Damage to mangrove trees is one of them influenced by the types of tree damage. The more types of tree damage to a single mangrove tree, the worse the health level of the mangrove tree will be. This ...study aims to obtain damage index trend values and types of tree damage in the east coast mangrove forest area, East Lampung Regency. Measurement of the types of damage to mangrove trees was carried out three times using the Forest Health Monitoring (FHM) method in two FHM cluster plots for each mangrove forest area. Assessment of damage to mangrove trees uses the Damage Index formula. The results showed that the trend index values for mangrove tree damage were 9.3 and 4.5 (Resort Kuala Penet, Way Kambas National Park), 9.2 and 19.8 (Margasari, Labuhan Maringgai), and 6.2. and 9.8 (Purworejo, Pasir Sakti) with the dominant types of damage being open wounds (code 03) 343 damage, damaged foliage/shoots (code 24) 240 damage, and broken/dead (code 22) 158 damage. Thus, the trend of damage index and types of damage to mangrove trees in the east coast mangrove forest area of East Lampung Regency has increased.
•Fencing is more effective than repellent to protect tree sapling in plantations.•The effectiveness of fence is reduced by deeper snow and steeper slope.•Protection methods against deer should be ...selected depending on surrounding conditions.
Population expansion of deer and the damage to planted trees caused by them is becoming a serious conflict between deer and humans. Although there are many methods for tree protection, their effectiveness varies from case to case, and the determinant of effectiveness has rarely been clarified. We investigated the following three specific questions: 1) What factors influence forest managers' choice of protection methods? 2) What factors were important in reducing tree damage by each protection method? 3) Which of the repellents and fences was more effective in reducing tree damage? In 2018, we obtained data of plantation tree damages caused by sika deer (Cervus nippon) and tree protection methods from 1424 plantations in Japan. No protection was chosen at low deer densities, and repellents and fences were chosen at middle and high densities by forest managers. In the case of repellents, the damage rank increased with increasing deer density, tree age, and maximum snow depth, but was not affected by planted tree species (Cryptomeria japonica and Chamaecyparis obtusa). In the case of fences, the damage rank increased with increasing deer density, tree age, maximum snow depth, slope, and decreasing net height. The damage rank also increased with the usage of separable digging prevention net and the net without stainless wire. When the age of planted trees is seven, repellents can suppress the tree damage under 50% only when the deer density is below 10 deer/km2 (no snow) or 6 deer/km2 (snow depth is 16 cm). Fences can suppress tree damage below 50% when deer density was below 38 deer/km2 (snow depth: 0, slope: 35°) or 25 deer/km2 (snow depth: 16, slope: 35°). Deer protection methods should be selected according to environmental conditions such as deer density, snow depth, and slope degree in the case of our treated tree species.
•Hurricane Michael caused severe damage to planted pine stands in the Southeast U.S.•Twenty-eight variables were assessed for their accuracy in predicting lost timber volume.•Sands with dominant ...heights > 14 m, trees per acre < 600, and within 50 km of the coast.•Were the most likely to experience severe loss.•Stands thinned within the last 10 yrs. had slightly higher damage probability.•Probability of damage increased in areas of higher topographic wetness.
