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1、FAOStatistics::January2011CropsstatisticsConcepts,definitionsandclassificationsII.PRIMARYCROPS·1.Primarycropsarethosewhichcomedirectlyfromthelandandwithouthavingundergoneanyrealprocessing,apartfromcleaning.Theymaintainallthebiologicalqualitiestheyhadwhentheywe
2、restillontheplants.·2.Certainprimarycropscanbeaggregated,withtheiractualweight,intototalsofferingmeaningfulfiguresonarea,yield,productionandutilization;forexample,cereals,rootsandtubers,nuts,vegetablesandfruits.Otherprimarycropscanbeaggregatedonlyintermsofoneo
3、rtheothercomponentcommontoallofthem.Forexample,primarycropsoftheoil-bearinggroupcanbeaggregatedintermsofoiloroilcakeequivalent.·3.Primarycropsaredividedintotemporaryandpermanentcrops.Temporarycropsarethosewhicharebothsownandharvestedduringthesameagriculturalye
4、ar,sometimesmorethanonce;permanentcropsaresownorplantedonceandnotbereplantedaftereachannualharvest.III.TEMPORARYPRIMARYCROPS:CONCEPTS,COVERAGEANDGENERALRECOMMENTATIONS·1.1Conceptofarea.Cropareaisasurfaceoflandonwhichacropisgrown.Ingeneral,theareameasuredforcad
5、astralpurposesincludes,inadditiontotheareacultivated,headlands,ditchesandothernon-cultivatedareas.Suchanareacanbecalledgrossareaasagainstthenetareawhichincludesonlytheportionofthegrossareaactuallycultivated.Ithappensthatforvariousreasons,e.g.,naturalcalamities
6、oreconomicconsiderations,certainareasplantedorsownwithagivencroparenotharvestedorareharvestedbeforethecropreachesmaturity.Hencetheneedfortheconceptofareatobesub-dividedintosownorplantedareaandharvestedarea.·Ithasbeenrecommendedthatcountriesreportnetareasownand
7、netareaharvested.Countrieswhichnormallydonotpresentdataforharvestedareawererequestedtoshowthesefigures,atleastwhentheharvestedareadifferssignificantlyfromthenormally-reportedarea.Dependingonthedateofenumeration,itcouldbepossiblethatsownandharvestedareaarepract
8、icallyFAOStatistics::January2011identical.Sownareadataarenecessarytoestimatequantitiesusedforseedingpurposes;harvestedarea,toprovidereliableandaccurateyieldandproductiondata.·1.2Co
