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Climate change and other anthropogenic stressors have led to long-term changes in the thermal structure, including surface temperatures, deepwater temperatures, and vertical thermal gradients, in many lakes around the world. Though many studies highlight warming of surface water temperatures in lakes worldwide, less is known about long-term trends in full vertical thermal structure and deepwater temperatures, which have been changing less consistently in both direction and magnitude. Here, we present a globally-expansive data set of summertime in-situ vertical temperature profiles from 153 lakes, with one time series beginning as early as 1894. We also compiled lake geographic, morphometric, and water quality variables that can influence vertical thermal structure through a variety of potential mechanisms in these lakes. These long-term time series of vertical temperature profiles and corresponding lake characteristics serve as valuable data to help understand changes and drivers of lake thermal structure in a time of rapid global and ecological change.

Applying science to conservation requires deliberate planning and action infrequently taught in academic settings. To illustrate impactful analysis and science communication, we describe scientific activities targeting the needs of land trusts, NGOs, landowners, and government agencies working to conserve the Florida Wildlife Corridor ("Corridor"). This 7.2 million hectare area is prioritized for habitat connectivity conservation in the US state of Florida. Our activities are built on decades of science guiding Florida land conservation. We quantified threats (e.g., average of over 14,000 ha of development/year from 2001 to 2019) and socio‐ecological benefits of Corridor conservation, prioritized yet‐to‐be‐conserved Corridor areas, produced and shared a new statewide connectivity model, and convened groups to identify campaign science needs. The new connectivity model—the Florida Circuit Model—supported the geography of the Corridor, as designated, and facilitates local (10 km radius, or less) conservation planning. Our efforts have contributed to allocation of over $2 billion for land conservation and the permanent protection of over 82,000 ha within the Corridor by state agencies from June 2021 to March 2024. Targeting science to outreach and policy, planning, and management decisions can motivate public, media, researcher, and government support for land conservation, improve conservation interventions, and attract research funding. [ABSTRACT FROM AUTHOR]

Questions: Grasslands provide important provisioning services worldwide and their management has consequences for these services. Management intensification is a widespread land‐use change and has accelerated across North America to meet rising demands on productivity, yet its impact on the relationship between plant diversity and productivity is still unclear. Here, we investigated the relationship between plant diversity and grassland productivity across nine ecoclimatic domains of the continental United States. We also tested the effect of management intensification on diversity and productivity in four case studies. Methods: We acquired remotely sensed gross primary productivity data (GPP, 1986–2018) and plant diversity data measured at different spatial scales (1, 10, 100, 400 m2), as well as climate variables including the Palmer drought index from two ecological networks. We used general linear mixed models to relate GPP to plant diversity across sites. For the case study analysis, we used linear mixed models to relate plant diversity to management intensity, and tested if the management intensity influenced the relationship between GPP (mean and temporal variation) and drought. Results: Across all sites, we observed positive relationships among species richness, productivity, and the temporal stability of mean annual biomass production. These relationships were not affected by the scale at which species richness was observed. In three out of the four case studies, we observed that management effects on species richness were only significant at broader scales (i.e., ≥10 m2) with no clear effect found at the commonly used 1‐m2 quadrat scale. In one case study, species‐poor, intensively managed pastures presented the highest productivity but were more sensitive to dry conditions than less intensified pastures. However, in other case studies, we did not observe significant effects of management intensity on the magnitude or stability of productivity. Conclusions: Generalization across studies may be difficult and require the development of intensification indices general enough to be applied across diverse management strategies in grazilands. Understanding how management intensification affects grassland productivity will inform the development of sustainable intensification strategies. [ABSTRACT FROM AUTHOR]

Biodiversity impacts are rarely included in systems analyses of livestock production. We piloted two approaches toward quantifying biodiversity impacts, pressure‐state‐response (PSR) and potential species loss (PSL), at a cow–calf operation in Florida for which extensive environmental data were available. Using these approaches, we compared livestock production on two vegetation types, semi‐native pasture (SNP) and improved pasture (IMP), and we found fewer deleterious effects on biodiversity associated with SNP (characterized by low stocking rates and no fertilizer) than with IMP, as evidenced by a lower PSL and greater biotic integrity under PSR. Both approaches agreed in the direction of the outcome, but we argue that, when possible, they should be applied complementarily to inform both absolute and per‐unit product biodiversity impacts of livestock production. This research demonstrates how to incorporate biodiversity into life‐cycle perspectives of livestock sustainability assessments when data availability varies, supporting the expansion of multi‐metric, holistic evaluations that are absent from most livestock system analyses. [ABSTRACT FROM AUTHOR]

