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society for ecological restoration intern a t i o n a l The SER International Primer o n Ecological Restoration Society for Ecological Restoration International Science & Policy Working Group (Version 2: October, 2004)* Section 1: Overview ...... 1 Section 2: Definition of Ecological Restoration ...... 3 Section 3: Attributes of Restored ...... 3 Section 4: Explanations of Terms ...... 4 Section 5: Reference Ecosystems ...... 8 Section 6: Exotic Species ...... 9 Section 7: Monitoring and Evaluation ...... 10 Section 8: Restoration Planning...... 11 Section 9: Relationship Between Restoration Practice and Restoration ...... 11 Section 10: Relationship of Restoration to Other Activities ...... 12 Section 11: Integration of Ecological Restoration into a Larger Program. . 13

This document should be cited as: Society for Ecological Restoration International Science & Policy Working Group. 2004. The SER International Primer on Ecological Restoration. www.ser.org & Tucson: Society for Ecological Restoration International. The principal authors of this Primer were André Clewell (Quincy, FL USA), James Aronson (Montpellier, France), and Keith Winterhalder (Sudbury, ON Canada). Clewell initially proposed the Primer and wrote its first draft. Aronson and Winterhalder, in collaboration with Clewell, revised the Primer into its present form. Winterhalder, in his capacity as Chairperson of SER’s Science & Policy Working Group, coordinated this effort and invited other Working Group members to participate. Eric Higgs (Victoria, BC Canada) crafted the Overview sec- tion. Dennis Martinez (Douglas , CA USA) contributed a position paper that became the basis for text pertaining to cultural ecosystems. Other Working Group members provided critiques and suggestions as the work progressed, including Richard Hobbs (Murdoch, WA ), James Harris (London, UK), Carolina Murcia (Cali, Colombia), and John Rieger (San Diego, CA USA). The SPWG acknowledges Eric Higgs, former Chairperson of SER International’s Board of Directors, for his encouragement and for bringing the Primer before SER International’s Directors for its official adoption as an SER International document on 6 April, 2002, by unanimous vote. This document supercedes SER Int e r n a t i o n a l ’s Project Policies that wer e initially published in Res t o r ation Eco l o g y 2(2):132-133, 1994, and that wer e later posted on SER Int e r n a t i o n a l ’s website. This document also supercedes the policy on Project Evaluation that was posted on the SER International website. SER International environmental policies, initially published in 1(3):206-207, 1993, remain in effect. *The content of the second version is exactly the same as the first version published in 2002, except that International has been appended to SER's name, photos have been added, and the graphics red e s i g n e d . Version 2 was published simultaneously in print and on the internet at ww w. s e r. o r g . Section 1: Overview cological restoration is an intentional activity Restoration represents an indefinitely long-term Ethat initiates or accelerates the recovery of an commitment of land and resources, and a proposal with respect to its health, integrity and to restore an ecosystem requires thoughtful delibera- sustainability. Frequently, the ecosystem that requires tion. Collective decisions are more likely to be hon- restoration has been degraded, damaged, trans- ored and implemented than are those that are made formed or entirely destroyed as the direct or indirect unilaterally. For that reason, it behooves all stake- result of human activities. In some cases, these holders to arrive at the decision to initiate a restora- impacts to ecosystems have been caused or aggravat- tion project by consensus. Once the decision to ed by natural agencies such as , , restore is made, the project requires careful and sys- , or volcanic eruption, to the point at which tematic planning and a monitored approach towards the ecosystem cannot recover its predisturbance state ecosystem recovery. The need for planning intensifies or its historic developmental trajectory. when the unit of restoration is a complex land- scape of contiguous ecosystems. Restoration attempts to return an ecosystem to its historic trajec- Interventions employed in t o ry. Historic conditions are restoration vary widely t h e re f o re the ideal start i n g among projects, depending point for re s t o r a t i o n on the extent and dura- design. The re s t o re d tion of past disturbances, ecosystem will not nec- cultural conditions that essarily re c over its for- have shaped the land- mer state, since contem- scape, and contemporary p o r a ry constraints and constraints and opportu- conditions may cause it nities. In the simplest cir- to develop along an cumstances, restoration