Catastrophic wind disturbances can greatly impact the economic and ecological values of working forests worldwide. For example, Hurricane Michael caused severe economic damage in 2018 to commercial loblolly (Pinus taeda L.) and slash (Pinus elliotti Engelm.) planted pine stands in the southeastern U.S. This project examined the relative importance of prior management activities, stand characteristics, and soil and terrain attributes in predicting stand damage from a catastrophic hurricane event. We assembled data from land managers in coastal Alabama, the Florida panhandle, and South Georgia, on percent loss of trees after Hurricane Michael in over 400 stands, along with stand management history, and stand characteristics. Digital elevation models were utilized to determine terrain and hydrological characteristics of the landscape including aspect, channel distance, elevation, LS factor (slope and length steepness factor), slope angle, slope position, terrain ruggedness index, topographic wetness index, and wind exposition index. Random forest models were used to determine the relative accuracy of windspeed, management history, stand characteristics, and soil and terrain attributes in predicting stand damage. From the variables evaluated, stand density (as described by trees per acre), and tree height (as described by the average height of dominant and co-dominant trees) were among the most influential characteristics in predicting damage severity along with windspeed and linear distance from the coast. Stands with dominant heights > 14 m, trees per acre < 600 (trees per hectare < 1,483), and within 50 km of the coast were the most likely to experience severe damage. Topographic wetness index was the most influential terrain characteristic, with sands in wetter soils more likely to experience more severe damage. Recently thinned stands were slightly more vulnerable to severe damage. Results from this study can be used to develop vulnerability profiles for commercial pine stands in the coastal plain region in the southern U.S. region.
Damages to residual trees caused by felling operation were assessed in the stands of a Caspian hardwood forest. Following the felling operation, a field survey was done to collect data of all ...residual trees (species, DBH, height) and of tree wounds (size class, location, intensity of damage). Different harvesting intensities were studied, and treatments were replicated three times. The results showed that the treatment with the medium and high harvest intensity was found to cause the highest percentage of damage and the largest stem wounds. It is concluded that harvesting intensity should be limited to 3 trees/ha during each harvesting operation to reduce the extent of tree damage and thus future financial loss.
U radu se procjenjuju oštećenja preostalih stabala uzrokovanih pridobivanjem drva u kaspijskim bjelogoričnim sastojinama. Nakon sječe provedeno je terensko istraživanje radi prikupljanja podataka o svim preostalim stablima (vrste, prsni promjer, visina) te o oštećenjima stabala (veličina, mjesto, intenzitet oštećenja). Promatrani su različiti intenziteti sječe, a postupci su ponovljeni tri puta. Prema rezultatima sadašnjih istraživanja 97 % ogrebotina, oguljotina i drugih oštećenja događa se na prva 1,3 m debla (Nikooy 2007, Behjou 2014). Druga su istraživanja pokazala da će otvorena oštećenja s > 100 cm2 izložene bjeljike vjerojatno izazvati trulež (Hesterberg 1957, Lavallee i Lortie 1968). Za kaspijske šume Naghdi (2004) izvještava da 1,4 % preostalih stabala po hektaru (≥10 cm) zadobiva neku vrstu oštećenja, a na 0,6 % stabala drvo je izloženo oštećenju. Nikooy i dr. (2007) utvrdili su da je 1,9% preostalih stabala po hektaru (≥10 cm) zadobilo neku vrstu oštećenja, pri čemu se prosječna gustoća sastojina u
tim istraživanjima kretala od 160 do 170 stabala po hektaru slično kao u
ovom istraživanju. Istraživanja u drugim zemljama u kojima su primjenjivani modeli vjerojatnosti oštećivanja pokazala su slične rezultate s obzirom na udaljenost od traktorske vlake (Nichols i dr. 1994). Nichols i dr. (1994) također su izvijestili da se porastom temeljnice sastojine povećava vjerojatnost oštećivanja, što je donekle slično rezultatima ovoga istraživanja. Dodatno, ukupno oštećivanje sastojine pozitivno korelira s brojem preostalih stabala po hektaru (Holmes i dr. 2002). Slično se utvrdilo i ovim istraživanjem. Oštećenja veća od 100 cm2, u usporedbi s manjim ranama, manje će se vjerojatno zatvoriti 10 godina nakon sječe (Smith i dr. 1994). Velika oštećenja također imaju veću vjerojatnost za razvoj truleži, a ponegdje se njihov obujam pogoršava i do 20 godina nakon ozljede (Hesterberg 1957, Lavallee
i Lortie 1968). Rezultati istraživanja prikazanih u radu pokazuju da postupci sa srednjim i visokim intenzitetom sječe uzrokuju najviši postotak šteta te najveća oštećenja na stablima. Zaključuje se da bi intenzitet sječe trebao biti ograničen na 3 stabla/ha tijekom svake operacije pridobivanja drva kako bi se smanjio opseg oštećivanja stabala, a time i budući financijski gubici.
