Pub Date : 2020-10-01DOI: 10.1637/0003-0031-184.2.222
Landon R. Jones, P. Zollner, R. Swihart, Emily Godollei, Cassie M. Hudson, S. Johnson
Abstract. Bobcat (Lynx rufus) populations have increased in the midwestern U.S. since the 1980s after substantial declines and local extirpations into the mid-1900s. We monitored 38 radio-collared bobcats (25 males, 13 females) from 1998 to 2006 in a recovering population in south-central Indiana to investigate survival and mortality causes. Annual survival was high (Ŝ = 0.80, 95% CI = 0.71–0.89), comparable to results from other studies of bobcats in unexploited populations and higher than in harvested populations. Of 17 known deaths, vehicle collisions were the largest source of mortality (n = 9; 53%), followed by illegal shootings (n = 3; 18%). Higher values of habitat heterogeneity within home ranges were associated with lower risk of mortality. Estimates of survival and mortality sources in recovering populations provide an important context to compare management strategies to improve bobcat conservation.
{"title":"Survival and Mortality Sources in a Recovering Population of Bobcats (Lynx rufus) in South-central Indiana","authors":"Landon R. Jones, P. Zollner, R. Swihart, Emily Godollei, Cassie M. Hudson, S. Johnson","doi":"10.1637/0003-0031-184.2.222","DOIUrl":"https://doi.org/10.1637/0003-0031-184.2.222","url":null,"abstract":"Abstract. Bobcat (Lynx rufus) populations have increased in the midwestern U.S. since the 1980s after substantial declines and local extirpations into the mid-1900s. We monitored 38 radio-collared bobcats (25 males, 13 females) from 1998 to 2006 in a recovering population in south-central Indiana to investigate survival and mortality causes. Annual survival was high (Ŝ = 0.80, 95% CI = 0.71–0.89), comparable to results from other studies of bobcats in unexploited populations and higher than in harvested populations. Of 17 known deaths, vehicle collisions were the largest source of mortality (n = 9; 53%), followed by illegal shootings (n = 3; 18%). Higher values of habitat heterogeneity within home ranges were associated with lower risk of mortality. Estimates of survival and mortality sources in recovering populations provide an important context to compare management strategies to improve bobcat conservation.","PeriodicalId":50802,"journal":{"name":"American Midland Naturalist","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43399853","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-10-01DOI: 10.1637/0003-0031-184.2.233
Caleb C. Artz, M. Pyron, L. Bowley
Abstract. We tested macroinvertebrate assemblages collected from 1979–2015 for temporal variation in structure and for impacts of the Clean Water Act of 1974. Collections were at ten sites on the mainstem of the West Fork White River. We used family-level taxonomy for macroinvertebrates that resulted in 77 families and 92,477 individuals. Macroinvertebrate families were further classified by trophic and tolerance traits and tested for temporal variation. We defined river reaches as upstream, urban, and downstream of Muncie, Indiana for analyses. Taxonomic richness increased over the study. A nonmetric multidimensional scaling (NMDS) analysis identified high temporal variation as assemblage structure differed among decades. Spatial analyses using NMDS indicated significant differences by river location upstream, urban, and downstream. NMDS and Analysis of Similarities (ANOSIM) by trophic relationship and tolerance values did not result in significant temporal or spatial patterns. Our results show the macroinvertebrate assemblages of the West Fork White River improved, likely due to implementation of the Clean Water Act.
