastic responses are associated with greater adaptability to changing environments and resource availability. Over longer timescales, biologically generated uncertainty influences behavior, evolution, and macroecological processes. Indeed, it could be stated that organisms are systems defined by the internal generation, magnification, and record-keeping of uncertainty as inputs to responses. Important practical implications arise if organisms can indeed be defined by an association with specific classes of inherent uncertainty: not least that isolating those signatures then provides a potential means for detecting life, for considering the forms that life could theoretically take, and for exploring the wider limits to how life might become distributed. These are all fundamental goals in astrobiology.


Asunto(s)
Incertidumbre , Procesos Estocásticos
4.
Conserv Biol ; 38(2): e14198, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37811729

RESUMEN

Biodiversity compensation policies have emerged around the world to address the ecological harms of infrastructure expansion, but historically compliance is weak. The Westminster government is introducing a requirement that new infrastructure developments in England demonstrate they achieve a biodiversity net gain (BNG). We sought to determine the magnitude of the effects of governance gaps and regulator capacity constraints on the policy's potential biodiversity impacts. We collated BNG information from all new major developments across six early-adopter councils from 2020 to 2022. We quantified the proportion of the biodiversity outcomes promised under BNG at risk of noncompliance, explored the variation in strategies used to meet developers' biodiversity liabilities, and quantified the occurrence of simple errors in the biodiversity metric calculations. For large developments and energy infrastructure, biodiversity liabilities frequently met within the projects' development footprint. For small developments, the purchase of offsets was most common. We estimated that 27% of all biodiversity units fell into governance gaps that exposed them to a high risk of noncompliance because they were associated with better-condition habitats delivered on-site that were unlikely to be monitored or enforced. More robust governance mechanisms (e.g., practical mechanisms for monitoring and enforcement) would help ensure the delivery of this biodiversity on-site. Alternatively, more biodiversity gains could be delivered through off-site biodiversity offsetting. For the latter case, we estimated that the demand for offsets could rise by a factor of 4; this would substantially increase the financial contributions from developers for conservation activities on private land. Twenty-one percent of development applications contained a simple recurring error in their BNG calculations. One-half of these applications were approved by councils, which may indicate under-resourcing in council development assessments. Our findings demonstrate that resourcing and governance shortfalls risk undermining the policy's effectiveness.


sObtención de la ganancia neta de biodiversidad mediante el abordaje de las lagunas en la gobernanza que apuntalan las políticas de compensación ecológica Resumen Las políticas de compensación por biodiversidad han surgido en todo el mundo para abordar los daños ecológicos de la expansión infraestructural, aunque su cumplimiento histórico es deficiente. El gobierno de Westminster está introduciendo un requerimiento para que las nuevas infraestructuras en Inglaterra demuestren que obtienen una ganancia neta de biodiversidad (GNB). Buscamos determinar la magnitud que tienen los efectos de las lagunas de gobernanza y las restricciones de la capacidad regulatoria sobre los impactos potenciales de la política en la biodiversidad. Recopilamos la información de GNB de todos los desarrollos principales en seis consejos pioneros entre 2020 y 2022. Cuantificamos la proporción de los resultados de biodiversidad prometidos bajo la GNB en riesgo de no ser cumplidos, exploramos la variación de estrategias usadas para cumplir las responsabilidades de biodiversidad de los desarrolladores y cuantificamos la incidencia de errores simples en el cálculo de las medidas de biodiversidad. En los grandes desarrollos y en la infraestructura energética, las responsabilidades de biodiversidad fueron cumplidas con frecuencia dentro de la huella de desarrollo del proyecto. En los pequeños desarrollos, la compra de compensaciones fue más común. Estimamos que el 27% de todas las unidades de biodiversidad caen dentro de las lagunas de gobernanza que las exponen a un riesgo elevado de no ser cumplidas porque se asociaban con hábitats en mejores condiciones entregados en sitios con mayor probabilidad de no ser monitoreados o implementados. Tener mecanismos de gobernanza más robustos (mecanismos prácticos para el monitoreo y la implementación) ayudaría a asegurar la entrega de esta biodiversidad en sitio. Como alternativa, una mayor ganancia de biodiversidad podría entregarse a través de las compensaciones de biodiversidad fuera de sitio. Para el último caso, estimamos que la demanda de compensaciones podría aumentar en un factor de 4; esto incrementaría sustancialmente las contribuciones económicas de los desarrolladores para las actividades de conservación en suelo privado. El 21% de las aplicaciones de desarrollo incluyeron un error simple recurrente en los cálculos de su GNB. La mitad de estas aplicaciones fueron aprobadas por consejos, lo que podría indicar una escasez de evaluaciones en los consejos. Nuestros resultados demuestran que la insuficiencia en la dotación de recursos y la de gobernanza arriesga la efectividad de las políticas.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Ecosistema , Políticas , Inglaterra
6.
Glob Chang Biol ; 29(15): 4397-4411, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37300408

