Analysis of environmental damage and environmental economic valuation on tropical rain forest destruction in Simalungun Regency, North Sumatera Province, Indonesia

Tropical rain forests in Simalungun Regency, North Sumatra Province, Indonesia have experienced environmental damage due to illegal logging. Illegal logging activities can effect to environmental damage as well as environmental economic losses. This study aimed to analyze soil and environmental damage as well as to assess economic loss of environmental damage due to illegal logging activities in tropical rain forests in Simalungun Regency, North Sumatra Province Indonesia. The method of taking samples and analyzing environmental damage were conducted by purposive sampling. Data from laboratory tests of soil physical, chemical and biological properties were analyzed by statistical tests. The economic valuation method of environmental damage used the  Permen LH No. 13 year of 2011, Republic of  Indonesian. Illegal logging activities caused environmental damage in tropical rain forests (covering 45.65 ha). Illegal logging had a significant effects toward the bulk density increase, as well as  the C-organic decrease. In other hand Illegal logging had a significant effects on sand fraction, total microorganisms, and soil respiration. Based on the environmental economic valuation, the economic loss due to illegal logging on tropical rain forests amounting to IDR 319,799,679,000 ($ 22,842,834.21)

Deer and reforestation in the Pacific Northwest

Deer and reforestation interact mainly during regeneration after wildfire or logging. In interior forests, browsing by mule deer often damages conifer seedlings planted on winter or transitional ranges. In the Douglas-fir region, numbers of blacktailed deer increase dramatically after forests are logged or burned, in response to improved forage supplies. Here, browsing on planted stock in clearcuts lowers forest productivity by reducing growth rates and occasionally contributes to plantation failures. Browsing damage can be controlled by fences or cages, but costs are prohibitive. Amelioration of damage by black-tailed deer could be achieved through long-range planning for concurrent deer and timber harvests, with hunting pressure directed to areas where logging promotes more deer. Thus, more deer can be made available to hunters and browsing damage to reforestation lessened. Such programs would require complete cooperation among resource managers and an intensive, well-planned effort to sell them to both customers and critics

Improved timber harvest techniques maintain biodiversity in tropical forests

Tropical forests are selectively logged at 20 times the rate at which they are cleared, and at least a fifth have already been disturbed in this way. In a recent pan-tropical assessment, Burivalova et al. demonstrate the importance of logging intensity as a driver of biodiversity decline in timber estates. Their analyses reveal that species richness of some taxa could decline by 50% at harvest intensities of 38 m3 ha-1. However, they did not consider the extraction techniques that lead to these intensities. Here, we conduct a complementary meta-analysis of assemblage responses to differing logging practices: conventional logging and reduced-impact logging. We show that biodiversity impacts are markedly less severe in forests that utilise reduced-impact logging, compared to those using conventional methods. While supporting the initial findings of Burivalova et al., we go on to demonstrate that best practice forestry techniques curtail the effects of timber extraction regardless of intensity. Therefore, harvest intensities are not always indicative of actual disturbance levels resulting from logging. Accordingly, forest managers and conservationists should advocate practices that offer reduced collateral damage through best practice extraction methods, such as those used in reduced-impact logging. Large-scale implementation of this approach would lead to improved conservation values in the 4 million km2 of tropical forests that are earmarked for timber extraction

Effects of logging on stand damage in the rainforest of South-eastern Nigeria

Study was carried out in the tropical high forest of Iwuru community in south-eastern Nigeria to examine the extent of stand damage to unlogged trees at different logging intensities. Twenty four plots of 1 ha each were laid and were classified as lightly logged, moderately logged, severely logged and unlogged (control). Each category had six plots. Data on level of tree damage was taken and calibrated into various classes as “good”, “minimal”, “moderate”, and “severe” damage. Means, analysis of variance and the post hoc test were the statistical models employed to analyzedata. A positive correlation was observed between logging intensities and damage level to stands of non-logged trees with the number of trees destroyed increasing with logging intensity. Data on stocking indicated that the unlogged plot had a statistical mean of 41.5833 and a sum of 38.8%, which was the highest. The lowest statistical mean of 12.2083and the sum of 11.4% were for severely logged plots, indicating that the population of unlogged trees diminished with increasing logging intensity. Also, the large F value (11.971) and the low P value (0.000) indicated that logging intensity had significant contribution to the extent of damage to unlogged trees in the various sample plots. The post hoc test gave a value of 0.839, which is positively significant, indicating a significant, contribution of logging intensities to the damage done to unlogged trees

Reconciling timber extraction with biodiversity conservation in tropical forests using reduced-impact logging

