609 results
Search Results
2. [Global quantification of the spatial variability and temporal stability of throughfall].
- Author
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Wang Q, Yuan C, Zhang YF, Hu YT, Wang Y, Guo L, Liu Q, and Cai ZY
- Subjects
- China, Climate, Spatio-Temporal Analysis, Ecosystem, Rain, Trees growth & development
- Abstract
Spatial variability of throughfall ( i.e. the non-uniform characteristics of throughfall at different canopy positions) and its temporal persistence ( i.e. time stability) are related to the quantity and efficiency of soil moisture replenishment, and affect plant competition and community succession dynamics by affecting resource availability. We carried out a meta-analysis with 554 papers (from 2000 to 2022) retrieved from Web of Science and China National Knowledge Infrastructure (CNKI) based on keyword search, quantified and compared the amount, spatial heterogeneity, and temporal stability characteristics of penetrating rain in different climate zones and plant functional types. Our results that throughfall proportion was lower in arid regions (72.0%±13.6%) than humid (75.1%±9.3%) and semi-humid areas (79.9%±10.4%). Cold climates had lower values (74.1%±14.6%) than temperate (74.2%±7.5%) and tropical climates (80.9%±14.6%). Shrubs (68.9%±14.9%) generally had lower throughfall proportion than trees (76.7%±9.1%). Broad-leaved trees (75.2%±11.1%) and conifers (75.1%±9.9%) showed similar throughfall proportions, as did evergreen (76.7%±10.0%) and deciduous species (74.7%±11.9%). Additionally, spatial variability (coefficient of variation) did not significantly differ across rainfall zones, temperature zones, or vegetation types. The spatial distribution of throughfall was relatively stable. Canopy structure was the dominant factor affecting temporal stability of throughfall. However, there was a lack of comparison between typical geographic units ( i.e. spatial units with basically consistent geographical environmental conditions) at various temporal scales. Future research should expand upwards to the summary of global spatial scale rules and downwards to the analysis of process based temporal scale mechanisms, to depict the dynamic distribution of penetrating rain and unify observation standards to enhance comparability of different studies, in order to efficiently promote research on canopy penetrating rain and provide ecological and hydrological basis for protecting nature, managing artificial activities, and restoring degraded ecosystems.
- Published
- 2024
- Full Text
- View/download PDF
3. [Meta-analysis of plant restoration impacts on soil microbial community structure in mining areas].
- Author
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Wang YQ, Yuan CX, Yue K, Wu FZ, Yuan J, Zhao ZM, and Peng Y
- Subjects
- China, Environmental Restoration and Remediation methods, Soil chemistry, Trees growth & development, Nitrogen analysis, Bacteria classification, Bacteria growth & development, Biomass, Plants, Conservation of Natural Resources, Soil Microbiology, Mining, Ecosystem
- Abstract
Mining causes severe damage to soil ecosystems. Vegetation restoration in abandoned mine areas is an inevitable requirement for sustainable development. Soil microbes, as the most active component of soil organic matter, play a crucial role in the transformation of carbon, nitrogen, phosphorus, and other elements. They are often used as indicators to assess the extent of vegetation restoration in ecologically fragile areas. However, the impacts of vegetation restoration on soil microbial community structure in mining areas at the global scale remains largely unknown. Based on 310 paired observations from 44 papers, we employed the meta-analysis approach to examine the influence of vegetation restoration on soil microbial abundance and biomass in mining area. The results indicated that vegetation restoration significantly promotes soil microbial biomass in mining areas. In comparison to bare soil, vegetation restoration leads to a significant 95.1% increase in soil microbial biomass carbon and a 87.8% increase in soil microbial biomass nitrogen. The abundance of soil bacteria, fungi, and actinomycetes are significantly increased by 1005.4%, 472.4%, and 177.7%, respectively. Among various vegetation restoration types, the exclusive plan-ting of trees exhibits the most pronounced promotion effect on soil microbial biomass and population, which results in a significant increase of 540.3% in soil fungi and 104.5% in actinomycetes, along with a respective enhancement of 110.3% and 106.4% in microbial biomass carbon and nitrogen. Model selection results revealed that soil satura-ted water content and vegetation restoration history contribute most significantly to the abundance of soil bacteria and fungi. Soil available nitrogen has the most significant impact on the abundance of actinomycetes and microbial biomass carbon, while soil available phosphorus emerges as a crucial factor affecting microbial biomass nitrogen. This research could contribute to understanding the relationship between vegetation restoration and the structure of soil microbial communities in mining areas, and providing scientific support for determining appropriate vegetation restoration types in mining areas.
