Kellogg Biological Station Research Articles

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Eubacterial communities in different soil macroaggregate environments and cropping systems

Different positions within soil macroaggregates, and macroaggregates of different sizes, have different chemical and physical properties which could affect microbial growth and interactions among taxa. The hypothesis that these soil aggregate fractions contain different eubacterial communities was tested using terminal restriction fragment length polymorphism (T-RFLP) of the 16S ribosomal gene. Communities were characterized from two field experiments, located at the Kellogg Biological Station (KBS), MI, USA and the Ohio Agricultural Research and Development Center (OARDC), Wooster, OH, USA. Three soil management regimes at each site were sampled and management was found to significantly affect T-RFLP profiles. The soil aggregate erosion (SAE) method was used to isolate aggregate regions (external and internal regions). Differences between eubacterial T-RFLP profiles of aggregate exteriors and interiors were marginally significant at KBS (accounting for 12.5% of total profile variance), and not significant at OARDC. There were no significant differences among macroaggregate size classes at either site. These results are in general agreement with previous studies using molecular methods to examine microbial communities among different soil macroaggregate size fractions, although further study of communities within different aggregate regions is warranted. Analysis of individual macroaggregates revealed large inter-aggregate variability in community structure. Hence the tertiary components of soil structure, e.g. arrangement of aggregates in relation to shoot residue, roots, macropores, etc., may be more important than aggregate size or intra-aggregate regions in the determination of the types of microbial communities present in aggregates. Direct microscopic counts were also used to examine the bacterial population size in aggregate regions at KBS. The proportion of bacterial cells with biovolumes >0.18 μm 3 was higher in aggregate interiors than in exteriors, indicating potentially higher activity in that environment. This proportion was significantly related to percent C of the samples, while total bacterial cell counts were not.

Soil organic carbon pool changes following land‐use conversions

AbstractCarbon (C) can be sequestered in the mineral soil after the conversion of intensively cropped agricultural fields to more extensive land uses such as afforested and natural succession ecosystems. Three land‐use treatments from the long‐term ecological research site at Kellogg biological station in Michigan were compared with a nearby deciduous forest. Treatments included a conventionally tilled cropland, a former cropland afforested with poplar for 10 years and an old field (10 years) succession. We used soil aggregate and soil organic matter fractionation techniques to isolate C pools that (1) have a high potential for C storage and (2) accumulate C at a fast rate during afforestation or succession. These fractions could serve as sensitive indicators for the total change in C content due to land‐use changes. At the mineral soil surface (0–7 cm), afforesting significantly increased soil aggregation to levels similar to native forest. However, surface soil (0–7 cm) C did not follow this trend: soil C of the native forest site (22.9 t C ha−1) was still significantly greater than the afforested (12.6 t C ha−1) and succession (15.4 t C ha−1) treatments. However, when the 0–50 cm soil layer was considered, no differences in total soil C were observed between the cropland and the poplar afforested system, while the successional system increased total soil C (0–50 cm) at a rate of 0.786 t C ha−1 yr−1. Afforested soils sequestered C mainly in the fine intra‐aggregate particulate organic matter (POM) (53–250 μm), whereas the successional soils sequestered C preferentially in the mineral‐associated organic matter and fine intra‐aggregate POM C pools.

WEED ABOVEGROUND AND SEEDBANK COMMUNITY RESPONSES TO AGRICULTURAL MANAGEMENT SYSTEMS

The development of integrated weed management programs requires a clear understanding of the factors and mechanisms conditioning weed community dynamics in agroecosystems. This study evaluated the effect of different agricultural management systems on the aboveground and seedbank weed communities in annual row crops at the Long Term Ecological Research project in agricultural ecology at the W. K. Kellogg Biological Station, Michigan, USA. Weed biomass and species composition were sampled for six years over two corn–soybean–wheat sequence cycles in four agricultural management systems: (1) conventional (high external chemical input, moldboard plowed); (2) no-till (high external chemical input, no tillage); (3) low-input (low external chemical input, moldboard plowed); and (4) organic (no external chemical input, moldboard plowed). A greenhouse germination study assessed variation in the abundance and composition of the weed seedbank across the studied systems in the first and sixth year of this study. Abov...

