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Lawrence E. Stevens
Springs Stewardship Institute, Museum of Northern Arizona 3101 N. Ft. Valley Rd. Flagstaff AZ 86001 U.S.A.

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Diversity
Published: 02 September 2020 in Conservation Biology
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ACS Style

Marco Cantonati; Roderick J. Fensham; Lawrence E. Stevens; Reinhard Gerecke; Douglas S. Glazier; Nico Goldscheider; Robert L. Knight; John S. Richardson; Abraham E. Springer; Klement Tockner. Urgent plea for global protection of springs. Conservation Biology 2020, 35, 378 -382.

AMA Style

Marco Cantonati, Roderick J. Fensham, Lawrence E. Stevens, Reinhard Gerecke, Douglas S. Glazier, Nico Goldscheider, Robert L. Knight, John S. Richardson, Abraham E. Springer, Klement Tockner. Urgent plea for global protection of springs. Conservation Biology. 2020; 35 (1):378-382.

Chicago/Turabian Style

Marco Cantonati; Roderick J. Fensham; Lawrence E. Stevens; Reinhard Gerecke; Douglas S. Glazier; Nico Goldscheider; Robert L. Knight; John S. Richardson; Abraham E. Springer; Klement Tockner. 2020. "Urgent plea for global protection of springs." Conservation Biology 35, no. 1: 378-382.

Articles
Published: 16 August 2020 in Ecological Applications
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Springs ecosystems are globally abundant, geomorphologically diverse, and bio‐culturally productive, but are highly imperiled by anthropogenic activities. More than a century of scientific discussion about the wide array of ecohydrological factors influencing springs has been informative, but has yielded little agreement on their classification. This lack of agreement has contributed to the global neglect and degradation of springs ecosystems by the public, scientific, and management communities. Here we review the historical literature on springs classification variables, concluding that site‐specific source geomorphology remains the most diagnostic approach. We present a conceptual springs ecosystem model that clarifies the central role of geomorphology in springs ecosystem development, function, and typology. We present an illustrated dichotomous key to terrestrial (non‐marine) springs ecosystem types and subtypes, and describe those types. We identify representative reference sites, although data limitations presently preclude selection of continentally or globally representative reference springs of each type. We tested the classification key using data from 244 randomly selected springs of 13 types that were inventoried in western North America. The dichotomous key correctly identified springs type in 87.5% of the cases, with discrepancies primarily due to differentiation of primary versus secondary typology, and insufficient inventory team training. Using that information, we identified sources of confusion and clarified the key. Among the types that required more detailed explanation were hypocrenes, springs, in which groundwater is expressed through phreatophytic vegetation. Overall, springs biodiversity and ecosystem complexity are due, in part, to the co‐occurrence of multiple intra‐springs microhabitats. We describe microhabitats that are commonly associated with different springs types, reporting at least 13 microhabitats, each which can support discrete biotic assemblages. Interdisciplinary agreement on basic classification is needed to enhance scientific understanding and stewardship of springs ecosystems, the loss and degradation of which constitute a global conservation crisis.

ACS Style

Lawrence E. Stevens; Edward R. Schenk; Abraham E. Springer. Springs ecosystem classification. Ecological Applications 2020, 31, 1 .

AMA Style

Lawrence E. Stevens, Edward R. Schenk, Abraham E. Springer. Springs ecosystem classification. Ecological Applications. 2020; 31 (1):1.

Chicago/Turabian Style

Lawrence E. Stevens; Edward R. Schenk; Abraham E. Springer. 2020. "Springs ecosystem classification." Ecological Applications 31, no. 1: 1.

Journal article
Published: 24 May 2020 in Water
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The Colorado River basin (CRB), the primary water source for southwestern North America, is divided into the 283,384 km2, water-exporting Upper CRB (UCRB) in the Colorado Plateau geologic province, and the 344,440 km2, water-receiving Lower CRB (LCRB) in the Basin and Range geologic province. Long-regarded as a snowmelt-fed river system, approximately half of the river’s baseflow is derived from groundwater, much of it through springs. CRB springs are important for biota, culture, and the economy, but are highly threatened by a wide array of anthropogenic factors. We used existing literature, available databases, and field data to synthesize information on the distribution, ecohydrology, biodiversity, status, and potential socio-economic impacts of 20,872 reported CRB springs in relation to permanent stream distribution, human population growth, and climate change. CRB springs are patchily distributed, with highest density in montane and cliff-dominated landscapes. Mapping data quality is highly variable and many springs remain undocumented. Most CRB springs-influenced habitats are small, with a highly variable mean area of 2200 m2, generating an estimated total springs habitat area of 45.4 km2 (0.007% of the total CRB land area). Median discharge also is generally low and variable (0.10 L/s, N = 1687, 95% CI = 0.04 L/s), but ranges up to 1800 L/s. Water pH and conductivity is negatively related to elevation, with a stronger negative relationship in the UCRB compared to the LCRB. Natural springs water temperature and geochemistry throughout the CRB varies greatly among springs, but relatively little within springs, and depends on aquifer hydrogeology, elevation, and residence time. As the only state nearly entirely included within the CRB, Arizona is about equally divided between the two geologic provinces. Arizona springs produce approximately 0.6 km3/year of water. Data on >330 CRB springs-dependent taxa (SDT) revealed at least 62 plant species; 216 aquatic and riparian Mollusca, Hemiptera, Coleoptera, and other invertebrate taxa; several herpetofanual species; and two-thirds of 35 CRB fish taxa. Springs vegetation structure, composition, and diversity vary strongly by springs type, and plant species density within springs is high in comparison with upland habitats. Plant species richness and density is negatively related to elevation below 2500 m. Human population in and adjacent to the CRB are growing rapidly, and ecological impairment of springs exceeds 70% in many landscapes, particularly in urbanized and rangeland areas. Anthropogenic stressors are primarily related to groundwater depletion and pollution, livestock management, flow abstraction, non-native species introduction, and recreation. Ensuring the ecological integrity and sustainability of CRB groundwater supplies and springs will require more thorough basic inventory, assessment, research, information management, and local ecosystem rehabilitation, as well as improved groundwater and springs conservation policy.