RESUMEN

Biodiversity offsetting is a globally influential policy mechanism for reconciling trade-offs between development and biodiversity loss. However, there is little robust evidence of its effectiveness. We evaluated the outcomes of a jurisdictional offsetting policy (Victoria, Australia). Offsets under Victoria's Native Vegetation Framework (2002-2013) aimed to prevent loss and degradation of remnant vegetation, and generate gains in vegetation extent and quality. We categorised offsets into those with near-complete baseline woody vegetation cover ("avoided loss", 2702 ha) and with incomplete cover ("regeneration", 501 ha), and evaluated impacts on woody vegetation extent from 2008 to 2018. We used two approaches to estimate the counterfactual. First, we used statistical matching on biophysical covariates: a common approach in conservation impact evaluation, but which risks ignoring potentially important psychosocial confounders. Second, we compared changes in offsets with changes in sites that were not offsets for the study duration but were later enrolled as offsets, to partially account for self-selection bias (where landholders enrolling land may have shared characteristics affecting how they manage land). Matching on biophysical covariates, we estimated that regeneration offsets increased woody vegetation extent by 1.9%-3.6%/year more than non-offset sites (138-180 ha from 2008 to 2018) but this effect weakened with the second approach (0.3%-1.9%/year more than non-offset sites; 19-97 ha from 2008 to 2018) and disappeared when a single outlier land parcel was removed. Neither approach detected any impact of avoided loss offsets. We cannot conclusively demonstrate whether the policy goal of 'net gain' (NG) was achieved because of data limitations. However, given our evidence that the majority of increases in woody vegetation extent were not additional (would have happened without the scheme), a NG outcome seems unlikely. The results highlight the importance of considering self-selection bias in the design and evaluation of regulatory biodiversity offsetting policy, and the challenges of conducting robust impact evaluations of jurisdictional biodiversity offsetting policies.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Conservación de los Recursos Naturales/métodos , Madera , Motivación , Victoria , Ecosistema
9.
Conserv Biol ; 35(2): 510-521, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-32538478

RESUMEN

When evaluating the impact of a biodiversity conservation intervention, a counterfactual is typically needed. Counterfactuals are possible alternative system trajectories in the absence of an intervention. Comparing observed outcomes against the chosen counterfactual allows the impact (change attributable to the intervention) to be determined. Because counterfactuals by definition never occur, they must be estimated. Sometimes, there may be many plausible counterfactuals, including various drivers of biodiversity change and defined on a range of spatial or temporal scales. Here, we posit that, by definition, conservation interventions always take place in social-ecological systems (SES) (i.e., ecological systems integrated with human actors). Evaluating the impact of an intervention in an SES, therefore, means taking into account the counterfactuals assumed by different human actors. Use of different counterfactuals by different actors will give rise to perceived differences in the impacts of interventions, which may lead to disagreement about its success or the effectiveness of the underlying approach. Despite that there are biophysical biodiversity trends, it is often true that no single counterfactual is definitively the right one for conservation assessment, so multiple evaluations of intervention efficacy could be considered justifiable. Therefore, we propose calculating the sum of perceived differences, which captures the range of impact estimates associated with different actors in a given SES. The sum of perceived differences gives some indication of how closely actors in an SES agree on the impacts of an intervention. We applied the concept of perceived differences to a set of global, national, and regional case studies (e.g., global realization of Aichi Target 11 for marine protected areas, effect of biodiversity offsetting on vegetation condition in Australia, and influence of conservation measures on an endangered ungulate in Central Asia). We explored approaches for minimizing the sum, including a combination of negotiation and structured decision making, careful alignment of expectations on scope and measurement, and explicit recognition of any intractable differences between stakeholders.


