However, Some Errors May Remain. PERENNIAL FORB LIFE .
This file was created by scanning the printed publication.Errors identified by the software have been corrected;however, some errors may remain.PERENNIAL FORB LIFE-HISTORYSTRATEGmS ON SEMIARIDRANGELANDS: IMPLICATIONSFOR REVEGETATIONStanley G. KitchenABSTRACTaboveground structures. As a general rule, these plantshave relatively rapid potential growth rates; there is noinvestment in aboveground woody tissues. Because theyrun the risk of being shaded by taller woody species, somebenefit from frequent aboveground disturbance such asherbivory and fire. Herbaceous perennials are dividedinto two fairly distinct groups: grasses and grasslike species and forbs (dicots and some monocots). Though extremely diverse, perennial forbs are competitively distinctfrom grasses, differing significantly in anatomical, physiological, and reproductive features.The seasonal nature of resource pulses in the Intermountain West favors species with perennial life histories. Theoften short and unpredictable growing season (as dictatedby soil moisture and soil and air temperature) typical ofvalley and foothill landscapes results in numerous combinations of perennial shrub, grass, and forb species (Ream1963). Perennial forb species are responsible for muchof the diversity in these communities even though coolseason grasses often dominate the herbaceous component.Frequent spring cold spells and a continental climate alsofavor wind-pollinated grasses and shrubs over the predominantly insect-pollinated forbs. Forb diversity is generally greater in communities associated with more mesicsites. On these sites, the canopy cover of tall shrubs andtrees may increase, resulting in a shift to conditions thatfavor shade-tolerant forbs.Establishment and persistence ofperennial (orbs arepriority objectives in revegetation. Species adapted tosemiarid regions of the Western United States employ lifehistory strategies suited to unpredictable and often extreme environmental conditions. Long-lived (orbs growrapidly in spring and survive drought through vegetativedormancy. Short-lived species are opportunistic and utilize soil seed reserves to persist through long periods ofunfavorable conditions. Seeded (orbs must be adapted tosite conditions for successful establishment and long-termsurvival.INTRODUCTIONThe evolution of terrestrial plant morphologies reflectstradeoffs between maximization of growth rates by allocation of photosynthate to production and display of photosynthesizing tissues (principally leaves) and the need toinvest in other structures (roots, stems) needed to survivein resource-limited environments (Tilman 1988). The development of roots increases in importance as soil resources(such as water and mineral nutrients) become less available. Conversely, plant height becomes increasingly important as soil-surface light intensity decreases due toincreases in plant canopy shade, a change generally associated with increases in soil resource levels. Plant height isgreatly increased through the development of perennial(woody) stems. The "cost" of root and stem investment isa decrease in growth rate. Competitive strength of a species is dictated by its ability to adjust photosynthate allocation between plant parts, balancing the tradeoff betweengrowth rate and stress tolerance for the often-changing conditions of its environment.Perenniality is generally favored in environments experiencing seasonal pulses in resource availability (Tilman1988). While increases in both frequency and severity ofdisturbance favor annual growth, herbaceous perennialsmay be favored when disturbance-caused losses are primarily to aboveground structures.Herbaceous perennials are characterized by perennating belowground structures and herbaceous, nonwoody,PERENNIAL FORB STRATEGIESGrime (1977) proposed three primary plant strategiesin which traits have evolved in response to different levelsof competition, stress, and disturbance. He describedcompetitive, stress-tolerant, and ruderal strategies, eachadapted to conditions of high levels of one of these environmental forces and lesser levels of the remaining two.He also described conditions that select for secondary orintermediate strategies and suggested that perennialforbs have a range of strategies wider than other plantgroups.Successful forb strategies have evolved to address bothnorms and extremes of the environment. Physical factorssuch as dependability of growing season, severity andlength of drought, and nature and frequency of disturbance are important in determining the "shape" of eachstrategy. Abrahamson (1979) documented differences inresource allocation between forb species and ecotypes associated with forest understories and those found in openfields. Field forbs allocated a greater share of resources toPaper presented at the Symposium on Ecology, Management, and Restoration of Intermountain Annual Rangelands, Boise, ID, May 18-22, 1992.Stanley G. Kitchen is Botanist, Shrub Sciences Laboratory, Intermountain Research Station, Forest Service, U.S. Department of Agriculture,Provo, UT 84606.342