{"title":"Long-term Macroinvertebrate Assemblages of the West Fork White River, Indiana Improve Following the Clean Water Act","authors":"Caleb C. Artz, M. Pyron, L. Bowley","doi":"10.1637/0003-0031-184.2.233","DOIUrl":"https://doi.org/10.1637/0003-0031-184.2.233","url":null,"abstract":"Abstract. We tested macroinvertebrate assemblages collected from 1979–2015 for temporal variation in structure and for impacts of the Clean Water Act of 1974. Collections were at ten sites on the mainstem of the West Fork White River. We used family-level taxonomy for macroinvertebrates that resulted in 77 families and 92,477 individuals. Macroinvertebrate families were further classified by trophic and tolerance traits and tested for temporal variation. We defined river reaches as upstream, urban, and downstream of Muncie, Indiana for analyses. Taxonomic richness increased over the study. A nonmetric multidimensional scaling (NMDS) analysis identified high temporal variation as assemblage structure differed among decades. Spatial analyses using NMDS indicated significant differences by river location upstream, urban, and downstream. NMDS and Analysis of Similarities (ANOSIM) by trophic relationship and tolerance values did not result in significant temporal or spatial patterns. Our results show the macroinvertebrate assemblages of the West Fork White River improved, likely due to implementation of the Clean Water Act.","PeriodicalId":50802,"journal":{"name":"American Midland Naturalist","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42228494","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-10-01DOI: 10.1637/0003-0031-184.2.268
Jordan M. Pruszenski, D. Hernández
Abstract. Herbivores can have nonconsumptive effects on ecosystems, including the redistribution of nutrients in their waste. In tallgrass prairie bison (Bison bison) historically increased soil nitrogen availability via labile waste deposits. White-tailed deer (Odocoileus virginianus) are now the dominant native large herbivore in prairie and have been shown to consume higher nutrient-content plants than those preferred by bison. Deer are also edge-dwelling species that reuse the trails they make as they move and browse throughout the prairie. Therefore, deer may differ from bison in their spatial patterns of nutrient content and redistribution of fecal matter. We examined the nutrient content and spatial distribution of deer pellets by measuring the number of deer pellet piles along deer trails and transects that were systematically placed at the forest border and in open prairie. We also measured the nitrogen content of deer pellets. White-tailed deer pellets had twofold greater nitrogen concentrations (3.43% N and 40.8% C) compared to values reported for bison fecal matter. Deer pellet piles were more concentrated on deer trails compared to the transects, resulting in fourfold greater N inputs on deer trails compared to areas off of trails. As a result, White-tailed deer have the potential to create patches of increased nutrient availability through their clumped distribution of nutrient rich fecal matter, with potential consequences for prairie plant communities.
{"title":"White-tailed Deer Fecal Matter Distribution and Nutrient Contribution in Tallgrass Prairie","authors":"Jordan M. Pruszenski, D. Hernández","doi":"10.1637/0003-0031-184.2.268","DOIUrl":"https://doi.org/10.1637/0003-0031-184.2.268","url":null,"abstract":"Abstract. Herbivores can have nonconsumptive effects on ecosystems, including the redistribution of nutrients in their waste. In tallgrass prairie bison (Bison bison) historically increased soil nitrogen availability via labile waste deposits. White-tailed deer (Odocoileus virginianus) are now the dominant native large herbivore in prairie and have been shown to consume higher nutrient-content plants than those preferred by bison. Deer are also edge-dwelling species that reuse the trails they make as they move and browse throughout the prairie. Therefore, deer may differ from bison in their spatial patterns of nutrient content and redistribution of fecal matter. We examined the nutrient content and spatial distribution of deer pellets by measuring the number of deer pellet piles along deer trails and transects that were systematically placed at the forest border and in open prairie. We also measured the nitrogen content of deer pellets. White-tailed deer pellets had twofold greater nitrogen concentrations (3.43% N and 40.8% C) compared to values reported for bison fecal matter. Deer pellet piles were more concentrated on deer trails compared to the transects, resulting in fourfold greater N inputs on deer trails compared to areas off of trails. As a result, White-tailed deer have the potential to create patches of increased nutrient availability through their clumped distribution of nutrient rich fecal matter, with potential consequences for prairie plant communities.","PeriodicalId":50802,"journal":{"name":"American Midland Naturalist","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47122046","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-10-01DOI: 10.1637/0003-0031-184.2.149
Priscilla A. Nyamai, Todd A. Aschenbach, Justin L. Heslinga
