

def water_temperature()->str:
    """surface water temperature in degrees celcius"""
    return "water_temp_C"


def electrical_conductivity()->str:
    """electrical conductivity of surface water samples in microsiemens per centimeter"""
    return "electrical_conductivity_uS/cm"


def ph()->str:
    """pH of surface water samples"""
    return "pH"


def o2c()->str:
    """oxygen concentration in surface water samples"""
    return "o2c_mg/l"

def tot_N()->str:
    """Total nitrogen concentration in surface water samples"""
    return "tot_N_mg/l"

def tot_P()->str:
    """Total phosphorus concentration in surface water samples"""
    return "tot_P_mg/l"

def toc()->str:
    """Total organic carbon concentration in surface water samples"""
    return "toc_mg/l"

def tss()->str:
    """Total suspended solids concentration in surface water samples"""
    return "tss_mg/l"

def doc()->str:
    """Dissolved organic carbon concentration in surface water samples"""
    return "doc_mg/l"

def nitrate()->str:
    """Nitrate (NO3_N) concentration in surface water samples"""
    return "nitrate_mg/l"