Ngā Tikanga Tukatuka Whakaahua Amiorangi i roto i te Ahupūngao Whenua
Kua noho te tirohanga mamao e ahu mai ana i te amiorangi hei poutokomanawa nui mō ngā rangahau me ngā tono matawhenua o ēnei rā. Mā te whakaahua amiorangi, ka taea e ngā tohunga matawhenua te tirotiro whānui, i ia wā, me te auau i te mata o te Ao—mai i ngā āhuatanga matawhenua me ngā whanaketanga tektonika ki ngā huringa takutai moana me te whakarerekētanga o te mata i puta mai i ngā rū whenua, i ngā mahi puia rānei. Heoi, kāore e taea te whakamahi wawe i ngā whakaahua amiorangi. Me whai raupapa tikanga tukatuka hei whakapai ake i te kounga o ngā raraunga, hei tango i ngā mōhiohio matawhenua e tika ana, me te whakaiti i ngā pokanoa pēnei i ngā kapua, te haruru, te whakapōturitanga āhuahanga rānei. Ka matapakihia e tēnei tuhinga ngā tikanga matua mō te tukatuka whakaahua amiorangi i roto i te horopaki matawhenua, mai i te tukatuka-mua ki te tātari matatau.
1. Ngā momo whakaahua amiorangi e whakamahia whānuitia ana i roto i te matawhenua
I roto i te matawhenua, he maha ngā momo raraunga amiorangi e whakamahia ana:
1. Ngā tirohanga maha-āhua (hei tauira, Landsat, Sentinel-2)
Ka whakarato i ngā mōhiohio whakaata o te mata i ngā roangaru maha. He pai mō te mahere i te hanganga o ngā kohatu, ngā kohuke whakarerekētanga, ngā tipu (hei tohu ā-kore mō ngā āhuatanga o te oneone), me ngā huringa whenua.
2. Te Wera (hei tauira, Landsat TIRS, MODIS)
Te ine i ngā tukunga wera mata mō te tātaritanga rerekētanga wera, hei tauira, te aroturuki i ngā puia, ngā rerenga rangitoto, ngā huringa pāmahana mata e pā ana ki ngā mahi waiariki.
3. Rātari (Rātari Pūwero Hanga/SAR: Sentinel-1, ALOS PALSAR)
He kaha ki te uru ki ngā kapua, ā, ka mahi tonu i te ao, i te pō, he mea nui mō te mahere i ngā hanganga, i ngā huringa o te mata, me te tātari i te whakarerekētanga ma te whakamahi i ngā tikanga InSAR.
4. Te ine i te teitei me te kaha ā-papa o te amiorangi (hei tauira, CryoSat, GRACE/GRACE-FO)
Ahakoa ehara i te "whakaahua" i te tirohanga tuku iho, ka tukatukahia ēnei raraunga hei mahere matawhenua pērā i ngā panonitanga o te papatipu wai, ngā rerekētanga o te kaha ā-papa, ngā panonitanga rānei o te matotoru o te huka.
Mā te kōwhiringa o te momo raraunga e whakatau te rere o te tukatuka tika, nā te mea he rerekē ngā āhuatanga haruru, te whakataunga, me ngā āhuatanga ā-tinana o ngā tohu.
2. Te tukatuka i mua: te tūāpapa o te kounga tātari
Ko te whāinga o te wāhanga tukatuka-mua he whakarite i ngā raraunga kia pai ai mō te tātari tauanga, kia taea ai hoki te whakarite i roto i te wā, i waenga rānei i ngā pūoko.
a. Ngā whakatikatika irahiko me te āhuarangi
Ka hopukina e ngā whakaahua whatu te kaha, e pāngia ana e ngā āhuatanga o te āhuarangi (ngā aerosol, te mamaoa wai) me te koki o te hihi o te rā. Ka hurihia e te whakatikatika ine irirangi ngā uara matihiko (DN) ki te whakaata ā-tinana, ki te kanapa rānei. Mā te whakatikatika āhuarangi—hei tauira, mā te whakamahi i te tikanga Tangohanga Mea Pōuri, i ngā huarahi tauira āhuarangi rānei—ka āwhina ki te whakaputa i te whakaata mata tika ake. I roto i te ahupūngao matawhenua, he mea nui tēnei kia whakaata pono ai ngā rerekētanga o ngā uara hihi i ngā rerekētanga o ngā rauemi mata, o ngā āhuatanga rānei, kaua ki ngā huringa āhuarangi.
b. Te whakatikatika āhuahanga, te whakatikatika ā-whakaaro, me te whakaata anō
Ka puta te whakapōturitanga āhuahanga mai i ngā koki matawai pūoko, te āhua whenua, me te nekehanga amiorangi. Ka whakamahia e te orthorectification he tauira teitei mamati (DEM) hei whakatika i ngā pānga whakawātea kia ōrite ai ngā tūranga pika ki ngā taunga tūturu. He mea nui tēnei taahiraa mō te mahere i ngā hapa, ngā kopa, ngā rohe whenua, ngā huringa mata rānei e hiahia ana kia tino tika te wāhi.
