DEVELOPMENT AND SUSTAINABILITY IN THE RIVER GUAJIRU/RN HYDROGRAPHIC BASIN: A CONTRIBUTION TO ENVIRONMENTAL PLANNING BASED ON LAND AND WATER USE
Ambiental degradation; Useandcoverageoftheland; waterquality; Wateravailability
The disorderlygrowth of cities, linkedtotheprocess of industrialization and expansion of agriculturalactivity, contributed over time totheemergence and worsening of environmentalproblems in watersheds. The use and occupation of land in these territorial planningunitshasbeenshowntobeone of the processes withthegreatestimpactonthephysicalenvironment, promotingenvironmentaldegradationthat, consequently, compromisestheavailability of natural resources for thepopulation. Thisresearchhad as object of studythe Guajiru River Basin (BHRG) locatedontheeastcoast of Rio Grande do Norte, with a total area of 120 km², comprisingthemunicipalities of Natal, Ceará Mirim, Extremoz, São Gonçalo do Amarante and Ielmo Marinho. Thisbasinwasselected for studiesbecause of its environmental and socioeconomicimportance, withpotential for thedevelopment of irrigatedagriculture in rural areas and because it drainsintoone of themostimportantreservoirs in eastern Potiguarused for publicsupply, whichis Lagoa de Extremoz. The general objectivewastocharacterize and mapthepattern of humanoccupation in terms of land use and land cover, the legal conflicts and theresultingdegradation and theavailability and quality of water, in ordertotrytounderstandthecurrentsituation of thebasin'sphysicalenvironment. totrytosubsidize territorial planningstudies. The methodological procedures coveredtheliterature review, thesurvey of spatial data and cartographicinformation, theselection and processing of the Sentinel 2 scene, thesurvey of well data, therecording of fieldobservations and thecollection of samples for analysis of waters, in fieldstagesthatalsoservedtogeoreference, describe and record data and informationcollected and samples for wateranalysis. The data wereprocessed and maps of land use and land cover, of APPs and legal conflicts and extension of waterlayers of surface springsweregenerated, usingthe Terrahidro/Terraview 086x and Qgis in version 3.16.11 applications. Withthemap of land use and cover, it wasfoundthatpastures cover 30% of thebasinarea, followedby open treeshrub caatinga, with 21.9%. The anthropizedfields, occupiedbyagriculturalactivities, represent 19%, and thelayers of waterbodiesoccupy 0.9% of theland surface. The map of land use and land cover in APPs shows that 32.9% of theseareas are occupiedbypastures, and 8.1% byanthropicactivities. Field data and informationvalidatetheresults and attestthat legal conflicts and environmentaldegradation in thebasin are widelydistributed, withgreaterimpacts in thespringareas, and strictlyassociatedwithdisorderlyhumanoccupation. Of the 164 wellsregisteredatbacai, 132 of them do notcontaininformationonthesituation. Of the total registeredwells, 149 are of a privatenaturewithdepthrangingfrom 3 to 160 meters, 46 do notcontainthedepth and, and only 3 privatewellshaveinformationonwaterquality. The 14 publicwells are tubular withdepthsrangingfrom 18 to 85 meters, and onlythreehave complete informationonwaterquality. The analyzes show in summarythatthethreecollectionscarried out in wells are currentlyunfit for humanconsumption, duetotheir pH beingbelow 6 and thepresence of thermotolerantcoliforms in all samples fromthewells in accordancewith Conama resolution 396 of 2008 Withregardtowateravailabilityfrom surface sources, its quality for consumption in rural communitiesiscompromised and its use isriskywithout prior treatment. Accordingtotheresultspresented in thisresearch, humanoccupation in the Guajiru River Basinhasbeencontributingtoimpact and degrade natural resources, especially surface sources. Thus, thereis a need for furtherresearchtogenerate new informationthatcontributestotheproperplanning of land and water use and thataimsatenvironmentalrecovery and territorial reorganization of areas of permanent preservation.