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1、CropsstatisticsConcepts,definitionsandclassificationsII.PRIMARYCROPS•1.Primarycropsarethosewhichcomedirectlyfromthelandandwithouthavingundergoneanyrealprocessing,apartfromcleaning.Theymaintainallthebiologicalqualitiestheyhadwhentheywerestillontheplants
2、.•2.Certainprimarycropscanbeaggregated,withtheiractualweight,intototalsofferingmeaningfulfiguresonarea,yield,productionandutilization;forexample,cereals,rootsandtubers,nuts,vegetablesandfruits・Otherprimarycropscanbeaggregatedonlyintermsofoneortheotherc
3、omponentcommontoallofthem.Forexample,primarycropsoftheoil-bearinggroupcanbeaggregatedintermsofoiloroilcakeequivalent.•3.Primarycropsaredividedintotemporaryandpermanentcrops.Temporarycropsarethosewhicharebothsownandharvestedduringthesameagriculturalyear
4、,sometimesmorethanonce;permanentcropsaresownorplantedonceandnotbereplantedaftereachannualharvest.III.TEMPORARYPRIMARYCROPS:CONCEPTS,COVERAGEANDGENERALRECOMMENTATIONS•1.1Conceptofarea.Cropareaisasurfaceoflandonwhichacropisgrown.Ingeneral,theareameasured
5、forcadastralpurposesincludes,inadditiontotheareacultivated,headlands,ditchesandothernon-cultivatedareas.Suchanareacanbecalledgrossareaasagainstthenetareawhichincludesonlytheportionofthegrossareaactuallycultivated.Ithappensthatforvariousreasons,e.g.,nat
6、uralcalamitiesoreconomicconsiderations,certainareasplantedorsownwithagivencroparenotharvestedorareharvestedbeforethecropreachesmaturity.Hencetheneedfortheconceptofareatobesub-dividedintosownorplantedareaandharvestedarea・•Ithasbeenrecommendedthatcountri
7、esreportnetareasownandnetareaharvested.Countrieswhichnormallydonotpresentdataforharvestedareawererequestedtoshowthesefigures,atleastwhentheharvestedareadifferssignificantlyfromthenormally-reportedarea.Dependingonthedateofenumeration,itcouldbepossibleth
8、atsownandharvestedareaarepracticallyidentical.Sownareadataarenecessarytoestimatequantitiesusedforseedingpurposes;harvestedarea,toprovidereliableandaccurateyieldandproductiondata.•1.2Coverageofarea・Incertaincountries,theunitofenumeration
