,3
48
Reganold1991;Felleman1992;Jenn et al.1993; Olshansky1996).
The primary reasons for lack of attention to bio-diversity conrvation planning by local governments include:lack of perceived mandate(Jenn et al.1993; Press et al.1996),more immediate cris occupying their attention(Davis,),lack of political will(Press et al.1996;Tarlock1993),lack of funding (Simmens1996),and lack of data,tools,methods,and experti(Press et al.1996;Jennings and Reganold 1991;Felleman1992;Jenn et al.1993).Here we focus on addressing the lack of tools,methods,and experti that can impede a local government’s abil-ity to include biodiversity in the land-u permitting decision process.
Planning is an integrativefield–it collects infor-mation from a broad range of disciplines and synthe-sizes that information with community objectives into a plan to guide future land u(Lynch1962;McHarg 1969;Steiner1991).The breadth,amount,and com-plexity of the information that must be synthesized can be staggering(Scarlett1997;Zhu et al.1998;Sim-mens1996).Thus,planners require highly simplified information from the various disciplines;a require-ment that is often at odds wit
h the ecological sciences (Thillman and Monasch1976;Felleman1992;Jenn et al.1993).For example,planners want to know ex-actly what habitat requires protection,where it is,how much,and in what configuration(Crist1994;Bennet et al.1995;Grant et al.1996;Jenn et al.1993).Ecol-ogists,on the other hand,are uncomfortable providing such information,given the uncertainties regarding species occurrence,demographics,species-species in-teractions,and ecosystem process(Felleman1992; Flather et al.1997;Truett et al.1994).Thomas et al. (1976:453)encountered a similar incongruity in forest planning and noted that the real problem was not lack of data but‘the lack of a conceptual framework sideration of all vertebrates in the planning process.’The challenge for ecologists,then,is to pro-vide information bad on the best available data and reasonable conclusions of the relationship of biotic needs to human activities(Thomas et al.1976;Thax-ton and Hingtgen1996;Truett et al.1994;Westman 1985).
课型分为哪几类Conrvation protection must occur at all spa-tial and temporal scales from global to site scale and short to long term.Although site-scale activi-ties are a prominent cau of biodiversity destruction (Schemske et al.1994),biotic element ranges span from meters to continents,and their entire range must be considered during conrvation planning(Hecnar and M’Closkey1997).Although jurisdictions at all scales(local,county,regional,state,national)need tools and methods tailored for their conrvatio
n plan-ning,we cho the state political subdivision of the county as our focus.The primary reason is that,lack-ing a regional government with police power,the county is usually the largest jurisdictional unit in the U.S.with authority to regulate land u(Jenn et al. 1993;Johnston and Madison1993).Further,it is the jurisdiction that is typically responsible for the ma-jority of undeveloped lands.The county is also an intermediate-sized unit to which a citizen can relate government action to their quality of life,and the county can act as a regional government incorporating the smaller jurisdictions within it.Press et al.(1996: 1539)found that the county scale‘matches the range sizes of many rare,,’making it an appropriate unit of analysis and conrvation for tho elements.Dobson et al.(1997)also found that species endangerment can be explained at the county level for many plants and animals.While we believe biodiversity conrvation ultimately requires cross-jurisdictional planning,our intent was to develop a system to deal with current realities.
大胸动漫人物
The need for biological expert system tools
We hypothesized that the most efficient and effective solution to local government consideration of biodi-versity is the u of an expert systems approach that can integrate data and knowledge needed by planners and provide them in a convenient system that allows immediate application to pl
anning activities.We t out to test this hypothesis through development of a pilot biodiversity expert systems tool(BEST).
