{"id":132,"count":1,"description":"M\u00f4i tr\u01b0\u1eddng nu\u00f4i tr\u1ed3ng th\u1ee7y s\u1ea3n - t\u00f4m l\u00e0 y\u1ebfu t\u1ed1 \u0111\u01b0\u1ee3c quan t\u00e2m \u0111\u1ea7u ti\u00ean khi b\u1eaft tay v\u00e0o vi\u1ec7c nu\u00f4i tr\u1ed3ng t\u00f4m gi\u1ed1ng. Ng\u01b0\u1eddi nu\u00f4i c\u1ea7n \u0111i\u1ec1u ch\u1ec9nh c\u00e1c y\u1ebfu t\u1ed1 m\u00f4i tr\u01b0\u1eddng ph\u00f9 h\u1ee3p v\u1edbi t\u00f4m \u0111\u1ec3 ch\u00fang th\u00edch nghi c\u0169ng nh\u01b0 ph\u00e1t tri\u1ec3n h\u01a1n. Nh\u1ea5t l\u00e0 v\u1ea5n v\u1ec1 \u00f4 nhi\u1ec5m m\u00f4i tr\u01b0\u1eddng r\u1ea5t c\u1ea7n \u0111\u01b0\u1ee3c quan t\u00e2m \u0111\u1ec3 x\u1eed l\u00fd \u0111\u00fang c\u00e1ch, tr\u00e1nh g\u00e2y ra nh\u1eefng h\u1eadu qu\u1ea3 kh\u00f4ng t\u1ed1t v\u00e0 \u1ea3nh h\u01b0\u1edfng \u0111\u1ebfn vi\u1ec7c nu\u00f4i tr\u1ed3ng t\u00f4m.<\/strong>\r\n

T\u00ecm hi\u1ec3u c\u00e1c y\u1ebfu t\u1ed1 c\u1ee7a m\u00f4i tr\u01b0\u1eddng nu\u00f4i tr\u1ed3ng thu\u1ef7 s\u1ea3n- t\u00f4m<\/h2>\r\nC\u00f3 nhi\u1ec1u y\u1ebfu t\u1ed1 li\u00ean quan \u0111\u1ebfn m\u00f4i tr\u01b0\u1eddng nu\u00f4i tr\u1ed3ng thu\u1ef7 s\u1ea3n- t\u00f4m c\u1ea7n \u0111\u01b0\u1ee3c l\u01b0u \u00fd nh\u01b0: nhi\u1ec7t \u0111\u1ed9, oxy h\u00f2a tan, \u0111\u1ed9 pH, m\u00e0u n\u01b0\u1edbc, \u0111\u1ed9 m\u1eb7n,...\r\n

Nhi\u1ec7t \u0111\u1ed9<\/h3>\r\nT\u00f4m thu\u1ed9c lo\u00e0i m\u00e1u l\u1ea1nh, thay \u0111\u1ed5i nhi\u1ec7t \u0111\u1ed9 theo m\u00f4i tr\u01b0\u1eddng b\u00ean ngo\u00e0i. Nhi\u1ec7t \u0111\u1ed9 c\u00f3 \u1ea3nh h\u01b0\u1edfng t\u1edbi s\u1ef1 h\u00f4 h\u1ea5p, ti\u00eau th\u1ee5 th\u1ee9c \u0103n, \u0111\u1ed3ng ho\u00e1 th\u1ee9c \u0103n, mi\u1ec5n nhi\u1ec5m \u0111\u1ed1i v\u1edbi b\u1ec7nh t\u1eadt, s\u1ef1 t\u0103ng tr\u01b0\u1edfng,... c\u1ee7a ch\u00fang.\r\n\r\nV\u00ed d\u1ee5 nhi\u1ec7t \u0111\u1ed9 th\u00edch h\u1ee3p cho t\u00f4m s\u00fa l\u00e0 kho\u1ea3ng 28-30 \u0111\u1ed9 C, t\u00f4m th\u1ebb ch\u00e2n tr\u1eafng th\u00ec th\u00edch h\u1ee3p v\u1edbi nhi\u1ec7t \u0111\u1ed9 23-30 \u0111\u1ed9 C,...\r\n

