From the moment of its inception, human choice about how to treat the environment is a key part o... more From the moment of its inception, human choice about how to treat the environment is a key part of ecological restoration. Because many, if not most, restoration projects require continual management once established, human choice remains a vital component of restoration projects for their entire life. But ecological restorationists often downplay the role of choice in restoration, partly because we see the choice to restore as obvious and inherently good and partly because we feel the restoration of more natural conditions for a habitat will lessen the impact of human choice over time. Some critics feel the role of human choice in restoration degrades the value of restoration. However, another response to human choice in restoration is to embrace choice, even with the problems it brings, and use choice as a way to more fully engage humans with the environment. If such choices are approached carefully, with recognition of the potential for poor choices, then restorationists can arrive at restorations that are better for both the environment and us.
Chamaecyparis thyoides (Atlantic white-cedar) swamps are in decline in the New Jersey Pinelands, ... more Chamaecyparis thyoides (Atlantic white-cedar) swamps are in decline in the New Jersey Pinelands, while Aeer rubrum (red maple) swamps are increasing. One possible reason for this occurrence may be differences in seedling recruitment of the two species. Seedling establishment of different species is expected to vary with physical conditions and requirements for safe sites. This study examined differences in seedling recruitment for C. thyoides and A. rubrum in the New Jersey Pinelands. A field survey of six C. thyoides swamps found that C. thyoides seedlings occur most often under an open or C. thyoides canopy on peaty, cedar needle covered soils or on mats of Sphagnum. In contrast, A. rubrum seedlings were most often found under A. rubrum canopies on Sphagnum mats or grass-dominated bottom areas. A greenhouse experiment was conducted to determine whether differences in microhabitat occupation were related to differences in growth of C. thyoides and A, rubrum seedlings. Seedlings were grown in different soil types (Sphagnum or peat) and at different water levels (inundated, saturated, or moist soil) typical of those found in C. thyoides swamps within the New Jersey Pinelands. Chamaecyparis thyoides experienced the greatest increase in height in moist soils and the least increase in height in inundated soils. Chamaecyparis thyoides achieved greater biomass than A. rubrum in peat soil, while A. rubrum had greater biomass in Sphagnum. These results indicate that C. thyoides and A. rubrum differ in conditions that are best for their seedling growth and that different management schemes may favor one species over the other.
Natural variability in the species composition of salt marsh plant assemblage was studied for 4 y... more Natural variability in the species composition of salt marsh plant assemblage was studied for 4 years (1986-90) at Bolinas Lagoon, California (USA). The study was conducted during a period in which little or no physical disturbance occurred in the marsh. During the study, Bolinas Lagoon experienced highly variable rainfall, both within and between years. In years with average or below average winter and spring rainfall, the cover of Salicornia virginica increased relative to that of the other species. During the one year with much higher than average spring rainfall, the cover of Salicornia declined and rare species increased in relative abundance. These patterns suggest that under typical marsh conditions, the plant assemblage experiences stress due to low availability of freshwater and high soil salinity. Under such conditions, the stress-tolerant Salicornia dominates the assemblage. If, however, there is abundant rainfall early in the growing season, the other species are released from stress and are able to increase in cover. The marsh of Bolinas Lagoon appears to be resistant to change and able to tolerate stress. Few studies have examined natural variability in species in undisturbed marshes and more of such studies must be made in order to understand whether or not marshes are in general resistant to change caused by rainfall variability.
Ecological restoration, North America, Mar 1, 2002
R estoration ecology had its genesis in the 1930s as Midwestern ecologists came to the realizatio... more R estoration ecology had its genesis in the 1930s as Midwestern ecologists came to the realization that nearly all the tallgrass prairie in Illinois, Iowa, and Wisconsin had been converted to agricultural or urban land uses (Curtis and Greene 1949, Critical Trends Assessment Project 1994, Smith 1998). While calls for preservation of remaining prairie in Iowa began by 1919 (Smith 1998), the pioneer restoration ecologists of the early 20th century recognized that if extensive areas of tallgrass prairie were going to be part of our future, they would have to begin to restore these historic grasslands. The first efforts were undertaken at the University of Wisconsin-Madison Arboretum, initially as experimental plots under the direction of biology professor Dr. Norman Passett, and later under the direction of Dr. Theodore Sperry and Dr. Henry Greene, Dr. Sperry led the restoration activity at Curtis Prairie-a planting effort that involved men from the Civilian Conservation Corps and lasted from 1936 through 1940-while Dr. Greene almost single-handedly planted Greene Prairie between 1943 and 1952 (Blewett and Cottam 1984). Their efforts served as the inspiration for the third tallgrass prairie restoration in the Midwest (Howell and Jordan, 1991) which took place at the Knox College Green Oaks Field Study Center in west-central Illinois.
