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Xie X.-K.,CAS Shenyang Institute of Applied Ecology | Xie X.-K.,Hunan Agricultural University | Liu Z.-G.,CAS Shenyang Institute of Applied Ecology | Liu Z.-G.,LIAONING Technical University | And 5 more authors.
Chinese Journal of Ecology | Year: 2011

Taking the original broad-leaved Korean pine forest in Changbai Mountain of Northeast China as test object, and by using density-dependent matrix model, this paper simulated the temporal dynamics of diameter distribution of the stand under natural growth scenario, analyzed the effects of a selection harvest scenario on the diameter distribution, and calculated the recover periods of seven harvest scenarios. The forest was relatively stable, but still had a slow natural growth. The stand density declined, which accorded with the self-thinning law of forest. The change rate of the tree number of each diameter class weakened gradually over time, and the stand density became relatively fixed, which validated the theory of succession climax. Based on the indices for assessing the effect of forest management, including harvest level, structure of preserved stands, and harvest cost, it was considered that, 20% harvest intensity with an interval of 35 years and 25% harvest intensity with an interval of 45 years would be the two of the most optimal harvest scenarios. Source


Wu Z.,CAS Shenyang Institute of Applied Ecology | Wu Z.,LIAONING Technical University | Wu Z.,University of Chinese Academy of Sciences | Su D.,Jilin Forest Industry Group Ltd Liability Company | And 8 more authors.
Chinese Geographical Science | Year: 2016

In order to identify a harvesting model which is beneficial for broadleaf-Korean pine mixed forest (BKF) sustainability, we investigated four types of harvested stands which have been logged with intensities of 0 (T0, control), 15% (T1, low intensity), 35% (T2, moderate intensity), and 100% (T3, clear-cutting), and examined the impacts of logging intensity on composition and structure of these stands. Results showed that there were no significant differences between T0 and T1 for all structural characteristics, except for density of seeding and large trees. The mean diameter at breast height (DBH, 1.3 m above the ground), stem density and basal area of large trees in T2 were significantly lower than in T0, while the density of seedlings and saplings were significantly higher in T2 than in T0. Structural characteristics in T3 were entirely different from T0. Dominant tree species in primary BKF comprised 93%, 85%, 45% and 10% of the total basal area in T0, T1, T2 and T3, respectively. Three community similarity indices, the Jaccard′s similarity coefficient (CJ); the Morisita-Horn index (CMH); and the Bray-Curtis index (CN), were the highest for T0 and T1, followed by T0 and T2, and T0 and T3, in generally. These results suggest that effects of harvesting on forest composition and structure are related to logging intensities. Low intensity harvesting is conductive to preserving forest structure and composition, allowing it to recover in a short time period. The regime characterized by low logging intensity and short rotations appears to be a sustainable harvesting method for BKF on the Changbai Mountains. © 2016, Science Press, Northeast Institute of Geography and Agricultural Ecology, CAS and Springer-Verlag Berlin Heidelberg. Source


Dai L.,CAS Shenyang Institute of Applied Ecology | Wang Y.,CAS Shenyang Institute of Applied Ecology | Wang Y.,University of Chinese Academy of Sciences | Su D.,CAS Shenyang Institute of Applied Ecology | And 6 more authors.
Environmental Management | Year: 2011

In this article, we introduce China's major forest types and discuss the historical development of forest management in China, including actions taken over the last decade toward achieving SMF. Major challenges are identified, and a strategy for SFM implementation in China is presented. China's forests consist of a wide variety of types with distinctive distributional patterns shaped by complex topography and multiple climate regimes. How to manage this wide array of forest resources has challenged forest managers and policy-makers since the founding of the country. Excessive exploitation of China's forest resources from the 1950s to the late 1990s contributed to environmental problems and calamities, such as floods, soil erosion, and desertification. At the start of the new millennium, the Chinese government decided to shift its emphasis from timber production towards the achievement of sustainable forest management (SFM). With a series of endeavors such as the implementation of the "Six Key Forestry Projects" and the reform of forest tenure policies, and the adoption of a classification system for China's forests, a beginning has been made at reversing the trend of environmental degradation that occurred throughout the latter half of the last century. At the same time, huge challenges remain to be tackled for the development of forestry in China. © 2011 Springer Science+Business Media, LLC. Source