\u0110\u1ed9 pH<\/h3>\r\nTrong vi\u1ec7c nu\u00f4i tr\u1ed3ng th\u1ee7y s\u1ea3n th\u00ec \u0111\u1ed9 pH m\u00f4i tr\u01b0\u1eddng n\u01b0\u1edbc thay \u0111\u1ed5i s\u1ebd \u1ea3nh h\u01b0\u1edfng \u0111\u1ebfn c\u00e1c y\u1ebfu t\u1ed1 l\u00fd, h\u00f3a, sinh c\u1ee7a m\u00f4i tr\u01b0\u1eddng v\u00e0 s\u1ee9c kh\u1ecfe c\u1ee7a th\u1ee7y s\u1ea3n. Nh\u01b0 l\u00e0 \u0111\u1ed9 pH th\u00edch h\u1ee3p cho n\u01b0\u1edbc trong ao h\u1ed3 nu\u00f4i t\u00f4m s\u00fa l\u00e0 pH = 7,2 - 8,8. N\u1ebfu \u0111\u1ed9 pH cao hay th\u1ea5p k\u00e9o d\u00e0i s\u1ebd l\u00e0m t\u00f4m ch\u1eadm t\u0103ng tr\u01b0\u1edfng, c\u00f2i c\u1ecdc, d\u1ec5 nhi\u1ec5m b\u1ec7nh, hao h\u1ee5t.\r\n

Oxy h\u00f2a tan<\/h3>\r\nOxy h\u00f2a tan l\u00e0 1 y\u1ebfu t\u1ed1 quan tr\u1ecdng, n\u1ebfu Oxy h\u00f2a tan th\u1ea5p c\u00f3 th\u1ec3 l\u00e0m t\u00f4m ch\u1ebft. \u1ede trong n\u01b0\u1edbc n\u1ed3ng \u0111\u1ed9 oxy h\u00f2a tan c\u1ea7n thi\u1ebft cho t\u00f4m h\u00f4 h\u1ea5p l\u00e0 5ppm. Oxy ho\u00e0 tan s\u1ebd gi\u1ea3m khi nhi\u1ec7t \u0111\u1ed9 v\u00e0 \u0111\u1ed9 m\u1eb7n gi\u1ea3m.\r\n