Abstract. Oak-pine barrens ecosystems provide critical habitat for the federally endangered Karner blue butterfly (Lycaeides melissa samuelis). Wild lupine (Lupinus perennis), an herbaceous perennial in this ecosystem is the only food source for the butterfly's larvae. The range and quality of these ecosystems have declined significantly. Restoration in private lands can be key to expanding these habitats, but often there is limited or no follow-up to assess the recovery of the site following restoration treatments. We conducted a case study in a private property in Newaygo County, Michigan for which prescribed fire had been implemented every 2 y from 2007 through 2011 to promote recruitment of key understory vegetation, but there had been no follow-up recovery assessment. The burn treatment consisted of a section that was not burned, one that was burned twice, and one that was burned three times. We collected data on vegetation groups and site related factors along this fire gradient to examine differences as a function of fire frequency, as well as delineate factors driving patterns of understory plant recruitment. Results show little tree recruitment from seedlings, but high densities of tree saplings recruited via resprouting. Estimated cover of lupine was low across all treatments, whereas Pennsylvania sedge (Carex pensylvanica Lam,) was highest among species in both cover and biomass. Lupine exhibited a negative relationship with Pennsylvania sedge, litter, and sprouted tree saplings, but a positive relationship with moss cover. We make recommendations for additional restoration interventions and highlight the need for continued support of private landowners as they engage in conservation of imperiled species.
{"title":"Restoration on Private Lands: A Case Study Examining Vegetation Recruitment following Restoration Treatments in an Oak-pine Barrens Ecosystem in Western Michigan, U.S.A.","authors":"Priscilla A. Nyamai, Todd A. Aschenbach, Justin L. Heslinga","doi":"10.1637/0003-0031-184.2.149","DOIUrl":"https://doi.org/10.1637/0003-0031-184.2.149","url":null,"abstract":"Abstract. Oak-pine barrens ecosystems provide critical habitat for the federally endangered Karner blue butterfly (Lycaeides melissa samuelis). Wild lupine (Lupinus perennis), an herbaceous perennial in this ecosystem is the only food source for the butterfly's larvae. The range and quality of these ecosystems have declined significantly. Restoration in private lands can be key to expanding these habitats, but often there is limited or no follow-up to assess the recovery of the site following restoration treatments. We conducted a case study in a private property in Newaygo County, Michigan for which prescribed fire had been implemented every 2 y from 2007 through 2011 to promote recruitment of key understory vegetation, but there had been no follow-up recovery assessment. The burn treatment consisted of a section that was not burned, one that was burned twice, and one that was burned three times. We collected data on vegetation groups and site related factors along this fire gradient to examine differences as a function of fire frequency, as well as delineate factors driving patterns of understory plant recruitment. Results show little tree recruitment from seedlings, but high densities of tree saplings recruited via resprouting. Estimated cover of lupine was low across all treatments, whereas Pennsylvania sedge (Carex pensylvanica Lam,) was highest among species in both cover and biomass. Lupine exhibited a negative relationship with Pennsylvania sedge, litter, and sprouted tree saplings, but a positive relationship with moss cover. We make recommendations for additional restoration interventions and highlight the need for continued support of private landowners as they engage in conservation of imperiled species.","PeriodicalId":50802,"journal":{"name":"American Midland Naturalist","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43690194","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-10-01DOI: 10.1637/0003-0031-184.2.205
Mary E. Bennett, Robert A. Gitzen, L. Conner, Mark D Smith, Eric C. Soehren, S. Castleberry
Abstract. Pocket gophers (Geomyidae) require soils amenable to burrowing and vegetation communities that provide adequate foods. We examined the interplay of soil texture and vegetation structure in determining site occupancy of the southeastern pocket gopher (Geomys pinetis), a species of conservation concern throughout its range. Using a case-control sampling design, we compared vegetation structure and soil texture between occupied and unoccupied sites in southeastern Alabama. All occupied sites had soil clay content ≤8.05% at 0–20 cm depth. In logistic regression modeling, clay content had overwhelming support as the most important single habitat variable distinguishing occupied from unoccupied sites. Based on soil results, we focused our examination of vegetation structure on the subset of our sites with <10% clay at 0–20 cm depth. Relative odds of occupancy were highest at intermediate levels of canopy cover; however, canopy cover at occupied sites ranged widely. Compared to unoccupied sites, occupied sites contained less midstory cover and greater ground cover of graminoids and shrubs. Our results demonstrate that although vegetation structure is important in determining site suitability, soil texture may be an overriding constraint limiting potential habitat for this species. Conservation actions for southeastern pocket gophers such as habitat restoration and population translocations should ensure that target sites have suitable low-clay soils.
