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25 May 2019, Volume 55 Issue 5
Contents
 
2019, 55(5):  0-0. 
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Articles
Effects of Girdling on Stem CO2 Efflux and Its Temperature Sensitivity of Populus tomentosa
Zhang Xixi, Yang Qingpeng, Liu Liang, Wang Qingtao, Li Fei, Guo Lili, Hao Lihua, Cao Xu, Fan Xiaodong, Liang Weijia, Zheng Yunpu
2019, 55(5):  1-10.  doi:10.11707/j.1001-7488.20190501
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[Objective] This study aimed to investigate the mechanism of photosynthate supply on stem CO2 efflux and its temperature sensitivity of tree trunk surface, which is not only critical for understanding the carbon cycling processes of forest ecosystem, but also provides theoretical basis for forest and plantation management under global climate change.[Method] In this study, 10-year-old Populus tomentosa plantation was taken as the research object, and a random block experiment was conducted with three plots (30 m×30 m)in Chinese white poplar (P. tomentosa) plantation in northern China. A girdling experiment on the tree stems was operated to change the supply of photosynthate. The stem CO2 efflux (Es) and stem temperature (Tstem) of Chinese white poplar were measured to examine the effects of photosynthates supply on the temperature sensitivity (Q10) of Es above girdle (AG) and below girdle (BG). Meanwhile, the dynamic changes of nonstructural carbohydrates in stem tissue were measured for comparing different responses of Es and Q10 to substrate supply in growing and non-growing seasons.[Result] 1) Es of AG was increased by 57% and Es of BG was decreased by 43% in growing season after the 30-day girdling treatment, whereas no obvious difference in Es was detected among NG, AG, and BG in non-growing season. 2) Soluble sugar contents of the AG and BG in growing season were decreased by 29% and 15%, respectively. Similarly, the soluble sugar content of AG was also decreased by 15%, but the soluble sugar content of BG was increased by 10% in non-growing season. 3) We also found exponential relationships between Es and stem temperature in both growing and non-growing seasons, but the R squares (R2) of the exponential relationship between Tstem and Es at AG and BG were decreased under stem girdling treatment. 4) Both the Q10 and stem basal respiration rate (R15) at AG were increased, while those of BG were decreased under stem girdling treatment.[Conclusion] Stem girdling blocked the import of photosynthates, and thus altered the soluble sugar contents of AG and BG. Stem girdling resulted in increases in the Es and Q10 at AG, but led to decreases in the Es and Q10 at BG. The responses of stem CO2 efflux and its temperature sensitivity to stem girdling were obviously different between growing season and non-growing season.
Spatial Variation of the Density of Soil Organic Carbon in Forest Land on the Southern Slope of Qinling Mountains
Wei Wei, Dang Kunliang
2019, 55(5):  11-19.  doi:10.11707/j.1001-7488.20190502
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[Objective] The patterns of spatial variation of the density of soil organic carbon (SOC) in forest land was studied on the southern slope of Qinling Mountains in Shaanxi Province, which provided a theoretical basis for the scientific management of SOC in Qinling Mountains.[Method]Sample plots were set up in different forest regions (Changqing of Yang County, Longcaoping of Foping County, Taibai Mountain of Taibai County, Ningdong of Ningshan County and Ningxi of Ningshan County) and different site conditions (elevation, slope aspect, slope position and slope) on the southern slope of the Qinling Mountains. Investigation, sampling and determination were carried out. Difference tests were used to analyze the effects of different site factors on SOC density (tC·hm-2). Stepwise regression analysis was employed to quantify the relative importance of each factor on the variation of SOC density.[Result]The average SOC density was 125.41 tC·hm-2(52.60-307.36 tC·hm-2)on the southern slope of Qinling Mountains, which were 59.04, 41.65, and 24.73 tC·hm-2 in 0-10, 10-30, and 30-60 cm soil layers respectively, accounting for 47.07%, 33.21% and 19.72% of the total SOC density, respectively. The SOC density varied greatly among different regions on the southern slope of Qinling Mountains, showing Longcaoping of Foping County (143.55 tC·hm-2), Ningdong of Ningshan County (138.37 tC·hm-2), Ningxi of Ningshan County (134.09 tC·hm-2), Taibai Mountain of Taibai County (109.25 tC·hm-2), and Changqing of Yang County (90.22 tC·hm-2). The SOC density firstly increased and then decreased with increasing altitude. The SOC density (90.24 tC·hm-2) was the lowest at 800-1 200 m above sea level, and the SOC density (166.43 tC·hm-2) was the highest at the 2 000-2 400 m above sea level. When the altitude was higher than 2 400 m, the SOC density decreased, with an average of 132.51 tC·hm-2. The SOC density (127.23 tC·hm-2) of shady slope was slightly higher than that (123.25 tC·hm-2) of sunny slope. The SOC density decreased from 147.52 to 87.06 tC·hm-2 with the increase of slope. The SOC density in the down slope (166.36 tC·hm-2) was higher than those in the middle (129.43 tC·hm-2) and up-slope (77.14 tC·hm-2).[Conclusion] The variations of SOC density among different forest regions were significant. The trend was increased first and then decreased with the increase of elevation. Significant differences (P<0.05) or extremely significant differences (P<0.01)of SOC density appeared in elevation ranges and different slope position. However, the difference of SOC density was not significant between shady slope and sunny slope. Stepwise regression analysis showed that the slope position and elevation were the dominant topographic factors that affect the SOC density. Compared with other forest areas in China, the SOC density in forest land on the southern slope of Qinling Mountains was at a higher level in the country. The SOC on the southern slope of Qinling Mountains plays an important role in the soil carbon pool of forest ecosystem in China and the management should be strengthened.