Over 20% of the world's tropical forests have been selectively logged, and large expanses are allocated for future timber extraction. Reduced-impact logging (RIL) is being promoted as best practice forestry that increases sustainability and lowers CO2 emissions from logging, by reducing collateral damage associated with timber extraction. RIL is also expected to minimize the impacts of selective logging on biodiversity, although this is yet to be thoroughly tested. We undertake the most comprehensive study to date to investigate the biodiversity impacts of RIL across multiple taxonomic groups. We quantified birds, bats and large mammal assemblage structures, using a before-after control-impact (BACI) design across 20 sample sites over a 5-year period. Faunal surveys utilized point counts, mist nets and line transects and yielded >250 species. We examined assemblage responses to logging, as well as partitions of feeding guild and strata (understorey vs. canopy), and then tested for relationships with logging intensity to assess the primary determinants of community composition. Community analysis revealed little effect of RIL on overall assemblages, as structure and composition were similar before and after logging, and between logging and control sites. Variation in bird assemblages was explained by natural rates of change over time, and not logging intensity. However, when partitioned by feeding guild and strata, the frugivorous and canopy bird ensembles changed as a result of RIL, although the latter was also associated with change over time. Bats exhibited variable changes post-logging that were not related to logging, whereas large mammals showed no change at all. Indicator species analysis and correlations with logging intensities revealed that some species exhibited idiosyncratic responses to RIL, whilst abundance change of most others was associated with time. Synthesis and applications. Our study demonstrates the relatively benign effect of reduced-impact logging (RIL) on birds, bats and large mammals in a neotropical forest context, and therefore, we propose that forest managers should improve timber extraction techniques more widely. If RIL is extensively adopted, forestry concessions could represent sizeable and important additions to the global conservation estate – over 4 million km2

Stand structure and development after selective logging with systematically aligned skid trails, directional felling and climber cutting in a dipterocarp rainforest in Sabah, Malaysia

The tropical rainforests around the world are extremely diverse and support a huge number of timber tree species and have therefore been severely logged. One area that has produced, and still produces, large amounts of timber is Southeast Asia. In this region the most commercially important timber trees belong to the family dipterocarpacae, (dipterocarps). Logging is mostly carried out relatively unplanned and causes therefore great damage to the residual stand. Better planned logging and silvicultural activities, using (for instance) planned skid trails, directional felling and climber-cutting, should reduce the damage and create healthier residual stands. This study tested a logging method involving systematically aligned skid trails combined with directional felling, called supervised logging (SL) and compared it to the conventional logging (CL) practiced in the area. Both logging methods were combined with (CC) and without (NCC) climber cutting. All trees exceeding 10 cm in diameter at breast height (dbh), and a random selection of seedlings and saplings were measured before logging (1992) and for a period of eight years after logging (1993-2001). More trees tended (0.050 < P ≤ 0.100) to be logged where CL was applied than in SL plots (the mean numbers of all stems and dipterocarps logged per ha were 13.0 and 12.4, respectively, in CL plots, compared to 9.4 and 6.7 in SL plots). The skid trail network applied in SL resulted in disturbance to around 7 % of the soil cover. The corresponding figure for the unplanned skid trail network in CL was higher (ca. 10 %), but not significantly different. Climber cutting resulted in four more dipterocarp trees being logged ha-1, compared with NCC: a statistically significant difference (P ≤ 0.050). Basal area lost or severely damaged differed between methods for some diameter classes with mainly CL leading to greater losses. The residual stand contained statistically significantly more dipterocarp seedlings after CL than after SL, while saplings and trees showed the opposite trend, i.e. more individuals were left in the residual stand after SL than after CL. There were significantly (ca. 30%) more 10-29 cm dbh dipterocarp trees in the residual stand after SL than after CL. Cutting climbers had no initial effect on the residual stand in terms of densities of seedlings, saplings trees of either all species or dipterocarps. Data collected during the subsequent period show inter alia, that the net basal area increased at similar rates following both logging methods, considering all species. There was also no significant difference between SL and CL in terms of dipterocarp net basal area, although this parameter grew by 1.0 m2 ha-1 after SL and declined by 0.1 m2 ha-1 after CL. Climber cutting significantly and positively affected net basal area growth, which amounted to 6.4 m2 ha-1 and 3.3 m2 ha-1 in the CC and NCC plots, respectively. The substantially higher growth associated with CC was mainly due to the growth and recruitment of small trees, mainly pioneer species

Effect of logging wounds on diameter growth of beech (Fagus orientalis Lipsky) trees following selection cutting in Caspian forests of Iran

