Table 2 Threshold values for the basic index of the evaluation indices

Natural Population Growth Rate (D₁)

P

8 ‰

Wang, 2005 [13]

Population Density (D₂)

P

81.4 person/hm²

Average value of Heilongjiang province, 2005

Per Capita Arable Land (D₃)

P

0.43 hm²/person

Eco-construction Primary Standard of Heilongjiang Province

Area Proportion of Soil and water Loss (D₄)

P

27.2 %

Target of the starting stage of eco-construction of Heilongjiang province

Fertilizer Load (D₅)

P

200 kg/hm²

Construction standards of ecological demonstration areas in Heilongjiang province

Pesticide Load (D₆)

P

4.2 kg/hm²

Average value of Heilongjiang province, 2005

Probability of Natural Disaster (D₇)

P

41.5 %

Average value of Heilongjiang province, 2005

Forestry and Grass Coverage (D₈)

N

25 %

Construction standards of ecological demonstration areas in Heilongjiang province

Soil Erosion Modulus (D₉)

P

2500 t/km² a

Soil erosion classification standard

Effective Thickness of Soil Layer (D₁₀)

P

20 cm

Zhang et al., 2006 [14]

Precipitation Rate of April~May to July~August (D₁₁)

P

39.3/337.7

Achieved from the analysis of the historical statistical data

Effective Irrigation Rate of Arable Land (D₁₂)

P

30 mm

Shu K L, 2006 [15]

Agricultural Technican Per Ten Thousand People (D₁₃)

P

4 person

China rural well-off social standards

Area Proportion of Soil and Water Loss Control (D₁₄)

N

50 %

Construction standards of ecological demonstration areas in Heilongjiang province

Per Capita Rural Net Income (D₁₅)

N

2000 RMB

Construction standards of ecological demonstration areas in Heilongjiang province

Agriculture Production Per Unit Cultivated Land (D₁₆)

N

10000 RMB/hm²

Construction standards of circular economy demonstration areas in Heilongjiang province