The Structure of Microbial Communities in Soil and the Lasting Impact of Cultivation.

The structure of microbial communities was examined as a function of community composition and the relative abundance of specific microbial groups to examine the effects that plant community composition and land-use history have on microbial communities in the soil. The sites sampled were part of the Long Term Ecological Research (LTER) project in agricultural ecology at the W.K. Kellogg Biological Station of Michigan State University (Hickory Corners, MI) and included both active and abandoned agricultural fields as well as nearby fields that had never been cultivated. Microbial community structure was assessed by extracting total RNA from soil samples and using 16S rRNA-targeted oligonucleotide probes to quantify the abundance of rRNA from the alpha, beta, and gamma Proteobacteria, the Actinobacteria (Gram positive bacteria with a high mol % G+C genome), the Bacteria, and the Eukarya. In addition, soil microbial communities were characterized by examining fluorescently tagged terminal restriction fragment length polymorphisms (T-RFLP) in PCR amplified 16S rDNA. Microbial community structure was observed to be remarkably similar among plots that shared a long-term history of agricultural management despite differences in plant community composition and land management that have been maintained on the plots in recent years. In contrast, microbial community structure differed significantly between fields that had never been cultivated and those having a long-term history of cultivation.

Weed Suppression by Annual Legume Cover Crops in No‐Tillage Corn

Cover crops often reduce density and biomass of annual weeds in no‐till cropping systems. However, cover crops that over‐winter also have the potential to reduce crop yield. Currently, there is an interest in annual medics (Medicago spp.) and other annual legumes that winter‐kill for use as cover crops in midwestern grain cropping systems. A 2‐yr study was conducted at East Lansing and the Kellogg Biological Station, Michigan, to investigate the influence of annual legume cover crops on weed populations. Two annual medic species [burr medic (M. polymorpha cv. Santiago) and barrel medic (M. truncatula Gaertn. cv. Mogul)], berseem clover (Trifolium alexandrinum L. cv. Bigbee), and medium red clover (Trifolium pratense L.) were no‐till seeded as cover crops into winter wheat (Triticum aestivum L.) stubble in a winter wheat/corn (Zea mays L.) rotation system. Density of winter annual weeds were between 41 and 78% lower following most cover crops when compared with no cover control in 2 out of 4 site years, while dry weight was between 26 and 80% lower in all 4 site years. Impact of cover crops on the density of summer annual weeds was infrequent; however, weed dry weights were reduced by 70% in 1995 following burr medic and barrel medic. Dry weight of perennial weeds before corn planting were 35 to 75% lower following annual legumes compared with the control, while weed density was not affected. This study indicated a potential for annual legumes to reduce weed density and growth in no‐till corn grain systems.

Hematozoa of Waterfowl from Michigan

Two hundred eighteen and 127 wild waterfowl (Anatidae) of five species were sampled from the Kellogg Biological Station area (Michigan, USA) during the summer (1 June to 24 August 1995) and fall (9 September to 8 October 1995), respectively. Twelve (6%) of those sampled in summer and 13 (11%) sampled in the fall were infected with hemosporids. Haemoproteus nettionis, Haemoproteus greineri, and Leucocytozoon simondi infected both summer and fall birds, with H. nettionis the most common (4% summer; 7% fall). Mean intensities were low; the highest mean intensity was 4.6+/-1.1 gametocytes per 5,000 uninfected erythrocytes for H. nettionis in summer. Of 123 local waterfowl, none were infected with any blood parasite. Thirty-five captive year-round resident waterfowl also were sampled and no blood parasites were found.