- Published
- 2024
- Full Text
- View/download PDF
4. [Effects of leaf extracts of Amorpha fruticosa on seed germination and seedling growth of Amygdalus pedunculata ].
- Author
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Wang XQ, Wang JX, Ma X, Zhang YY, Wang HB, Wang YB, and DI L
- Subjects
- Animals, China, Germination, Plant Extracts, Seedlings, Seeds, Fabaceae, Thoracica
- Abstract
Amorpha fruticosa and Amygdalus pedunculata are common plant species used for greening construction in arid and semi-arid region of Northwest China. In order to explore the feasibility of greening construction and ecological restoration by A. fruticose with A. pedunculata , we exami-ned the allelopathic effects of five concentrations of aqueous leaf extracts of A. fruticosa (0.025, 0.05, 0.10, 0.15 and 0.20 g·mL
-1 ) on eight A. pedunculata varieties (YY1 , YY3 , YY4 , YY5 , YY6 , SM6 , SM7 and SM8 ), using the methods of paper-petri dish and soilless culture. The results showed that when the concentration of A. fruticosa leaf extracts were 0.025 and 0.05 g·mL-1 , the seed germination and seedling growth of YY1 and SM6 were significantly better than other varieties. With increasing concentration of A. fruticosa leaf extracts, the catalase activity of A. pedunculata seedlings first increased and then decreased. The activities of peroxidase and superoxide dismutase, and the contents of soluble protein and chlorophyll showed a downward trend, while the contents of malondialdehyde and soluble sugar and the permeability of cell membrane gradually increased. Results of the principal component and cluster analysis showed that the growth potential of A. pedunculata decreased with the order of YY1 , SM6 , SM8 , SM7 , YY6 , YY3 , YY5 and YY4 under the allelopathic effect of A. fruticose . In conclusion, the artificial collocation and mixed planting of low-density of A. fruticosa with YY1 and SM6 were beneficial to seed germination and seedling growth of A. pedunculata .- Published
- 2021
- Full Text
- View/download PDF
5. [Representation, analysis and application of landscape graph based on graph theory].
- Author
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Song LL, Qin MZ, Zhang PY, Xia YF, Ma J, and Cao W
- Subjects
- Animals, Biodiversity, Canada, China, Ecology, Conservation of Natural Resources, Ecosystem
- Abstract
Landscape structure and spatial pattern are the core issues in landscape ecology. The application of graph theory provides a research framework for landscape pattern analysis. Landscape graph based on graph theory is gradually applied to the connectivity modeling of biodiversity conservation and decision support of landscape planning. The representation, analysis and application of landscape graph have become a hot topic in conservation biology and landscape ecology. In this review, we first introduced the graph theory basis of landscape map. Based on the Scopus database, 257 published journal papers with the words "landscape graph", "connectivity" and "network" in titles, abstracts, and keywords from 1993 to 2019 were retrieved. We analyzed the research progress and development trend of this field from the aspects of annual published papers, journal sources, research areas, research institutions and landscape types involved. The results showed that before 2017, the number of journal papers published showed an overall increasing trend, and after 2017, the annual number of published papers decreased year by year. The main research forces were concentrated in United States, France, Canada, and China, contributing to 86.8% of the total published papers. Most of the research results were published in "Landscape Ecology", "Landscape and Urban Planning", and "Biological Conservation". In the research content, the representation of landscape graph mainly included the definition of nodes, the measurement of edges and the simulation of landscape. The analysis of landscape graph involved analysis index and landscape graph partitioning. This study mainly focused on the application of landscape graph in science and practice, including biodiversity conservation, landscape (ecological network) planning and management, the assessment of landscape impacts. Landscape graph based on graph theory influences conservation science and planning practitioners by helping understand landscape connectivity changes, animal behavior and habitat conservation. The impact of graph theory on conservation science and planning comes from the rich theoretical basis and mature research methods. Landscape graph based on graph theory provides a springboard for ecological understanding of landscape structure and pattern, and is an important tool for global researchers and practitioners.