Selection of La and Ce Hyper-Tolerant Plants for Vegetation Rehabilitation in Light Rare Earth Tailing
Wei Guangpu, Yan Wei, Yu Xiaoyan, Wei Jie, Xiao Fengjie
2019, 55(5):  20-26.  doi:10.11707/j.1001-7488.20190503
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[Objective]The paper was intended to measure the contents of light rare earth elements in the soil and the contents of La and Ce and their distributions in plant in a light rare earth tailings in north China, Biological Transfer Coefficient (BTC) and Biological Absorption Coefficient (BAC) of the plants for La and Ce absorptions were calculated for the selection of La and Ce hyper-tolerant plants, in order to provide a scientific basis for landscape restoration in the tailings.[Method]Study site was selected at the edge of the rare earth tailings and 12 sampling plots were set up in 4 directions of south-east, north-west, north-east, and south-west according to the wind direction at 50, 100 and 300 m from the mine pit. Firstly, the 0 to 20 cm surface soil samples were collected using the 5-points collection and quarter-division method, and plant samples were collected from the above-ground organs and the roots of the trees planted by the rehabilitation program (Haloxylon ammodendron, Caragana microphylla, Hedysarum scoparium, Lespedeza bicolor, Nitraria tangutorum, and Populus tomentosa). Secondly, the contents of light rare earth elements La, Ce, Pr, Nd, Sm, Pm, and Eu in the soil and the contents of La and Ce in the plants were measured by ICP. Furthermore, the average of the single factor pollution index of soil in the surrounding areas of the tailings was analyzed with the N. L. Nemerow comprehensive index method. Lastly, the plant transfer efficiency was evaluated by the BTC and the plant absorbing ability of La and Ce was evaluated by BAC.[Result]The average contents of La, Ce, Pr, Nd, Sm, Pm, and Eu in the soil of the light rare earth tailings were 2 762.46, 5 440.42, 1 308.42, 1 604.11, 133.96, 28.12 and 40.53 mg·kg-1 respectively, and the contents of La and Ce accounted for 72% of total contents. The order of these contents in the surface soil of all directions was south-east > north-east > south-west > north-west, all the values of which were 25.10 to 230.56 times higher than the geometric mean value (background value) of Inner Mongolia. Also, the single factor pollution indices of all directions were greater than 3, which could ascertain that the surrounding areas of the light rare earth tailings were seriously polluted. Then, the average values of the single factor pollution index in the south-east direction were 69.06 to 544.10, which were the highest. By contrary, the values in northwest were 5.99 to 19.75, which were the lowest. Meanwhile, the values in the north-east and south-west directions were similar. On the one hand, the La and Ce contents of the above-ground organs of H. ammodendron, L. bicolor and N. tangutorum were all higher than those in the roots. On the other hand, the La and Ce contents of the roots of C. microphylla, H. scoparium and P. tomentosa were all higher than those in the above-ground organs. At last, the BTC of La and Ce of H. ammodendron, L. bicolor and N. tangutorum ranged from 1.03 to 1.76. The BAC of La and Ce of L. bicolor ranged from 1.00 to 1.72. Only the BTC and BAC of L. bicolor were both greater than 1.[Conclusion]L. bicolor was the hypertolerant plant of La and Ce, which might be significant for the remediation of light rare earth polluted soil. The other 5 plant species can be used as tolerant to light rare earth elements.
Long Term Water-Nitrogen Coupling Effect on Stand Volume of Different Clones of Populus tomentosa
Zhu Jialei, Bo Huijuan, Li Xuan, Wen Chunyan, Wang Jiang, Nie Lishui, Tian Ju, Song Lianjun
2019, 55(5):  27-35.  doi:10.11707/j.1001-7488.20190504
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[Objective] In Wei County nursery of Hebei province, we applied different irrigation and nitrogen addition treatments to study the long-term water-nitrogen coupling effect on stand volume of Populus tomentosa.[Method] A split plot experiment design was used to study effects of different water-nitrogen coupling treatments in forest land on stand volume of different clones of P. tomentosa.[Result] Results showed that:1) different irrigation and nitrogen application had significantly different effects on stand volume of different clones. Clone S86 had better response mechanism under high water and fertilizer treatment, but it was opposite to clone 1316. 2) during irrigation to poplar plantation, the field capacity of more than 75% should be set as the critical value of irrigation, and the afforestation region of the environmental conditions, such as planting density, forests age and other factors, should be taken into account. 3) It is suggested that the range of nitrogen fertilizer to poplar plantation should be between 100 kg·hm-2 to 400 kg·hm-2, and the amount of fertilization should be adjusted to the fertility level in the experiment area.[Conclusion] Through the comparative study, clone S86 is suitable for the experimental design in the area with field capacity of 75% and nitrogen application rate of 160 g per tree as a fast-growing among the 4 clones (BT17, B331, S86,1316). We suggest that the cultivation of fast-growing and high-yielding poplar plantations in the near areas should be given priority. The results provide scientific theoretical basis for directional cultivation of Populus tomentosa plantation, and put forward a scientific and reasonable variety (line) selection criteria with high-quality, fast-growing and high-yield.
Differences in Metabolic Functions of Soil Microbial Communities of Chinese Fir Plantations of Different Ages
Wang Chaoqun, Jiao Ruzhen, Dong Yuhong, Hou Lingyu, Zhao Jingjing, Zhao Shirong
2019, 55(5):  36-45.  doi:10.11707/j.1001-7488.20190505
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[Objective] This paper aimed to study the differences in soil physical and chemical properties and utilization of carbon source by microbial communities, and the influences of stand age of Chinese fir plantationson soil microbial functional diversities, so as to provide a theoretical basis for sustainable management of Chinese fir plantation.[Method] The 3-, 12-and 38-year-old Chinese fir plantations were targeted in Wuyi Mountain, Fujian Province. Biolog-ECO method was used to study the characteristics of carbon utilization by soil microorganisms in the topsoil layer (0-20 cm) of Chinese fir plantations at different stand ages. The heatmap analysis, principal component analysis (PCA) and correlation analysis were used to reveal the differences in use of various carbon sources by microorganisms and the main influencing factors that cause differences.[Result] The results showed that the metabolic activity, Shannon-Wiener diversity index (H'), Pielou evenness index (J),Simpson diversity index (D), McIntosh Diversity Index (U) and McIntoshevenness index(E) all gradually increased with the increase of stand age. The metabolic activity of soil microbial community in 38-year-old Chinese fir plantation was significantly higher than that of 12-and 3-year-old Chinese fir plantation (P<0.05). And the utilization intensity of phenolic acids, amines and amino acids in 38-year-old Chinese fir plantation was higher, that of phenolic acids, polymers and amino acids in 12-year-old Chinese fir plantation was higher, and that of polyphenols, carboxylic acids and carbohydrates in 3-year-old Chinese fir plantation was higher. In 38-year-old Chinese fir plantation, the utilization intensity of carbohydrates, amino acids, carboxylic acids and amines was significantly higher than that in 3-year-old Chinese fir plantation, while there was no significant difference in the utilization intensity of the six types carbon sources by soil microbial communities between 12-year-old and 3-year-old (P>0.05). The results of heatmap analysis showed that soil microbial community of 38-and 12-year-old Chinese fir plantations could metabolize 31 kinds of carbon sources, while the soil microbial community of 3-year-old Chinese fir plantation could only metabolize 19 kinds of carbon sources. Among environmental factors, soil pH, total nitrogen and carbon to nitrogen ratio (C:N) had significant effects on the metabolic function of microbial communities.[Conclusion] The results showed that the soil microbial community of 38-year-old Chinese fir plantation had the highest metabolic activity and diversity, and the 3-year-old had the lowest among the three forest ages. The pH and total N content increased with the increase of forest age, and the carbon to nitrogen ratio decreased with the increase of forest age, indicating that the stand age was an important factor driving soil biotic and abiotic changes in Chinese fir plantations.