{"title":"Interactions of Soil and Vegetation Determine Habitat for Southeastern Pocket Gopher (Geomys pinetis)","authors":"Mary E. Bennett, Robert A. Gitzen, L. Conner, Mark D Smith, Eric C. Soehren, S. Castleberry","doi":"10.1637/0003-0031-184.2.205","DOIUrl":"https://doi.org/10.1637/0003-0031-184.2.205","url":null,"abstract":"Abstract. Pocket gophers (Geomyidae) require soils amenable to burrowing and vegetation communities that provide adequate foods. We examined the interplay of soil texture and vegetation structure in determining site occupancy of the southeastern pocket gopher (Geomys pinetis), a species of conservation concern throughout its range. Using a case-control sampling design, we compared vegetation structure and soil texture between occupied and unoccupied sites in southeastern Alabama. All occupied sites had soil clay content ≤8.05% at 0–20 cm depth. In logistic regression modeling, clay content had overwhelming support as the most important single habitat variable distinguishing occupied from unoccupied sites. Based on soil results, we focused our examination of vegetation structure on the subset of our sites with <10% clay at 0–20 cm depth. Relative odds of occupancy were highest at intermediate levels of canopy cover; however, canopy cover at occupied sites ranged widely. Compared to unoccupied sites, occupied sites contained less midstory cover and greater ground cover of graminoids and shrubs. Our results demonstrate that although vegetation structure is important in determining site suitability, soil texture may be an overriding constraint limiting potential habitat for this species. Conservation actions for southeastern pocket gophers such as habitat restoration and population translocations should ensure that target sites have suitable low-clay soils.","PeriodicalId":50802,"journal":{"name":"American Midland Naturalist","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41961769","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-10-01DOI: 10.1637/0003-0031-184.2.129
H. Rowe, Tiffany A. Sprague, J. Broatch, D. Gruber, Debbie Langenfeld, L. Rivera
Abstract. Recovery of degraded lands in arid environments is especially challenging due to difficulty of matching ideal conditions to seed germination requirements and reduced native soil seed banks. Restoration practitioners try to overcome these challenges through seeding and site preparation treatments. In the McDowell Sonoran Preserve, Scottsdale, Arizona, the focus for restoring old roads was on seeding, cactus transplants, and soil treatments (either ripping or adding soil from nearby construction areas). Here we evaluated the success of these restoration sites 5–8 y after project completion. We compared vegetation and ground cover on eight roads that received a combination of these restoration treatments with adjacent reference areas. Plant cover was similar between the restoration and reference plots, but plant composition was different. The restoration plots contained more cacti due to cactus transplants, whereas the reference areas contained more shrub cover. The number of native plant species was greater in the reference areas than in the restoration plots. Seeding treatment had little effect, with only five of 11 seeded species appearing in plots, and only one species, Bouteloua aristidoides, appeared in both treatments that included seeding. Although cacti may have contributed to overall plant cover, they did not appear to aid establishment of other plants. Our findings suggest more interventions are likely required for the restoration and reference plant communities to converge in arid environments. We suggest considering multiple seeding treatments that will maximize the potential for ideal germination conditions and additional local interventions that may help accumulate litter and protect seeds.
