Table 1 FSTI system.

From: GeoDetector analysis of spatio-temporal patterns and driving mechanisms of farmland spatial transition within 897 counties in the Yangtze River Economic Belt, China

Subsystem

Indicators

Calculation formula

Indicator significance

Scale

transition

Average farmland area per laborer

\({ {LF}}=A/L\)

Scale of mechanized farming within farmland

Average plot size

\({ {MPS}}=A/N\)

Size of land parcels in farmland

Patch density index

\({ {PD}}=N/A\)

Degree of farmland fragmentation

Regularization transition

Farmland edge density

\({ {ED}}=E/A\times {10}^{6}\)

Degree of fragmentation of farmland patches by boundaries

Farmland patch shape index

\({{SHAPE}}\_{{MN}}=\frac{\mathop{\sum }\limits_{i=1}^{m}\mathop{\sum }\limits_{j=1}^{n}\left(\frac{0.25{{{p}}}_{{{ij}}}}{\sqrt{{\alpha }_{{{ij}}}}}\right)}{N}\)

Level of complexity of farmland patch shapes compared to an equivalent-sized square

Average patch fractal dimension index

\({ {FRAC}}\_{{MN}}=\frac{\mathop{\sum }\nolimits_{{i}=1}^{{m}}\mathop{\sum }\nolimits_{{j}=1}^{{n}}\left(\frac{2\,{ln}(0.25{{p}}_{{ij}})}{{ln}\,{\alpha }_{{ij}}}\right)}{N}\)

Complexity of patch boundaries

Agglomeration transition

Average nearest neighbor distance index

\({ {MNN}}=\mathop{\sum }\limits_{{i}=1}^{{m}}{h}_{i}/N\text{'}\)

Dispersal of farmland patches in distribution

Aggregation index

\({ {AI}}=\left[\mathop{\sum }\limits_{i=1}^{m}\left(\frac{{p}_{ij}}{{\rm{max}}{p}_{ij}}\right){p}_{i}\right]\times 100\)

Degree of spatial clustering of farmland patches

Contagion index

\({ {CONTAG}}=\left[1+\mathop{\sum }\limits_{i=1}^{m}\mathop{\sum }\limits_{{j}=1}^{n}\left(\frac{{p}_{ij}\,\mathrm{ln}\,{p}_{ij}}{2\,\mathrm{ln}\,m}\right)\right]\times 100\)

Aggregation and diffusion trends of farmland patches

Patch cohesion index

\({ {COHESION}}=\left[1-\frac{\mathop{\sum }\nolimits_{j=1}^{{n}}{p}_{ij}}{\mathop{\sum }\nolimits_{j=1}^{n}{p}_{ij}\sqrt{{\alpha }_{ij}}}\right]\times {\left(1-\frac{1}{\sqrt{A}}\right)}^{-1}\times 100\)

Indicators of spatial connectivity in farmland landscape

Specialization transition

Simpson dominance index extension

\({ {SDI}}=\sum {q}_{{k}}^{2}\)

Regional crop dominance

Shannon evenness index extension

\({ {SHEI}}=\frac{-\mathop{\sum }\nolimits_{k=1}^{z}({q}_{k}\times \,{\mathrm{ln}}\,{q}_{k})}{{\mathrm{ln}}\,{z}}\)

Level of specialization in regional crops