Structure of Seed Coat of Albizia julibrissin and Its Relationship with Water Uptake
Chen Li, Dai Song, Ma Qingjiang, Deng Xianjing, Zhu Mingwei, Li Shuxian
2019, 55(5):  46-54.  doi:10.11707/j.1001-7488.20190506
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[Objective] The seeds of Albizia julibrissin, collected from Suqian of Jiangsu Province, were used to identify the main water entry sites during imbibition. The structure of seed coat of A. julibrissin and the relationship with water uptake were studied to explore the mechanism of dormancy breaking of A. julibrissin seeds.[Method] Taking the healthy full seeds without pest and disease as material, the structure of seed coat of A. julibrissin was observed by a stereo microscopy and a scanning electron microscopy (SEM). The effect of seed coat structure on water absorption was studied by dye-tracking and vaseline sealing experiments.[Result] The seed coat of A. julibrissin is impervious to water. Soaking treatment with hot water at different temperatures (60℃,70℃,80℃) was able to efficiently break the hardness of the seeds, however the seed viability decreased with the increase of hot water temperature. Structural characteristics of the seed coat were also examined. A. julibrissin seeds were irregular flat ellipse and had a hard and opaque seed coat with a yellowish-brown colour. There was a protruding oval-shaped edge which was a large fissure in the seed coat parallel to the macroaxis of seed. SEM images showed that from exterior to the interior the seed coat consisted of five layers:the epidermal layer, the palisade layer, the osteosclereid layer, the stereid layer, and the parenchymal cell. There were many cracks with different size, shape and depth in the seed coat. Micropyle and lens were closed and its hilum was covered by wax, vascular bundles extended parallel to the surface of the seed coat from the hilum. Morphological changes during dormancy breaking were also evaluated. Micropyle opened, the thickness of wax layer in hilum reduced, and a large crack appeared in the lens after the hot water treatment. Blocking experiments showed that all parts of treated seeds could absorb water, but the quantity of water uptake at the end of cotyledon was always the lowest. After incubation for 4 h, the most of water was imbibed by the hilum region. Subsequently, water uptake in the middle of seeds quickly increased. It was notable that water absorption was not significantly different between treatments exposing the hilum region and the middle part of seeds, but these two treatments had significantly higher water absorption values than the treatment exposing the cotyledons extremities after 12 h steeping conditions. The difference trend remained until the water absorptivity of A. julibrissin seeds reached saturation. Aniline blue staining showed that the seed coat could absorb water in 3 ways:1) crack at lens, 2) gaps in the micropyle and hilum, and 3) the epidermis layer of the seed. Water first entered the seed coat from the lens and moved along the vascular bundles within it. Then there was water entering the seed through micropyle and hilum. After that, water also permeated through the epidermal layer which was the outermost layer of seed coat. However, palisade layer hindered the further entry of water into the seed. The first red staining appeared in the radicle after 2 h of soaking in TTC solution, then water moved to the end of cotyledon. In horizontal direction, water penetrated from the edge of the cotyledons to the middle.[Conclusion] Treated in water at 70℃ for 5 minutes was the optimum method to break dormancy of A. julibrissin seeds. The series experiments indicated that nondormant seeds could absorb water throughout the entire seed coat, but the initial site of water absorption was the lens followed by the micropylar and hilum. After water entered the embryo it moved from the radicle to the terminal cotyledon. The hardness of seeds possibly relates to the structures of palisade layer, light line, parenchymal cell and the wax which covered the hilum and filled in vascular bundle.
Difference Analysis of Growth and Nitrogen Utilization and Distribution in Photosynthetic System of Catalpa bungei Intraspecific and Interspecific Hybrids
Xiao Yao, Yi Fei, Han Donghua, Lu Nan, Yang Guijuan, Zhao Kun, Wang Junhui, Ma Wenjun
2019, 55(5):  55-64.  doi:10.11707/j.1001-7488.20190507
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[Objective] This study aims to clarify the differences in growth and photosynthetic capacity of intraspecific and interspecific hybrids of Catalpa, and to explore the potential relationship between growth and photosynthetic capacity which is regulated by nitrogen use and distribution in leaves, and to provide favorable basis for Catalpa cultivation and genetic improvement.[Method] The experiment was designed with complete random block design, the height of 1-5 years old trees and DBH of 1-6 years old trees of the Catalpa bungei×C. bungei and C. bungei×C. fargesii f. duclouxii hybrids, and leaf nitrogen content, chlorophyll content, light response curve and CO2 response curve of the Catalpa hybrids in 6 years old were measured. The non-orthogonal hyperbolic model was used to fit the light response curve to calculate the gas exchange parameters, such as the apparent quantum yield (AQY) and the light compensation point (LCP). The FvCB biochemical model (The biochemical photosynthetic model proposed by Farquhar, von Caemmerer and Berry) was used to fit to the CO2 response curve, and the maximum carboxylation efficiency (Vc max), maximum electron transfer rate (Jmax) and other photosynthetic biochemical parameters were estimated via the model. Nitrogen allocation ratio in photosynthetic system, include light-harvesting system, carboxylation system and bio-energy component, were calculated.[Result] Analysis of variance showed that tree height and DBH of intraspecific hybrids (C. bungei×C. bungei) were significantly greater than interspecific hybrids (C. bungei×C. fargesii f. duclouxii) after 2 years. There was no significant difference between the two hybrids in the total amount of chlorophyll. But the content of chlorophyll b of interspecific hybrids was significantly higher (15.08%) than intraspecific hybrids. On the other hand, the chlorophyll a/b and carotenoid/chlorophyll a+b of intraspecific hybrids was significantly higher than interspecific hybrids. The photosynthetic parameters showed that the intraspecific hybrid had a greater maximum net photosynthetic rate, stomatal conductance, maximum carboxylation efficiency and dark respiration rate. It showed that they had stronger photosynthetic capacity. There was no significant difference in leaf nitrogen content between the two hybrid types. However, more nitrogen was invested to photosystem for intraspecific hybrid leading to higher photosynthetic nitrogen utilization efficiency (PNUE). And it may be one of the reasons of high photosynthetic efficiency for intraspecific hybrid. Correlation analysis showed that the PNUE of Catalpa hybrids was significantly positively correlated with the nitrogen allocation in the carboxylation system and bioenergetics. In addition, the PNUE of intraspecific hybrid had a greater (R2=0.531) positive linear relationship with the diameter at breast height (DBH).[Conclusion] 1) Intraspecific hybrids have a stronger adaptability to the local environment (The central plains), it was the reason that growth of Catalpa bungei×C. bungei was significantly better than interspecific hybrid (C. bungei×C. fargesii f. duclouxii). 2) Compared with Yunnan-Guizhou plateau, the longer sunshine duration and higher mean temperature in July in the central plains may be the reason for the formation of a response mechanism (high level Chl a/b and Car/Chl a+b) for intraspecific hybrid to adapt to the high photosynthetic radiation environment. 3) Higher N distribution ratio and N use efficiency in photosynthetic system of C. bungei×C. bungei improved its photosynthetic ability. 4) The genetic material transmitted to the offspring by C. fargesii f. duclouxii did not have the regulatory mechanism to adapt to the environment in the central plains, this is the main reason why the growth and photosynthetic physiology of interspecific hybrids are inferior to that of intraspecific hybrids in the central plains.
