Table 1
Description of the 70 sampling transects that were used for visibility prediction based on the forest inventory data. G is basal area, H100 the site index. A transect may extend over several forest stands.
Tabel 1. Takseertunnustele tuginevas nähtavuse simulatsioonkatses kasutatud vaatlustrasside kirjeldus neile jäävate eraldiste andmete põhjal. G on rinnaspindala, H100 on kõrgusindeks.
| Dominant species Enamuspuuliik | Age (yr) Vanus (a) | G (m2 ha−1) | H100 (m) | Count of stands Puistute arv |
|---|---|---|---|---|
| Pinus sylvestris L. | 85 (23–158) | 26 (2–45) | 24 (10–34) | 45 |
| Betula pendula Roth, B. pubescens Ehrh. | 49 (22–93) | 20 (5–33) | 28 (18–33) | 28 |
| Picea abies (L.) H. Karst. | 60 (38–117) | 24 (11–30) | 30 (23–34) | 15 |
| Alnus glutinosa (L.) Gaertn. | 58 (22–77) | 22 (9–29) | 27 (24–34) | 5 |
| Larix spp. | 33 | 24 | 40 | 1 |
| Alnus incana (L.) Moench | 20 | 14 | 30 | 1 |
Figure 1
Observed visibility and the predicted 75th percentile of visibility using FI data. Transects were measured in April–May (black) and in September (green).
Joonis 1. Vaadeldud nähtavus ja metsa takseerandmete põhjal prognoositud nähtavuse 75-protsentiil. Trasse mõõdeti kevadel (mustad sümbolid) või septembris (rohelised sümbolid).
Figure 2
Model (6), (a) as applied to 2019 springtime ALS data with parameters estimated from 2017 summer ALS data, and (b) conversely. Transects were measured in April–May (black) and in September (green).
Joonis 2. Mudel (6) a) parameetrid lähendatud 2017. aasta suve lidariandmetel ja rakendatud 2019. aasta kevadistele andmetele, b) vastupidi. Trasse mõõdeti kevadel (mustad sümbolid) või septembris (rohelised sümbolid).
Table 2
Model parameters (ALS) with RSE the model residual error and DF the number of indicated degrees of freedom. The determination coefficient R2 for the nonlinear model (3) is an estimate. Insignificant values (p > 0.05) are in italics.
Tabel 2. Mudelite parameetrid (lidarandmetest). RSE on mudeli jääkviga, DF on vabadusastmete arv. Mittelineaarse mudeli (3) determinatsioonikordaja R2 kohta on antud hinnang. Mitteolulised väärtused (p > 0.05) on kursiivis.
| Model Mudel | Data Andmed | Parameters / Parameetrid | ||||||
|---|---|---|---|---|---|---|---|---|
| a | b | c | d | RSE (m) | R2 | DF | ||
| 3 | 2017 | 2.59 | 0.023 | − | − | 28.3 | *0.64 | 97 |
| 2019 | 1.98 | 0.016 | − | − | 26.3 | *0.69 | 97 | |
| 4 | 2017 | 14.3 | 8.02 | − | − | 24.8 | 0.55 | 97 |
| 2019 | 18.5 | 8.11 | − | − | 25.1 | 0.53 | 97 | |
| 5 | 2017 | 4.59 | 6.08 | 0.362 | − | 23.9 | 0.59 | 96 |
| 2019 | 2.72 | 5.26 | 0.506 | − | 23.8 | 0.59 | 96 | |
| 6 | 2017 | 39.9 | 7.43 | 0.309 | −0.610 | 21.8 | 0.66 | 95 |
| 2019 | 28.4 | 7.73 | 0.438 | −0.655 | 21.3 | 0.67 | 95 | |
* Estimated with equation (9).
Pinus sylvestris stand, long visibility distance.
Pinus sylvestris stand, medium visibility distance.
Populus tremula L. stand, long visibility distance.
Betula pendula stand, limited visibility distance.
Young Betula pendula stand, long visibility distance.
Young mixed broadleaf decidous stand, limited visibility distance.