c. Te huna i ngā kapua me ngā atarangi
I roto i ngā whakaahua whatu, he arai nui ngā kapua. Ka whakamahia e ngā tikanga huna ngā roopu kounga (ngā roopu QA), ngā paepae hihi, ngā rauropi rānei pērā i te Fmask hei tautuhi i ngā kapua me ō rātou atarangi. Mō ngā rangahau huringa whenua, mō te mahere whenua rānei i ngā rohe pārūrū, he maha ngā rautaki whakakotahitanga maha-wā e whakamahia ana hei "whakakī" i ngā wāhi kua hunaia e te kapua.
d. Tātari iraira mō ngā raraunga SAR
He haruru āhua motuhake kei roto i ngā whakaahua SAR e kiia nei ko te speckle. He maha ngā tātari (Lee, Frost, Gamma-MAP) e whakamahia ana hei whakaiti i te speckle me te kore e whakakore i ngā taipitopito taha, he mea nui tēnei mō te whakamārama i ngā hanganga whenua. Me taurite te whiriwhiri tātari: ki te kaha rawa te kaha ka huna i te rārangi, ki te ngoikore rawa ka waiho he haruru.
3. Whakapai ake i te ahua mō te whakamaoritanga whenua
I roto i te mahere hanganga me te mahere whenua, ko te whāinga o te whakarei ake i te ahua he whakaatu i ētahi āhuatanga kia māmā ai te kitea.
a. Te whakakotahitanga o te roopu me te whakawhiti tae
Ka taea e ngā whakakotahitanga RGB o ngā roopu motuhake te whakaatu i ngā rerekētanga rauemi. Hei tauira, he maha ngā wā ka whai hua te whakakotahitanga o ngā roopu tata-whero me ngā roopu ngaru-poto o te whero hei wehewehe i ngā momo toka, i ngā rohe whakarerekētanga rānei. Ka whakamahia hoki ngā tikanga totoro hononga-whakarerekētanga hei whakarei ake i te rerekētanga i waenga i ngā roopu, kia kitea ai ngā rerekētanga ngawari.
b. Te whakakoi me te whakarerekētanga ā-wāhi
Mā te tātari whakawhiti-teitei, mā te ārai kore-koi rānei e whakanui ngā taha me ngā rārangi, e hono pinepine ana ki ngā rohe hapa, pakaru rānei. Hei tāpiri, mā te tātari kakano (hei tauira, GLCM—Gray Level Co-occurrence Matrix) ka āwhina i te ine i te kanorau o ngā tauira mata, he mea whai hua mō te wehewehe i ngā waeine whenua me ngā waeine whenua.
c. Te panonitanga āwhata: te ōwehenga PCA me te roopu
Ka whakaitihia e te Tātari Wāhanga Matua (PCA) te whānuitanga o ngā raraunga maha-tirohanga, ā, ka whakaatuhia ngā rerekētanga matua e pā ana ki ngā rerekētanga matawhenua. He maha ngā wā ka whakamahia ngā ōwehenga roopu i roto i te tūhuratanga kohuke nā te mea he mimiti motuhake ētahi kohuke i ngā roangaru motuhake. I roto i te matawhenua tono, ka taea e ngā ōwehenga roopu te whakarato i tētahi tohu tuatahi o ngā rohe tirohanga i mua i ngā rangahau mara, i te matawhenua taipitopito rānei.
4. Te whakarōpūtanga me te tango mōhiohio
Kia oti te whakaahua, ko te mahi e whai ake nei ko te tango pūnaha i ngā mōhiohio matawhenua.
a. Te whakarōpūtanga o te hunga e tirotirohia ana, me te hunga kāore e tirotirohia ana
Ko te whakarōpūtanga e tirotirohia ana (hei tauira, SVM, Random Forest) me whai raraunga whakangungu mai i te mara, mai i tētahi mapi tohutoro rānei. Ko te whakarōpūtanga kāore i tirotirohia (k-means, ISODATA) ka whakarōpū i ngā pika i runga i te ōritetanga o te hihi me te kore he tapanga i mua. I roto i te matawhenua, ka taea e ngā hua whakarōpūtanga te āwhina i te mahere i te hanganga o te mata, te tohatoha o te paru, ngā rohe whakarerekētanga waiariki, ngā waeine matawhenua rānei e pā ana ki ngā tukanga tectonic.