Developing a System Climate Sensitive Biomass Compatible Equations for Masson Pine
Li Yacang, Feng Zhongke
2019, 55(5):  65-73.  doi:10.11707/j.1001-7488.20190508
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[Objective] Masson pine (Pinus massoniana) is an important species which is widely distributed in the subtropical zone in China. According to the national climate change assessment report, the temperature in China has raised by 0.5-0.8℃. The mean ground temperature in China might be raised by 3.9-6.0℃ to the end 2100. The method for detecting the response of biomass of Masson pine to climate change are the foundation for estimating forest biomass accurately. However, the effects of climate change on each component (wood, bark, branch and foliage) biomass in traditional systems of biomass equations without being considered. Therefore, in this study, the prediction accuracy of biomass was improved by developing a system of climate-sensitive biomass compatible equations.[Method] In this study, the method on developing systems of climate-sensitive biomass compatible equations using nonlinear simultaneous equations were proposed in detail based on the biomass data from 150 individual trees of Masson pine. The two-predictor equations with independent variables including diameter at breast height and total tree height were selected as base models for each components to develop the system of climate-sensitive biomass compatible equations. The one-fold cross validation was applied for model evaluation.[Result] Compared with the traditional biomass models without including climate factors, the prediction accuracy of the system of climate sensitive biomass compatible equations was substantially increased. In addition, the differences of biomass among different subtropical zones were also explained by the proposed system of climate sensitive biomass compatible equations, which ensured the sum of wood, bark, branch and foliage biomass equal to the total biomass.[Conclusion] The system of climate sensitive biomass compatible equations proposed in this study could be used as an effective tool to analyze the effects of climate change on each component biomass.
Forest Cover Change Detection Method Using Multi-Polarization Space-Borne SAR
Gu Xinzhi, Chen Erxue, Li Zengyuan, Zhao Lei, Fan Yaxiong, Wang Yahui
2019, 55(5):  74-84.  doi:10.11707/j.1001-7488.20190509
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[Objective] Using multipolar spaceborne SAR data, the probability density distribution characteristics of backscatter intensity ratio images were analyzed, the backscatter intensity information and image spatial context information was fused to develop a forest cover change detection method with high detection accuracy, low false alarm rate and low missing alarm rate, in order to provide technical support for the operational application of multi-polarization SAR satellite data.[Method] This study developed a forest cover change detection method that combines the "change detection method based on bi-temporal forest cover classification" (CBFC) and the "Bayesian maximum expected-Markov random field (EM-MRF) change detection method ". Firstly, based on the threshold segmentation method, the initial forest cover change map was obtained through forest/non-forest classification of bi-temporal multi-polarization SAR images. Then, Fisher feature transformation and EM-MRF classification were performed on the multi-polarization ratio image with the initial forest cover change map as training data. The results of forest cover change detection were obtained by EM-MRF iteration classification of the composite difference image converted from bi-temporal polarization (HH,HV) ratio image with Fisher feature transformation. In Xunke County, Heilongjiang Province, the effectiveness of the proposed method was evaluated based on bi-temporal ALOS PALSAR dual-polarization SAR data and the reference forest cover change map, which was obtained by visually interpretation of bi-temporal Landsat-5 images and high spatial resolution remote sensing images. And the comparative analysis was conducted between the proposed method, CBFC method and the method of combining the CBFC with EM-MRF by direct masking (CBFC-EM-MRF).[Result] The difference image obtained by Fisher feature transformation can effectively increase the contrast of the changed/non-changed category of forest cover. There are many wrongly detected small changed areas in the results of CBFC, and the false alarm rate and missed alarm rate of which are also very high. In contrast, the proposed method can improve the spatial coherence of the detection results by considering the context information of the difference image through MRF, and the false alarm rate, missed alarm rate and the accuracy were 1.58%, 11.87% and 98.36% respectively, so both the performance and the accuracy of the proposed method are better than that of CBFC and CBFC-EM-MRF.[Conclusion] The forest cover change detection method proposed in this paper has the advantages of good convergence, high reliability and demanding less user interaction, so it is of valuable reference value for the operational application of forest resource monitoring using GF-3 and the other multi-polarization SAR satellites to be launched in the future.
