The Nature Conservancy (TNC) is a global environmental organization, headquartered in Arlington, Virginia, United States. As of 2021[update] it works via affiliates or branches in 79 countries and territories, as well as across every state in the US.Founded in 1951, The Nature Conservancy has over one million members globally as of 2021[update], and has protected more than 119,000,000 acres (48,000,000 ha) of land and thousands of miles of rivers worldwide.[when?][where?] As of 2014[update], it is the largest environmental non-profit organization by assets and revenue in the Americas.
Water management often requires accounting for reductions in streamflow caused by groundwater pumping (‘streamflow depletion’). Since streamflow depletion cannot be quantified from observational data, it is typically modeled. Analytical depletion functions (ADFs) are a low-cost, low-complexity approach for estimating streamflow depletion with utility for decision support, but ADFs adopt several simplifying assumptions, including an infinite supply of water within the stream. Here, we develop an approach to incorporate stream drying into ADFs to improve their estimation of streamflow and streamflow depletion. Using Scott Valley (California) as an example, we compare ADF results to observed streamflow data and the Scott Valley Integrated Hydrologic Model (SVIHM), a process-based numerical model. ADFs incorporating stream drying have strong agreement with observed streamflow and SVIHM results. Critically, ADFs with drying can simulate a temporal shift in streamflow depletion that occurs when summer stream drying causes stream network disconnections and a substantial fraction of streamflow depletion is lagged until the stream network rewets in the fall/winter. Estimates of what streamflow would have been without groundwater pumping are required to incorporate stream drying into ADFs, and we evaluate the ability of a statewide statistical model of unimpaired monthly streamflow (the California Natural Flows Database [CNFD]) to meet this need. ADFs using CNFD data simulate appropriate temporal dynamics but overestimate streamflow. This suggests that regional unimpaired flow estimates combined with local bias-correction could provide a mechanism to apply ADFs in watersheds without local numerical models.
The Green Heart Project is a community-based trial to evaluate the effects of increasing greenery on urban environment and community health. The study was initiated in 2018 in a low-to-middle-income mixed-race residential area of nearly 28,000 residents in Louisville, KY. The 4 square mile area was surveyed for land use, population characteristics, and greenness, and assigned to 8 paired clusters of demographically- and environmentally matched "target" (T) and adjacent "control" (C), clusters. Ambient levels of ultrafine particles, ozone, oxides of nitrogen, and environmental noise were measured in each cluster. Individual-level data were acquired during in-person exams of 735 participants in Wave 1 (2018-2019) and 545 participants in Wave 2 (2021) to evaluate sociodemographic and psychosocial factors. Blood, urine, nail, and hair samples were collected to evaluate standard cardiovascular risk factors, inflammation, stress, and pollutant exposure. Cardiovascular function was assessed by measuring arterial stiffness and flow-mediated dilation. After completion of Wave 2, more than 8,000 mature, mostly evergreen, trees and shrubs were planted in the T clusters in 2022. Post planting environmental and individual-level data were collected during Wave 3 (2022) from 561 participants. We plan to continue following changes in area characteristics and participant health to evaluate the long-term impact of increasing urban greenery.
The new Kunming-Montreal Post-2020 Global Biodiversity Framework (GBF) calls for transformative change to integrate biodiversity and conservation goals into decision-making across public and private sectors. As a result, biodiversity accounting approaches, which reduce the multifaceted complexity of nature to quantitative metrics for practical applications, are proliferating rapidly. These approaches will be essential for implementing growing practices like nature-based solutions, corporate biodiversity stewardship, no net loss policies, and sustainable infrastructure development. In this perspectives article, we identify ten considerations for biodiversity accounting to ground ongoing discourse in sound ecological science and to better integrate biodiversity into societal decision-making. These considerations pertain to three processes within biodiversity accounting: (1) selecting biodiversity targets, facets, indicators, and metrics, (2) tool and framework design, and (3) implementation. For each consideration, we highlight desirable attributes or practices, which we call “guideposts”, and cautionary notes demarcating problems to be avoided, or “guardrails”. These help to delineate the safe design space for creators and users of biodiversity accounting systems to avoid unintended consequences and reduce risks of failing to achieve conservation objectives via misuse or ineffective approaches. Major considerations include the need for careful disclosure of effort and statistical uncertainty, interoperability and flexibility of frameworks, careful justification and explanation of selected facets, metrics, and indicators, and attention to local social and ecological context. Consideration of these guideposts and guardrails could help avoid unintended consequences like accelerated biodiversity loss and exacerbated environmental injustice while providing a practical basis for achieving the sustainable futures envisioned in the GBF.
In historically frequent fire forests, wildfires are burning larger areas and driving forest loss across western North America, yet they also produce extensive low- to moderate-severity effects that can be leveraged to harden landscapes against future high-severity fire. Here, we operationalize prior conceptual calls by presenting a framework that identifies opportunities to leverage recent wildfire footprints via three management pathways to increasing resistance to high-severity fire: create (use burned edges as containment lines to treat adjacent unburned forest), enhance (apply mechanical treatment and prescribed fire or wildfire managed for resource objectives to areas with one prior beneficial disturbance), and maintain (sustain high-resistance stands with recurring fire). We quantify the extent of these opportunities across California’s Sierra Nevada yellow pine-mixed conifer forests at the Potential Operational Delineations (PODs) scale and outline policy options to act within limited post-fire windows. This work can support increasing resistance to high-severity fire across the landscape, highlighting how leveraging wildfire has the potential to save time and money, lower operational risk under suitable conditions, and promote pyrodiversity and biodiversity.