An expert systems tool is a type of decision support system that aids the understanding and processing of complex information to support the decision-making process(Zhu et al.1998).We define an expert systems tool in the context of our rearch as one that incorpo-rates expert knowledge(Zhu et al.1998)into a system that allows easy retrieval of that knowledge to support decisions by non-experts.They are applicable to situ-ations where it is impractical or inefficient to maintain live interaction with the expert,becau it is either too costly or the need is too infrequent.In tho situations, it is more efficient to gather the information all at once and archive it in a databa(Zhu et al.1998).Local governments typically lack the resources to maintain access to biological experti(Simmens1996),their
49
need for such may not be continuous,and the de-sired information is too time consuming to asmble for answering individual inquiries.Therefore,the re-quirement of local governments to asss the potential impacts of propod human activities on biodiversity is ideal for an expert systems tool(nsu Zhu et al. 1998).
炒芹菜
The goal of our pilot system is to make the consid-eration of biodiversity in local government land-u planning and regulatory activities as routine as other commonly considered elements such as stormwa-ter management or prervation of scenic views. Stormwater management is a suitable analogy,be-cau it required many years of data collection and analysis-tool development by the federal government prior to becoming a common element of consideration at the local level(Environmental Protection Agency 1995).
An important objective was to develop a system that us existing public domain data and common commercial GIS software such that the system would be relatively simple and inexpensive to replicate.Plan-ners also noted the importance of having simple input and output information.They explained that a system would not be ud if it required lengthy and expen-sive upfront costs to implement,frequent updating and maintenance,and produced complex results that could not be directly applied to planning tasks(nsu Rogers1995).Above all,decision makers must trust the output from the system,which requires that the op-erator be able to explain how the result was derived.In other words,a black box system would not be accept-able(Reilly1997).Ourfinal objective was to learn, through development of the pilot,what the challenges are of developing a system suitable for nationwide application.
The primary deficiency in biodiversity conrva-tion planning has been data on the distribution and status of biotic elements;in other words,where might they be and how much are they in need of conr-vation?The Gap Analysis Program(GAP)(USGS Gap Analysis Program1998)is well under way to-ward the mission of providing such information on terrestrial vertebrates and plant communities for the entire United States,with aquatic element pilot pro-grams initiated as well(Jennings,this issue).In1996, the Wyoming Gap Analysis Project(WY-GAP)was completed(Merrill et al.1996)which motivated us to lect Teton County,Wyoming,for this pilot project (Figure1).Although we acknowledge that maps of vegetation communities and predicted distribution of terrestrial vertebrates are an imperfect surrogate for biodiversity(Scott et al.1993),we believe the GAP process and the BEST approach reprent an expand-able framework that can,ultimately,include all taxa. The data reprent the most extensive t of infor-mation compiled for any state on biotic distributions and conrvation status.Another benefit,besides cost-savings,of using public domain data is that planners are not put in the position of relying solely on data and analysis produced by applicants’consultants as the ba-sis for permitting decisions(Collins,). Additionally,the GAP data are well documented for production methods and accuracy,and are verifiable. Methods
BEST is compod of(1)a PC computer platform;
(2)GIS software with a custom interface to run the BEST applications(ArcView3using Avenue[En-vironmental Systems Rearch Institute1998]);(3) GIS map data including ba coverages for roads and streams,the county parcel coverage,the WY-GAP land cover coverage and predicted terrestrial verte-brate distribution coverages,and the county critical habitat coverages;(4)a table translating named land us into habitat impact categories;(5)tables for each biotic element relating nsitivities to the land-u habitat impact categories;and(6)documentation, including GIS coverage metadata,methodology,refer-ences for assigned rankings and mitigation measures, and additional help instructions(Figure2).The infor-mation components and reports generally replicate the NEPA process(Truett et al.1994)for jurisdictions not required and unable to undertake such thorough analy-s.This configuration was lected to meet our goals of simple,inexpensive u and replication.
走山
Becau no knowledge of GIS or ecology is as-sumed for the ur,the basic queries are constructed a priori with outcomes that are predictive of a gener-alized ,the impacts of a typical single-family subdivision are predicted and input into the system’s interpretation tables.To construct the tables, each land u must be"cross-walked"to a simpli-fied scheme that reframes the u in ecological terms by which the biotic elements can be assd for nsitivity.