a l t e red trajectory. The his- consists of removing or modifying a specific distur- toric trajectory of a seve re l y bance, thereby allowing ecolog- impacted ecosystem may be dif- ical processes to bring about an ficult or impossible to determine independent recovery. For example, with accuracy. Ne ve rtheless, the general removing a dam allows the return of an d i rection and boundaries of that trajectory can historical flooding regime. In more complex circum- be established through a combination of know l e d g e stances, restoration may also require the deliberate of the damaged ecosystem’s pre-existing stru c t u re , reintroduction of that have been lost, composition and functioning, studies on compara- and the elimination or control of harmful, invasive ble intact ecosystems, information about re g i o n a l exotic species to the greatest practicable extent. e n v i ronmental conditions, and analysis of other Often, ecosystem degradation or transformation has ecological, cultural and historical re f e rence infor- multiple, protracted sources, and the historical con- mation. These combined sources allow the historic stituents of an ecosystem are substantially lost. t r a j e c t o ry or re f e rence conditions to be chart e d Sometimes the developmental trajectory of a degrad- f rom baseline ecological data and pre d i c t i ve mod- ed ecosystem is blocked altogether, and its recovery els, and its emulation in the restoration pro c e s s through natural processes appears to be delayed should aid in piloting the ecosystem tow a rd s indefinitely. In all of these cases, however, ecological i m p roved health and integrity. restoration aims to initiate or facilitate the resump- www.ser.org SER International Primer on Ecological Restoration 1 tion of those processes which will return the ecosys- accept and even encourage new culturally appropri- tem to its intended trajectory. ate and sustainable practices that take into account contemporary conditions and constraints. In this When the desired trajectory is realized, the ecosys- regard, the North American focus on restoring pris- tem under manipulation may no longer require tine landscapes makes little or no sense in places like external assistance to ensure its future health and Europe where cultural landscapes are the norm, or in integrity, in which case restoration can be considered large parts of Africa, Asia and Latin America, where complete. Nevertheless, the restored ecosystem often ecological restoration is untenable unless it manifest- requires continuing management to counteract the ly bolsters the ecological base for human survival. invasion of opportunist species, the impacts of vari- ous human activities, change, and other What makes ecological restoration especially inspir- unforeseeable events. In this respect, a restored ing is that cultural practices and ecological processes ecosystem is no different from an undamaged can be mutually reinforcing. Accordingly, it is not ecosystem of the same kind, and both are likely to surprising that interest in ecological restoration is require some level of . growing rapidly worldwide and that, in most cases, Although ecosystem restoration and ecosys- cultural beliefs and practices are drawn upon tem management form a continuum to help determine and shape of what is and often employ similar sorts of to be performed under the rubric intervention, ecological restora- of restoration. tion aims at assisting or initi- ating recovery, whereas The definition presented on ecosystem management is the next page, the one offi- intended to guarantee the cially endorsed by the continued well-being of Society for Eco l o g i c a l the restored ecosystem Restoration Int e r n a t i o n a l , thereafter. is sufficiently general to al l o w a wide variety of Some ecosystems, partic- ap p r oaches to res t o r a t i o n , ularly in developing coun- while giving prominence to tries, are still managed by the historically rich idea of traditional, sustainable cultur- “rec o ver y.” T al practices. Reciprocity exists in these cultural ecosystems between cultural activities and ecological processes, such that human actions reinforce ecosystem health and sustainability. Many cultural ecosystems have suffered from demographic growth and external pressures of various kinds, and are in need of restoration. The restoration of such ecosys- tems normally includes the concomitant recovery of indigenous ecological management practices, includ- ing support for the cultural survival of and their languages as living libraries of tra- ditional ecological knowledge. Ecological restoration encourages and may indeed be dependent upon long-term participation of local people. Cultural conditions in traditional cultures are currently undergoing unprecedented global change. To accom- modate this change, ecological restoration may