ACS Style

Lawrence E. Stevens; Jeffrey Jenness; Jeri D. Ledbetter. Springs and Springs-Dependent Taxa of the Colorado River Basin, Southwestern North America: Geography, Ecology and Human Impacts. Water 2020, 12, 1501 .

AMA Style

Lawrence E. Stevens, Jeffrey Jenness, Jeri D. Ledbetter. Springs and Springs-Dependent Taxa of the Colorado River Basin, Southwestern North America: Geography, Ecology and Human Impacts. Water. 2020; 12 (5):1501.

Chicago/Turabian Style

Lawrence E. Stevens; Jeffrey Jenness; Jeri D. Ledbetter. 2020. "Springs and Springs-Dependent Taxa of the Colorado River Basin, Southwestern North America: Geography, Ecology and Human Impacts." Water 12, no. 5: 1501.

Encyclopedia
Published: 29 February 2020 in Encyclopedia of the World's Biomes
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Springs ecosystems occur where groundwater reaches the Earth's surface, and are physically and biologically significant, complex, and highly socio-ecologically interactive ecosystems, particularly in arid regions. However, springs are threatened by intensifying human appropriation, contamination of groundwater, and surface habitat destruction. I review the literature and conceptual underpinnings of ecosystem ecology, springs distribution, typology, eco-evolutionary, and socio-cultural characteristics and processes in arid versus mesic/humid landscapes, and identify conceptual and data gaps. I estimate that the world's at least 2.3 million terrestrial springs produce at least 10.7 km3 of water/year. Most ecohydrogeological characteristics and processes discussed apply to all terrestrial springs across latitude and elevation; however, aridland springs differentially or more often have: (1) steeper environmental moisture and nutrient gradients between adjacent uplands, (2) distinctively different biotic assemblages; (3) higher occurrence of endemism and rare species in evolutionarily significant paleorefugia; (4) interrupted, losing-stream springbrooks, disconnectivity that retards non-native species colonization; (5) lower levels of flow and increased ephemeral flow; (6) reduced resiliency and more dynamism in vegetation development following disturbance; (7) greater susceptibility to anthropogenic impacts that leads to (8) loss of springs habitat and increased probability and incidence of extinction of springs-dependent species. These differences and greater conservation urgency elevate the need for improved stewardship of aridland springs. The study of aridland springs reveals much about the ecohydrology, distribution, ecological development and function, biogeography, ecological roles, and importance to humanity of springs everywhere, and the need and opportunities for enhanced stewardship of this highly endangered biome.

ACS Style

Lawrence E. Stevens. The Springs Biome, with an Emphasis on Arid Regions. Encyclopedia of the World's Biomes 2020, 354 -370.

AMA Style

Lawrence E. Stevens. The Springs Biome, with an Emphasis on Arid Regions. Encyclopedia of the World's Biomes. 2020; ():354-370.

Chicago/Turabian Style

Lawrence E. Stevens. 2020. "The Springs Biome, with an Emphasis on Arid Regions." Encyclopedia of the World's Biomes , no. : 354-370.

Review
Published: 16 January 2020 in Water
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In this overview (introductory article to a special issue including 14 papers), we consider all main types of natural and artificial inland freshwater habitas (fwh). For each type, we identify the main biodiversity patterns and ecological features, human impacts on the system and environmental issues, and discuss ways to use this information to improve stewardship. Examples of selected key biodiversity/ecological features (habitat type): narrow endemics, sensitive (groundwater and GDEs); crenobionts, LIHRes (springs); unidirectional flow, nutrient spiraling (streams); naturally turbid, floodplains, large-bodied species (large rivers); depth-variation in benthic communities (lakes); endemism and diversity (ancient lakes); threatened, sensitive species (oxbow lakes, SWE); diverse, reduced littoral (reservoirs); cold-adapted species (Boreal and Arctic fwh); endemism, depauperate (Antarctic fwh); flood pulse, intermittent wetlands, biggest river basins (tropical fwh); variable hydrologic regime—periods of drying, flash floods (arid-climate fwh). Selected impacts: eutrophication and other pollution, hydrologic modifications, overexploitation, habitat destruction, invasive species, salinization. Climate change is a threat multiplier, and it is important to quantify resistance, resilience, and recovery to assess the strategic role of the different types of freshwater ecosystems and their value for biodiversity conservation. Effective conservation solutions are dependent on an understanding of connectivity between different freshwater ecosystems (including related terrestrial, coastal and marine systems).