- Published
- 2020
- Full Text
- View/download PDF
6. [Characteristics of evapotranspiration in an alpine shrub meadow in Haibei, Qinghai of Northwest China].
- Author
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Zheng H, Wang QF, Li YN, and Zhu XJ
- Subjects
- Altitude, China, Environmental Monitoring, Volatilization, Cold Temperature, Ecosystem, Plant Transpiration, Poaceae physiology, Water Movements
- Abstract
Evapotranspiration (ET) is an important component of hydrological cycle of terrestrial ecosystem. To study the seasonal and interannual ET variation patterns of typical ecosystems is essential to better understand the water cycle process and to provide reference for the rational utilization of water resources. By using eddy covariance method, this paper studied the seasonal and interannual variation characteristics of ET and water budget in an alpine shrub meadow ecosystem in Haibei of Qinghai from 2003 to 2011. There was an obvious seasonal variation of ET in the study area in 2003-2011, with the maximum (4.4-5.7 mm x d(-1)) in the vigorous growth season (July-August) and the minimum (0.09 +/- 0.04 mm x d(-1)) in January or December. The annual ET varied greatly among the nine consecutive years, being 451.3 mm in 2010 and 681.3 mm in 2007. More than 70% of the annual ET occurred in the growth season from May to September. The average ratio of annual ET to annual precipitation was 1.06 +/- 0.17, indicating that the water budget of this ecosystem was nearly balanced at year scale, and almost all the precipitation was released into atmosphere by ET.
- Published
- 2013
7. [Spatiotemporal variation and related affecting factors of Gloiopeltis furcata biomass and length around Xiaoheishan Island, Shandong of China].
- Author
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Liu HL, Tang YZ, Yu YQ, Li XM, and Zhang QS
- Subjects
- China, Oceans and Seas, Rhodophyta physiology, Seasons, Spatio-Temporal Analysis, Biomass, Ecosystem, Rhodophyta growth & development, Seawater
- Abstract
Gloiopeltis furcata, an important economic red macroalga, has been severely depleted due to human disturbances. Taking the natural G. furcata populations around the Xiaoheishan Island of Shandong, China as test objects, this paper studied the spatiotemporal variation pattern of their biomass and length and related affecting factors. The two-way ANCOVA showed that at island scale, both the subbottom and the Baardseth index had significant effects on the G. furcata biomass and length. The steady subbottom and the high Baardseth index were beneficial to the G. furcata growth. At micerohabitat scale, wave action and tidal level had significant effects on the G. furcata biomass and length. Wave wash and moderate tidal level promoted the G. furcata growth. The one-way repeated measurements ANOVA showed there existed seasonal variation of G. furcat biomass and length. The optimal growth period of G. furcata was from March to April, with the peak values of biomass and length appeared in late spring and early summer.
- Published
- 2013
8. [Polypore diversity in main natural larch forests in China].
