我國(guó)有四成地下水�(jiān)�(cè)較差
�(guó)土資源部日前�(fā)布的《國(guó)土資源公�(bào)》顯�,全�(guó)198�(gè)地市�(jí)行政區(qū)共有4929�(gè)地下水水�(zhì)�(jiān)�(cè)�(diǎn),其中綜合評(píng)�(jià)水質(zhì)呈較差級(jí)的監(jiān)�(cè)�(diǎn)�1999�(gè),占40.6%,水�(zhì)呈極差級(jí)的監(jiān)�(cè)�(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�,�(gè)別監(jiān)�(cè)�(diǎn)存在重(類)金屬�(xiàng)目超�(biāo)�(xiàn)��
在這些�(jiān)�(cè)�(diǎn)�,綜合評(píng)�(jià)�(jié)果為水質(zhì)呈優(yōu)良級(jí)的監(jiān)�(cè)�(diǎn)�580�(gè),占全部�(jiān)�(cè)�(diǎn)�11.8%,水�(zhì)呈良好級(jí)的監(jiān)�(cè)�(diǎn)�1348�(gè),占27.3%,水�(zhì)呈較好級(jí)的監(jiān)�(cè)�(diǎn)�176�(gè),占3.6%。據(jù)了解,其中水�(zhì)綜合變化呈穩(wěn)定趨�(shì)的監(jiān)�(cè)�(diǎn)�2974�(gè),呈變好趨勢(shì)的監(jiān)�(cè)�(diǎn)�793�(gè),占17%;呈變差趨勢(shì)的監(jiān)�(cè)�(diǎn)�910�(gè),占19.5%??傮w來看,地下水水質(zhì)綜合變化趨勢(shì)以穩(wěn)定為�,呈變好趨勢(shì)和變差趨�(shì)的監(jiān)�(cè)�(diǎn)比例相當(dāng)�
熱水管道泵廠� |