2 SER International Primer on Ecological Restoration www.ser.org Section 2: 1. The restored ecosystem contains a characteristic assemblage of the species that occur in the refer- efinition of ence ecosystem and that provide appropriate D Ecological structure. 2 . The re s t o red ecosystem consists of indigenous species to the greatest practicable extent. In Restoration re s t o red cultural ecosystems, allowances can be made for exotic domesticated species and cological restoration is the process of assisting for non-inva s i ve ruderal and segetal species Ethe recovery of an ecosystem that has been that presumably co-evo l ved with them. degraded, damaged, or destroyed. T Ruderals are that colonize disturbed sites, whereas segetals typically grow inter- m i xed with crop species.

Section 3: 3. All functional groups necessary for the contin- ued development and/or stability of the restored ttributes of ecosystem are represented or, if they are not, the A missing groups have the potential to colonize by Restored natural means. 4. The physical environment of the restored Ecosystems ecosystem is capable of sustaining reproducing populations of the species necessary for its con- his section addresses the question of what is tinued stability or development along the Tmeant by “recovery” in ecological restoration. desired trajectory. An ecosystem has recovered - and is restored - when it contains sufficient biotic and abiotic resources to 5. The restored ecosystem apparently functions continue its development without further assistance normally for its ecological stage of development, or subsidy. It will sustain itself structurally and func- and signs of dysfunction are absent. tionally. It will demonstrate resilience to normal ranges of environmental stress and . It will interact with contiguous ecosystems in terms of 6. The restored ecosystem is suitably integrated biotic and abiotic flows and cultural interactions. into a larger ecological matrix or landscape, with which it interacts through abiotic and The nine attributes listed below provide a basis for biotic flows and exchanges. determining when restoration has been accom- plished. The full expression of all of these attributes 7. Potential threats to the health and integrity of is not essential to demonstrate restoration. Instead, it the restored ecosystem from the surrounding is only necessary for these attributes to demonstrate landscape have been eliminated or reduced as an appropriate trajectory of ecosystem development much as possible. towards the intended goals or reference. Some attrib- utes are readily measured. Others must be assessed indirectly, including most ecosystem functions, 8. The restored ecosystem is sufficiently resilient to which cannot be ascertained without research efforts endure the normal periodic stress events in the that exceed the capabilities and budgets of most local environment that serve to maintain the restoration projects. integrity of the ecosystem. www.ser.org SER International Primer on Ecological Restoration 3 Section 4: 9. The restored ecosystem is self-sustaining to the same degree as its reference ecosystem, and has xplanations the potential to persist indefinitely under exist- E ing environmental conditions. Nevertheless, aspects of its , structure and func- of Terms tioning may change as part of normal ecosystem development, and may fluctuate in response to arious technical terms are introduced through- normal periodic stress and occasional distur- Vout this document. Some of these terms may bance events of greater consequence. As in any be unfamiliar to readers who are not ecologists, intact ecosystem, the species composition and while others have multiple connotations from differ- other attributes of a restored ecosystem may ential usage. To reduce the potential for misunder- evolve as environmental conditions change. standings, key terms are explained in the manner in which they are used in this document. Other attributes gain relevance and should be added to this list if they are identified as goals of the An ecosystem consists of the biota (plants, restoration project. For example, one of animals, ) within a the goals of restoration might be to given area, the environment that provide specified natural goods sustains it, and their interac- and services for social benefit tions. Populations of species in a sustainable manner. In that comprise the biota are this respect, the restored collectively identified as ecosystem serves as natu- the biotic community. ral capital for the accrual This community is fre- of these goods and serv- quently segregated on the ices. Another goal might basis of taxonomic status be for the restored (e.g., the commu- ecosystem to provide nity) or life form (e.g., for rare species or the tree community). to harbor a diverse Assemblages of organisms genepool for selected can also be recognized by species. Other possible goals their functional roles in the of restoration might include the ecosystem (e.g. primary producers, provision of aesthetic amenities or , , , the accommodation of activities of social nitrogen fixers, pollinators), in which case consequence, such as the strengthening of a commu- they are known as functional groups. The physical nity through the participation of individuals in a or abiotic environment that sustains the biota of an restoration project. T ecosystem includes the or substrate, the atmos- pheric or aqueous medium, hydrology, weather and climate, topographic relief and aspect, the nutrient regime, and the salinity regime. Habitat refers to the dwelling place of an organism or community that provides the requisite conditions for its life processes.

An ecosystem can be recognized in a spatial unit of any size, from a microsite containing only a few individuals to an area showing some degree of struc- tural and taxonomic homogeneity such as a small- scale and community-based “ ecosystem,” or