- Author
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Wu B and Wei YL
- Subjects
- China, Larix growth & development, Polyporus growth & development, Biodiversity, Forests, Larix microbiology, Polyporus classification
- Abstract
Larch is the important coniferous species in Northern China. Many polypore species are growing on the fallen trunks of natural larch forests, which can decompose the cellulose, semi cellulose, and lignin of the fallen trunks, and promote the matter cycling and maintain the carbon balance in forest ecosystem, playing a key ecological function in forest ecosystem. Aiming at the polypore species on the 5 main larch forest species in China, this paper analyzed the species composition and distribution characteristics of polypore, and compared the polypore species diversity on different kinds of larch in China. A total of 107 polypore species were recorded, belonging to 43 genera in 11 families, among which, brown fungi accounted for 45.4% of the total collected in this study, and occupied about 50% of the whole brown fungi reported in China. 91. 7% of the polypore grew on the decaying fallen trunk. Larix gmelini had more polypore species and individuals, as compared with the other 4 larch species. There was a high similarity in the polypore community composition on L. gmelini and L. olgensisi and on L. sibirica and L. griffithiana, which was in accordance with the natural distribution of related forests.
- Published
- 2013
9. [Effects of different drip irrigation modes on root distribution of wine grape 'Cabernet Sauvignon' in desert area of Northwest China].
- Author
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Mao J, Chen BH, Cao JD, Wang LJ, Wang H, and Wang YX
- Subjects
- China, Ecosystem, Agricultural Irrigation methods, Desert Climate, Plant Roots growth & development, Vitis growth & development
- Abstract
To study the effects of different drip irrigation modes on the wine grape root distribution is the basis of formulating fertilization, irrigation, and over-wintering management practices for wine grape. Taking the wine grape "Cabernet Sauvignon" as test material, this paper studied the effects of different water-saving irrigation modes (drip irrigation under straw mulching, drip irrigation under plastic mulching, double-tube drip irrigation, and single-tube drip irrigation) on the root distribution of wine grape in the desert area of Northwest China, with the conventional furrow irrigation as the control. The root system of the "Cabernet Sauvignon" was distributed from 0 to 70 cm vertically, and from 0 to 120 cm horizontally. With double-tube drip irrigation, the root amount was the largest (138.3 roots per unit profile), but the root vertical distribution scope was narrowed by 20 cm, as compared to the control. Drip irrigation with straw mulching increased the root amount significantly, and increased the root horizontal distribution scope by 9.1%, as compared to the control. No significant difference was observed in the root number and root horizontal distribution scope between the drip irrigation under plastic mulching and the control, but the root vertical distribution scope with the drip irrigation under plastic mulching decreased by 20 cm. Single-tube drip irrigation increased the root number significantly, but had lesser effects on the root vertical or horizontal distribution, as compared to the conventional irrigation. It was suggested that the drip irrigation under straw mulching could be the best water-saving practice for the wine grape "Cabernet Sauvignon" in the study area.
- Published
- 2013
10. [Climatic suitability model for spring maize in Northeast China].
- Author
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Hou YY, Zhang YH, Wang LY, Lü HQ, and Song YB
- Subjects
- China, Seasons, Climate, Ecosystem, Models, Theoretical, Zea mays growth & development
- Abstract
Crop growth is a continuous and dynamic process, and thus, the optimal meteorological indices for crop growth also change continuously. In this paper, the estimation algorithms of the daily available precipitation and the temporal interpolation methods of meteorological indices for crop growth were developed, and the climatic suitability model at daily scale was established, which was tested by the spring maize data of agro-meteorological stations in Northeast China. The simulated climatic suitability had significantly positive correlations with the height and 100-grain mass of spring maize. The correlation coefficient (R2) between the climatic suitability and the spring maize height was over 0.58 at vegetative growth stage, and over 0.45 at reproductive growth stage. The established climatic suitability model at daily scale could objectively reflect the interactions between crop growth and meteorological factors at vegetative growth stage and reproductive growth stage.
- Published
- 2013
11. [Area changes of emergent herbaceous wetlands in relation to water level in East Dongting Lake, China in 1989-2011].