Identification of the Pathogens Causing Anthracnose of Camellia oleifera in Nursery and Their Resistence to Fungicides
Li He, Li Sizheng, Wang Yuechen, Liu Jun, Xu Jianping, Zhou Guoying
2019, 55(5):  85-94.  doi:10.11707/j.1001-7488.20190510
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[Objective]The objectives of this study were to identify the pathogens causing anthracnose of Camellia oleifera(oil-tea) in nursery in China and to reveal the resistance of anthracnose pathogens to fungicides, in order to provide targeted strategy for controlling oil-tea tree anthracnose.[Method]The anthracnose pathogen was isolated from C. oleifera in nursery, and its ApMat gene was amplified and sequenced by PCR. The anthracnose pathogen species were identified by phylogenetic analysis. The resistance of all strains to fungicides carbendazim, ethomyl, tebuconazole and prochlorazolam was further determined by differentiated dose method.[Result]Based on phylogenetic analysis of the ApMat locus with the neighbor-joining (NJ) method, the 95 isolates of anthracnose pathogens, collected from oil-tea trees in nurseries in Hunan, Jiangxi, Hainan, and Guangdong provinces (the important oil-tea trees production regions in China), were found belonging to four species of Colletotrichum genus:C. fructicola,C. siamense,C. camelliae and C. gloeosporioides. Among them, C. fructicola was the most abundant, accounted for 87.4%. Among these 95 strains, 31 were respectively resistant to either carbendazim or tebuconazole, with 6 of the 56 showing resistance to both carbendazim and tebuconazole. In contrast, all 95 strains were very sensitive to prochloraz. Two strains were resistant to three fungicides, carbendazim, carbendazim and tebuconazole. Comparison of the β-tubulin amino acid sequences between carbendazim-resistant and susceptible strains of Colletotrichum spp. revealed that 29 resistant strains had a mutation leading to an amino acid substitution at the position 198, from glutamicacid in the susceptible strain to alanine in the resistant strains.Furthermore, the 200th amino acid was also mutated from phenylalanine (Phe) to tyrosine (Tyr) of β-tubulin in the two strains showing resistance to both carbendazim and carbendazim.[Conclusion]The results suggest that the Colletotrichum spp. collected from oil-tea tree nurseries in China have developed serious resistance to carbendazim, diethofencarb and tebuconazole but not to prochloraz.
Ultrastructure of Antennal Sensilla of Anacampsis populella (Lepidoptera: Gelechiidae)
Xu Wei, Bi Jiarui, Liu Mei, Zhang Jihui, Zhang Yikai, Zang Liansheng
2019, 55(5):  95-103.  doi:10.11707/j.1001-7488.20190511
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[Objective] This study aimed to clarify the types, quantity, distribution and ultrastructure of antenna sensilla in adults of Anacampsis populella.[Method] The antenna sensilla in female and male adults of A. populella were observed with scanning electron microscope.[Result] Most of antennal sensilla were confined to ventral and lateral surface of the flagellum, while the minority was on scape and pedical. Based on the external morphology of the sensilla,it was able to be classified into eight types:BÖhm bristles (two subtypes, BBⅠ and BBⅡ), trichodea, basiconica (two subtypes, SBⅠ and SBⅡ), chaetica, coeloconica, auricillica, squamiformia and styloconica. Among them, trichodea, basiconica and auricillica were multiporous on cuticle, which were considered to be olfactory organ. There was no difference in morphology and distribution of the sensilla between male and female moths, but the flagellum of male antennae had 1-4 segments more than female moth. The sensilla trichodea and sensilla basiconicaⅡ of male moth were significantly longer than those of female moth. The basal diameter of sensilla chaetica and sensilla coeloconica was significantly wider than that of female moth. In addition, the amount of sensilla trichodea, basiconica, coeloconica, squamiformia and chaetica of male was significantly more than those of female.[Conclusion] The antennal sensilla of A. populella were abundant, and most of them had olfactory function. There was sexual dimorphism in number and sensilla characteristics between male and female.
Phylogenetic Analysis of Transcriptome and Three Detoxification Enzyme Families Related Genes in Anoplophora chinensis (Coleoptera: Cerambycidae)
Han Xiaohong, Lu Ciding, Hua Yin, Lin Haoyu, Shi Yufei, Wu Songqing, Zhang Feiping, Liang Guanghong
2019, 55(5):  104-113.  doi:10.11707/j.1001-7488.20190512
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[Objective]This study aimed to investigate the transcriptome information and the expression profiles of cytochrome P450 monooxygenase (P450) (CYP), carboxylesterase (CarE) and glutathione S-transferase (GST) detoxification enzymes in Anoplophora chinensis. The phylogenetic tree was constructed to explore the types and phylogenetic relationships of the three enzymatic gene families, and to provide a basis for the study of the adaptability of A. chinensis to multiple host species and the mechanism of insecticide resistance.[Method]The high-throughput sequencing technique, Illumina HiSeqTM2500, was employed for transcriptome sequencing of A. chinensis, and the data analysis. The phylogenetic analysis of detoxifying enzymes proteins with their homologous protein from close relative species of Coleoptera was conducted.[Result]The clean reads were then de novo assembled into 55 260 unigenes, and 32 247 unigenes were annotated by homologous comparison with public databases. Most unigenes were annotated in the Swiss-Prot database (99.11%), the unigenes of A. chinensis had the highest homology (60.25%) to those of Tribolium castaneum when annotated to Nr database. In the GO database, 8 083 unigenes were successfully annotated and was able to be broadly divided into 3 categories and 47 sub-types, and 4 600 unigenes matched with 162 prediction paths in KEGG database. Using gene annotation, 248 detoxification enzyme genes were found to be expressed in A. chinensis, including 139 CYP genes, 72 CarE genes, and 37 GST genes. Phylogenetic analysis showed that most of the CYP genes of A. chinensis were clustered with at least one of the related species of Coleoptera. In the P450 gene family, the number of CYP6 family was similar to other related species (Coleoptera), and contained the largest number of genes. The CarE detoxification enzyme genes were mainly composed of four types:β-esterase, neurochemotactic protein, exogenous metabolic enzyme and unknown category, and they may be involved in several processes (hormones and pheromones, nerve and developmental processes, digestion and detoxification, respectively). The GST expression mainly consisted of Microsomal GST, Sigma GST, Omega GST, Delta GST, Theta GST subfamilies, which have the function of protecting biomolecules from oxidative damage and catalytic activity.[Conclusion]This study presented the data of transcriptome, and preliminarily analyzed the expression and differentiation profiles of three detoxifying enzymes in A. chinensis, which could provide fundamental information and reference for adaptability to multi-host species, resistance of pesticides, and genetic mechanism of A. chinensis.