Background Logging damage to residual trees during selection cutting may lead to serious economic losses in terms of both timber quality and diameter growth reduction. In this study, we investigated the effect of logging operations on residual tree damage and the consequence of injuries on diameter growth in an uneven-aged mixed forest dominated by beech (Fagus orientalis Lipsky)

Forest Residue Management Impact on Rodent (Rodentia: Murinae, Arvicolinae) Damage in Pedunculate Oak (Quercus robur L.) Forests in Croatia

Small rodents (Rodentia, subfam. Murinae: real mice, Arvicoline voles) greatly affect natural regeneration, stability and dynamics of forest communities worldwide. Every 3–4 years rodent damage in Croatian state forests is the most severe in forest regeneration stands, especially in pedunculate oak (Quercus robur L.) and narrow-leaved ash (Fraxinus angustifolia Vahl.) forests, where rodents can seriously impede natural regeneration by damaging seeds, stems and roots of saplings. These negative interactions are an even bigger challenge nowdays as pedunculate oak and narrow-leaved ash have become more vunerable in the last decades and are known as the most sensitive species of lowland forests in Croatia due to microclimatic and macroclimatic changes and the unfavourable interaction of a whole series of anthropogenic, abiotic and biotic factors. In the last 40 years, in Croatian state forests, rodent management consisted of monitoring and mainly rodenticide use. Trying to implement IPM (Integrated Pest Management) postulates into practice over the years, different prevention methods against small rodents were tested, but not many came to use. The aim of this research was to look into different logging residue management approaches and their effect on the rodent damage in two pedunculate oak forest regeneration stands in central Posavina in Croatia. Rodent damage on stem and root of tree saplings was recorded by visual inspection on three plots (5x5 m) with scattered logging residue, and one plot (5x5 m) with no residue at one micro-depression site (95 m a.s.l.), and on one micro-elevation (99 m a.s.l.) site. Plots with scattered logging residue represented a type of forest residue management in which logging debris (branches) is cut to smaller lengths and distributed evenly at the forest regeneration stand. Plot with no logging debris represented a residue management method in which wood mass is completely removed from the regeneration stand after felling. We counted, determined and inspected tree saplings found at chosen plots for rodent damage (on stem and roots) and also determined the average weight and moisture content of logging residue (branches around 5–7 cm in diameter) found at the site. In spring 2017, 3380 tree saplings (2978; 81% pedunculate oak, 7; 0.2% narrowleaved ash and 395; 11.7% other deciduous species) were inspected for rodent damage. At micro-depression site, on a plot with no logging residue, only 13.4% of the saplings were damaged, while the average share of damaged saplings on three plots with scattered residue was more than six times higher; 87.8%. The average mass of the logging residue weighed at site with scattered residue was 10.14 kg kg/m2 and moisture content was 19.2%. At microelevation site, 25.4% of the saplings were damaged on a plot with no logging residue, while the average share of damaged saplings on three plots with scattered residue was two times higher; 51.4%. The average mass of the logging residue weighed at SRP 1–3 was 5.1 kg/m2. We also determined moderately strong positive correlation (R=0.69133) between the mass of logging residue and rodent damage and strong negative correlation (R=–0.89598) between wood moisture content of the logging residue and rodent damage. In years ahead, with unpredictable climate effects and potentially very variable small rodent dynamics, removing the logging residue after the felling could represent a residue management that contributes to a more effective and ecologically based rodent management. It could also become a usable preventive method within IPM and help prevent sever rodent damage, even during the outbreaks in pedunculate oak regeneration stands

Sustainable Harvesting of Tropical Rainforests: Reply to Keto, Scott and Olsen

This paper refutes the Keto et al. proposition that the Queensland selection logging system is neither ecologically nor economically sustainable. The key requirements of this system are: (1) that logging guidelines are sympathetic to the silvicultural characteristics of the forest, ensuring adequate regeneration of commercial species and discouraging invasion by weeds; (2) tree-marking by trained staff specifies trees to be retained, trees to be removed and the direction of felling to ensure minimal damage to the residual stand; (3) logging equipment is appropriate and driven by trained operators to ensure minimal damage and soil disturbance, compaction and erosion; (4) prescriptions ensure that adequate stream buffers and steep slopes are excluded from logging; (5) sufficient areas for scientific reference, feature protection and recreation are identified and excluded from logging; and (6) that deficiencies in an evolving system are recognized and remedied, leading to an improved system. Many studies of the effects of logging in these forests have been published and collectively provide a unique demonstration of one possible approach to sustainable timber harvesting