To purchase or authenticate to the full-text of this article, please visit this link: http://dx.doi.org/10.1111/j.1523-1739.2006.00536.x Byline: WILL R. TURNER (*s.), DAVID S. WILCOVE (*[dagger]), HILARY M. SWAIN ([double dagger]) Keywords: endangered species; IUCN Red List; Lake Wales Ridge (Florida); protection index; sandhill; scrub Abstract: Abstract: Measuring the effectiveness of reserve networks is essential to ensure that conservation objectives such as species persistence are being met. We devised a new approach for measuring the effectiveness of land conservation in protecting rare and threatened species and applied it to an ecosystem of global significance. We compiled detailed global distributional data for 36 rare and threatened plants and animals found in the Lake Wales Ridge ecosystem in central Florida (U.S.A.). For each species, we developed a set of protection indices based in part on criteria used to categorize species for the World Conservation Union's Red List. We calculated protection indexes under three different conservation scenarios: a past scenario, which assumed recent, major land-acquisition efforts never occurred; a current scenario, which assumed no additional areas are saved beyond what is currently protected; and a targeted scenario, which assumed all of the remaining areas targeted for protection are eventually acquired. This approach enabled us to quantify the progress, in terms of reduced risk of extinction, that conservationists have made in protecting target species. It also revealed the limited success these land-acquisition efforts have had in reducing those extinction risks associated with loss of habitat or small geographic ranges. Many species of the Lake Wales Ridge will remain at high risk of extinction even if planned land-acquisition efforts are completely successful. By calculating protection indexes with and without each site for all imperiled species, we also quantified the contribution of each protected area to the conservation of each species, enabling local conservation decisions to be made in the context of a larger (global) perspective. The protection index approach can be adapted readily to other ecosystems with multiple rare and threatened species. Abstract (Spanish): Evaluacion de la Efectividad de los Programas de Adquisicion de Reservas en la Proteccion de Especies Raras y Amenazadas Resumen: La cuantificacion de la efectividad de las redes de reservas es esencial para asegurar que objetivos, como la persistencia de especies, se cumplan. Disenamos un nuevo metodo para medir la efectividad de la conservacion de tierras en la proteccion de especies raras y amenazadas y lo aplicamos a un ecosistema de importancia global. Compilamos datos detallados de la distribucion global de 36 especies raras y amenazadas de plantas y animales que se encuentran en el ecosistema de la Lake Wales Ridge en el centro de Florida (E.U.A.). Para cada especie desarrollamos un conjunto de indices de proteccion basado parcialmente en criterios utilizados para clasificar especies para la Lista Roja de la Union Mundial para la Naturaleza. Calculamos los indices de proteccion bajo tres escenarios de conservacion distintos: un escenario pasado, que asumia que los esfuerzos recientes de adquisicion de tierras nunca ocurrieron; un escenario actual, que asumia que no se protegen areas adicionales a las ya conservadas; y un escenario deseado, que asumia que todas las areas consideradas para ser protegidas son adquiridas eventualmente. Este metodo nos permitio cuantificar el progreso, en terminos de la reduccion del riesgo de extincion, en la proteccion de las especies obtenido por conservacionistas. Tambien revelo el exito limitado de los esfuerzos de adquisicion de tierras en la disminucion de los riesgos de extincion asociados con la perdida de habitat o con rangos geograficos pequenos. Se pronostico que muchas especies de la Lake Wales Ridge permaneceran en alto riesgo aun si los esfuerzos de adquisicion de tierra planificados son completamente exitosos. Al calcular los indices de proteccion con y sin cada sitio para todas las especies en peligro, tambien cuantificamos la contribucion de cada area protegida a la conservacion de cada especie, lo que permite que las decisiones de conservacion se tomen en el contexto de una perspectiva mayor (global). El metodo del indice de proteccion se puede adaptar facilmente a otros ecosistemas con multiples especies raras y amenazadas. Author Affiliation: (*)Princeton Environmental Institute and Woodrow Wilson School of Public and International Affairs, Princeton University, Princeton, NJ 08544, U.S.A. ([dagger])Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544, U.S.A. ([double dagger])Archbold Biological Station, PO Box 2057, Lake Placid, FL 33862, U.S.A. Article History: Paper submitted August 16, 2005; revised manuscript accepted March 1, 2006. Article note: (s.) Current address: Center for Applied Biodiversity Science, 1919 M St. NW Suite 600, Washington, D.C. 20036, U.S.A., email w.turner@conservation.org

Phytoplankton assembly dynamics in lakes are highly sensitive to variability in climate drivers and resulting physicochemical changes in lake water columns. As climate change increases the frequency of major precipitation events and droughts, many lakes experience increased inputs of colored dissolved organic carbon (CDOC) and nutrients. How these CDOC‐related changes in resources, transparency, and thermal stability affect phytoplankton assemblages, succession, and resilience is understudied, particularly in subtropical lakes. Here, we used time series, multivariate, and trait‐based functional redundancy analyses to elucidate the roles of phytoplankton in ecosystem resilience and determine potential drivers of assemblage shifts in a subtropical monomictic lake with fluctuating CDOC inputs (Lake Annie, Highlands County, Florida, USA). We found that phytoplankton assemblages and successional patterns differed between two dark‐water states (late 2005–mid‐2007, late 2012–2019) bracketing a clear‐water state (mid‐2007–late 2012), caused by shifting CDOC and nutrient concentrations associated with oscillating groundwater levels. Diatoms (Bacillariophyta), which were dominant during the two dark‐water states, nearly disappeared and were replaced by synurophytes during the clear‐water state. Assemblages had greater interannual consistency in the dark‐water states, while mean functional redundancy decreased in the clear‐water state. Seasonal phytoplankton successional changes were also more pronounced and synchronized with seasonal hydrologic shifts in the dark‐water states. Multiyear assemblage shifts occurred more quickly in clear‐to‐dark than dark‐to‐clear state transitions, suggesting phytoplankton in dark‐water states may be more resistant to state transitions or even contribute to dark‐water state resilience via feedback loops. [ABSTRACT FROM AUTHOR]

A New Century of Biology. John W. Kress and Gary W. Barrett, eds. Smithsonian Institution Press, in association with the American Institute of Biological Sciences, Washington, DC, 2001. 208 pp., [...]