reproductive organs and a lesser share to leaves andbelowground organs than did forest understory species.Specialized animal pollination strategies are favored inwooded understory habitats because of improved efficiencyin long-distance pollination among dispersed plants bearing relatively few flowers (Regal 1977).This paper describes life-history strategies suited tonon- or open-forested habitats and gives examples nativeto the Intermountain West.most plants do not flower for several years after seedlingestablishment (Shaw and Monsen 1983).Other long-lived forb species used in revegetation withhigh levels of belowground resource storage includePacific aster (Aster chilensis), western yarrow (Achilleamillefolium), Louisiana sagewort (Artemisia ludoviciana),and scarlet globemallow (Sphaeralcea coccinea) (Menkeand Trlica 1981; Shaw and Monsen 1983). As with thesespecies, belowground reserves are often related to vegetative reproduction. Allium, Calochortus, Erigeron, Eriogonum, Lomatium, Senecio, Solidago, and Wyethia are examples of other forb genera represented by Strategy Aspecies.Strategy A: Long-Lived/SummerDormantStrategy A species are typically slow to reach reproductive maturity and are long lived. They inhabit communities where the favorability of microsites is relativelyconstant (Gadgil and Solbrig 1972). Resource pulses aregenerally predictable (seasonal) and at least adequate formaintenance growth. This strategy is intermediate between the competitive and stress-tolerant strategies proposed by Grime (1977), though species are also tolerantof some forms of disturbance.A distinguishing trait of Strategy A species is the storage of large quantities of mineral resources and photosynthate in belowground perennating structures. These reserves are mobilized rapidly to produce photosynthesizingleaves and stems early in the growing season, making mature plants excellent competitors. Reproductive outputintensity is tied to these stored reserves; mast seed production (cycles ofbumper crops spaced by years of minimal or no seed production) is common. Summer droughtis avoided through vegetative dormancy. The successfulestablishment of new individuals or cohorts may be eitherslow and gradual or rare, as these species are typically associated with somewhat closed, late seral communities(Gadgil and Solbrig 1972).Arrowleafbalsam.root (Balsamorhiza sagittata) is atypical Strategy A species. This long-lived species produces a large taproot with deep soil penetration (Shawand Monsen 1983). Large basal leaves emerge quicklyfrom the taproot as spring conditions permit. Mast seedproduction is synchronized, at least in part, by the effectsof weather (such as precipitation and spring frost) onresource allocation. Plants enter dormancy in early tomidsummer.Seeds are relatively large and are sought out andcached by rodents (Everett and others 1978). Seed dormancy prevents precocious summer or fall germination.Young and Evans (1979) speculated that excessive seedstratification requirements reduce spring germination.In laboratory experiments, I found that seed dormancy isbroken with moderate periods of moist chilling (stratification) (Kitchen 1993). Mean germination percentages for10 collections after 8 and 10 weeks of moist chilling were59 and 91 percent, respectively. In a parallel field retrieval experiment conducted on an arid Wyoming sagebrush (Artemisia tridentata spp. wyomingensis) site insouthern Idaho, less than 1 percent of seeds planted inmidsummer and fall remained dormant in the followingspring. Seedling growth and maturation rates are slow;343Strategy B: Short-Lived, OpportunisticStrategy B is associated with species that experienceepisodic recruitment and die-off events, often correlatedwith extreme weather events or harsh disturbance.Though these species usually benefit from seasonal pulsesin soil moisture, vegetative and reproductive growth responses can occur any time effective moisture becomesavailable and temperatures permit. High mortality ratesoften follow explosive seed production events apparentlydue to depletion of stored reserves (Fenner 1985). Speciesare generally classified as short lived. Strategy B is bestdescribed as a stress-tolerant ruderal strategy whenGrime's (1977) classification is applied.Strategy B species rapidly reach reproductive maturityand have a proportionately high investment of resourcesin seed production (Fenner 