- Author
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Tang Y, Xie YH, Li F, and Chen XS
- Subjects
- China, Lakes, Fresh Water analysis, Remote Sensing Technology methods, Water Movements, Wetlands
- Abstract
Based on multi-temporal Landsat MSS/TM/ETM+ images, and by using decision tree method, this paper extracted the areas of emergent herbaceous wetlands with different water levels in 1989-2011 in the East Dongting Lake, China. The change characteristics and change trends of the emergent herbaceous wetlands areas were investigated based on the DEM data and the daily water level data from the Chenglingji Hydrological Station. The area of the emergent herbaceous wetlands was significantly affected by water level (R2 = 0.875, P < 0.001), presenting a significant linear relationship between the two. Moreover, the emergent herbaceous wetlands area decreased with increasing water level. The higher the water level, the smaller the effects of the water level on the emergent area were. The emergent area changed regularly with water level. In January-July, water level increased, and the emergent area decreased; in July-December, it was opposite. In 1989-2011, the areas of emergent herbaceous wetlands had a continual increase. The newly emergent herbaceous wetlands area was mainly transformed from mudflat. The emergent herbaceous wetlands expansion was the co-effects of the increase of the emergent herbaceous wetlands areas at different elevations, and the rapid expansion of the emergent herbaceous wetlands in low bottomland (22-25 m of Yellow Sea elevation) played the most important role in the expansion. The change of water level at different elevations was the dominant cause for the changes of emergent herbaceous wetlands areas in the East Dongting Lake in the past 20 years.
- Published
- 2013
12. [Simulation of leaf inclination angle distribution of main tree species in Daxing'an Mountains of China based on the Campbell ellipsoid distribution function].
- Author
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Wang XP, Fan WY, and Wen YB
- Subjects
- Betula anatomy & histology, China, Computer Simulation, Ecosystem, Pinus anatomy & histology, Remote Sensing Technology methods, Models, Theoretical, Plant Leaves anatomy & histology, Plant Leaves radiation effects, Trees anatomy & histology
- Abstract
Leaf inclination angle distribution directly decides the amount of radiation interception by vegetation canopy, and also, decides the size and direction of the incident radiation, being the key parameter in quantitative remote sensing. This paper simulated the leaf inclination angle distribution of the main tree species in Daxing'an Mountains forest region based on the Campbell ellipsoid distribution model and iterative method, and quantitatively analyzed the fitting results of canopy with and without leaf stratification as well as the effects of tree age group on the leaf inclination angle distribution. For the test 6 main tree species, the leaf inclination angle distribution was in planophile shape, and the mean leaf inclination angle was smaller for coniferous tree than for broadleaved tree. Whether with or without stratify, the fitting result and the measured result were basically identical. For Betula platyphylla and Larix gmelinii, the correlation coefficient between the simulated and measured values was 0.8268 and 0.8192, and the root mean square error was 3.7% and 4.3% respectively, indicating that the Campbell model was reliable applied for forest canopy. Considering the effects of tree age group, though the leaf inclination angle distribution trend with leaf stratification had no correlation with age group, the mean leaf inclination angle of young L. gmelinii was relatively smaller than that mature one, suggesting that age group had positive effects on the numerical design of leaf inclination angle distribution and negative effects on the numerical design of extinction coefficient.
- Published
- 2013
13. [Multi-scale and multi-parameter spatial distribution patterns of Seriphidium terrae-albae and Artemisia songarica populations in Gurbantunggut Desert of Northeast China].