4 SER International Primer on Ecological Restoration www.ser.org a large-scale and biome-based “tropical rainforest fies as ecological restoration. Sustainable cultural ecosystem.” Ecological restoration can be conducted practices are traditional human land uses that main- at a wide variety of scales, but in practice all ecosys- tain biodiversity and . In this context, tem restoration should be approached with a spatial- the biota is valued as much for its importance to ly explicit landscape perspective, in order to ensure ecosystem stability as it is for its shortterm worth as the suitability of flows, interactions and exchanges commodities. Perhaps all natural ecosystems are cul- with contiguous ecosystems. A landscape consists of turally influenced in at least some small manner, and a mosaic of two or more ecosystems that exchange this reality merits acknowledgement in the conduct organisms, energy, water and nutrients. A legitimate of restoration. and indeed important object of much ecological restoration is the reintegration of fragmented ecosys- The terms degradation, damage, destruction and tems and landscapes, rather than focusing on just a transformation all rep r esent deviations from the nor- single ecosystem. mal or desired state of an intact ecosystem. The mean- ings of these terms over l a p , and their application is A or ecosystem is one that devel- not always clear. Deg r a d a t i o n pe r tains to subtle or oped by natural processes and that is self- gradual changes that reduce ecological integrity organizing and self-maintaining. A and health. Dam a g e refers to acute and cultural landscape or ecosystem ob vious changes in an ecosystem. is one that has developed An ecosystem is de s t r oyed wh e n under the joint influence of degradation or damage natural processes and rem o ves all macroscopic life, human-imposed organiza- and commonly ruins the tion. Many physical environment as and savannas are main- well. Tra n s f o rm a t i o n is tained in large part by the conversion of an the human activities ecosystem to a differen t such as the regular igni- kind of ecosystem or land tion of surface for use type. hunting, gathering or ani- mal husbandry. In Europe, A reference ecosystem can many of the species-rich serve as the model for plan- meadows are cultural ecosys- ning an ecological restoration tems that arose following forest project, and later serve in the evalu- removal in the Bronze Age, and have ation of that project. In instances where been maintained through mowing and seasonal the object of restoration consists of two or by livestock. The repair of a damaged mead- more kinds of ecosystems, the reference can be called ow qualifies as ecological restoration, even though the reference landscape or, if only a portion of a the meadow ecosystem that is selected as the land- local landscape is to be restored, the reference land- scape of reference derives from human activities. In scape unit. The designated ecosystem, landscape or another example, a dense coniferous forest currently unit can simply be called the reference.Typically, occupies large parts of western North America. In the reference represents a point of advanced develop- the 19th century, much of this forest was open and ment that lies somewhere along the intended trajec- park-like with copious herbaceous cover, owing to tory of the restoration. In other words, the restored the frequent use of and species utilization ecosystem is eventually expected to emulate the by indigenous tribal people. This woodland seemed attributes of the reference, and project goals and natural and its condition was sustainable under the strategies are developed in light of that expectation. regime of tribal land usage. The return of this The reference can consist of one or several specified ecosystem to an open, park-like woodland, occupied locations that contain model ecosystems, a written and utilized in the traditional tribal manner, quali- description, or a combination of both. Information www.ser.org SER International Primer on Ecological Restoration 5 collected on the reference includes both biotic and species present, and , i.e. the number abiotic components. A more comprehensive discus- of different species present. The importance of an sion of the reference ecosystem appears in Section 5. ample recovery in species composition cannot be overstated in restoration. All functional species- An ecological trajectory is one that describes the groups must be represented if a restored ecosystem is developmental pathway of an ecosystem through to maintain itself. Species redundancy, i.e. the pres- time. In restoration, the trajectory begins with the ence of multiple species that play similar roles in unrestored ecosystem and progresses towards the ecosystem dynamics, provides assurance that ecosys- desired state of recovery that is expressed in the goals tem health is maintained in response to stress, dis- of a restoration project and embodied in the refer- turbance or other environmental changes. ence ecosystem. The trajectory embraces all ecologi- cal attributes - biotic and abiotic - of an ecosystem, In order for an ecosystem to be well adapted to local and in theory can be monitored by the sequential site conditions and to display resilience in response measurement of coherent suites of ecological param- to a stressful or changing environment, the species- eters. Any given trajectory is not narrow and specif- populations that comprise it must possess genetic ic. Instead, a trajectory embraces a broad yet fitness. An ecosystem containing genetically confined range of potential ecological fit populations is one that is not only expressions through time, as adapted to the current environmen- might be described mathemat- tal regime, but possesses some ically by chaos theory, or “genetic redundancy”, whereby predicted by various eco- the gene pool contains a logical models. A fully diversity of alleles that may empirical description of be selected in response to a trajectory is impeded environmental change. in two ways. First, the Under normal circum- number of ecosystem stances, the reintroduction traits that can be meas- of local is suffi- ured far exceeds those cient to maintain genetic that can be reasonably fitness. Nevertheless, in monitored, and the sites that have suffered sub- description of the trajectory stantial damage and conse- over time is necessarily incom- quent alteration to their physical plete. Second, the monitoring environment, the introduction of data lend themselves to the plotting diverse genetic stock may be the pre- of trajectories for individual parameters, but ferred strategy, thereby allowing recombina- their combination into a single trajectory represent- tion and the eventual development of novel, more ing the entire ecosystem requires highly complex adaptive ecotypes. multivariate analysis of a kind that has yet to be developed. This represents a critical research chal- By community structure is meant the physiognomy lenge for the future. or architecture of the community with respect to the density, horizontal stratification, and frequency dis- Biodiversity refers to biota in terms of taxonomic tribution of species-populations, and the sizes and and genetic diversity, the variety of life forms present life forms of the organisms that comprise those com- and the community structure thereby created, and munities. the ecological roles performed. The biota is organ- ized hierarchically from the level of the genome up Ecological processes or ecosystem functions are to individual organisms, species, populations, and the dynamic attributes of ecosystems, including communities. Two related aspects of biodiversity are interactions among organisms and interactions species composition, i.e. the taxonomic array of between organisms and their environment.