Relationship between Taiga Forest Communities and Environment Factors in the Kanas and Fire Disturbance Factors
Yang Yuping, Pan Cunde, Yu Gebi, Li Guihua, Liu Jing, Cui Qian, Liu Bo
2019, 55(5):  114-124.  doi:10.11707/j.1001-7488.20190513
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[Objective]This study aimed to classify forest communities, and quantitatively analyze the spatial distribution of forest communities and its relationship between environmental factors and fire disturbance factors, so as to provide the scientific guidance for conservation of species diversity and sustainable taiga forest management of Kanas in Xinjiang.[Method]The pyrogenic succession taiga forest community in Kanas was taken as the research object. Based on the survey of 149 forest community sample plots and the occurence time and severity of fire disturbance, the Two-way indicator species analysis (TWINSPAN) method was used to classify the forest communities at different successional stages in the scientific experimental area of Kanas National Nature Reserve. The redundancy analysis (RDA) method was used to rank the forest communities, the interrelationship among the distribution of forest community, environmental factors and fire disturbance factors was analyzed, and the effects of environmental factors, fire disturbance factors and its interactions on the spatial distribution of forest communities were quantitatively separated.[Result]The 149 survey plots were classified into sixteen types of forest communities by TWINSPAN. The results of the RDA ordination clearly reflected the relationship between the forest community formation and environmental factors and fire disturbance. The altitude, slope position, aspect, soil organic and total potassium content in environmental factors played an important role in the distribution of forest community. Among them, altitude, location, slope position and aspect were significantly correlated with the first RDA axis (P<0.01), soil organic and total potassium content were also significantly correlated with the first RDA axis (P<0.05). In terms of fire interfering factors, fire disturbance severity also affected the distribution of forest community. There was a highly significant correlation between fire severity and second RDA axis (P<0.01). Factor segregation showed that among the factors affecting the formation of the community, 21.96% were explained by environmental factors, 1.80% by the fire disturbance factors, 49.82% by the interaction between the above two factors, and 26.42% were not determined.[Conclusion]There are sixteen forest communities in the experimental area of Kanas National Nature Reserve. The forest community distribution is collectively controlled by environmental factors and fire disturbance factors, and the interaction between them is particularly prominent as well. Fire disturbance is an indispensable and important factor for the conservation of species diversity and the sustainable forest management of Kanas in Xinjiang.
A Measurement Method of Log Diameter for Rotary Cutting Machines Based on Image Processing
Yan Lei, Gao Xiang, Wang Tengyu, Pang Lei, Su Lin, Kang Yongzhen
2019, 55(5):  125-133.  doi:10.11707/j.1001-7488.20190514
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[Objective] A non-contact log diameter measurement method for a rotary cutting machine based on image processing technology was proposed in this paper with the aim to provide technical support for the non-contact, low-cost measurement of log diameter for a rotary cutting.[Method] In this study, a red line laser of 650 nm source and an invisible line laser source of 940 nm were added as auxiliary light sources, a Raspberry Pi camera and a USB-interface driverless high-definition industrial camera were selected for different laser light sources to acquire the images, respectively. Five methods of calculation(calculate arc length method,calculate perimeter length method,skeletal method,circle-fitting method,calculate the number of pixels in X axis, and six kinds of fitting method (Fourier fitting method, Exponential fitting method, Gaussian fitting method, Polynomial fitting method, Power fitting method, Sum of Sine method) were adopted when exploring which method is the best way to measure the diameter of the log on the premise of satisfying the precision requirements.[Result] By comparing the goodness of the different fitting method, two schemes of best fitting goodness can be obtained. They're respectively the method of calculating the number of pixels in X axis of laser line and applying the fitting method of Sum of Sine, the coefficient of determination was 0.999 8 and the standard deviation was 1.638. And the method of calculating the number of pixels in X axis of laser line and applying the fitting method of Fourier, the coefficient of determination was 0.999 8 and the standard deviation was 1.881. Furthermore, during the error analysis of log measurements to compare the two method, Fourier fitting and Sum of Sine fitting, had less difference in goodness of fitting. The average absolute error range of the Fourier fitting method was 1.7%, the standard deviation was 2.11, and the variance was 4.45. The average absolute error range of the Sum of Sine fitting method was 1.5%, the standard deviation was 4.35, and the variance was 18.95.[Conclusion] The scheme of calculating the number of pixels in X axis of laser line and applying the fitting method of Fourier can obtain the best goodness of fitting while satisfying the measurement precision of the diameter of the log for the rotary cutting machine.
Physicochemical Characterization and Enzymatic Hydrolysis of Cellulosic Component Fractionated from Microwave Liquefied Lignocellulosic Biomass
Peng Xiaopeng, Nie Shuangxi, Liu Jing, Cui Ying
2019, 55(5):  134-141.  doi:10.11707/j.1001-7488.20190515
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[Objective] The development of a solvolysis process by combining microwave heating and glycerol is a promising method to enhance the economic viability of biorefinery. The application of this technology on the pretreatment of lignocellulosic biomass is of great significance.[Method] The liquefaction treatment of Populus alba×P. glandulosa 84 K, Larix kaempferi, Phyllostachys viridis and Panicum virgatum was carried out by microwave liquefaction method. The products were divided into liquid and solid cellulose components. Using cellulose as raw material, the cellulose components were comprehensively characterized.[Result] The chemical analysis result showed that the cellulose fiber had high glucan content. Infrared spectroscopy showed that the signals of lignin and hemicelluloses gradually weakened, further confirming the effective removal of hemicelluloses and lignin in the liquefaction treatment. The result of XRD analysis showed that the cellulose fibers had high crystallinity and large surface area.[Conclusion] Compared with the original lignocellulosic biomass, the enzymolysis saccharification efficiency of the cellulose fiber of four kinds of raw materials was not improved to a certain degree, indicating the potential of cellulose fiber in liquefied solid product in the preparation of fuel ethanol.
Review
Research Methodologies for Genotype by Environment Interactions in Forest Trees and Their Applications
Lin Yuanzhen
2019, 55(5):  142-151.  doi:10.11707/j.1001-7488.20190516
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China is the largest wood importer and the second largest wood consumer in the world, and its dependence on external supply has exceeded 50% for several years. However, the average annual growth of forest per hectare in China is about half of that in the developed countries in forestry, which indicates that there is still larger gap in tree breeding in China, compared with the developed countries in forestry. Therefore, strengthening the large-scale experiments and accurate genetic evaluation of forest trees has great significance in improving the productivity of China's plantation forests through the precise selection and breeding of tree varieties. Genotype by environment interaction is one of the important contents of large-scale experiments and accurate genetic evaluation of forest trees. Genotype by environment interaction (G×E) refers to a lack of consistency in the relative performance of genotypes among different environments, and represents differences in genotype rankings or differences in performance inconstant among environments. Existing studies have confirmed that G×E is very common and often large in forest trees, and it is usually difficult to find consistently superior genotypes with broad adaptation. Since G×E can reduce heritability and genetic gain, understanding the G×E effects and their environmental drivers is vital to mating design, species/variety selection and genotype deployment. The paper reviews the current main analytical method for identifying G×E(including factor analytic method and BLUP-GGE joint analysis) and estimating heritability, and compares the strength and weakness of these analytical method (including stability analysis, type-B genetic correlation, AMMI, GGE biplot, factor analytic method and BLUP-GGE joint analysis), and also reviews the progress of G×E studies on growth traits (such as diameter at breast height, height and volume), form traits (such as stem straightness, branch angle and branch size) and wood properties (such as wood density and modulus of elasticity) in forest species (such as Pinus elliottii, Pinus taeda, Picea abies, Eucalyptus grandis, Pinus radiata and Pseudotsuga menziesii) of global economic importance. Moreover, the paper discusses the environmental drivers that cause G×E and strategies for dealing with G×E in tree breeding. Finally, the future research of G×E is proposed, alongside development of new analytical method, focusing on multi-variate model of G×E and integration of genomic selection with G×E. New genetic analysis model for forest trees should be adopted into G×E studies. The patterns and magnitude of G×E should be focused on multi-variate model for multi-environment trials. Accurate estimation of environment-specific genomic breeding values of forest trees should be performed.