1985; Gadgil and Solbrig1972). Individual seeds require relatively small investments in resources and are mobile, allowing the speciesto explore numerous new sites on both a spatial and temporal scale. Seed dormancy mechanisms, such as hardseededness, that function to ensure that a portion of theseeds produced are committed to a soil seed reserve (remain ungerminated through periods favorable for seedling growth) are essential for species or ecotypes employing this strategy. The successful establishment of newcohorts, though more common than with Strategy A species, is probably tied to disturbance events or sequences ofone or more seasonal pulses with higher than normal amplitude or longer than normal duration.A good example of a Strategy B species is Palmer penstemon (Penstemon palmeri). This short-lived perennialforb flourishes on disturbed sites such as washes and canyon bottoms (Cronquist and others 1984). Populationshave been successfully established and have persisted onhuman-caused disturbances such as roadcuts. When soilmoisture is plentiful during the growing season, matureplants produce copious quantities of seeds. Typically,these plants become weakened and many die by the following spring (personal observation). Mortality is likelydue, at least in part, to stresses caused by high reproductive output. Cold-induced seed dormancy, a light requirement, and a long imbibition requirement before radicalemergence ensure maintenance of a soil seed reserve(Kitchen and Meyer 1992; Meyer and Kitchen 1992).Numerous other penstemon species exhibit strategies for
preserving a soil seed reserve (Kitchen and Meyer 1991;Meyer 1992; Meyer and Kitchen 1993).Gooseberry-leaf globemallow (Sphaeralcea grossulariifolia) has a strategy similar to that of Palmerpenstemon. This short-lived species (West 1979) is welladapted to drought and is widely distributed in desertshrub, pinyon-juniper, and low-elevation mountain brushcommunities (Welsh and others 1987}. Persistent soilseed reserves allow populations to cycle in response tovariable weather patterns (Sharp and others 1990). Typically, extended periods of favorable conditions result inpopulations spending themselves in explosive reproductive events often followed by episodic die-off (personal observation). The strategy of the closely related munroglobemallow (S. munroana) is similar.100-goQaoas- ----- ::- ··------ "-.CD.cCl)e8.'ii · :::»tn70- Asotin, WAeo ALava, 105040 Cove Fort, UTo Mona, UT302010- Provo, UTo- \- '-,.- ::." ""'' '"A,· '\\ -. . '\ \\\'\\,\. \.··,, 'o'·,,'-.\ ---- -- Potosi, NE\ Confusion Range, UT1989"'-.1990 19911992Rating Seasonlntermne ateStrate esFigure 1-Survival of Lewis flax collections in acommon garden near Nephi, UT. Greenhouse reared seedlings were transplanted in April 1989.Mortality from 1990 to 1991 was significantly correlated with an index of severity of rust infection(p 0.05, r 2 0.75). All plants were treated forrust in 1991, minimizing infection. Mortality from1991 to 1992 is presumed unrelated to rust infection. The cultivar 'Appar' belonging to the European species perennial blue flax (Linumperenne), remained free of infection though itexperienced 26 percent mortality, similar to thatexperienced by some of the North AmericanLewis flax collections.Strategies A and B are not mutually exclusive. Specieswith intermediate strategies combine elements of both.In addition, the relative importance of each strategy, asexpressed by key traits, may vary considerably amongecotypes of a single species occupying a wide range ofhabitats. This variability is not surprising when the differences in moisture regime, disturbance factors, andcompetition patterns among these habitats are considered. Solbrig and Simpson (1974) observed phenotypicvariability in seed production and competitive abilityamong biotypes of common dandelion (Taraxacum officinale). Biotypes with relatively high reproductive outputdominate on sites with frequent disturbance (mowing),while more competitive biotypes dominate less frequentlydisturbed sites.Ecotypes of Lewis flax (Linum lewisii) are adapted toshadscale, sagebrush, pinyon-juniper, grassland, mountain brush, ponderosa pine, aspen, and spruce-fir communities (Welsh and others 1987). In a common garden studywith populations selected from diverse habitats, reproductive output varied by more than two times as measured byflower number and total seed weight per plant (Kitchenand others 1993). After 3 years, mortality among ecotypes ranged from 3 to 100 percent (fig. 1). Differentialresistance of ecotypes to rust infection significantly contributed to differences in second-year losses. Short-livedecotypes subject to frequent density-independent mortality events may gain little or no advantage by investing inrust