Resource competition and suppression of plants colonizing early successional old fields

Early colonizing annual plants are rapidly suppressed in secondary succession on fertile midwestern old fields, while later colonizing perennials persist. Differences in competitive ability for above- and belowground resources may be partly responsible for differences in species persistence during succession, as both light and nutrient availability may change rapidly. We found that, although both above- and belowground competition suppress growth of colonizing plants, belowground competition was the dominant factor in the suppression of the annual Ambrosia artemisiifolia in 2nd-year-old fields near the W.K. Kellogg Biological Station in southwestern Michigan. Despite an ability to persist in later successional fields, seedling transplants of the perennial Achillea millefolium were also suppressed by above- and belowground competition, with belowground competition having the strongest effect. As in many old fields, nitrogen availability is the primary factor limiting plant productivity. There was no clear difference between the species in ability to compete for (15)N from an enriched patch, although there was an indication of greater precision of foraging by Achillea. Life history differences between these species and consequent differences in the phenology of root growth relative to other old-field plants are likely to play a large role in the persistence of Achillea in successional fields where Ambrosia is suppressed.

Phylogenetic analysis of nonthermophilic members of the kingdom crenarchaeota and their diversity and abundance in soils

Within the last several years, molecular techniques have uncovered numerous 16S rRNA gene (rDNA) sequences which represent a unique and globally distributed lineage of the kingdom Crenarchaeota that is phylogenetically distinct from currently characterized crenarchaeotal species. rDNA sequences of members of this novel crenarchaeotal group have been recovered from low- to moderate-temperature environments (-1.5 to 32 degreesC), in contrast to the high-temperature environments (temperature, >80 degreesC) required for growth of the currently recognized crenarchaeotal species. We determined the diversity and abundance of the nonthermophilic members of the Crenarchaeota in soil samples taken from cultivated and uncultivated fields located at the Kellogg Biological Station's Long-Term Ecological Research site (Hickory Corners, Mich.). Clones were generated from 16S rDNA that was amplified by using broad-specificity archaeal PCR primers. Twelve crenarchaeotal sequences were identified, and the phylogenetic relationships between these sequences and previously described crenarchaeotal 16S rDNA sequences were determined. Phylogenetic analyses included nonthermophilic crenarchaeotal sequences found in public databases and revealed that the nonthermophilic Crenarchaeota group is composed of at least four distinct phylogenetic clusters. A 16S rRNA-targeted oligonucleotide probe specific for all known nonthermophilic crenarchaeotal sequences was designed and used to determine their abundance in soil samples. The nonthermophilic Crenarchaeota accounted for as much as 1.42% +/- 0.42% of the 16S rRNA in the soils analyzed.

Annual Medics and Berseem Clover as Emergency Forages

AbstractSevere winter‐kill of alfalfa (Medicago sativa L.) in some years prompts the need for emergency forages in northern locations. Three annual medic species—barrel medic (M. truncatula Gaertn. cv. Mogul), burr medic (M. polymorpha L. cv. Santiago), and snail medic [M. scutellata (L.) Mill. cv. Sava]—and berseem clover (Trifolium alexandrinum L. cv. Bigbee) and ‘Nitro’ alfalfa were seeded in early spring at East Lansing and the Kellogg Biological Station (KBS) in Michigan in 1994 and 1995. Forage mass was measured at first harvest 60 d after planting and at second harvest 30 d later. Forage mass of annual medics at first harvest ranged from 0.8 to 3.6 Mg ha−1 across locations and years. Berseem clover produced an average forage mass of 2.2 Mg ha−1 at first harvest, which was similar to alfalfa. Crude protein (CP) concentration of annual medics, berseem, and alfalfa ranged from 111 to 210,178 to 233, and 170 to 218 g kg−1, respectively, at first harvest. Regrowth of annual medics (except Mogul) was less than alfalfa or berseem clover; however, the regrowth of Mogul was decumbent and not suitable as hay. Average forage mass and CP concentration of berseem at second harvest was 1.8 Mg ha−1 and 191 g kg−1, respectively, which was similar to alfalfa. Our results indicate that both annual medics and berseem clover can be used as emergency forages in northern locations; however, annual medics have the potential for only one harvest, whereas berseem can be harvested twice during the growing season.