- Author
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Ye T, Yuan-Ming Z, and Xiao-Bo W
- Subjects
- Artemisia classification, China, Desert Climate, Population Dynamics, Artemisia growth & development, Asteraceae growth & development, Conservation of Natural Resources, Ecosystem
- Abstract
The researches on the plant population spatial pattern were mostly based on 0-D plant point (0-D IND) or 0-D plant count, and only a few was based on the 2-D projective cover (2-D PC) and 3-D aboveground biomass (3-D AGB reflected by canopy volume). Until now, the plant population spatial distribution patterns incarnated by these parameters were still unclear. Taking the widely distributed small semi-shrubs Seriphidium terrae-albae and Artemisia songarica in Gurbantunggut Desert of Northwest China as test objects, this paper studied the IND, PC, and AGB of each individual at two sampling plots. Through six-scale division of plot coordinate system with GIS, and by using aggregation analysis, coefficient of variation (CV) , and a scaling exponent between the CV and six scales, the characteristics of the population spatial distribution patterns with the above mentioned parameters were comparatively analyzed. At all scales, the IND (except for the S. terrae-albae population at 0.5 m scale) and the AGB of the two shrubs all presented a clumped distribution, and the aggregation intensity increased' with increasing scale. However, the PC had a uniform distribution (except for the A. songarica population at 5 and 8 m scales). With increasing scale, the CV values of the two shrubs decreased. The absolute value of scaling exponent (k value) of the IND was higher than those of the PC and AGB, and there was no significant difference in the k values between the PC and AGB, indicating that the scale variation scope of the struc- tural complexity of the IND was larger than that of the PC and AGB. The k value of each parameter for S. terrae-albae was higher than that for A. songarica, which could be related to the populations' interspecific relationship and plant size. In sum, the IND and AGB had similar spatial patterns, while the PC and AGB had almost same spatial pattern complexity and scale change characteristics.
- Published
- 2013
14. [Spatial variation of non-structural carbohydrates in Betula platyphylla and Tilia amurensis stems].
- Author
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Zhang HY, Wang CK, Wang XC, and Cheng FY
- Subjects
- China, Betula chemistry, Carbohydrates analysis, Plant Stems chemistry, Tilia chemistry
- Abstract
Taking the two diffuse-porous tree species Betula platyphylla and Tilia amurensis in a temperate forest in Northeast China as test objects, this paper studied the spatial variation of the non-structural carbohydrates (NSC) concentrations in the stem xylem after leaf-fall. For the two tree species, the concentrations of total non-structural carbohydrate (TNC, soluble sugars plus starch) and soluble sugars in the stem xylem decreased gradually with the increasing depth from cambium to pith, whereas the starch concentration showed little radial variation. There was still a substantial amount of NSC in the inner wood close to pith. The concentrations of the NSC in the two species stems decreased gradually from the stump to the breast height, and then increased vertically. The maximum concentrations of the TNC, soluble sugars, and starch occurred at different heights, depending on the species and the TNC components. The ratio of sugar to starch showed a contrasting vertical trend for the two species, i. e., increasing from the stump to the top for B. platyphylla, but decreasing for T. amurensis. The estimation error of the stem NSC storage was mainly from the axial variation, and then, from the radial variation of NSC concentration. The TNC concentration (1.0% dry mass) in the stem of shade-intolerant species B. platyphylla was significantly lower than that (4.3% dry mass) of shade-tolerant species T. amurensis, which could be related to their different life-history strategies. Applying the sampling protocols considering the axial and radial variations of NSC could effectively reduce the potential uncertainty in estimating the NSC storage at tree or stand level.
- Published
- 2013
15. [Photosynthetic and water physiological characteristics of weedy rice in northern China].
- Author
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Gao Q, Ma DR, Kong DX, Wang WJ, Tong H, Zhao MH, Xu ZJ, and Chen WF
- Subjects
- China, Ecosystem, Genetic Variation, Oryza classification, Oryza physiology, Photosynthesis physiology, Water physiology
- Abstract
Weedy rice is an important germplasm source of rice, which has the characteristics of cold-, drought-, and barren tolerance. Taking 88 accessions of weedy rice and 4 varieties of cultivated rice in northern China as test materials, this paper studied the photosynthetic characteristics (photosynthetic rate, transpiration rate, and stomatal conductance), water physiological characteristics, and their interrelationships of weedy rice in northern China. There existed greater differences in the photosynthetic and water physiological characteristics among the weedy rice accessions, possessing abundant diversity. The photosynthetic rate of the accessions was from 12.47 micromol CO2 x m(-2) x s(-1) to 28.67 micromol CO2 X m(-2) x s(-1), and the instantaneous water use efficiency was from 1.39 mg x g(-1) to 3.40 mg x g(-1). Among the photosynthetic parameters, intercellular CO2 concentration had the smallest variable coefficient, while stomatal conductance had the largest one. The photosynthetic rate had significant conic relationships with transpiration rate and stomatal conductance, and had a linear relationship with intercellular CO2 concentration. The significant conic relationships also existed between the instantaneous water use efficiency and the transpiration rate and stomatal conductance. The excellent features of weedy rice could be used to improve the cultivated rice varieties.