{"title":"Lessons Learned 5+ Years After Transplanting and Seeding Restoration Sites in the Sonoran Desert, U.S.A.","authors":"H. Rowe, Tiffany A. Sprague, J. Broatch, D. Gruber, Debbie Langenfeld, L. Rivera","doi":"10.1637/0003-0031-184.2.129","DOIUrl":"https://doi.org/10.1637/0003-0031-184.2.129","url":null,"abstract":"Abstract. Recovery of degraded lands in arid environments is especially challenging due to difficulty of matching ideal conditions to seed germination requirements and reduced native soil seed banks. Restoration practitioners try to overcome these challenges through seeding and site preparation treatments. In the McDowell Sonoran Preserve, Scottsdale, Arizona, the focus for restoring old roads was on seeding, cactus transplants, and soil treatments (either ripping or adding soil from nearby construction areas). Here we evaluated the success of these restoration sites 5–8 y after project completion. We compared vegetation and ground cover on eight roads that received a combination of these restoration treatments with adjacent reference areas. Plant cover was similar between the restoration and reference plots, but plant composition was different. The restoration plots contained more cacti due to cactus transplants, whereas the reference areas contained more shrub cover. The number of native plant species was greater in the reference areas than in the restoration plots. Seeding treatment had little effect, with only five of 11 seeded species appearing in plots, and only one species, Bouteloua aristidoides, appeared in both treatments that included seeding. Although cacti may have contributed to overall plant cover, they did not appear to aid establishment of other plants. Our findings suggest more interventions are likely required for the restoration and reference plant communities to converge in arid environments. We suggest considering multiple seeding treatments that will maximize the potential for ideal germination conditions and additional local interventions that may help accumulate litter and protect seeds.","PeriodicalId":50802,"journal":{"name":"American Midland Naturalist","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48538018","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-10-01DOI: 10.1637/0003-0031-184.2.248
K. A. Haberyan
Abstract. Mozingo Lake was sampled monthly for 4 y following its impoundment in order to further understand trophic upsurges and to refine the classic model of upsurges. Upsurge 1 occurred in Month 8, when lake area increased by 184% and inundated only floodplain with comparable coverages of forest, cropland, and grassland (30%–33% each). At this time nitrate increased dramatically and was related to both precipitation and lake area increase, likely due to ammonia-based fertilizers from the flooded cropland. Phytoplankton biovolume remained low, however, likely due to the abundance of Daphnia and other zooplankton grazers. After recovery, the lake expanded dramatically again in Month 21 (Upsurge 2); lake area increased by 36%, but this expansion flooded land with less floodplain (23%) and with different proportions of land use (45% grassland, 31% forest, 14% cropland). Upsurge 2 experienced initial increases in nitrate and zooplankton, but these were minor compared to Upsurge 1, and phytoplankton remained low. These initial responses were followed by substantial increases in phosphate, which related to lake area increase; cyanobacteria biovolume expanded, but zooplankton abundance declined. Therefore the two upsurges were driven by different factors: nitrate in Upsurge 1, but phosphate in Upsurge 2. These drivers, in turn, may reflect differences in the newly-flooded land, including differences in land use and in landscape position (i.e., slope). In addition to seasonal succession, the phytoplankton of Mozingo Lake exhibited longer-term primary succession that related first to nitrate, then to grazing, then to multiple factors, suggesting increases in food web complexity. In contrast to the classic model of upsurges, the biotic responses in Mozingo Lake were quite transitory, and the nature of the upsurges varied with the characteristics of the newly-inundated land. Therefore, it appears that trophic upsurge is more variable than the classic model suggests.