Pollination Reviewed

EcologyVolume 78, Issue 1 p. 327-328 Book Review Pollination Reviewed Jeffrey K. Conner, Jeffrey K. Conner Michigan State University, Kellogg Biological Station, 3700 East Gull Lake Drive, Hickory Corners, Michigan 49060Search for more papers by this author Jeffrey K. Conner, Jeffrey K. Conner Michigan State University, Kellogg Biological Station, 3700 East Gull Lake Drive, Hickory Corners, Michigan 49060Search for more papers by this author First published: 01 January 1997 https://doi.org/10.1890/0012-9658(1997)078[0327:PR]2.0.CO;2Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat Volume78, Issue1January 1997Pages 327-328 RelatedInformation

Alfalfa Establishment with and without Spring-Applied Herbicides

No-till establishment of alfalfa (Medicago sativa L.) has increased significantly over the past decade, yet few studies have documented the effect of herbicide use at establishment on notill establishment-year yield and forage quality. Studies conducted in Michigan in 1989 and 1990 compared alfalfa establishment by conventional and no-tillage methods. Four establishment herbicide treatments (no herbicide, paraquat, paraquat + 2,4-DB, paraquat + EPTC + 2,4-DB) were compared with-in each tillage system. Treatments were evaluated by determining alfalfa plant population, forage yield, species composition, forage quality, and net economic return

An Internet botanical specimen data server

SummaryBeach, J. H., Ozminski, S. J. & Boufford, D. E.: An Internet botanical specimen data server. – Taxon 42: 627–629. 1993. – ISSN 0040‐0262.The E‐mail data server is a database system that delivers specimen data over the Internet within electronic mail. Using electronic mail as a vehicle for delivering queries and for returning data permits unlimited access to remote databases for any scientist with network mail service. This “open‐access” approach contrasts with database systems which require pre‐arranged accounts and passwords for access, and takes advantage of existing research data networks. Three specimen databases are available for queries: (1) type specimens of the Lamiaceae (and soon other families) in the Harvard University herbaria, (2) the complete catalog of Michigan State University's Kellogg Biological Station herbarium, and (3) the Flora of Mt. Kinabalu (Borneo) specimen database.

Assessing nematode communities in agroecosystems of varying human intervention

The effect of disturbance on soil nematode communities was studied in eight treatments varying in intensity of human intervention at the Kellogg Biological Station Long Term Ecological Research site, Hickory Corners, MI. The agricultural treatments ranged from those manipulated with high chemical inputs and heavily impacted by human management to successional treatments that had no chemicals and little human impact. A canonical discriminant analysis of the nematode data separated the treatments into four systems: high chemical input (the conventional tillage and no tillage treatments, both corn/soybean rotations); organic (the low input and zero input treatments, both wheat/corn/soybean rotations); perennial (poplar and alfalfa treatments); successional (abandoned after tillage and never tilled treatments). Nematode abundance was highest in the high input and organic systems and lowest in the poplar treatment. Overall, bacterial feeding, plant parasitic and fungal feeding nematodes dominated the treatments. Species diversity was greatest in the successional treatments. The bacterial feeding trophic group and the modified Shannon index described differences at both the treatment and system levels, while the Shannon index demonstrated diversity at the system and annual and perennial crop level of analysis. Measures that detected differences ( P < 0.05) consistently across all treatments, systems, and annual vs. perennial crops were total abundance, the predator trophic group, the maturity index (MI) and the plant parasite index. The minimum analyses needed to detect disturbance reliably were a multivariate analysis and the MI. However, understanding and predicting the impact of the disturbance on the food web and ecosystem functioning would be increased with results from diversity indices and nematode functional groups.

The influence of market demand upon innovation: A critical review of some recent empirical studies