G\u00e2y m\u00e0u n\u01b0\u1edbc<\/h3>\r\nM\u00e0u n\u01b0\u1edbc c\u1ee7a m\u00f4i tr\u01b0\u1eddng nu\u00f4i tr\u1ed3ng t\u00f4m r\u1ea5t quan tr\u1ecdng. C\u00f3 m\u00e0u n\u01b0\u1edbc l\u1ee3i cho t\u00f4m nh\u01b0ng c\u0169ng c\u00f3 m\u00e0u n\u01b0\u1edbc l\u1ea1i g\u00e2y h\u1ea1i cho t\u00f4m. V\u00ec v\u1eady ng\u01b0\u1eddi nu\u00f4i t\u00f4m c\u1ea7n n\u1eafm v\u1eefng quy lu\u1eadt thay \u0111\u1ed5i m\u00e0u n\u01b0\u1edbc \u0111\u1ec3 c\u00f3 c\u00e1ch x\u1eed l\u00fd hi\u1ec7u qu\u1ea3. B\u1ea3n ch\u1ea5t c\u1ee7a m\u00e0u n\u01b0\u1edbc \u0111\u01b0\u1ee3c \u0111\u1ecbnh l\u01b0\u1ee3ng b\u1eb1ng h\u00e0m l\u01b0\u1ee3ng c\u00e1c ch\u1ea5t h\u1eefu c\u01a1 v\u00e0 v\u00f4 c\u01a1 ch\u1ee9a trong n\u01b0\u1edbc.\r\n\r\nC\u00e1c h\u1ee3p ch\u1ea5t v\u00f4 c\u01a1 bao g\u1ed3m ch\u1ea5t kh\u00f4ng h\u00f2a tan v\u00e0 h\u00f2a tan. C\u00f2n c\u00e1c ch\u1ea5t h\u1eefu c\u01a1 bao g\u1ed3m c\u00e1c sinh v\u1eadt ph\u00f9 du, th\u1ef1c v\u1eadt \u0111\u00e1y, \u0111\u1ed9ng v\u1eadt nguy\u00ean sinh. \u0110\u1eb7c bi\u1ec7t, s\u1eed d\u1ee5ng nh\u1eefng ch\u1ebf ph\u1ea9m sinh h\u1ecdc \u0111\u1ec3 th\u1ef1c hi\u1ec7n l\u00e0 vi\u1ec7c kh\u00e1 hi\u1ec7u qu\u1ea3. B\u1edfi v\u00ec v\u1eeba l\u00e0m cho n\u01b0\u1edbc ao nu\u00f4i t\u00f4m t\u1ed1t h\u01a1n, v\u1eeba l\u00e0m s\u1ea1ch n\u01b0\u1edbc, gi\u1ea3m BOD, COD, ph\u00f2ng b\u1ec7nh v\u00e0 k\u00edch th\u00edch t\u00f4m sinh tr\u01b0\u1edfng.\r\n

\u0110\u1ed9 \u0111\u1ee5c c\u1ee7a n\u01b0\u1edbc<\/h3>\r\n\u0110\u1ed9 \u0111\u1ee5c c\u1ee7a n\u01b0\u1edbc \u0111o b\u1eb1ng \u0111\u0129a Secchi. \u0110\u1ed9 \u0111\u1ee5c c\u1ee7a n\u01b0\u1edbc th\u00edch h\u1ee3p nh\u1ea5t cho vi\u1ec7c nu\u00f4i t\u00f4m l\u00e0 khi b\u1ea1n nh\u00ecn \u0111\u0129a Secchi th\u1ea5y \u0111\u01b0\u1ee3c \u1edf \u0111\u1ed9 s\u00e2u kho\u1ea3ng 25-40cm.\r\n\r\nN\u1ebfu \u0111\u0129a Secchi nh\u00ecn th\u1ea5y \u0111\u01b0\u1ee3c \u1edf \u0111\u1ed9 s\u00e2u 20-30cm th\u00ec n\u01b0\u1edbc b\u1eaft \u0111\u1ea7u \u0111\u1ee5c, n\u00ean gi\u1eef pH bu\u1ed5i s\u00e1ng < 8.0 v\u00e0 thay b\u1edbt n\u01b0\u1edbc.\r\n\r\nN\u1ebfu \u0111\u0129a Secchi nh\u00ecn th\u1ea5y \u0111\u01b0\u1ee3c \u1edf \u0111\u1ed9 s\u00e2u < 20cm: n\u01b0\u1edbc qu\u00e1 \u0111\u1ee5c, n\u00ean thay n\u01b0\u1edbc v\u00e0 d\u00f9ng v\u00f4i ho\u1eb7c \u0111olomit 150-300kg\/ha \u0111\u1ec3 l\u1eafng b\u1edbt b\u00f9n v\u00e0 t\u1ea3o, nh\u1ea5t l\u00e0 v\u00e0o m\u00f9a m\u01b0a.\r\n\r\nN\u1ebfu \u0111\u0129a Secchi nh\u00ecn th\u1ea5y \u0111\u01b0\u1ee3c \u1edf \u0111\u1ed9 s\u00e2u > 60cm: n\u01b0\u1edbc qu\u00e1 trong, n\u00ean g\u00e2y l\u1ea1i m\u00e0u n\u01b0\u1edbc v\u00e0 c\u00f3 th\u1ec3 k\u1ebft h\u1ee3p d\u00f9ng men vi sinh \u0111\u1ec3 th\u00fac cho m\u00e0u n\u01b0\u1edbc l\u00ean nhanh h\u01a1n v\u00e0 \u1ed5n \u0111\u1ecbnh.\r\n