{"title":"Two Trophic Upsurges With Differing Responses During the Filling of a Mid-Continental Reservoir (Mozingo Studies III)","authors":"K. A. Haberyan","doi":"10.1637/0003-0031-184.2.248","DOIUrl":"https://doi.org/10.1637/0003-0031-184.2.248","url":null,"abstract":"Abstract. Mozingo Lake was sampled monthly for 4 y following its impoundment in order to further understand trophic upsurges and to refine the classic model of upsurges. Upsurge 1 occurred in Month 8, when lake area increased by 184% and inundated only floodplain with comparable coverages of forest, cropland, and grassland (30%–33% each). At this time nitrate increased dramatically and was related to both precipitation and lake area increase, likely due to ammonia-based fertilizers from the flooded cropland. Phytoplankton biovolume remained low, however, likely due to the abundance of Daphnia and other zooplankton grazers. After recovery, the lake expanded dramatically again in Month 21 (Upsurge 2); lake area increased by 36%, but this expansion flooded land with less floodplain (23%) and with different proportions of land use (45% grassland, 31% forest, 14% cropland). Upsurge 2 experienced initial increases in nitrate and zooplankton, but these were minor compared to Upsurge 1, and phytoplankton remained low. These initial responses were followed by substantial increases in phosphate, which related to lake area increase; cyanobacteria biovolume expanded, but zooplankton abundance declined. Therefore the two upsurges were driven by different factors: nitrate in Upsurge 1, but phosphate in Upsurge 2. These drivers, in turn, may reflect differences in the newly-flooded land, including differences in land use and in landscape position (i.e., slope). In addition to seasonal succession, the phytoplankton of Mozingo Lake exhibited longer-term primary succession that related first to nitrate, then to grazing, then to multiple factors, suggesting increases in food web complexity. In contrast to the classic model of upsurges, the biotic responses in Mozingo Lake were quite transitory, and the nature of the upsurges varied with the characteristics of the newly-inundated land. Therefore, it appears that trophic upsurge is more variable than the classic model suggests.","PeriodicalId":50802,"journal":{"name":"American Midland Naturalist","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2020-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42000271","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-16DOI: 10.1637/0003-0031-184.1.73
Bree L. Richardson, K. Herrman
Abstract. Aquatic ecosystems with long hydraulic residence times (e.g., wetlands and reservoirs) can be important nitrogen (N) sinks via denitrification. The objective of this study was to examine denitrification rates of two small reservoirs (Springville and McDill) in central Wisconsin. Sediments, water chemistry, and discharge data were collected once per month between May and September of 2014 to achieve these objectives. Denitrification rates and microbial biomass carbon were not different between Springville and McDill; however, organic matter was significantly higher in McDill. Average denitrification rates were low at both sites, but ranged widely in Springville (0–23.72 mg N m–2 h–1) and less so in McDill (0.32–12.16 23 mg N m–2 h–1). Low denitrification rates in Springville may be the result of several locations being organic matter limited, whereas the McDill site was likely nitrate limited. Results from this study suggest reservoirs in central Wisconsin that are groundwater fed with sandy substrate have the potential to be nitrate sinks, but variation in the landscape (e.g. land use) and within each reservoir is influencing the magnitude of realized denitrification capabilities.