Ecological restoration, North America, May 13, 2008
by the Board of Regents of the University of Wisconsin System. Restoration Notes Restoration Note... more by the Board of Regents of the University of Wisconsin System. Restoration Notes Restoration Notes have been a distinguishing feature of Ecological Restoration for more than 25 years. This section is geared towards introducing innovative research, tools, technologies, programs, and ideas, as well as providing short-term research results and updates on ongoing efforts. Please direct submissions and inquiries to the editorial staff (
The horizontal and vertical distributions of selected copepod species across the Gulf Stream in S... more The horizontal and vertical distributions of selected copepod species across the Gulf Stream in September 1982 were investigated along a transect east of Cape Hatteras where the Stream turns offshore. Copepod species distributions across the Stream, and the extent of their diel migrations, can be grouped into several distinct patterns associated with different environmental habitats within the Stream, some of which change depth across the Stream along sloping isopycnals. Copepod behavior, such as probable temperature and depth preferences and diel vertical migration, interacts with the complex physical structure of the Stream to determine at what depths in the water column a species is found at different crossstream locations. The different environmental habitats are also characterized by different current velocities and directions, and therefore the species groups experience different degrees of downstream and cross-stream transport. Direct cross-stream transport, in addition to mesoscale events such as ring formation, is a likely mechanism connecting some populations of Slope Water and Sargasso Sea zooplankton.
Ecological restoration, North America, Dec 1, 2004
ABSTRACT What do we mean to be doing when we talk about, plan, and carry out ecological restorati... more ABSTRACT What do we mean to be doing when we talk about, plan, and carry out ecological restorations? Restoration ecologists usually reply that our goal in restoration is to return an ecosystem to some previously existing condition that no longer is present at that site. We almost always make the assumption that the site's current condition is somehow degraded or less desirable than the previous condition and thus we need to improve the degraded condition of the site. Yet that assumption and our usual goal in restoration beg the question of what we mean by degraded, desirable and improvement. Furthermore, how do we decide when an ecosystem is so degraded or damaged that it is in need of restoration? What sort of values are we bringing to the process when we talk about restoration? What are we really doing when we restore an ecosystem? In this talk, I will concentrate on how we decide the final state that is the goal of our restoration efforts and what it means when we describe restorations using terms like natural and artificial. I will argue that by using terms like natural and artificial we are setting up a false dichotomy that separates us from the act of restoration and from a very important part of restoration – restoring the human relationship to the rest of the biota. Ideally restoration is an activity that can be engaged by almost all people working at small to large scales. We should do all we can to bridge that gulf and make restoration as appealing as possible to potential restorationists.
A series of experimental disturbances by sediment deposition were conducted in the salt marsh at ... more A series of experimental disturbances by sediment deposition were conducted in the salt marsh at Bolinas Lagoon to examine the ability of marsh plants to recover from small‐scale anthropogenic disturbances. Results from these experiments demonstrated that species differ in their ability to recover, with Distichlis spicata and Salicornia virginica recovering most quickly from disturbances that occurred at any time of the year. Other species, such as Frankenia grandifolia and Jaumea carnosa, only recovered from disturbances that occurred early in the growing season. Recovery was by vegetative ingrowth of plants surrounding a disturbed patch or by growth of buried plants up through the sediment. Seedling establishment was rare and did not significantly influence recovery. Anthropogenic disturbances such as excessive sedimentation may cause lasting changes by eliminating or reducing the cover of species sensitive to sediment deposition, and by changing the substrate so that recruitment from seeds is limited.
R estoration ecology had its genesis in the 1930s as Midwestern ecologists came to the realizatio... more R estoration ecology had its genesis in the 1930s as Midwestern ecologists came to the realization that nearly all the tallgrass prairie in Illinois, Iowa, and Wisconsin had been converted to agricultural or urban land uses (Curtis and Greene 1949, Critical Trends Assessment Project 1994, Smith 1998). While calls for preservation of remaining prairie in Iowa began by 1919 (Smith 1998), the pioneer restoration ecologists of the early 20th century recognized that if extensive areas of tallgrass prairie were going to be part of our future, they would have to begin to restore these historic grasslands. The first efforts were undertaken at the University of Wisconsin-Madison Arboretum, initially as experimental plots under the direction of biology professor Dr. Norman Passett, and later under the direction of Dr. Theodore Sperry and Dr. Henry Greene, Dr. Sperry led the restoration activity at Curtis Prairie-a planting effort that involved men from the Civilian Conservation Corps and lasted from 1936 through 1940-while Dr. Greene almost single-handedly planted Greene Prairie between 1943 and 1952 (Blewett and Cottam 1984). Their efforts served as the inspiration for the third tallgrass prairie restoration in the Midwest (Howell and Jordan, 1991) which took place at the Knox College Green Oaks Field Study Center in west-central Illinois.