6 SER International Primer on Ecological Restoration www.ser.org Ecological processes are the basis for self-mainte- used interchangeably for “stressor” or “stress event”. nance in an ecosystem. Some restoration ecologists However, the term “disturbance” is restricted herein limit the use of the term “ecosystem functions” to to impacts on ecosystems that are more severe or those dynamic attributes which most directly affect acute than normal stress events. metabolism, principally the sequestering and trans- formation of energy, nutrients, and moisture. is the term describing an ecosystem’s abil- Examples are carbon fixation by , ity to maintain its structural and functional attrib- trophic interactions, , and mineral utes in the face of stress and disturbances. Resilience nutrient cycling. When ecosystem functions are is the ability of an ecosystem to regain structural and strictly defined in this manner, other dynamic attrib- functional attributes that have suffered harm from utes are distinguished as “ecosystem processes” such stress or disturbance. Ecosystem stability is the abil- as substrate stabilization, microclimatic control, dif- ity of an ecosystem to maintain its given trajectory ferentiation of habitat for specialized species, pollina- in spite of stress; it denotes dynamic equilibrium tion and . Functioning at larger spatial rather than stasis. Stability is achieved in part on the scales is generally conceived in more general terms, basis of an ecosystem’s capacity for resistance and such as the long-term retention of nutrients and resilience. moisture and overall ecosystem sustainability. The terms ecosystem integrity and ecosystem health Ecosystem functions and processes, along with the are commonly used to describe the desired state of a reproduction and growth of organisms, are what restored ecosystem. Although some authors use the cause an ecosystem to be self-renewing or autogenic. terms interchangeably, they are distinct in meaning. A common goal for the restoration of any natural Ecosystem integrity is the state or condition of an ecosystem is to recover autogenic processes to the ecosystem that displays the biodiversity characteristic point where assistance from restorationists is no of the reference, such as species composition and longer needed. In this regard, the central role of a community structure, and is fully capable of sustain- restoration practitioner is to initiate autogenic ing normal ecosystem functioning. processes. Restoration practitioners commonly assume that autogenic processes will commence once Ecosystem health is the state or condition of an the appropriate species composition and structure ecosystem in which its dynamic attributes are have been re-established. This is not always a valid expressed within ‘normal’ranges of activity relative to assumption, but it is a reasonable starting point for its ecological stage of development. A restored ecosystem restoration. ecosystem expresses health if it functions normally relative to its reference ecosystem, or to an appropri- Some dynamic processes are external in origin, such ate set of restored ecosystem attributes such as those as fires, floods, damaging wind, salinity shock from that are listed above in Section 3. A state of ecosys- incoming tides and storms, freezes, and droughts. tem integrity suggests, but does not necessarily con- These external processes stress the biota and are firm, a concurrent state of ecosystem health and a sometimes designated as stressors. The biota of any suitable abiotic environment. T given ecosystem must be resistant or resilient to the normal stress events that periodically occur in the local environment. These events serve to maintain ecosystem integrity, by preventing the establishment of other species that are not adapted to those stress conditions. For example, the tidal influx of saline water is essential to maintain a salt marsh ecosystem and prevent its conversion to a . In cultural ecosystems, human-mediated activities such as burning or grazing qualify as stressors. The terms disturbance or perturbation are sometimes www.ser.org SER International Primer on Ecological Restoration 7 Section 5: tographs; remnants of the site to be restored, indi- eference cating previous physical conditions and biota; R ■ remnants of the site to be restored, indicating pre- Ecosystems vious physical conditions and biota; ■ ecological descriptions and species lists of similar reference ecosystem or reference serves as a intact ecosystems; Amodel for planning a restoration project, and later for its evaluation. In its simplest form, the ref- ■ herbarium and museum specimens; erence is an actual site, its written description, or both. The problem with a simple reference is that it ■ represents a single state or expression of ecosystem historical accounts and oral histories by persons attributes. The reference that is selected could have familiar with the project site prior to damage; been manifested as any one of many potential states that fall within the historic range of variation ■ paleoecological evidence, e.g. fossil pollen, of that ecosystem. The reference charcoal, tree ring history, rodent mid- reflects a particular combination of dens. stochastic events that occurred during ecosystem develop- The value of the ref e re n c e ment. in c r eases with the amount of information it contains, In the same manner, an but ever y inven t o r y is ecosystem that undergoes co m p r omised by limita- restoration can develop tions of time and fund- into any of a potentially ing. Min i m a l l y , a baseline large array of states. Any ecological inven t o r y state that is expressed is describes the salient attrib- acceptable as restoration, utes of the abiotic environ - as long as it is comparable ment and important aspects to any of the potential states of biodiversity such as species into which its reference could composition and community have developed. Thus, a simple ref- st ru c t u r e. In addition, it identifies erence inadequately expresses the con- the normal periodic stress events that stellation of potential states and the historic range of maintain ecosystem integrity. Descriptions of variation expressed by the restored ecosystem. the ref e r ence for cultural ecosystems should identify Therefore, a reference is best assembled from multi- the cultural practices that are critical in restoring and ple reference sites and, if necessary, other sources. later in managing that ecosystem. This composite description gives a more realistic basis for restoration planning. The description of a reference is complicated by two factors that should be reconciled to assure its quality Sources of information that can be used in describ- and usefulness. First, a reference site is normally ing the reference include: selected for its well-developed expression of biodiver- sity, whereas a site in the process of restoration typi- cally exhibits an earlier ecological stage. In such a ■ ecological descriptions, species lists and maps of case, the reference requires interpolation back to a the project site prior to damage; prior developmental phase for purposes of both proj- ect planning and evaluation. The need for interpre- ■ historical and recent aerial and ground-level pho- tation diminishes where the developmental stage at