resistance. In addition, much of the mortality over a3-year period occurred in plants that were rust-free andprolific during the year before death, suggesting that patterns of reserve depletion during seed production may beimportant to longevity among ecotypes of this and possibly other species (Gadgil and Solbrig 1972).In laboratory germination studies with Lewis flax seeds,a significant fraction of seeds developed cold-induced secondary dormancy for five of21 collections tested (Meyerand Kitchen, in press). Nine of the remaining collectionshad a portion (13 to 68 percent) of viable seeds that didnot become germinable after 24 weeks of stratification.Field retrieval experiments verified the ability of this species to seedbank for multiple years. These results suggestthat Lewis flax tactics include provisions for maintaininga soil seed bank, and that the relative importance of aseed bank varies among ecotypes.Another forb with an intermediate strategy is northernsweetvetch (Hedysarum boreale). This moderate tolong-lived legume is most common in midelevationcommunities and may have been reduced in distributionand density by past overgrazing (Plummer and others1968). Its roots penetrate deeply into the soil. Vegetativedormancy occurs as soil moisture is reduced in mid to latesummer. First bloom occurs in spring to midsummer. Asecond minor flowering sometimes results when initialfruit set fails (personal observation). Both weather andcarbohydrate reserves probably play an important role indetermining the intensity of single-year reproductive allocation. Seeds are generally hard (do not imbibe water)(Kitchen and others 1987; Redente 1982) and are soughtout and possibly cached by rodents. The hard-seeded traitallows for a significant portion of uneaten seeds to carryover in the soil. The species responds favorably to removal of competitive shrub species such as big sagebrush(Artemisia tridentata) and Gambel oak (Quercusgambelii). Large increases in vegetative and reprodu?tiveoutput are common following fires (personal observation).EMPUCATIONSFORREVEGETATIONFamiliarity with perennial forb strategies is essential toavoid costly mistakes in revegetation projects and in formulating appropriate expectations for seeded species inmodified environments. Species and ecotype life-historystrategy must be matched to planting site environmentalconditions. The following questions and discussions344
cons derationfor any seeding project. However, if seededspecies are short lived, requiring relatively frequentrecruitment episodes, long-term persistence may be prevented by weeds.5. Will a fraction of viable seeds remain ungerminatedafter the first season of growth? The seeds of most rangeland species are best planted in the fall. This permitsmoist chilling of dormant seeds and accelerates springgermination and growth of nondormant seeds. A viableportion of the seeds of many forbs, including penstemons,globemallows, Lewis flax, and northern sweetvetch, willremain ungerminated the first spring following planting(Strategy B). A knowledge of the seed-banking tendenciesof each species is useful in planning seeding rate and injudging first- and subsequent-year establishment success.Germination percentage can be increased for some speciesusing appropriate seed pretreatments. For example, hardseeded species such as sweetvetch and globemallows can bescarified prior to planting (Redente 1982; Roth and others1987) while species such as Lewis flax need only time indry storage to increase first-year germination (Meyer andKitchen, in press). Such tactics conserve the genetic capacity for seedbanking, a trait important for the longterm persistence of some species and ecotypes.6. How important is seed size in planning seeding rateand method? The seeds of some forb species are verysmall (table 1) and are not able to emerge from typicaldrilling depths. These seeds must be sown at or near thesoil surface. Seeding rates of these species can often bequite low, a real plus considering the cost of obtaining theseeds.should be addressed in determining appropriate species orecotypes for each revegetation project.1. Is the species adapted to the climate of the site? Forexample, when considering precipitation, seasonality andextremes may be as important as annual means in affecting success.2. Is the expected disturbance regime compatible withthe long-term persistence of each planted species? Disturbance effects can be positive or negative depending on thenature and timing of their occurrence. Intensity and frequency of disturbance are also important. For example,occasional fire is beneficial for northern sweetvetch andarrowleafbalsamroot, because of fire's negative effect oncompeting species, while herbivory is not. Other speciessuch as Palmer