The categorization system
The critical component in this system is a scheme that allows communication between land-u planners and
丁豆50
Figure1.Pilot study location.Teton County is located in the heart of the Greater Yellowstone Ecoregion.
济南公租房ecologists.This was accomplished by redescribing hu-man land us in ecologically meaningful terms that are uful to a biologist in establishing biotic nsitiv-ities to tho land us.Land-u schemes that are only descriptive in terms of human social systems(Blair 1996;Knight and Cole1995,Truett et al.1994)such as‘single family residential’are not informative as to ecological impacts,and reliance on intuitive interpre-tations would lead to arguments bad on viewpoint, not science.Alternatively,we developed a catego-rization scheme to relate the allowable land us in a local government jurisdiction to types and degrees of impact on habitat and species.We stress that this system distinguishes between management issues and land u.Land-u planners are not land managers; the local government reviews propod us,negoti-ates mitigating changes,and either approves or denies the u within the legal system.After approval,there is typically no additional land management role of the government other than to police the us. Parameters
We divided land-u impacts into two parameters, Land Cover Alteration and Human Prence Conflict to allow independent asssment of their impacts on each biotic element.We believe our approach will fa-cilitate better identification of alternative land us and more creative site designs that are compatible with the biota.Obviously,there are interactive effects between the parameters,but the complexity of determining the interactions and their impacts is beyond the scope of this system and perhaps beyond current scientific knowledge(Felleman1992;Flather et al.1997;Truett et al.1994).Each parameter is defined by a gradient of increasing levels of impact to allow simple,but sufficiently robust,categories that can capture all land us.
Land cover alteration parameter
The land cover alteration parameter refers to the de-gree that the natural land cover of the tract will be disturbed by the propod land u.As Truett et al. (1994:615)noted,‘alteration of habitat structure is usually the major and most easily perceived chan-nel through which human actions affect the wildlife community.’The general factors we considered are: proportion of area disturbed,type of disturbance,and intensity of disturbance.We specifyfive characteris-tics that determine the level of impact on land cover: structure(Short1983),species composition,domi-nant species(Maschinski et al.1997;Adams and Dove1989;Knight and Temple1995;Soulé1991), hydrologic regime(alteration of t
he surface and sub-surface waterflow)(Arnold and Gibbons1996),and natural disturbance ,suppressing natural fires)(Sampson1996;Soulé1991).Thefirst three characteristics refer to direct impacts on vegetation communities,while the latter two are indirect dis-
51 Figure2.An operational diagram of BEST.County land u designations and biotic element maps and information are inputs that are intre-preted for impacts and nsitivities.The are ranked in matrices(indicated by the center box)that become part of the system.The operator interacts with the maps,information,and expert knowledge through the interface.Rectangular boxes indicate outputs in the form of reports, mitigation suggestions,and graphic maps.
turbances that are also critical factors in ecological land-u planning(McHarg1969;Palmer1981).Im-pacts on hydrologic and natural disturbance regimes were more difficult to determine outright from land-u descriptions,but comparison with existing land us in the jurisdiction can be ud to determine their likelihood in propod land us(Urban et al.1987). Although some land us will allow for regeneration of some natural land cover,the existing plant commu-nity is rarely reestablished(Urban et al.1987).The ability of animal species to recolonize such an area is unknown becau the timeframe for reestablishment of the necessary habitat conditions cannot be assumed. Therefore,our categorization is made for the land-cover condition we assumed to exist upon completion of the initial development activity and full-intended occupancy.Thefive characteristics of land cover al-teration are each ranked according to four levels of impact resulting from a land u(Table1).
Each land u is then assigned a land cover impact level corresponding to the intensity of disturbance and the amount of the tract impacted(Appendix1).We allowed at least5%of the tract in all categories to be verely altered by such features as visitor facili-ties,trails,parking,etc.We found no empirical data in the literature to establish thresholds on the amount of the tract that may be subject to alteration,so we ud thresholds of impervious land cover suggested to cau measurable declines in overall watershed condi-tion(Arnold and Gibbons1996).The thresholds are
数学教师工作总结
>砖子苗