8 SER International Primer on Ecological Restoration www.ser.org the restoration project site is sufficiently advanced Section 6: for direct comparison with the reference. Second, where the goal of restoration is a natural ecosystem, xotic Species nearly all available references will have suffered some E adverse human-mediated impacts that should not be emulated. Therefore, the reference may require inter- n exotic species of plant or animal is one that pretation to remove these sources of artifice. For Awas introduced into an area where it did not these reasons, the preparation of the description of previously occur through relatively recent human the reference requires experience and sophisticated activities. Since ecological restoration of natural ecological judgement. ecosystems attempts to recover as much historical authenticity as can be reasonably accommodated, the reduction or elimination of exotic species at restora- Written restoration project goals are critical for tion project sites is highly desirable. Nonetheless, determining the detail that is needed in the descrip- financial and logistical constraints often exist, and it tion of the reference. For large, landscape-scale is important to be realistic and pragmatic in restoration for which only general goals are pre- approaching exotic species control. In cultural land- scribed, the description of the reference can scapes, exotic species are frequently an be equally general. In such instances, integral part of the ecosystem, partic- aerial photographs may represent ularly as crops and livestock, and the most important source of even as ruderals or segetals that information for the prepara- have presumably co-evolved tion of the reference. with these domesticated Restoration at a finer species. Such exotic species scale may require much are acceptable for cultural more detailed reference restoration. information, such as data that are collected on-site in small plots. In natural ecosystems, T invasive exotic species commonly compete with and replace native species. However, not all exotic species are harmful. Indeed, some even fulfill ecological roles formerly played by the native species that have become rare or extirpated. In such instances, the rationale for their removal may be tenuous. Some exotic species were introduced centuries ago by human or non-human agents and have become naturalized, so that their status as an exotic is debatable. Other species have migrated in and out of the region in response to climatic fluctua- tions during the Holocene, and can scarcely be regarded as exotics. Even if all exotic species are removed from a restoration site, the opportunity for reinvasion may remain high. Therefore it becomes essential for a policy to be developed for each exotic species present, based upon biological, economic and logistical realities. Highest priority is best reserved for the control or extirpation of those species which

www.ser.org SER International Primer on Ecological Restoration 9 pose the greatest threats. These include invasive ance Standards, also known as design criteria or plant species that are particularly mobile and pose an success criteria. These standards or criteria are con- ecological threat at landscape and regional levels, and ceived in large part from an understanding of the animals that consume or displace native species. reference ecosystem. Performance standards provide Care should be taken to cause the least possible dis- an empirical basis for determining whether or not turbance to indigenous species and as exotics project objectives have been attained. Objectives, are removed. performance standards, and protocols for monitoring and for data assessment should be incorporated into In some instances, non-indigenous plants are used restoration plans prior to the start of a project. If for a specific purpose in the restoration project, for interpretation of the data collected during monitor- example as cover crops, nurse crops or nitrogen fix- ing shows that performance standards have been ers. Unless these are relatively short-lived, non-per- met, there can be no doubt that project objectives sistent species that will be replaced in the course of were achieved, and the restored ecosystem is likely to succession, their eventual removal should be includ- be sufficiently resilient to require little or no further ed in restoration plans. T assistance from the restoration practitioner.

