土壤湿度反演alpha近似模型代码

以下是一个简单的土壤湿度反演alpha近似模型的 Python 代码示例：

import math

def alpha_approximation(theta, theta_sat, theta_res, alpha):
    """
    Computes the soil moisture content given the soil moisture potential using the alpha approximation model.

    Parameters:
    theta (float): soil moisture content
    theta_sat (float): soil moisture content at saturation
    theta_res (float): residual soil moisture content
    alpha (float): inverse air entry value

    Returns:
    float: soil moisture potential
    """
    return theta / theta_sat + alpha * math.log10(theta / theta_res)

def inverse_alpha_approximation(psi, theta_sat, theta_res, alpha):
    """
    Computes the soil moisture content given the soil moisture potential using the inverse alpha approximation model.

    Parameters:
    psi (float): soil moisture potential
    theta_sat (float): soil moisture content at saturation
    theta_res (float): residual soil moisture content
    alpha (float): inverse air entry value

    Returns:
    float: soil moisture content
    """
    return theta_res * math.pow(psi / alpha, -1 / alpha) + theta_res

# Example usage
theta_sat = 0.5
theta_res = 0.1
alpha = 0.01

# Compute soil moisture potential for a given soil moisture content
theta = 0.3
psi = alpha_approximation(theta, theta_sat, theta_res, alpha)
print(f"theta = {theta}, psi = {psi}")

# Compute soil moisture content for a given soil moisture potential
psi = -100
theta = inverse_alpha_approximation(psi, theta_sat, theta_res, alpha)
print(f"psi = {psi}, theta = {theta}")

在这个示例代码中，`alpha_approximation` 函数计算给定土壤湿度的土壤湿度势，而 `inverse_alpha_approximation` 函数计算给定土壤湿度势的土壤湿度。这个函数需要一些输入参数，包括土壤湿度饱和度、残余土壤湿度饱和度和逆空气入渗值。在这个例子中，我们使用了一些预设值，你可以根据实际情况进行相应的调整。