Xie X.-K.,CAS Shenyang Institute of Applied Ecology | Xie X.-K.,Hunan Agricultural University | Su D.-K.,CAS Shenyang Institute of Applied Ecology | Su D.-K.,Jilin Forest Industry Group Ltd Liability Company | And 4 more authors.
Chinese Journal of Ecology | Year: 2011

The traditional forest management modes in China are rather lagged behind. Their digitalization level is relatively low, and their decision-making processes are somewhat subjective, without using explicit data and information. To integrate forest dynamics models into geographic information system to develop forest management decision support system could fully bring the visualization and spatial analysis technologies as well as the model simulation and prediction functions into play, and strengthen the capability of dealing with forest dynamic changes at large spatiotemporal scales. This paper designed and actualized forest growth model, landscape harvesting model, and matrix model, and developed a sustainable forest management decision support system to answer the questions "what, where, and how" in forest harvesting practices. The decision support system was applied in Lushuihe and Sanchazi forestry bureaus of Changbai Mountain area, which could provide broader implication for the digital technique applications in forest management in China. Source


Wu Z.J.,CAS Shenyang Institute of Applied Ecology | Wu Z.J.,LIAONING Technical University | Su D.K.,Jilin Forest Industry Group Ltd Liability Company | Niu L.J.,Changbai Mountain Academy of science | And 5 more authors.
Shengtai Xuebao/ Acta Ecologica Sinica | Year: 2015

China's Natural Forest Conservation Program was launched in 1998. Since then, a harvesting model based on logging broadleaved species while retaining Pinus koraiensis has been widely applied in the Changbai Mountain region of Northeast China. The primary goal of this model is to promote the return of degraded secondary forests to primary broadleaved Korean pine mixed forests (BKFs). However, because of differences in tree species composition among secondary forests, this harvest model has led to a decrease in timber resources in some parts of the region. In order to explore a sustainable utilization program for BKFs, we simulated the dynamics of total timber stocks under different harvest scenarios. We selected five secondary 1-hm2 BKF plots, which had been established in 2007 in the area administered by the Lushuihe Forestry Bureau. In these plots, Pinus koraiensis accounted for approximately 20%, 30%, 40%, 50%, or 60% of the gross volume. We divided each plot into 25 subplots, each measuring 20 m×20 m. Within these plots, we identified and measured all free-standing trees with a diameter at breast height of ≥2 cm at 1.3 m above the ground. To simulate volume dynamics in the plots, we divided the tree species into three groups, namely, conifer trees, commercial broadleaved trees, and other trees. For each group, we applied volume growth equations and survival index equations to predict the volume dynamics of stands. In addition, we tested the validity of the harvesting model by using paired t-tests to analyze data obtained over a 10-year period from 10 permanent plots, ranging in area from 0.25 hm2 to 0.5 hm2. We calculated the gross volumes and the volumes available for harvesting of stands under a range of management programs, with harvest intensities of 20%, 30%, or 40% and cutting cycles of 10 years, 20 years, 30 years, or 40 years. In addition, we divided the programs into two groups: in the first group, harvesting of Pinus koraiensis was permitted, whereas in the second group, harvesting of Pinus koraiensis was prohibited. We verified the validity of the harvesting model (t=0.229, P=0.829). The logging schemes that prohibited harvesting of Pinus koraiensis not only restricted the volume of available timber but also made restoration more difficult. Even under the lowest harvest intensity of 20%, the available timber volumes did not return to original levels after 40 years of restoration in secondary forests, where Pinus koraiensis comprised >40% of the total volume. Hence, to achieve sustainable utilization in secondary forests, the characteristics of tree composition should be considered when developing harvest schemes. For secondary forests in which Pinus koraiensis comprises >40% of the total volume, the harvest scheme should permit harvesting of Pinus koraiensis with a cutting intensity of 20% at 30-year intervals. In contrast, for secondary forests in which Pinus koraiensis comprises < 40% of the total volume, the harvest scheme should prohibit harvesting of this species, with a cutting intensity of 20% at 40-year intervals. We further showed that the period required for restoring the volume available for harvesting was longer than the period required for restoring the gross volume. Hence, evaluation of the logging cycle according to the period required for restoring the volume available for harvest will more efficiently promote sustainable forest utilization. © 2015, Ecological Society of China. All Rights Reserved. Source

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