\r\nNguy\u00ean nh\u00e2n n\u00e0o \u00f4 nhi\u1ec5m ngu\u1ed3n n\u01b0\u1edbc ao t\u00f4m?<\/h2>\r\nC\u00f3 nhi\u1ec1u nguy\u00ean nh\u00e2n g\u00e2y \u00f4 nhi\u1ec5m ngu\u1ed3n n\u01b0\u1edbc - m\u00f4i tr\u01b0\u1eddng nu\u00f4i tr\u1ed3ng t\u00f4m, nh\u01b0ng ph\u1ea7n l\u1edbn l\u00e0 do t\u00e1c \u0111\u1ed9ng c\u1ee7a con ng\u01b0\u1eddi t\u1ea1o ra. \u0110\u00f3 ch\u00ednh l\u00e0 ngu\u1ed3n th\u1ee9c \u0103n d\u01b0 th\u1eeba t\u00edch t\u1ee5 l\u1ea1i d\u01b0\u1edbi \u0111\u00e1y ao nu\u00f4i v\u00e0 th\u1ea3i ra m\u00f4i tr\u01b0\u1eddng b\u00ean ngo\u00e0i m\u00e0 kh\u00f4ng \u0111\u01b0\u1ee3c x\u1eed l\u00fd tri\u1ec7t \u0111\u1ec3.\r\n\r\nPh\u1ea7n l\u1edbn c\u00e1c lo\u1ea1i th\u1ee9c \u0103n v\u00e0 h\u1ee3p ch\u1ea5t d\u01b0 th\u1eeba t\u00edch t\u1ee5 d\u01b0\u1edbi \u0111\u00e1y ao g\u00e2y \u00f4 nhi\u1ec5m m\u00f4i tr\u01b0\u1eddng n\u01b0\u1edbc tr\u1ea7m tr\u1ecdng, t\u1ea1o \u0111i\u1ec1u ki\u1ec7n thu\u1eadn l\u1ee3i cho m\u1ea7m b\u1ec7nh sinh s\u00f4i v\u00e0 ph\u00e1t tri\u1ec3n.\r\n\r\nNgo\u00e0i ra, trong n\u01b0\u1edbc nu\u00f4i t\u00f4m c\u00f2n ch\u1ee9a d\u01b0 l\u01b0\u1ee3ng c\u00e1c lo\u1ea1i ch\u1ea5t kh\u00e1ng sinh, h\u00f3a ch\u1ea5t, thu\u1ed1c tr\u1ecb b\u1ec7nh t\u00f4m,\u2026 \u0111\u01b0\u1ee3c th\u1ea3i tr\u1ef1c ti\u1ebfp ra m\u00f4i tr\u01b0\u1eddng b\u00ean ngo\u00e0i. V\u00e0 ch\u00fang \u0111\u00e3 mang theo m\u1ed9t l\u01b0\u1ee3ng l\u1edbn h\u1ee3p ch\u1ea5t nit\u01a1 photpho, c\u00e1c ch\u1ea5t dinh d\u01b0\u1ee1ng c\u00f3 l\u1ee3i cho s\u1ef1 ph\u00e1t tri\u1ec3n c\u1ee7a c\u00e1c vi khu\u1ea9n g\u00e2y h\u1ea1i.\r\n\r\nM\u1ed9t s\u1ed1 nguy\u00ean nh\u00e2n \u00f4 nhi\u1ec5m n\u01b0\u1edbc ao t\u00f4m kh\u00e1c nh\u01b0 l\u00e0:\r\n