ACS Style

Marco Cantonati; Sandra Poikane; Catherine M. Pringle; Lawrence E. Stevens; Eren Turak; Jani Heino; John S. Richardson; Rossano Bolpagni; Alex Borrini; Núria Cid; Martina Čtvrtlíková; Diana M. P. Galassi; Michal Hájek; Ian Hawes; Zlatko Levkov; Luigi Naselli-Flores; Abdullah A. Saber; Mattia Di Cicco; Barbara Fiasca; Paul B. Hamilton; Jan Kubečka; Stefano Segadelli; Petr Znachor. Characteristics, Main Impacts, and Stewardship of Natural and Artificial Freshwater Environments: Consequences for Biodiversity Conservation. Water 2020, 12, 260 .

AMA Style

Marco Cantonati, Sandra Poikane, Catherine M. Pringle, Lawrence E. Stevens, Eren Turak, Jani Heino, John S. Richardson, Rossano Bolpagni, Alex Borrini, Núria Cid, Martina Čtvrtlíková, Diana M. P. Galassi, Michal Hájek, Ian Hawes, Zlatko Levkov, Luigi Naselli-Flores, Abdullah A. Saber, Mattia Di Cicco, Barbara Fiasca, Paul B. Hamilton, Jan Kubečka, Stefano Segadelli, Petr Znachor. Characteristics, Main Impacts, and Stewardship of Natural and Artificial Freshwater Environments: Consequences for Biodiversity Conservation. Water. 2020; 12 (1):260.

Chicago/Turabian Style

Marco Cantonati; Sandra Poikane; Catherine M. Pringle; Lawrence E. Stevens; Eren Turak; Jani Heino; John S. Richardson; Rossano Bolpagni; Alex Borrini; Núria Cid; Martina Čtvrtlíková; Diana M. P. Galassi; Michal Hájek; Ian Hawes; Zlatko Levkov; Luigi Naselli-Flores; Abdullah A. Saber; Mattia Di Cicco; Barbara Fiasca; Paul B. Hamilton; Jan Kubečka; Stefano Segadelli; Petr Znachor. 2020. "Characteristics, Main Impacts, and Stewardship of Natural and Artificial Freshwater Environments: Consequences for Biodiversity Conservation." Water 12, no. 1: 260.

Journal article
Published: 02 January 2019 in Forest Ecology and Management
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Tree rings have been widely used to reconstruct environmental history, especially water availability, because historical records of streamflow are often limited. In the semiarid southwestern USA, springs provide critical water resources and support biodiversity hotspots, but spring flows are poorly documented and spring effects on tree-ring growth are not well studied. Our project was designed to measure the effect of spring adjacency on ponderosa pine tree growth and drought response. We sampled trees adjacent to springs (“near”) and farther away (“away”) that were similar in latitude, slope, soil characteristics, height and stem diameter, so we inferred that differences in ring width were due to the springś influences. We gathered cores from a total of 50 ponderosa pine trees at ten different springs around Flagstaff, Arizona. We crossdated and measured the tree rings and developed chronologies of near and away trees. We compared absolute growth of trees in each category using basal area increment (BAI; mm2/year), which ranged from 806 to 2511 mm2 tree−1 year−1 near springs and between 503 and 2125 mm2 tree−1 year−1 away from springs. Near trees had consistently higher BAI growth over the past 66 years, the common period of analysis, although the difference was not statistically significant. Mean tree-ring sensitivity from the chronology near springs was 0.323, while the chronology away from springs was significantly higher, 0.366. Drought sensitivity index was significantly higher for away trees, indicating that years of severe drought had a greater negative impact for away than for near trees. Drought recovery index, however, showed inconsistent results. The findings indicate that ponderosa pine growth is responsive to spring settings, even in severe drought. Given that small springs are abundant in semiarid regions, they may provide valuable ecological buffers for warming climate. Further investigation to quantify springs perenniality and variability is needed.

ACS Style

Louise Fuchs; Lawrence E. Stevens; Peter Z. Fulé. Dendrochronological assessment of springs effects on ponderosa pine growth, Arizona, USA. Forest Ecology and Management 2019, 435, 89 -96.

AMA Style

Louise Fuchs, Lawrence E. Stevens, Peter Z. Fulé. Dendrochronological assessment of springs effects on ponderosa pine growth, Arizona, USA. Forest Ecology and Management. 2019; 435 ():89-96.

Chicago/Turabian Style

Louise Fuchs; Lawrence E. Stevens; Peter Z. Fulé. 2019. "Dendrochronological assessment of springs effects on ponderosa pine growth, Arizona, USA." Forest Ecology and Management 435, no. : 89-96.