Reconciliación de Múltiples Hipótesis de Contraste al Evaluar el Impacto de la Conservación de la Biodiversidad en los Sistemas Socio-Ecológicos Resumen Cuando se evalúa el impacto de una intervención de conservación de la biodiversidad, generalmente se requiere una hipótesis de contraste. Las hipótesis de contraste son las posibles trayectorias alternativas del sistema en ausencia de una intervención. La comparación de los resultados observados con la hipótesis de contraste elegida permite que se determine el impacto (cambio atribuible a la intervención). Ya que las hipótesis de contraste por definición nunca ocurren, éstas deben ser estimadas. En algunos casos es posible que existan muchas hipótesis de contraste, incluyendo a muchos conductores del cambio en la biodiversidad, y que estén definidas bajo una gama de escalas espaciales o temporales. En este artículo planteamos que, por definición, las intervenciones de conservación siempre ocurren en sistemas socioecológicos (SES) (es decir, sistemas ecológicos integrados con actores humanos). Por lo tanto, la evaluación del impacto de una intervención en un SES implica la consideración de las hipótesis de contraste asumidas por los diferentes actores humanos. El uso de diferentes hipótesis de contraste por los diferentes actores hará que surjan diferencias percibidas en los impactos de las intervenciones, lo que puede llegar a discrepancias sobre su éxito o sobre la efectividad de la estrategia subyacente. A pesar de que existen tendencias biofísicas de la biodiversidad, con frecuencia es cierto que no hay una sola hipótesis de contraste que sea correcta de manera definitiva para la evaluación de la conservación, por lo que múltiples evaluaciones de la eficiencia de la intervención podrían considerarse como justificables. Así, proponemos que se calcule la suma de las diferencias percibidas, la cual captura la gama de las estimaciones de impacto asociadas con diferentes actores en un SES dado. La suma de las diferencias percibidas nos da algún tipo de indicación sobre cuán de acuerdo están los actores de un SES sobre los impactos de una intervención. Aplicamos el concepto de diferencias percibidas a un conjunto de estudios de caso mundiales, nacionales y regionales (p. ej.: la realización mundial del Objetivo Aichi 11 para las áreas marinas protegidas, el efecto de la compensación de la biodiversidad sobre las condiciones botánicas en Australia y la influencia de las medidas de conservación sobre un ungulado en peligro en Asia central). Exploramos las estrategias para minimizar la suma, incluyendo una combinación de negociación y toma estructurada de decisiones, la alineación cuidadosa de las expectativas sobre el enfoque y la medida y el reconocimiento explícito de cualquier diferencia intratable entre los actores sociales.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Australia , Ecosistema , Humanos
11.
Nat Ecol Evol ; 4(1): 46-49, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31844192

RESUMEN

A global goal of no net loss of natural ecosystems or better has recently been proposed, but such a goal would require equitable translation to country-level contributions. Given the wide variation in ecosystem depletion, these could vary from net gain (for countries where restoration is needed), to managed net loss (in rare circumstances where natural ecosystems remain extensive and human development imperative is greatest). National contributions and international support for implementation also must consider non-area targets (for example, for threatened species) and socioeconomic factors such as the capacity to conserve and the imperative for human development.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Animales , Especies en Peligro de Extinción , Humanos
12.
Conserv Biol ; 33(1): 76-87, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30070731