•Atmospheric CO2 and wind data is considered to improve wind damage risk modeling.•Trees' fragility to wind damage is increasing with climate change.•Risk analysis presented of a 30-year-old birch ...tree in 1990, 2020, 2050, and 2080.•The wind speed required to damage trees is shown to decrease as time advances.•Despite greater load capacity, fragility increases due to rising tree size.
Trees provide numerous benefits to communities, but pose a risk when they are damaged. The likelihood that trees will be damaged in a windstorm is increasing due to climate change, as wind trends are changing as the climate warms, and rising atmospheric CO2 concentrations could alter the resistance of trees to wind damage.
To address these concerns, we created a tree damage model that integrates results from a meta-analysis about the effects of elevated CO2 concentrations on tree growth and an analysis of the return period of damaging winds in Toronto, Canada from 1990 to 2080. This joint analysis is applied for a simulated silver birch (Betula pendula) tree. Our model predicts that by 2080, due both to a high CO2-induced decrease in tree resilience and an increased likelihood of more frequent and intense windstorms, damaging windstorms will occur about twice as frequently as they do today.
•The ice storm damaged over 90% of trees in the overstory but only 30% in the understory.•The crown loss was the primary damage type, but snapped boles caused the most mortality.•Evergreen ...broadleaves were more vulnerable to ice storm damage than other lifeforms.•The most ice storm-tolerant pine (loblolly pine) has the most northerly distribution.•Periodic ice storms may affect the abundance and distribution of tree species.
The unique terrain, geography, and climate patterns of the eastern United States encourage periodic occurrences of catastrophic ice storms capable of large-scale damage or destruction of forests. However, the pervasive and persistent effects of these glaze events on regional forest distribution and composition have rarely been studied. In the southeastern US, ice storm frequency and intensity increase with increasing latitude and along the complex gradients from the coast (low, flat, sediment controlled and temperature moderated near the ocean) to the interior (high, rugged, bedrock controlled, distant from warming ocean). To investigate the potential influence of this disturbance gradient on regional forest composition, we studied the differential responses of trees (canopy position, lifeform group, and species group) to a particularly severe ice storm. Our results indicated that tree mortality and damage (canopy damage, bent bole, snapped bole, and uprooted) varied significantly between overstory and understory trees, and among species and lifeform groups. Overstory trees were more prone to glaze damage than understory trees, and evergreen broadleaf species were the most susceptible to glaze damage, while deciduous species were the least susceptible. Among the pine species studied, slash pine (Pinus elliottii Engelm.) and longleaf pine (P. palustris Mill.) suffered more severe damage and mortality than loblolly pine (P. taeda L.). Further, ice damage was correlated with distribution-based differences in injury susceptibility among pine and deciduous tree species. The most ice storm-tolerant pine species, loblolly pine, had the most northerly distribution (39.51°N), while the least resistant species were those with more southerly distribution (e.g., 33.29°N for slash pine). These results support hypotheses that the distributions of evergreen tree species are regulated by periodic catastrophic ice storms. Therefore, predicting future distributions of tree species in response to climate change should consider the role of ice storms in shaping the forest composition.
