我國有四成地下水�(jiān)測較�
國土資源部日前發(fā)布的《國土資源公�(bào)》顯示,全國198�(gè)地市�(jí)行政區(qū)共有4929�(gè)地下水水�(zhì)�(jiān)測點(diǎn),其中綜合評(píng)�(jià)水質(zhì)呈較差級(jí)的監(jiān)測點(diǎn)�1999�(gè),占40.6%,水�(zhì)呈極差級(jí)的監(jiān)測點(diǎn)�826�(gè),占16.8%。主要超�(biāo)組分為鐵、錳、氟化物�“三氮”(亞硝酸鹽氮、硝酸鹽氮和銨氮)、總硬度、溶解性總固體、硫酸鹽、氯化物等,�(gè)別監(jiān)測點(diǎn)存在重(類)金屬�(xiàng)目超�(biāo)�(xiàn)象�
在這些�(jiān)測點(diǎn)中,綜合�(píng)�(jià)�(jié)果為水質(zhì)呈優(yōu)良級(jí)的監(jiān)測點(diǎn)�580�(gè),占全部�(jiān)測點(diǎn)�11.8%,水�(zhì)呈良好級(jí)的監(jiān)測點(diǎn)�1348�(gè),占27.3%,水�(zhì)呈較好級(jí)的監(jiān)測點(diǎn)�176�(gè),占3.6%。據(jù)了解,其中水�(zhì)綜合變化呈穩(wěn)定趨勢的�(jiān)測點(diǎn)�2974�(gè),呈變好趨勢的監(jiān)測點(diǎn)�793�(gè),占17%;呈變差趨勢的監(jiān)測點(diǎn)�910�(gè),占19.5%。總體來看,地下水水�(zhì)綜合變化趨勢以穩(wěn)定為主,呈變好趨勢和變差趨勢的監(jiān)測點(diǎn)比例相當(dāng)�
熱水管道泵廠� |