penstemon benefit from frequent soil erosion such as is found on steep slopes and in wash bottoms.The severity of damage, if any, to perennial forbs causedby selective herbivory and trampling associated withlarge ungulates (whether livestock or wildlife) is largelydependent on season of use. There may be times when itis appropriate to plant Strategy B species on sites wherethey may not persist; their value is as nurse plants forlater seral species.3. Are the forb species to be seeded compatible withother seeded species and remnant perennials on this site?An understanding of the competitive relationships amongspecies in seeded communities is largely lacking, so evalu":tion of this question is difficult. At the very least, caution should be used to not overplant aggressive long-livedgrasses on sites where a good representation of forbs isdesired.4. How weed prone is the site? Competition from annualgrasses such as cheatgrass (Bromus tectorum), medusahead (Taeniatherum asperum), and jointed goatgrass(Aegilops cylindrica) inhibits successful establishmentof perennial seedlings. Weed control should be a standardTableEfficacy in the use of a great variety of perennial forbspecies will improve as research provides a more completeunderstanding of perennial forb life-history strategies andtheir interactions within different communities. Many species with potential value are presently poorly understood.1-s edsize (seeds/lb) for 10 native perennial forb species. Quantities reported are adapted fromK1tchen and other (198 ) and Shaw an Monsen (1983). Recommended seeding rates (lblacre) arebased n the spectes betng a part of a dtverse seed mix. Alfalfa and small burnet are included forcompansonRecommendedseeding rateScientific nameSeedweightWestern yarrowLouisiana sagewortPacific asterArrowleaf balsamrootLewis flaxPalmer penstemonFirecracker penstemonRocky n sweetvetchAchillea millieoliumMemisia ludovicianaAster chilensisBa/samorhiza sagittataLinum lewisiiPenstemon palmeriPenstemon ,000350,0000.10.20.51.00.250.250.5Penstemon strictusSphaeralceagrossulariifoliaHedysarum boreale760,0000.25500,00059,0000.751.5AlfalfaSmall burnetMedicago sativaSanguisorba minor225,00045,0000.52.0Common 3.04.03.04.0
Our success in managing diverse communities in thesemiarid West will depend on carefully planned researchand its application.Meyer, S. E. 1992. Habitat-correlated variation infirecracker penstemon (Penstemon eatonii Gray:Scrophulariaceae) seed germination response. Bulletinof the Torrey Botanical Club. 119:268-279.Meyer, S. E.; Kitchen, S. G. 1992. Cyclic seed dormancy inthe short-lived perennial Penstemon palmeri. Journal ofEcology. 80: 115-122.Meyer, S. E.; Kitchen, S.- G. [In press]. Life history variation in blue flax (Linum perenne: Linaceae): seed germination phenology. American Journal of Botany.Meyer, S. E.; Kitchen, S. G. 1993. Habitat-correlatedvariation in seed germination response to chilling inPenstemon Section Glabri (Scrophulariaceae). Provo,UT: U.S. Department of Agriculture, Forest Service,Intermountain Research Station. 37 p. Review draft.Plummer, A. P.; Christensen, D. A.; Monsen, S. B. 1968.Restoring big-game range in Utah. Publ. 68-3. SaltLake City, UT: Utah Division ofFish and Game. 183 p.Ream, R. R.1963. The vegetation of the Wasatch Mountains, Utah and Idaho. Madison, WI: University ofWisconsin. 178 p. Dissertation.Redente, E. F. 1982. Sweetvetch (Hedysarum boreale var.boreale) seed germination. Journal of Range Management. 35: 469-4 72.Regal, P. R. 1977. Ecology and evolution of floweringplant dominance. Science. 196: 622-629.Roth, T. E.; Holecheck, J. L.; Hussain, M. Y. 1987. Germination response of three globemallow species to chemical treatment. Journal of Range Management. 40:173-175.Sharp, L.A.; Sanders, K.; Rimbey, N. 1990. Forty years ofchange in a shadscale stand in Idaho. Rangelands. 12:313-328.Shaw, N.; Monsen, S. B. 1983. Nonleguminous forbs forrangeland sites. In: Monsen, S. B.; Shaw, N., comps.Managing Intermountain rangelands-improvement ofrange and wildlife habitats. Gen. Tech. Rep. INT-157.Ogden, UT: U.S. Department of Agriculture, Forest Service, Intermountain Research Station: 123-131.Solbrig, 0. T.; Simpson, B. B. 1974. Components of regulation of a population of dandelions in Michigan. JournalofEcology. 62: 473-486.Tilman, D. 1988. Plant strategies and the dynamics andstructure of plant communities. Princeton, NJ:Princeton University Press. 360 p.Welsh, S. L.; Atwood, N. D.; Higgins, L. C.; Goodrich, S.1987. A Utah flora. Great Basin Naturalist Memoirs 9.Provo, UT: Brigham Young University. 894 p.West, N. E. 1979. Survival patterns of major perennials insalt desert shrub communities of Southwestern Utah.Journal of Range Management. 