While there has been long-term interest in identifying agricultural practices which promote soil ecological services, there remains little consensus on how practices such as low-input and organic impact soil microbial communities and their functions. In order to improve understanding of the response of soil microbial communities to shifts in agricultural management programs, a two year field study was conducted on large-scale conventional, low-input and organic fields associate with the Kellogg Biological Station, Long Term Ecological Research site near Kalamazoo, MI. Because large commercial agricultural fields typically exhibit diverse topography, plots were established in all fields at unique landscape positions to explore interactions between management and topographical position. Over the course of two growing seasons, differences in microbial biomass, extracellular enzyme production and carbon and nitrogen mineralization were quantified at different topographical positions (summits, slopes, and depressions) in each of the three agricultural management systems. Alone, management practices had little to no impact on soil microbial traits, however, significant management by landscape position and management by time interactions were observed for extracellular enzymes. Acid phosphatase activity on hill slopes was 35–52% greater in low input systems than in conventional and organic management systems. Similarly, spring amino peptidase activity was roughly 100% higher in low input than in organic systems. Landscape position also had substantial effects on both microbial biomass and enzyme activities. Topographical depressions exhibited significantly higher activities of β-N-acetylglucosaminadase, β-glucosidase, phenol oxidase and greater microbial biomass than summits and slopes (26%, 30%, 36%, and 55%, respectively). Similarly, peroxidase activity was approximately 38% greater in depressions and on summits than on hill slopes. Differences in microbial traits among positions were also negatively correlated with soil bulk density and sand content and positively correlated with clay, silt, carbon, nitrogen and moisture content. Our study stresses the importance of accounting for topographical heterogeneity when assessing the impact of management practices on belowground ecological function. Further, while management practices alone had little effect on soil microbial biomass and function, our study demonstrates that low input management programs may be beneficial for retaining microbial resources and thus promoting microbial activity on erosion-prone hill slopes.

Local Specialization of Phoretic Mites on Sympatric Carrion Beetle Hosts

Wide—ranging but ecologically variable species and their close relatives provide the best opportunity to analyze the role of trade—offs in specialization. Poecilochirus carabi Can. is a holarctically distributed mite that rides between patches of carrion on the bodies of carrion beetles (Silphidae, Nicropohorus). Using behavioral tests, we demonstrated differences in local host specialization of P. carabi at two sites in Michigan, the Kellogg Biological Station (KBS) and the University of Michigan Biological Station (UMBS). At KBS, Nicrophorus orbicollis and N. tomentosus each supported a strict host specialist. These KBS "orbicollis— and tomentosus—specialists" differed significantly in both body size and a measure of dorsal setal lengths. Laboratory crosses between specialists were not successful, suggesting that the specialists are distinct species. At UMBS, in contrast, such strong specialists were not found. Mites preferred two beetle species, N. tomentosus or N. defodiens (a species not found at KBS), over all others, but moved between these two species readily. UMBS mites all resembled the KBS tomentosus—specialist in morphology. No orbicollis—specialist mites were found at UMBS, despite the high relative abundance of N. orbicollis in the beetle community. We raised mites from each site on all available hosts to test whether preference for a host species was associated with higher fitness in association with that host species. Although P. carabi were able to reproduce in association with any Nicrophorus species, mites at UMBS had the highest reproductive success on the two species that they preferred. Each KBS specialist mite was raised in association with N. tomentosus and N. orbicollis. While the tomentosus—specialist had significantly higher reproductive success in association with its preferred host species, the orbicollis—specialist showed no difference in reproductive success between the two host species. However, when the pattern of dispersal on beetles was considered, a difference in fitness between the two hosts was apparent. This difference in dispersal pattern was due to an interaction between the parental behavior of the two host species and mite generation times. We discuss the evidence for trade—offs in this system and the use of interspecific comparisons in the analysis of specialization.