摘要水力停留时间长的水生生态系统（如湿地和水库）可以通过反硝化作用成为重要的氮汇。本研究的目的是检测威斯康星州中部两个小型水库（斯普林维尔和麦克迪尔）的脱氮率。为了实现这些目标，在2014年5月至9月期间每月收集一次沉积物、水化学和排放数据。Springville和McDill的反硝化率和微生物生物量碳没有差异；然而，麦克迪尔的有机质含量明显较高。两个地点的平均脱氮率都很低，但斯普林维尔的脱氮率范围很广（0–23.72 mg N m–2 h–1），而麦克迪尔的脱氮效率则较低（0.32–12.16 23 mg N m-2 h–2）。斯普林维尔的低脱氮率可能是由于几个地区的有机物有限，而麦克迪尔地区的硝酸盐可能有限。这项研究的结果表明，威斯康星州中部以沙质基质为地下水补给的水库有可能成为硝酸盐汇，但景观（如土地利用）和每个水库内部的变化正在影响实现的反硝化能力的大小。
{"title":"Nitrogen Removal via Denitrification in Two Small Reservoirs in Central Wisconsin, U.S.A.","authors":"Bree L. Richardson, K. Herrman","doi":"10.1637/0003-0031-184.1.73","DOIUrl":"https://doi.org/10.1637/0003-0031-184.1.73","url":null,"abstract":"Abstract. Aquatic ecosystems with long hydraulic residence times (e.g., wetlands and reservoirs) can be important nitrogen (N) sinks via denitrification. The objective of this study was to examine denitrification rates of two small reservoirs (Springville and McDill) in central Wisconsin. Sediments, water chemistry, and discharge data were collected once per month between May and September of 2014 to achieve these objectives. Denitrification rates and microbial biomass carbon were not different between Springville and McDill; however, organic matter was significantly higher in McDill. Average denitrification rates were low at both sites, but ranged widely in Springville (0–23.72 mg N m–2 h–1) and less so in McDill (0.32–12.16 23 mg N m–2 h–1). Low denitrification rates in Springville may be the result of several locations being organic matter limited, whereas the McDill site was likely nitrate limited. Results from this study suggest reservoirs in central Wisconsin that are groundwater fed with sandy substrate have the potential to be nitrate sinks, but variation in the landscape (e.g. land use) and within each reservoir is influencing the magnitude of realized denitrification capabilities.","PeriodicalId":50802,"journal":{"name":"American Midland Naturalist","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2020-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49245865","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-16DOI: 10.1637/0003-0031-184.1.98
Rex Meade Strange
Abstract. The reproductive biology of lampreys is of special interest given the group has retained many developmental features reminiscent of the earliest vertebrates. Herein I report spawning behavior in the Least Brook Lamprey (Lampetra aepyptera) from southern Indiana and provide descriptions of its embryonic development. Nesting activities began in mid-March when water temperatures ranged from 10 to 12 C, as two or more individuals dug out shallow depressions in loose gravel immediately above riffles. Communal spawning groups (>10 individuals) subsequently formed at the nest sites when the water temperature rose above 12 C. Embryos generated from the gametes of spawning adults underwent gastrulation 72 h after fertilization, neurulation after 6 d, and hatched after 14 d. Prolarvae developed melanophores 19 d after fertilization, eyespots were visible by 20 d, and the velum began to beat 25 d after fertilization. Expulsion of yolk from the intestine and filter feeding occurred 26 d after fertilization. Embryonic development in L. aepyptera largely matches the embryonic stages established for the Sea Lamprey (Petromyzon marinus), with subtle differences in the sequence of specific developmental features. These descriptions clarify conflicting accounts of spawning activities for L. aepyptera and provide staging criteria for future investigations into its embryonic development.