32:442-444.Young, J. A.; Evans, R. A. 1979. Arrowleafbalsamrootand mules ear seed germination. Journal of RangeManagement. 32:71-74.REFERENCESAbrahamson, W. G. 1979. Patterns of resource allocationin wildflower populations of fields and woods. AmericanJournal of Botany. 66: 71-79.Cronquist, A; Holmgren, A. H.; Holmgren, N. H.; Reveal,J. L.; Holmgren, P. K. 1984. Intermountain flora; vascular plants of the Intermountain West, U.S.A. (vol. 4).Bronx, NY: New York Botanical Garden. 573 p.Everett, R. L.; Meeuwig, R. 0.; Stevens, R. 1978. Deermouse preference for seed of commonly planted species,indigenous weed seed, and sacrifice foods. Journal ofRange Management. 31: 70-73.Fenner, M.1985. Seed ecology. New York: Chapman andHall.151 p.Gadgil, M.; Solbrig, 0. T. 1972. The concept ofr- and Kselection: evidence from wild flowers and some theoretical considerations. The American Naturalist. 106:14-31.Grime, J.P. 1977. Evidence for the existence of three primary strategies in plants and its relevance to ecologicaland evolutionary theory. The American Naturalist. 111:1169-1194.Kitchen, S. G. 1993. Seed dormancy and seed-bed requirements of arrowleaf balsamroot (Balsamorhizasagittata). Data on file at: U.S. Department of Agriculture, Forest Service, Intermountain Research Station,Shrub Sciences Laboratory, Provo, UT; RWU 4251 files.Kitchen, S. G.; Meyer, S. E. 1991. Seed germination ofIntermountain penstemons as influenced by stratification and GAa treatments. Journal of EnvironmentalHorticulture. 9: 51-56.Kitchen, S. G.; Meyer, S. E. 1992. Temperature-mediatedchanges in seed dormancy and light requirement forPenstemon palmeri (Scrophulariaceae). Great BasinNaturalist. 52:53-58.Kitchen, S. G.; Meyer, S. E.; Monsen, S. B. 1993. Lifehistory variation in Lewis flax (Linum lewisii: Linaceae): fecundity and plant longevity. Data on file at:U.S. Department of Agriculture, Forest Service, Intermountain Research Station, Shrub Sciences Laboratory,Provo, UT; RWU 4251 files.Kitchen, S. G.; Meyer, S. E.; Wilson, G. R.; Davis, J. N.;Stevens, R. 1987. Addition of Hedysarum borealenorthern sweetvetch to the Rules. Association of OfficialSeed Analysts Newsletter. 61: 65-66.Menke, J. W.; Trliea, M. J. 1981. Carbohydrate reserve,phenology, and growth cycles of nine Colorado rangespecies. Journal of Range Management. 34:269-277.346
Frequent spring cold spells and a continental climate also favor wind-pollinated grasses and shrubs over the pre dominantly insect-pollinated forbs. Forb diversity is gen erally greater in communities associated with more mesic sites. On these sites, the canopy cover of tall shrubs and tr
Errors and Data Analysis Types of errors: 1) Precision errors - these are random errors. These could also be called repeatability errors. They are caused by fluctuations in some part (or parts) of the data acquisition. These errors can be treated by statistical analysis. 2) Bias errors - These are systematic errors. Zero offset, scale .
Some hard errors are not preceded by any soft errors (96 out of 157 61%) # limited ability of those soft errors to predict hard errors. – There are additional facets of soft errors that may be fruitful to study, e.g., CHS info to identify
of errors of various types. Therefore, teachers of essay writing need to anticipate certain common types of errors. They may also find other types of errors, which can be revealed by analyzing the written products or essays of students. These are the conventions, which are usually followed by the teachers of writing when analyzing students' errors.
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Chapter 9 Correlated Errors. Learning Objectives Demonstrate the problem of correlated errors and its implications Conduct and interpret tests for correlated errors Correct for correlated errors using Newey and West’s e
Errors and fraud by households applying for SNAP benefits can result in improper payments. Errors are unintentional, while fraud is the intentional violation of program rules. Errors and fraud by state agencies—agency errors can result in inadvertent improper payments; the discussion of agency fraud largely focuses on certain
Electronic Instrumentation 10IT35 Dept. of ECE-SJBIT Page - 4 - INDEX SHEET SL.NO TOPIC PAGE NO. 1 University syllabus 1-3 PART - A UNIT - I: Introduction 8 to 30 a. Measurement errors: Gross Errors and Systematic Errors Absolute Errors and Relative Errors Accuracy Precision Resolution Significant Figures b.
articles. The total number of errors found in active and passive voice was 506 which came to 28.8%. The number of errors made by Iranian at pre-university level in the use of tense was 580. They constituted 33% of errors for tenses. Khansir (2013) analyzed the written errors such as punctuations, articles, spellings and conjunctions in the .