A Comparison of Methods for Estimating Seed Numbers in the Soil

(1) Seed-bank species composition and seed density were determined in an annually ploughed field at the Kellogg Biological Station in south-western Michigan, U.S.A. using three different methods: direct germination, germination following cold-stratification, and washing using a modified elutriation system. A fourth method, flotation on a salt-density gradient was abandoned after preliminary trials showed it was inefficient and inaccurate. (2) Twenty soil cores (2 5 cm in diameter, 15 cm deep) were taken from each of twentyfive sampling points in the field. Cores were divided into three depth intervals (0-2 cm, 2-5 cm and 5-15 cm) and five cores from each quarter of a sampling quadrat were combined and randomly assigned to one of the four methods for estimating the seed bank. (3) A total of fifty species was detected in the seed bank of this community. Overall, more species were detected with cold-stratification (forty-two species) than with direct germination (thirty-seven) or elutriation (thirty-five). Plots of species-sampling-area curves showed that fifteen to twenty sampling locations were sufficient to determine the number of species present in the seed bank with any of these methods. (4) Seed-density estimates were significantly higher in the elutriated samples. This was due primarily to the inclusion of inviable seeds in the counts from the elutriated samples. (5) There were significant differences in seed viability among species recovered in the elutriated samples. Both Ambrosia artemisiifolia and Chenopodium album, seeds of which were common in the samples, had low viability (25% and 3%, respectively). (6) Germination methods (particularly when more than one pre-treatment method is used) provide a more complete listing of species present in the soil seed bank of a community than elutriation. However, elutriation methods may be more useful for documenting variation in seed distributions on a large spatial scale or in quantifying the distribution of species with unique, easily identifiable seeds. Elutriation seems particularly well-suited for quantifying the distribution of plants that are considered weeds in agricultural systems, because many of these species have seeds that are easily identified and retain viability when dried.

Biology and Seasonal Occurrence of Manduca quinquemaculata and M. sexta (Lepidoptera: Sphingidae) in Southwestern Michigan

The seasonal occurrence and development of field populations of Manduca quinquemaculata (L.) and Manduca sexta (Haworth) were monitored at the Kellogg Biological Station in Barry County, Mich., from late June to early September during 1985 and 1986. Results indicated that initial and peak oviposition were variable between years for both species and were not predictable by accumulated degree-days (DD), base 10°C. In both years, initial egg deposition occurred slightly earlier for M. quinquemaculata than for M. sexta (DD 615 versus DD 728 in 1985 and DD 700 versus DD 742 in 1986), whereas peak oviposition was dependent upon the year in question. In 1985, oviposition for M. quinquemaculata peaked approximately 100 DD earlier than for M. sexta . In 1986, the reverse was observed. Larval development occurred at the same rate in both species and was closely associated with degree-day accumulation requiring, on the average, 39 DD per stadium. Monitoring data from both years indicated that M. quinquemaculata is likely univoltine in Michigan whereas M. sexta is probably bivoltine.

Quantifying the Nitrogen Contribution from Alfalfa to Soil and Two Succeeding Crops Using Nitrogen‐15

AbstractWith the current interest in sustainable agricultural systems, the use of legumes in crop rotations to provide N to subsequent crops is increasing. The objective of this study was to quantify the N contribution from different alfalfa (Medicago sativa L.) plant parts to a subsequent corn (Zea mays L.) crop, various soil fractions, and a 2nd yr spring barley (Hordeum vulgare L.) crop. The study was conducted at two field locations in Michigan, on a Capac loam (fineloamy, mixed, mesic, Aerie Ochraqualf) in East Lansing (EL) and on an Oshtemo sandy loam (coarse‐loamy, mixed, mesic, Typic Hapludalf) at the Kellogg Biological Station (KBS) in Hickory Corners. Alfalfa shoots and roots/crowns labeled with 15N were applied separately to microplots in Fall 1985 and Spring 1986 at a rate equivalent to 112 kg N ha−1. Corn was harvested and soil was sampled from all microplots in Fall 1986 and analyzed for 15N. Corn recovered 17 and 25% of the alfalfa‐15N applied to the loam and sandy loam soils at ELand KBS, respectively. Alfalfa‐15N remaining in soil averaged 46% of the initial input for both locations. Most (96%) of the alfalfa‐15N remaining in soil was recovered in the organic fraction, with microbial biomass accounting for 18% of this recovery. More 15N was recovered by corn and in soil from alfalfa shoots than roots/crowns at both locations, and from spring‐incorporated than fall‐incorporated plant material on the loam soil. Only 1% of the alfalfa‐15N from the original application was recovered by a 2nd yr spring barley crop at both locations

Announcing the Eminent Ecologist Seminar Series at the W. K. Kellogg Biological Station Summer 1989

Announcing the Eminent Ecologist Seminar Series at the W. K. Kellogg Biological Station Summer 1989