RESUMEN

Governments, businesses, and lenders worldwide are adopting an objective of no net loss (NNL) of biodiversity that is often partly achieved through biodiversity offsetting within a hierarchy of mitigation actions. Offsets aim to balance residual losses of biodiversity caused by development in one location with commensurate gains at another. Although ecological challenges to achieve NNL are debated, the associated gains and losses for local stakeholders have received less attention. International best practice calls for offsets to make people no worse off than before implementation of the project, but there is a lack of clarity concerning how to achieve this with regard to people's use and nonuse values for biodiversity, especially given the inevitable trade-offs when compensating biodiversity losses with gains elsewhere. This is particularly challenging for countries where poor people depend on natural resources. Badly planned offsets can exacerbate poverty, and development and offset impacts can vary across spatial-temporal scales and by location, gender, and livelihood. We conceptualize the no-worse-off principle in the context of NNL of biodiversity, by exploring for whom and how the principle can be achieved. Changes in the spatial and temporal distribution of biodiversity-related social impacts of a development and its associated offset can lead to social inequity and negatively impact people's well-being. The level of aggregation (regional, village, interest group, household, and individual) at which these social impacts are measured and balanced can again exacerbate inequity in a system. We propose that a determination that people are no worse off, and preferably better off, after a development and biodiversity offset project than they were before the project should be based on the perceptions of project-affected people (assessed at an appropriate level of aggregation); that their well-being associated with biodiversity losses and gains should be at least as good as it was before the project; and that this level of well-being should be maintained throughout the project life cycle. Employing this principle could help ensure people are no worse off as a result of interventions to achieve biodiversity NNL.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Ecología , Recursos Naturales
13.
Conserv Biol ; 33(2): 307-318, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30009509

RESUMEN

Biodiversity declines threaten the sustainability of global economies and societies. Acknowledging this, businesses are beginning to make commitments to account for and mitigate their influence on biodiversity and report this in sustainability reports. We assessed the top 100 of the 2016 Fortune 500 Global companies' (the Fortune 100) sustainability reports to gauge the current state of corporate biodiversity accountability. Almost half (49) of the Fortune 100 mentioned biodiversity in reports, and 31 made clear biodiversity commitments, of which only 5 were specific, measureable, and time bound. A variety of biodiversity-related activities were disclosed (e.g., managing impacts, restoring biodiversity, and investing in biodiversity), but only 9 companies provided quantitative indicators to verify the magnitude of their activities (e.g., area of habitat restored). No companies reported quantitative biodiversity outcomes, making it difficult to determine whether business actions were of sufficient magnitude to address impacts and were achieving positive outcomes for nature. Conservation science can advance approaches to corporate biodiversity accountability by helping businesses make science-based biodiversity commitments, develop meaningful indicators, and select more targeted activities to address business impacts. With the biodiversity policy super year of 2020 rapidly approaching, now is the time for conservation scientists to engage with and support businesses in playing a critical role in setting the new agenda for a sustainable future for the planet with biodiversity at its heart.


Uso de la Ciencia de la Conservación para Potenciar la Responsabilidad Corporativa hacia la Biodiversidad Resumen Las declinaciones de la biodiversidad amenazan a la sustentabilidad de las sociedades y economías globales. Los negocios han reconocido esto y han comenzado a comprometerse a mitigar y a responsabilizarse por su influencia sobre la biodiversidad y a reportar esto en informes sobre sustentabilidad. Evaluamos los informes sobre sustentabilidad de las 100 mejores compañías del reporte Fortune 500 Global del 2016 (el Fortune 100) para estimar el estado actual de la responsabilidad corporativa hacia la biodiversidad. Casi la mitad (49) del Fortune 100 mencionó a la biodiversidad en sus informes, y 31 dejaron claro sus compromisos con la biodiversidad, de los cuales sólo cinco fueron específicos, medibles y limitados por tiempo. Se divulgó una variedad de actividades relacionadas con la biodiversidad (p. ej.: manejo de impactos, restauración de la biodiversidad e inversión en la biodiversidad). Pero sólo nueve compañías proporcionaron indicadores cuantitativos para verificar la magnitud de sus actividades (p. ej.: área del hábitat restaurado). Ninguna compañía reportó resultados cuantitativos con respecto a la biodiversidad, lo que complica la determinación de si las acciones de las empresas fueron de una magnitud suficiente para tratar los impactos y si se están logrando resultados positivos para la naturaleza. La ciencia de la conservación puede potenciar los métodos para la responsabilidad corporativa hacia la biodiversidad ayudando a las empresas a realizar compromisos con la biodiversidad basados en la ciencia, desarrollar indicadores significativos y seleccionar actividades más enfocadas para tratar los impactos de las empresas. Con la rápida aproximación del súper año para la biodiversidad, el 2020, ahora es el momento para que los científicos de la conservación apoyen y se comprometan con las empresas para tener un papel significativo en el establecimiento de una nueva agenda con la biodiversidad como núcleo para el futuro sustentable del planeta.