Progress in Sex Pheromone Components in Geometrid Species (Lepidoptera: Geometridae) and Their Applications
Ma Tao, Huang Zhijia, Zhu Ying, Lin Na, Xiao Qiang, He Yurong, Wen Xiujun
2019, 55(5):  152-162.  doi:10.11707/j.1001-7488.20190517
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Pheromone of Lepidoptera has been studied in detail at home and abroad. This study elucidates the latest classification system of Lepidopteran sex pheromone components in which all the components are respectively categorized into TypeⅠ, TypeⅡ, TypeⅢ and Type 0. TypeⅠ, is distributed in many superfamilies of Lepidopteran, and includes alcohol, aldehydes and acetic ester compounds with carbon number ranging from 10 to 18. TypeⅡ is widely distributed in geometrid, and consists of unsaturated C17-C23 hydrocarbon and their corresponding epoxides. TypeⅢ simply consists of C17-C23 hydrocarbon with single or multiple methyl branches, and it was found only in few Lepidopteran species. Type 0 is short-chain second alcohol or ketone compounds that are analogous to plant volatile organic compounds (VOCs). At present, pheromone components of 158 geometrid species from 93 genera have been characterized. Except for Sterrhinae whose sex pheromone components are categorized mainly in Type I, the other sex pheromone components in subfamilies of geometrid are mainly categorized in TypeⅡ. Most of geometrid sex pheromone components have the long carbon chain scaffold and unsaturated hydrocarbons (TypeⅡ) in structures, which seriously affects characterization and field application. This paper clarities the double bond position, epoxy structures and chiral conformation of the geometrid sex pheromone components, as well as the distribution pattern of pheromone components among geometrid subfamilies, genera and species. The sex pheromone research situation of the important species in China was also discussed, which provides reference for subsequent researches on geometrid pheromone and effective green control of insect pests of Lepidoptera with sex pheromones.
Scientific notes
Recreational Motivations of Tourists Visiting the Simingshan National Forest Park
Zhou Bin, Lei Fengyao, Yu Hu, Zhang Yichi
2019, 55(5):  163-168.  doi:10.11707/j.1001-7488.20190518
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[Objective] The purpose of this study was to analyse the different recreational motivations of tourists visiting the Simingshan National Forest Park, with the aim of providing a scientific basis for recommendations to upgrade and transform tourist attractions.[Method] A questionnaire survey was conducted to investigate the recreational motivations bringing tourists to the Simingshan National Forest Park. SPSS 22.0 software was used to conduct descriptive statistical analysis, exploratory factor analysis, mean value calculation, independent sample t-test, and one-way ANOVA. AMOS 21.0 software was used to conduct confirmatory factor analysis.[Result] There were 5 recreational motivations among tourists visiting the Simingshan National Forest Park. Their mean values are as follows:educational(3.96), social (4.03), self-realization (3.86), healthy relaxation (4.37), and escape(3.79). These results showed a decreasing trend in motivations from healthy relaxation to social, and then educational, self-realization, and finally escape.There were significant differences in the number of tourists with different levels of education. Tourists with different occupations showed significant differences in educational, self-realization, and escape motivations; while visitors with different levels of household income displayed significant differences in educational, social, and health and relaxation motivations.[Conclusion] The motivation ‘health and relaxation’ obtained the highest overall responses from visitors, followed by ‘social’, ‘educational’, and ‘self-realization’, while ‘escape’ ranked last. While maintaining the ecological security of forest, it was suggested that the Simingshan National Forest Park develop forest tourism for health, research and education, vacations, recreation of the aged, forest-based sports, etc.
Analyses of Seed Development of Plukenetia volubilis by Joint Metabolomics and Transcriptomics Approaches
Liu Guo, Chen Hongpeng, Wu Zhihua, Peng Yan, Xie Yaojian
2019, 55(5):  169-179.  doi:10.11707/j.1001-7488.20190519
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[Objective] Plukenetia volubilis is an oleaginous plant that contains high content of unsaturated fatty acid in the seed oil. It is a potential economically efficient crop with great possibilities for industrialization. There is a significant research gap in regulatory mechanisms of oil synthesis, related key genes and biosynthetic pathways. Therefore, the study of the dynamic changes rule of lipid metabolites and related regulatory genes of fatty acid metabolism of P. volubilis seeds could lay the foundation for further study on raising seed oil yield and improving seed oil quality and provide a valuable example for efficient development and utilization of other woody oil plants.[Method] To investigate the dynamic changes of lipid metabolites content, and search for key genes related to biosynthesis and accumulation of lipid metabolites from differentially expressed genes, gas chromatography mass spectrometry based metabolomics approach and high-throughput sequencing technology platform were used to analyze the P. volubilis seeds collected at different growth stages:initial formation stage, early development stage, middle stage, later stage and maturation stage.[Result] The result of metabolism analysis showed that the high contents of α-linolenic acid and linoleic acid were mainly biosynthesized and accumulated at the seed maturation stage, and the contents of α-linolenic acid and linoleic acid could be the basis for identifying the slow and the rapid accumulation periods. Transcriptome analysis indicated that there were significant differences in gene expression between before and after the stage of seed maturation. The result of combined metabolomics and transcriptomics analysis turned out that the expression patterns of six key enzyme genes related to fatty acid biosynthesis and accumulation were significantly correlated with the biosynthesis and accumulation of fatty acids. And different members of a gene family showed differences and diversity of biological functions. Among them, FAD2-3, FAD7, FATA, KAS2, LACS2, LACS8 and SAD were positively correlated with the contents of total and main fatty acids, indicating that the expression of the seven genes could promote the biosynthesis and accumulation of fatty acids. Moreover, the genes of FAD2-2, KCS1, KCS10 and LACS1 were negatively correlated with the contents of total and main fatty acids, indicating that the expression of the three genes have an inhibitory effect on the biosynthesis and accumulation of fatty acids.[Conclusion] In the study, there were significant differences in the content of fatty acids and the expression of differentially expressed genes between before and after the stage of P.volubilis seed maturation. Based on the content changes of α-linolenic acid and linoleic acid, the seed development process could be divided into the periods of slow and rapid accumulation of fatty acids. We also explored the dynamic changes of the 6 key enzyme genes and correlation analysis in fatty acids biosynthesis. It was found that the expression patterns of key enzyme genes were significantly correlated to the synthesis and accumulation of fatty acids. Different members of the same gene family might have different biological functions. The results laid a theoretical foundation and provided alternative genes on improving the yield of P. volubilis seed oil and changing the composition of fatty acid by technologies of molecular biology.