b. Te Wehewehenga me te Tātari Whakaahua e Hangai ana ki te Ahanoa (OBIA)
Ka whakarōpūhia e te OBIA ngā pika ki ngā mea i runga i te āhua me te whānuitanga o te ira, kātahi ka whakarōpūhia. He pai ake tēnei tikanga mō ngā whakaahua taumira teitei nā te mea he nui ake te hiranga o ngā hanganga matawhenua—pērā i ngā rārangi whenua, ngā pā waikura, ngā tauira rerenga wai rānei—i ngā pika takitahi.
c. Te tango i te raina
Ko ngā rārangi ā-papa he āhuatanga rārangi e whakaatu ana i ngā hapa, ngā whati, ngā hononga ā-papa rānei. Ko ngā tikanga tango ko te kimi taha (Canny, Sobel), te panonitanga Hough, me te tātari aronga. Kātahi ka taea te whakarite i ngā mahere rārangi ā-papa ki ētahi atu raraunga ā-whenua, pērā i ngā rerekētanga aukume, ngā raraunga rū whenua rānei, hei whakamārama i ngā hanganga o raro i te mata.
5. Interferometry SAR (InSAR) mō te whakarerekētanga o te mata
Ko tētahi o ngā takoha nui a te whakaahua amiorangi ki te ahupūngao whenua ko InSAR, e whakamahi ana i ngā rerekētanga āhua o ngā ngaru radar mai i ngā hopunga e rua, neke atu rānei, hei tatau i ngā huringa o te tawhiti o te mata o te amiorangi. Mā te InSAR, ka taea te mahere i ngā whakarerekētanga o te torutoru henimita ki te mirimita ki runga i ngā wāhi nui ki:
– te rerekētanga o te rū whenua me te āhua o muri i te rū whenua,
– te pikinga/te hekenga o te utu o te puia,
– te totohu o te whenua nā te tangohanga o te wai whenua,
– te pumau o te pari me ngā horo whenua.
Ko te tukatuka InSAR e uru ana ki te rēhitatanga whakaahua, te hanganga interferogram, te whakaiti i te āhua o te whenua (mā te whakamahi i te DEM), te tātari āhua, te wetewete, me te whakatikatika āhuarangi. Ka whakarei ake i te tika o ngā tikanga raupapa-wā pēnei i te PSInSAR, SBAS rānei mā te tātari i ngā whakaahua maha i roto i te wā roa.
6. Te whakaurunga ki ētahi atu raraunga ā-whenua me te whakamana mara
Kāore e tū motuhake ngā whakaahua amiorangi. Ka puta tōna uara nui ina honoa ki ētahi atu raraunga matawhenua pēnei i:
– te aukume me te kaha ā-papa hei whakatau tata i te hanganga me te mātotoru o raro i te mata,
– te rū whenua mō te āhua o te paparanga me ngā hapa,
– te matū whenua mō te manatoko i ngā whakarerekētanga,
– GPS me te whakataurite hei whakamana i ngā hua whakarerekētanga InSAR.
He mea nui tonu te manatoko mara, inā koa hei whakaū i ngā whakamaoritanga o te hanganga whenua, hei whakaū i ngā hapa hohe, me te tango tauira.
7. Ngā wero me ngā ahunga whanaketanga
Ko ētahi o ngā wero matua o te tukatuka whakaahua amiorangi i roto i te ahupūngao whenua ko te rerekētanga o te whenua, te taupoki kapua, ngā rerekētanga o ngā āhuatanga o ngā pūoko, me ngā whakaritenga tatau mō ngā huinga raraunga nui. Heoi, ko te whanaketanga o te rorohiko kapua me ngā tūāpapa pēnei i te Google Earth Engine, me ngā ahunga whakamua i roto i te ako mīhini me te ako hohonu, kei te whakateretere i te tukatuka maha-wā me te maha-pūoko. I te heke mai, ko te whakaurunga o ngā raraunga amiorangi mata, SAR, wera, me te matarohia ka whakarei ake i te kaha ki te aroturuki i ngā tukanga hihiri o te Ao i te wā tata tonu.
Te Katinga
Ko ngā tikanga tukatuka whakaahua amiorangi i roto i te matawhenua ko te tukatuka mua (te irahiko, te āhuahanga, me ngā whakatikatika tātari), te whakarei ake i te whakaahua, te whakarōpūtanga me te tango āhuatanga, me te tātari matatau pēnei i te InSAR mō te whakarerekētanga o te mata. Mēnā he huarahi tika, ka taea e te whakaahua amiorangi te noho hei taputapu tino whai hua mō te mārama ki ngā tukanga matawhenua me te matawhenua, te tautoko i te tūhuratanga rauemi, me te whakaiti i ngā āhuatanga kino. Ko te kī ki te angitu kei roto i te whiriwhiri raraunga tika, te tukatuka tupato, te whakaurunga maha-pūtake, me te manatoko mara tika.