Asunto(s)
Biodiversidad , Conservación de los Recursos Naturales , Ecosistema , Organizaciones , Responsabilidad Social
14.
Science ; 360(6394): 1195-1196, 2018 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-29903968
15.
Bioscience ; 68(5): 336-347, 2018 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-29731513

RESUMEN

Efforts to conserve biodiversity comprise a patchwork of international goals, national-level plans, and local interventions that, overall, are failing. We discuss the potential utility of applying the mitigation hierarchy, widely used during economic development activities, to all negative human impacts on biodiversity. Evaluating all biodiversity losses and gains through the mitigation hierarchy could help prioritize consideration of conservation goals and drive the empirical evaluation of conservation investments through the explicit consideration of counterfactual trends and ecosystem dynamics across scales. We explore the challenges in using this framework to achieve global conservation goals, including operationalization and monitoring and compliance, and we discuss solutions and research priorities. The mitigation hierarchy's conceptual power and ability to clarify thinking could provide the step change needed to integrate the multiple elements of conservation goals and interventions in order to achieve successful biodiversity outcomes.

16.
Syst Biol ; 66(3): 453-462, 2017 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-27616323

RESUMEN

Species distributions are typically represented by records of their observed occurrence at a given spatial and temporal scale. Such records are inevitably incomplete and contingent on the spatial-temporal circumstances under which the observations were made. Moreover, organisms may respond differently to similar environmental conditions at different places or moments, so their distribution is, in principle, not completely predictable. We argue that this uncertainty exists, and warrants considering species distributions as analogous to coherent quantum objects, whose distributions are better described by a wavefunction rather than by a set of locations. We use this to extend the existing concept of "dark diversity", which incorporates into biodiversity metrics those species that could, but which have not yet been observed to, inhabit a region-thereby developing the idea of "potential biodiversity". We show how conceptualizing species' distributions in this way could help overcome important weaknesses in current biodiversity metrics, both in theory and by using a worked case study of mammal distributions in Spain over the last decade. We propose that considerable theoretical advances could eventually be gained through interdisciplinary collaboration between biogeographers and quantum physicists. [Biogeography; favorability; physics; predictability; probability; species occurrence; uncertainty; wavefunction.


Asunto(s)
Distribución Animal , Biodiversidad , Animales , Mamíferos/clasificación , Mamíferos/fisiología , Filogenia , Teoría Cuántica , España
17.
Ecol Evol ; 4(1): 79-90, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24455163

RESUMEN

Habitat degradation through anthropogenic development is a key driver of biodiversity loss. One way to compensate losses is "biodiversity offsetting" (wherein biodiversity impacted is "replaced" through restoration elsewhere). A challenge in implementing offsets, which has received scant attention in the literature, is the accurate determination of residual biodiversity losses. We explore this challenge for offsetting gas extraction in the Ustyurt Plateau, Uzbekistan. Our goal was to determine the landscape extent of habitat impacts, particularly how the footprint of "linear" infrastructure (i.e. roads, pipelines), often disregarded in compensation calculations, compares with "hub" infrastructure (i.e. extraction facilities). We measured vegetation cover and plant species richness using the line-intercept method, along transects running from infrastructure/control sites outward for 500 m, accounting for wind direction to identify dust deposition impacts. Findings from 24 transects were extrapolated to the broader plateau by mapping total landscape infrastructure network using GPS data and satellite imagery. Vegetation cover and species richness were significantly lower at development sites than controls. These differences disappeared within 25 m of the edge of the area physically occupied by infrastructure. The current habitat footprint of gas infrastructure is 220 ± 19 km(2) across the Ustyurt (total ∼ 100,000 km(2)), 37 ± 6% of which is linear infrastructure. Vegetation impacts diminish rapidly with increasing distance from infrastructure, and localized dust deposition does not conspicuously extend the disturbance footprint. Habitat losses from gas extraction infrastructure cover 0.2% of the study area, but this reflects directly eliminated vegetation only. Impacts upon fauna pose a more difficult determination, as these require accounting for behavioral and demographic responses to disturbance by elusive mammals, including threatened species. This study demonstrates that impacts of linear infrastructure in regions such as the Ustyurt should be accounted for not just with respect to development sites but also associated transportation and delivery routes.

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