{"title":"Spawning and Embryonic Development of the Least Brook Lamprey (Lampetra aepyptera)","authors":"Rex Meade Strange","doi":"10.1637/0003-0031-184.1.98","DOIUrl":"https://doi.org/10.1637/0003-0031-184.1.98","url":null,"abstract":"Abstract. The reproductive biology of lampreys is of special interest given the group has retained many developmental features reminiscent of the earliest vertebrates. Herein I report spawning behavior in the Least Brook Lamprey (Lampetra aepyptera) from southern Indiana and provide descriptions of its embryonic development. Nesting activities began in mid-March when water temperatures ranged from 10 to 12 C, as two or more individuals dug out shallow depressions in loose gravel immediately above riffles. Communal spawning groups (>10 individuals) subsequently formed at the nest sites when the water temperature rose above 12 C. Embryos generated from the gametes of spawning adults underwent gastrulation 72 h after fertilization, neurulation after 6 d, and hatched after 14 d. Prolarvae developed melanophores 19 d after fertilization, eyespots were visible by 20 d, and the velum began to beat 25 d after fertilization. Expulsion of yolk from the intestine and filter feeding occurred 26 d after fertilization. Embryonic development in L. aepyptera largely matches the embryonic stages established for the Sea Lamprey (Petromyzon marinus), with subtle differences in the sequence of specific developmental features. These descriptions clarify conflicting accounts of spawning activities for L. aepyptera and provide staging criteria for future investigations into its embryonic development.","PeriodicalId":50802,"journal":{"name":"American Midland Naturalist","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2020-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46080091","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2020-07-01DOI: 10.1637/0003-0031-184.1.17
R. Naczi, T. Barger, D. Spaulding, Matthew R. Naczi, Jenna E. Dorey, J. Triplett
Abstract. Jackson County is the northeasternmost county of Alabama, U.S.A., and falls entirely in the southern portion of the Appalachian Plateaus physiographic province. Based on multiple years of fieldwork, herbarium work, and review of online (digitized) specimens, this study presents the diversity, habitats, biogeography, and conservation status of Carex in Jackson County. We document 90 Carex taxa from Jackson County by voucher specimens deposited in multiple herbaria. This value exceeds the number of taxa known from other, similar-sized regions in the southern part of the Appalachian Plateaus. Carex albicans var. emmonsii is a new state record and is known in Alabama only from Jackson County. We encountered high numbers of misidentifications among specimens collected prior to this study and exclude nine taxa previously reported from Jackson County that are based on misidentifications. Carex plants grow in a great number of habitats in Jackson County, with two hosting the greatest number of taxa: mature, wet-mesic, deciduous, floodplain forests on clays and clay loams; and mature, mesic, calcium-rich, deciduous, upland forests on loams. Jackson County is a nexus for both southeastern endemics and taxa occurring at or near their southern limits. Thirteen of the Carex taxa are rare in Alabama and likely of conservation concern in the state. This study contributes fundamental knowledge that makes sedge diversity, ecology, geography, and conservation better known, and is especially important for revealing a significant center of Carex diversity in North America.
{"title":"Revealing a Significant Center of Sedge Diversity: Carex (Cyperaceae) of Jackson County, Alabama, U.S.A.","authors":"R. Naczi, T. Barger, D. Spaulding, Matthew R. Naczi, Jenna E. Dorey, J. Triplett","doi":"10.1637/0003-0031-184.1.17","DOIUrl":"https://doi.org/10.1637/0003-0031-184.1.17","url":null,"abstract":"Abstract. Jackson County is the northeasternmost county of Alabama, U.S.A., and falls entirely in the southern portion of the Appalachian Plateaus physiographic province. Based on multiple years of fieldwork, herbarium work, and review of online (digitized) specimens, this study presents the diversity, habitats, biogeography, and conservation status of Carex in Jackson County. We document 90 Carex taxa from Jackson County by voucher specimens deposited in multiple herbaria. This value exceeds the number of taxa known from other, similar-sized regions in the southern part of the Appalachian Plateaus. Carex albicans var. emmonsii is a new state record and is known in Alabama only from Jackson County. We encountered high numbers of misidentifications among specimens collected prior to this study and exclude nine taxa previously reported from Jackson County that are based on misidentifications. Carex plants grow in a great number of habitats in Jackson County, with two hosting the greatest number of taxa: mature, wet-mesic, deciduous, floodplain forests on clays and clay loams; and mature, mesic, calcium-rich, deciduous, upland forests on loams. Jackson County is a nexus for both southeastern endemics and taxa occurring at or near their southern limits. Thirteen of the Carex taxa are rare in Alabama and likely of conservation concern in the state. This study contributes fundamental knowledge that makes sedge diversity, ecology, geography, and conservation better known, and is especially important for revealing a significant center of Carex diversity in North America.","PeriodicalId":50802,"journal":{"name":"American Midland Naturalist","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48874957","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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