From the moment of its inception, human choice about how to treat the environment is a key part o... more From the moment of its inception, human choice about how to treat the environment is a key part of ecological restoration. Because many, if not most, restoration projects require continual management once established, human choice remains a vital component of restoration projects for their entire life. But ecological restorationists often downplay the role of choice in restoration, partly because we see the choice to restore as obvious and inherently good and partly because we feel the restoration of more natural conditions for a habitat will lessen the impact of human choice over time. Some critics feel the role of human choice in restoration degrades the value of restoration. However, another response to human choice in restoration is to embrace choice, even with the problems it brings, and use choice as a way to more fully engage humans with the environment. If such choices are approached carefully, with recognition of the potential for poor choices, then restorationists can arrive at restorations that are better for both the environment and us.
Chamaecyparis thyoides (Atlantic white-cedar) swamps are in decline in the New Jersey Pinelands, ... more Chamaecyparis thyoides (Atlantic white-cedar) swamps are in decline in the New Jersey Pinelands, while Aeer rubrum (red maple) swamps are increasing. One possible reason for this occurrence may be differences in seedling recruitment of the two species. Seedling establishment of different species is expected to vary with physical conditions and requirements for safe sites. This study examined differences in seedling recruitment for C. thyoides and A. rubrum in the New Jersey Pinelands. A field survey of six C. thyoides swamps found that C. thyoides seedlings occur most often under an open or C. thyoides canopy on peaty, cedar needle covered soils or on mats of Sphagnum. In contrast, A. rubrum seedlings were most often found under A. rubrum canopies on Sphagnum mats or grass-dominated bottom areas. A greenhouse experiment was conducted to determine whether differences in microhabitat occupation were related to differences in growth of C. thyoides and A, rubrum seedlings. Seedlings were grown in different soil types (Sphagnum or peat) and at different water levels (inundated, saturated, or moist soil) typical of those found in C. thyoides swamps within the New Jersey Pinelands. Chamaecyparis thyoides experienced the greatest increase in height in moist soils and the least increase in height in inundated soils. Chamaecyparis thyoides achieved greater biomass than A. rubrum in peat soil, while A. rubrum had greater biomass in Sphagnum. These results indicate that C. thyoides and A. rubrum differ in conditions that are best for their seedling growth and that different management schemes may favor one species over the other.
Natural variability in the species composition of salt marsh plant assemblage was studied for 4 y... more Natural variability in the species composition of salt marsh plant assemblage was studied for 4 years (1986-90) at Bolinas Lagoon, California (USA). The study was conducted during a period in which little or no physical disturbance occurred in the marsh. During the study, Bolinas Lagoon experienced highly variable rainfall, both within and between years. In years with average or below average winter and spring rainfall, the cover of Salicornia virginica increased relative to that of the other species. During the one year with much higher than average spring rainfall, the cover of Salicornia declined and rare species increased in relative abundance. These patterns suggest that under typical marsh conditions, the plant assemblage experiences stress due to low availability of freshwater and high soil salinity. Under such conditions, the stress-tolerant Salicornia dominates the assemblage. If, however, there is abundant rainfall early in the growing season, the other species are released from stress and are able to increase in cover. The marsh of Bolinas Lagoon appears to be resistant to change and able to tolerate stress. Few studies have examined natural variability in species in undisturbed marshes and more of such studies must be made in order to understand whether or not marshes are in general resistant to change caused by rainfall variability.
Ecological restoration, North America, Mar 1, 2002
R estoration ecology had its genesis in the 1930s as Midwestern ecologists came to the realizatio... more R estoration ecology had its genesis in the 1930s as Midwestern ecologists came to the realization that nearly all the tallgrass prairie in Illinois, Iowa, and Wisconsin had been converted to agricultural or urban land uses (Curtis and Greene 1949, Critical Trends Assessment Project 1994, Smith 1998). While calls for preservation of remaining prairie in Iowa began by 1919 (Smith 1998), the pioneer restoration ecologists of the early 20th century recognized that if extensive areas of tallgrass prairie were going to be part of our future, they would have to begin to restore these historic grasslands. The first efforts were undertaken at the University of Wisconsin-Madison Arboretum, initially as experimental plots under the direction of biology professor Dr. Norman Passett, and later under the direction of Dr. Theodore Sperry and Dr. Henry Greene, Dr. Sperry led the restoration activity at Curtis Prairie-a planting effort that involved men from the Civilian Conservation Corps and lasted from 1936 through 1940-while Dr. Greene almost single-handedly planted Greene Prairie between 1943 and 1952 (Blewett and Cottam 1984). Their efforts served as the inspiration for the third tallgrass prairie restoration in the Midwest (Howell and Jordan, 1991) which took place at the Knox College Green Oaks Field Study Center in west-central Illinois.
