Baseline Survey

What we know so far through our investigations.

We have completed a multi-dimensional baseline study covering climate history, land-use change, vegetation systems, hydrogeology, and stakeholder interviews.
This work has provided a preliminary outline of ecological succession and shifting human–land relationships in Sha Lo Tung since the decline of agriculture, laying a critical foundation for future conservation planning and collaborative governance.

Historical climate analysis

Historical Climate Analysis:

In 1992, Sha Lo Tung's Normalised Difference Vegetation Index (NDVI) reached a historical low, indicating dense surface water distribution and a stable, healthy wetland ecosystem at the time. However, NDVI has gradually increased since then, reflecting expanding vegetation cover and an ecological shift toward a climatic climax community.
The sharp rise in both potential evapotranspiration (PET) and actual evapotranspiration (AET) partly reflects the impact of climate warming, which has led to the gradual drying of water bodies. This, in turn, has enabled the encroachment of non-wetland plant species, further contributing to the rising NDVI.
If this warming trend persists, Sha Lo Tung’s wetland may evolve into an “unnatural” state—requiring external water inputs to sustain its wetland characteristics. Overall, the early 1990s marked a critical turning point in the structural transformation of the area’s ecosystem.