Section 7: It is assumed that project goals are, or soon will be, fulfilled once the objectives are attained. The validity onitoring and of this assumption is not guaranteed, since the M objectives and performance standards that were des- ignated may prove to be inadequate, and unantici- Evaluation pated environmental vicissitudes can deflect the restoration trajectory. For that reason, and since properly planned restoration project attempts goals are ideals that resist strict empirical measure- Ato fulfill clearly stated goals that reflect impor- ment, an element of professional judgment and sub- tant attributes of the reference ecosystem. Goals are jectivity is inevitable in the evaluation of goals. attained by pursuing specific objectives. The goals are ideals, and the objectives are concrete measures Three strategies exist for conducting an evaluation: taken to attain these goals. Two fundamental ques- direct comparison, attribute analysis and trajectory tions should be asked with respect to the evaluation analysis. In direct comparison, selected parameters of a restored ecosystem. Were the objectives accom- are determined or measured in the reference and plished? Were the goals fulfilled? Answers to both restoration sites. If the reference description is thor- questions gain validity only if the goals and objec- ough, as many as 20 or 30 parameters can be com- tives were stated prior to implementation of restora- pared that include aspects of both the biota and the tion project work. abiotic environment. This can lead to ambiguity of interpretation when the results of some comparisons Ecosystems are complex, and no two intact ecosys- are close and others are not. The question arises - tems are ever identical, at least not when examined how many parameters must have similar values and in fine resolution. For that reason, no restored how close must the values be before restoration goals ecosystem at a project site can ever be identical to are satisfied? The most satisfactory approach may be any single reference. The number of ecosystem vari- to carefully select a coherent suite of traits that col- ables that can be used in an evaluation is too great lectively describe an ecosystem fully yet succinctly. for all to be measured within a reasonable period of time. The selection of which variables to assess and In attribute analysis, attributes are assessed in rela- which to ignore requires pragmatism and value judg- tion to the list provided in Section 3. In this strategy, ment by the evaluator. quantitative and semi-quantitative data from sched- uled monitoring and other inventories are useful in Objectives are evaluated on the basis of perform- judging the degree to which each goal has been achieved.

10 SER International Primer on Ecological Restoration www.ser.org Tra j e c t o r y analysis is a promising strategy, still ■ well-developed and explicitly stated performance under development, for interpreting large sets of standards, with monitoring protocols by which co m p a r a t i v e data. In this strategy, data collected peri- the project can be evaluated; odically at the restoration site are plotted to establish tr ends. Trends that lead towa r ds the ref e r ence condi- ■ strategies for long-term protection and mainte- tion confirm that the restoration is following its nance of the restored ecosystem. intended trajectory. Where feasible, at least one untreated control plot Evaluations include the assessment of any stated goals should be included at the project site, for purposes and objectives that pertain to cultural, economic and of comparison with the restored ecosystem. T other societal concerns. For these, the techniques of ev aluation may include those of the social sciences. The evaluation of socio-economic goals is importa n t to stakeholders and ultimately to policy-makers who Section 9: decide whether or not to authorize and finance restoration projects. T elationship Section 8: RBetween Restoration Restoration Planning Practice and lans for restoration projects include, at a mini- Pmum, the following: Restoration ■ a clear rationale as to why restoration is needed; an ecological description of the site designated for Ecology restoration; cological res t o r a t i o n is the practice of res t o r i n g ■ an ecological description of the site designated for Eecosystems as performed by practitioners at spe- restoration; cific project sites, whereas restoration ecology is the science upon which the practice is based. Res t o r a t i o n ■ a statement of the goals and objectives of the ec o l o g y ideally provides clear concepts, models, restoration project; methodologies and tools for practitioners in support of their practice. Sometimes the practitioner and the ■ restoration ecologist are the same person-the nexus of a designation and description of the reference; practice and theory. The field of restoration ecology is not limited to the direct service of restoration practice. ■ an explanation of how the proposed restoration Restoration ecologists can advance ecological theory will integrate with the landscape and its flows of by using restoration project sites as experimental area s . organisms and materials; For example, information derived from project sites could be useful in resolving questions pertaining to ■ explicit plans, schedules and budgets for site of biotic communities. Furt h e r , preparation, installation and post-installation res t o r ed ecosystems can serve as ref e r ences for set- activities, including a strategy for making prompt aside areas designated for . T mid-course corrections;