Ecological restoration, North America, May 13, 2008
by the Board of Regents of the University of Wisconsin System. Restoration Notes Restoration Note... more by the Board of Regents of the University of Wisconsin System. Restoration Notes Restoration Notes have been a distinguishing feature of Ecological Restoration for more than 25 years. This section is geared towards introducing innovative research, tools, technologies, programs, and ideas, as well as providing short-term research results and updates on ongoing efforts. Please direct submissions and inquiries to the editorial staff (
The horizontal and vertical distributions of selected copepod species across the Gulf Stream in S... more The horizontal and vertical distributions of selected copepod species across the Gulf Stream in September 1982 were investigated along a transect east of Cape Hatteras where the Stream turns offshore. Copepod species distributions across the Stream, and the extent of their diel migrations, can be grouped into several distinct patterns associated with different environmental habitats within the Stream, some of which change depth across the Stream along sloping isopycnals. Copepod behavior, such as probable temperature and depth preferences and diel vertical migration, interacts with the complex physical structure of the Stream to determine at what depths in the water column a species is found at different crossstream locations. The different environmental habitats are also characterized by different current velocities and directions, and therefore the species groups experience different degrees of downstream and cross-stream transport. Direct cross-stream transport, in addition to mesoscale events such as ring formation, is a likely mechanism connecting some populations of Slope Water and Sargasso Sea zooplankton.
Ecological restoration, North America, Dec 1, 2004
ABSTRACT What do we mean to be doing when we talk about, plan, and carry out ecological restorati... more ABSTRACT What do we mean to be doing when we talk about, plan, and carry out ecological restorations? Restoration ecologists usually reply that our goal in restoration is to return an ecosystem to some previously existing condition that no longer is present at that site. We almost always make the assumption that the site's current condition is somehow degraded or less desirable than the previous condition and thus we need to improve the degraded condition of the site. Yet that assumption and our usual goal in restoration beg the question of what we mean by degraded, desirable and improvement. Furthermore, how do we decide when an ecosystem is so degraded or damaged that it is in need of restoration? What sort of values are we bringing to the process when we talk about restoration? What are we really doing when we restore an ecosystem? In this talk, I will concentrate on how we decide the final state that is the goal of our restoration efforts and what it means when we describe restorations using terms like natural and artificial. I will argue that by using terms like natural and artificial we are setting up a false dichotomy that separates us from the act of restoration and from a very important part of restoration – restoring the human relationship to the rest of the biota. Ideally restoration is an activity that can be engaged by almost all people working at small to large scales. We should do all we can to bridge that gulf and make restoration as appealing as possible to potential restorationists.
A series of experimental disturbances by sediment deposition were conducted in the salt marsh at ... more A series of experimental disturbances by sediment deposition were conducted in the salt marsh at Bolinas Lagoon to examine the ability of marsh plants to recover from small‐scale anthropogenic disturbances. Results from these experiments demonstrated that species differ in their ability to recover, with Distichlis spicata and Salicornia virginica recovering most quickly from disturbances that occurred at any time of the year. Other species, such as Frankenia grandifolia and Jaumea carnosa, only recovered from disturbances that occurred early in the growing season. Recovery was by vegetative ingrowth of plants surrounding a disturbed patch or by growth of buried plants up through the sediment. Seedling establishment was rare and did not significantly influence recovery. Anthropogenic disturbances such as excessive sedimentation may cause lasting changes by eliminating or reducing the cover of species sensitive to sediment deposition, and by changing the substrate so that recruitment from seeds is limited.
R estoration ecology had its genesis in the 1930s as Midwestern ecologists came to the realizatio... more R estoration ecology had its genesis in the 1930s as Midwestern ecologists came to the realization that nearly all the tallgrass prairie in Illinois, Iowa, and Wisconsin had been converted to agricultural or urban land uses (Curtis and Greene 1949, Critical Trends Assessment Project 1994, Smith 1998). While calls for preservation of remaining prairie in Iowa began by 1919 (Smith 1998), the pioneer restoration ecologists of the early 20th century recognized that if extensive areas of tallgrass prairie were going to be part of our future, they would have to begin to restore these historic grasslands. The first efforts were undertaken at the University of Wisconsin-Madison Arboretum, initially as experimental plots under the direction of biology professor Dr. Norman Passett, and later under the direction of Dr. Theodore Sperry and Dr. Henry Greene, Dr. Sperry led the restoration activity at Curtis Prairie-a planting effort that involved men from the Civilian Conservation Corps and lasted from 1936 through 1940-while Dr. Greene almost single-handedly planted Greene Prairie between 1943 and 1952 (Blewett and Cottam 1984). Their efforts served as the inspiration for the third tallgrass prairie restoration in the Midwest (Howell and Jordan, 1991) which took place at the Knox College Green Oaks Field Study Center in west-central Illinois.
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