INDICATORS
The nomenclature of a block’s green framework
Until a quantity is named, expressed in units and tied to a source, it cannot be required — only urged. This is the technical part of the proposed standard: nine indicators in four groups, each with its data source and means of verification.
Four of the nine cannot be computed, and that is written here
Of the nine indicators, five can be computed directly today, two partially, and two not at all. The reason for each refusal is named and tied to a specific line of the register of the state of the data, rather than waved at in general terms. A nomenclature that hides its own incompleteness deceives whoever sets out to calculate with it.
Quantity
How much greenery there is. The most familiar group and the only one usually counted, which is why it feels as though there are indicators enough.
Density of trees
шт./гаComputable- What is measured
- The number of trees within the block, related to its area.
- Data source
- Field survey; provisionally, open mapping data.
- How it is verified
- Recount against the published list of tree coordinates.
Share of planted surface
%Computable- What is measured
- The area of planted surface against the area of the block.
- Data source
- Survey, openly available satellite imagery.
- How it is verified
- Re-measurement from imagery of the same date.
Provision of a view onto greenery
%Partial- What is measured
- The share of dwellings from whose windows at least three trees are visible.
- Data source
- Building geometry, window orientation, tree positions.
- How it is verified
- Visibility computed against the published block model.
- What stands in the way
- Building geometry and window orientation are incomplete in open data; a full count requires a survey.
Connectivity
Whether the greenery joins into a framework. Isolated patches form no framework: they cannot be walked through, they do not perform a climatic function, and they do not bind the territory together.
Share of connected framework
%Computable- What is measured
- The share of planted areas joined by continuous planted links, against the total planted area.
- Data source
- Geometry of the planted areas and the links between them.
- How it is verified
- Connectivity recomputed from the published geometry.
Density of breaks in the framework
шт./кмComputable- What is measured
- The number of breaks in a planted link per kilometre of its length.
- Data source
- The same geometry as for the previous indicator.
- How it is verified
- Recomputed from the published geometry.
Accessibility
Whether the greenery can be reached on foot. A hectare of planting behind a fence and a hectare within walking distance are different quantities, however equal in count.
Distance to public greenery
мComputable- What is measured
- The walking distance from the entrance to the nearest public planted area.
- Data source
- Open pedestrian network, positions of entrances.
- How it is verified
- Route recomputed against the published network.
Share of residents within walking distance
%Partial- What is measured
- The share of residents for whom the distance under the previous indicator does not exceed the set value.
- Data source
- Distribution of residents by building, block boundaries.
- How it is verified
- Recomputed given the same source data.
- What stands in the way
- Resident numbers per building are not openly available; boundaries are available with restrictions.
Durability
Whether what was counted is still there in three years. This group is what separates the proposed standard from those in force: it regulates the result, not the intention.
Survival of planting
%Not computable- What is measured
- The share of planted specimens still alive at the set date.
- Data source
- A repeat survey of the same territory.
- How it is verified
- Comparison of two published surveys.
- What stands in the way
- Requires a repeat observation after the set interval; at the first measurement it cannot be determined at all.
Change in the share of planted surface
п. п.Not computable- What is measured
- The difference in the share of planted surface between two measurements.
- Data source
- Two measurements separated by the set interval.
- How it is verified
- Subtraction of published values.
- What stands in the way
- The same: undefined at the first measurement. The indicator appears only with the second survey.
Where the threshold values come from
The basis is the rule of three quantities used in international planting practice: no fewer than three trees in view from a dwelling, a share of canopy cover for the block, and a limiting distance to public greenery. The rule sets the frame; the specific values for Russian conditions are to be established when the standard is drafted and are deliberately not given here — to set them before field testing would be to pass a supposition off as a requirement.
What will turn this into a standard
Field testing on a real block: values for all nine indicators, determined on the ground and reproduced by an outsider from published data. Until then the nomenclature remains a proposal, not a document.