- Published
- 2013
16. [Estimation of carbonaceous gases emission from forest fires in Xiao Xing'an Mountains of Northeast China in 1953-2011].
- Author
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Hu HQ, Luo BZ, Wei SJ, Sun L, Wei SW, and Wen ZM
- Subjects
- Carbon Monoxide analysis, China, Environmental Monitoring, Forests, Gases analysis, Carbon analysis, Carbon Dioxide analysis, Fires, Methane analysis, Trees classification
- Abstract
Based on the forest resources investigation data and the forest fire inventory in 1953-2011, in combining with our field research in burned areas and our laboratory experiments, this paper estimated the carbonaceous gases carbon dioxide (CO2), carbon monoxide (CO), methane (CH4), and nonmethane hydrocarbons (NMHC) emission from the forest fires in Xiao Xing' an Mountains of Heilongjiang Province, Northeast China in 1953-2011. The total carbon emission from the forest fires in the Xiao Xing'an Mountains in 1953-2011 was 1.12 x 10(7) t, and the annual emission was averagely 1.90 x10(5) t, accounting for 1.7% of the annual average total carbon emission from the forest fires in China. The emission of CO2, CO, CH4, and NMHC was 3.39 x 10(7), 1.94 x 10(5), 1.09 x 10(5), and 7.46 x 10(4) t, respectively, and the corresponding annual average emission was 5.74 x 10(5), 3.29 x 10(4), 1.85 x 10(3), and 1.27 x 10(3) t, accounting for 1.4%, 1.2%, 1.7%, and 1.1% of the annual carbonaceous gases emitted from the forest fires in China, respectively. The combustion efficiency and the carbon emission per unit burned area of different forest types decreased in order of coniferous forest > broad-leaved forest > coniferous broadleaved mixed forest. Some rational forest fire management measures were put forward.
- Published
- 2013
17. [Species composition and main populations spatial distribution pattern in Korean pine broadleaved forest in Xiaoxing' An Mountains of Northeast China].
- Author
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Hou HY and Wang LH
- Subjects
- Abies growth & development, China, Pinus anatomy & histology, Population Dynamics, Spatial Analysis, Tilia growth & development, Trees growth & development, Conservation of Natural Resources, Forests, Pinus growth & development, Trees classification
- Abstract
Taking the Korean pine broadleaved forest in Liangshui Nature Reserve of Heilongjiang Province, Northeast China as test object, this paper studied the species composition and diameter class structure, and by using point pattern analysis, analyzed the spatial distribution pattern and spatial association of the main populations. In the Reserve, there were a total of 16 species with diameter greater than 1 cm in tree layer, and great differences were observed in the densities of main populations. Coniferous trees such as Pinus koraiensis and Abies nephrolepis were dominant. The diameter class structure of the populations presented as an inverse "J" curve, indicating a good regeneration across the community. The main populations were mostly in aggregated distribution pattern, except that the P. koraiensis populations at the scales of 19-21 m and 44 m as well as the Acer tegmentosum populations close to the largest research scale were in random distribution. The P. koraiensis populations at all research scales were approximately in random distribution, and had the minimum aggregation. A. nephrolepis, Tilia amurensis, and A. tegmentosum populations all presented a random distribution trend. Except that the P. koraiensis and A. nephrolepis at 2-3 m scale and the A. nephrolepis and A. tegmentosum populations at 37-81 m scale had significant positive association, no significant associations were observed between other populations. All the tree species presented an overall non-significant positive association.