www.ser.org SER International Primer on Ecological Restoration 11 Reclamation projects that are more ecologically Section 10: based can qualify as rehabilitation or even restora- elationship of tion. R Mitigation is an action that is intended to compen- Restoration sate environmental damage. Mitigation is commonly required in the USA as a condition for the issuance to Other of permits for private development and public works projects that cause damage to . Some, but perhaps relatively few, mitigation projects satisfy the Activities attributes of restored ecosystems listed in Section 3, and thus qualify as restoration. cological restoration is one of several activities Ethat strive to alter the biota and physical condi- The term creation has enjoyed recent usage, particu- tions at a site, and are frequently confused with larly with respect to projects that are conducted as restoration. These activities include reclamation, mitigation on terrain that is entirely devoid of vege- rehabilitation, mitigation, and tation. The alternate term fabrication is sometimes various kinds of management, including employed. Frequently, the process of voiding a site wildlife, fisheries and range management, agro- causes sufficient change in the environment to forestry, and forestry. All of these activities can over- require the installation of a different kind of ecosys- lap with and may even qualify as ecological restora- tem from that which occurred historically. Creation tion if they satisfy all criteria expressed in Section 3 that is conducted as supervised engineering or land- of this document. Relative to other kinds of activi- scape architecture cannot qualify as restoration ties, restoration generally requires more postinstalla- because restoration initiates ecosystem development tion aftercare to satisfy all these criteria. along a preferred trajectory, and thereafter allows autogenic processes to guide subsequent develop- Rehabilitation shares with restoration a fundamen- ment with little or no human interference. tal focus on historical or pre-existing ecosystems as models or references, but the two activities differ in Ecological engineering involves manipulation of their goals and strategies. Rehabilitation emphasizes natural materials, living organisms and the physical- the reparation of ecosystem processes, productivity chemical environment to achieve specific human and services, whereas the goals of restoration also goals and solve technical problems. It thus differs include the re-establishment of the pre-existing biot- from civil engineering, which relies on human-made ic integrity in terms of species composition and materials such as steel and concrete. Predictability is community structure. Nonetheless, restoration, as a primary consideration in all engineering design, broadly conceived herein, probably encompasses a whereas restoration recognizes and accepts unpre- large majority of project work that has previously dictable development and addresses goals that reach been identified as rehabilitation. beyond strict pragmatism and encompass biodiversi- ty and ecosystem integrity and health. When pre- The term reclamation, as commonly used in the dictability is not at issue, the scope of many ecologi- context of mined lands in North America and the cal engineering projects could be expanded until UK, has an even broader application than rehabilita- they qualify as restoration. T tion. The main objectives of reclamation include the stabilization of the terrain, assurance of public safety, aesthetic improvement, and usually a return of the land to what, within the regional context, is consid- ered to be a useful purpose. , which is normally a component of land reclamation, may entail the establishment of only one or few species.

12 SER International Primer on Ecological Restoration www.ser.org Section 11: ntegration of I Ecological Restoration into a Larger Program

cological restoration is sometimes only one of Emany elements within a larger public or private sector enterprise, such as development projects and programs for watershed management, ecosystem management and nature conservation. Project man- agers of these larger undertakings should be aware of the complexities and costs involved in planning and implementing ecological restoration. Cost savings can be realized by careful coordination of restoration activities with other aspects of a large program. For this reason, project managers will benefit by recog- nizing ecological restoration as an integral compo- nent of a program. If this is done, the restorationist can contribute substantively to all aspects of the pro- gram that impinge on restoration. Moreover, the restorationist will be in a position to ensure that all ecological restoration is well conceived and fully real- ized. In this manner, the public good is served. T

www.ser.org SER International Primer on Ecological Restoration 13 Our mission is to promote ecological restoration as a means of sustaining the diversity of life on and reestablishing an ecologically healthy relationship between nature and culture.

SER International is a non-profit organization infused with the energy of involved members — individuals and organizations — who are actively engaged in ecologically sensitive repair and management of ecosystems.

Our members live and work all over the planet and draw on an unprecedented breadth of experience, knowledge sets and cultural perspectives. We are scientists, planners, administrators, ecological consultants, First Peoples, landscape architects, philosophers, teachers, engineers, natural areas managers, writers, growers, community activists, and volunteers.

SER International serves the growing field of ecological restoration by facilitating dialogue among restorationists; encouraging research; promoting awareness of, and public support for, restoration and restorative management; contributing to public policy discussions; recognizing those who have made outstanding contributions to the field of restoration; and promoting ecological restoration around the globe.

Founded in 1987, SER International now has members in 37 countries, with 14 chapters worldwide. Recognized by public and private organizations as the source for expertise on restoration science, practice and pol- icy, SER International achieves its objectives through cooperation with partner organizations and the work of its global membership.

We're a growing world community of practitioners dedicated to restoring damaged and disturbed ecosystems ... shouldn't you be a member of SER International? You can join online by visiting www.ser.org or call, write, email or fax us for a membership application.

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