Extraction of Stand Factors in UAV Image Based on FCM and Watershed Algorithm
Li Dan, Zhang Junjie, Zhao Mengxi
2019, 55(5):  180-187.  doi:10.11707/j.1001-7488.20190520
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[Objective] The purpose of the investigation and monitoring of forest resources is to identify and implement the quantity and quality of the national forest resources, macro grasp of the development and change of forest resources, and provide data support for the sustainable development of national forest resources, it is the foundation of the management of national forest resources.[Method] This paper takes the Pinus sylvestris var. mongolica plantation as the research object in the city forestry demonstration base of Northeast Forestry University, using the multi rotor unmanned aerial vehicle(UAV)DOM as the data source, applying FCM clustering algorithm, watershed segmentation algorithm and a series of digital image processing technologies such as morphological operation, threshold segmentation, image smoothing, gray image and binary, extracting the stand factors of Pinus sylvestris var. mongolica plantation. FCM clustering algorithm and threshold segmentation method is used to extract treetop markings, then the watershed segmentation algorithm is used to iterate the treetop image, and the single tree crown segmentation image is obtained. According to the result of single tree crown segmentation, the characteristics of single tree are extracted and then the value of each stand factor is calculated.[Result] In the module of forestland extraction, the greenness segmentation successfully separates the forestland from the non-forestland, according to the color characteristics of the image. It determines the range of the single tree crown segmentation. In the module of single tree crown segmentation, both threshold segmentation and FCM clustering algorithm can be used to extract the treetop markers from the forestland image effectively. It has achieved good segmentation effect that applying watershed segmentation algorithm based on marker to single tree crown segmentation, most of the single tree crowns are separated from each other, but some areas still have problem of less segmentation or over segmentation. The stand factors include canopy density, number density, average crown width, average DBH, average tree height and volume. The measurement accuracy of the canopy density is 96.67%, the measurement accuracy of the woodland area is 81.23%, the measurement accuracies of the stumpage number and average crown width are related to the treetop extraction method and the two parameters(the size of structural elements of morphological corrosion and the window size of median filter)in the watershed segmentation. Parameter combination experiments on two method of treetop extraction are carried out respectively, the result show that the measurement accuracies of the stand factors of the two treetop extraction method using the proper combination of parameters are all above 80%, the average measurement accuracies are all above 90%, the maximum average measurement accuracy of the threshold segmentation method is 94.49%, the maximum average measurement accuracy of the FCM clustering algorithm is 93.17%.[Conclusion] The method of forest resource investigation by using the orthoimage of artificial forest taken by UAV is presented in this paper, which embodies the information construction of forestry. The application of advanced computer science and technology and unmanned aerial vehicle technology to the traditional field of forestry has effectively improved the efficiency and accuracy of forest resource investigation. The method proposed in this paper is suitable for the extraction of the stand factors of high canopy density forest, and the measurement accuracy meets the actual demand.
Population Dynamic of Far Eastern Leopard(Panthera pardus orientalis) in Wangqing Nature Reserve Based on Infrared Camera Monitoring
Kong Weiyao, Sun Quan, Liu Xinxin, Qu Li, Wang Fuyou, Yao Mingyuan, Zou Hongfei
2019, 55(5):  188-196.  doi:10.11707/j.1001-7488.20190521
Abstract ( 260 )   HTML   PDF (2183KB) ( 500 )  
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[Objective] Far Eastern Leopard (Panthera pardus orientalis) disperses in the northernmost region and maintains the minimum population of Panthera pardus subspecies. It is evaluated as Critical Endangered in IUCN Red List. In this study, we analyzed long-term dynamic of population size and distribution of Far Eastern Leopard in Wangqing Nature Reserve and expected to provide scientific data for the protection of this endangered species.[Method] From Autumn 2013 to Autumn 2017, cameras were set up with a density of 1 pair per 3 km×3 km grid in the main leopard habitat in Wangqing Nature Reserve. The relative abundance indices (RAI) was used to calculate leopard abundance, the distribution area was defined by 99% kernel density contour, and individual was identified in Extract Compare software. The closure test, model selection and population estimation were performed for the data of effective monitoring period with CAPTURE software. The effective trapping area was estimated by projecting an 8 km radius buffer around each camera trap location. Then we calculated population density using effective trapping area.[Result]The RAI of leopard varied from 0.34 to 2.12 during 9 monitoring seasons. The distribution area of leopard was 201 km2 in Autumn 2013 and 992 km2 in Autumn 2017. A total of 9 individuals were identified, including 3 females, 3 males, 2 cubs and 1 unrecognizable. Both the value and the power of CAPTURE closure test were low when population size was small. The model selection criterions of Mh (heterogeneity effects model) were highest in 4 monitoring seasons, and second only after M0 (null model) in the other 5 seasons. The goodness of fit tests of M0 vs Mb(behaviour effects model) and M0 vs Mt(time effects model)showed that there were no significant differences between groups. The population density of leopard ranged from 0.12 to 0.88 individual per 100 km2 during research period. The value of captured individual/estimated population size was relatively high in general, albeit there was a low value of 0.43 in Spring 2017.[Conclusion] The distribution pattern of leopard obviously showed spatiotemporal heterogeneity due to geographic variance and prey abundance fluctuation. CAPTURE closed population test was ineffective for small sample test. Mh model was proper to evaluate leopard population. The capture rates showed no variance after trap or in different trap occasions. Leopard population density would be overestimated due to trap-shy response.