Community forest management usually applies agroforestry patterns because it is felt that they will provide more social, economic and ecological benefits. Optimal yields will be obtained if the ...community forest is healthy. It becomes an effort to prevent forest destruction at a low level through forest health, thereby ensuring the functions and benefits of managed community forests. One indicator of forest health is the amount of tree damage that occurs and the condition of the crown. The purpose of this report is to provide an overview of the vitality condition of agroforestry-patterned community forests and to serve as a reference for future decisions about the maintenance and development of these forests. This study was conducted in a community forest owned by members of the combined forest farmer groups Satria Rimba, Way Khilau District, Pesawaran Regency, Lampung Province, Indonesia. The method used is the Assessment of Forest Health Monitoring (FHM) method. The parameters of the vitality condition assessment consist of tree damage and crown condition. This study provides results that show there are 14 types of tree damage that attacked the trees that made up stands in community forests. The most common types of damage occurred based on the percentage of incidents, namely damaged leaves (25.29%), broken branches (24.41%) and open wounds (23.34%). assessment for damage to the tree based on the CLI value, namely in the high category (clusters 2, 3); moderate category (clusters 1, 5, 6); and low category (clusters 4, 7). Assessment of the crown condition based on the VCR value, namely in the categories of ‘high’ (clusters 4, 5, 6), ‘moderate’ (clusters 2, 7) and ‘low’ (clusters 1, 3).
Summary
The relative importance of tree mortality risk factors remains unknown, especially in diverse tropical forests where species may vary widely in their responses to particular conditions.
We ...present a new framework for quantifying the importance of mortality risk factors and apply it to compare 19 risks on 31 203 trees (1977 species) in 14 one‐year periods in six tropical forests. We defined a condition as a risk factor for a species if it was associated with at least a doubling of mortality rate in univariate analyses. For each risk, we estimated prevalence (frequency), lethality (difference in mortality between trees with and without the risk) and impact (‘excess mortality’ associated with the risk, relative to stand‐level mortality).
The most impactful risk factors were light limitation and crown/trunk loss; the most prevalent were light limitation and small size; the most lethal were leaf damage and wounds. Modes of death (standing, broken and uprooted) had limited links with previous conditions and mortality risk factors.
We provide the first ranking of importance of tree‐level mortality risk factors in tropical forests. Future research should focus on the links between these risks, their climatic drivers and the physiological processes to enable mechanistic predictions of future tree mortality.
Remotely controlled, unmanned aerial vehicles (UAVs) promise to be of high potential for a variety of applications in ecological and behavioural research. Off‐the‐shelf solutions have recently become ...available for civil use at steeply decreasing costs. In this study, we explored the utility of an UAV equipped with an on‐board camera (14 megapixel photo and 1920 × 1080 pixel video resolution) in assessing the breeding status, offspring number and age of a canopy‐breeding bird species, the hooded crow Corvus corone cornix. We further quantified performance and potential time savings using the UAV versus inspection with alternative approaches (optical instruments, camera on a telescopic rod, tree climbing). Nesting status, number and approximate age of nestlings could be assessed with good success in all 24 attempts using the UAV. Eighty‐five percent of the time required for inspection by climbing could be saved. Disturbance was moderate and lower than caused by climbing or using a camera on a telescopic rod. Additionally, UAV usage avoided tree damage and circumvented health risks associated with tree‐climbing.
Repairing the micro-scale damage of insulating materials under a strong electric field has long been a highly desired but challenging task. Among all kinds of damage, water tree damage in the ...insulating materials of electrical equipment and electronic devices working in humid environments has long been considered irreparable. The main challenge is that residual water prevents the healing agent from filling the water tree branch channel. To solve this problem, this work reports a magnetically targeted, water-triggered, self-healing microcapsule (MTWTSH-MC) that makes a breakthrough against water tree damage based on microfluidic techniques. Targeted microcapsules driven by a directional magnetic field are concentrated to the vulnerable area of the insulating materials, exerting very limited effects on the dielectric. When damage breaks the microcapsules, the healing agent releases and quickly fills the damage channel and then reacts with water in the air or in the branch channel of the water tree, achieving solidification of the healing agent and self-healing of the damage channels. In this way, we can realize self-perception, self-triggering, and self-healing for both mechanical damage and water tree damage in insulation materials without any external stimulation.
PDF