- Published
- 2013
18. [Yield formation of different single-season rice (Oryza sativa L. ) types and its relationships with meteorological factors in Yunnan Province of Southwest China].
- Author
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Zhong C, Zhu YM, Zhu Y, Zhu B, Zhang MS, and Xu MY
- Subjects
- China, Biomass, Ecosystem, Meteorological Concepts, Oryza growth & development
- Abstract
By using the 1994-2010 observation data of paddy rice growth period and yield from 14 agro-meteorological stations at different altitudes in Yunnan Province, this paper studied the rice yield formation and the effects of meteorological factors on low-yield rice yield components. According to the systematic cluster analysis of rice yield components and the rice types at the 14 stations, the rice was divided into 4 types, i. e., low-yield japonica rice, low-yield indica rice, high-yield japonica rice, and high-yield indica rice. The analysis of the yield components of the 4 rice types showed that there was a significant positive correlation between the spikelet number per square meter (sqm) and the rice yield. The yield of low-yield japonica was mainly affected by the seed setting rate and the spikelet number per sqm. For the other three rice types, the spikelet number per sqm had greater effects on the rice yield. The low-yield japonica rice was mainly affected by low temperature. At booting stage, low temperature decreased the spikelet number and the productive panicle number of unit sqm. At booting and flowering stages, low temperature increased the empty grain rate, and the effects of average temperature, average maximum temperature, and cold accumulated temperature were greater. At pre-milk stage, low temperature increased the unfilled grain rate, and meanwhile, decreased the 1000-grain mass. The yield components of low-yield indica rice were obviously affected by multiple meteorological factors. A certain degree of warming at tillering and jointing stages was not beneficial to the increase of productive panicle number per sqm of low-yield indica rice, but the more sunshine hours and the greater average diurnal temperature range at tillering stage was beneficial to the increase of the productive panicle number per sqm. There was a parabolic relationship between the temperature and sunshine hours at tillering and jointing stages and the spikelet number per panicle. The low temperature at flowering stage affected the empty grain rate of low-yield indica rice to a certain extent, while the high temperature and less rain at pre-milk stage not only increased the unfilled grain rate, but also distinctly reduced the 1000-grain mass.
- Published
- 2013
19. [Ecological function evaluation and related management strategies of river ecosystem in Taizi River basin, North China].
- Author
-
Liu HY, Zhang Y, Ma SQ, and Meng W
- Subjects
- Animals, China, Ecology organization & administration, Aquaculture methods, Aquatic Organisms classification, Biodiversity, Ecology methods, Ecosystem, Rivers
- Abstract
By the method of index evaluation at reach scale, this paper evaluated the ecological functions of aquatic biodiversity maintenance, habitat maintenance, water quality sustainment, and hydrological support of the river system in Taizi River basin of North China. The dominant ecological functions and the total ecological function were determined after sorting and summing. All the reaches in the basin were divided into four hierarchies of ecological functions. Overall, the total ecological function showed a spatially degrading trend from the mountainous region to the plain. Based on the evaluation results of the total function and dominant functions, six ecosystem management strategies were proposed. For the reaches with the functions of aquatic biodiversity- and habitat maintenance, the primary ecological management strategies included ecological conservation, ecological maintenance, and ecological restoration; for the reaches with the functions of water quality sustainment and hydrological support, the primary strategies of ecological management included limited development, development optimization, and exploitation.
- Published
- 2013
20. [Simulation of water and carbon fluxes in harvard forest area based on data assimilation method].
- Author
-
Zhang TL, Sun R, Zhang RH, and Zhang L
- Subjects
- Algorithms, China, Computer Simulation, Trees growth & development, Carbon metabolism, Forestry economics, Forests, Trees metabolism, Water metabolism
- Abstract
Model simulation and in situ observation are the two most important means in studying the water and carbon cycles of terrestrial ecosystems, but have their own advantages and shortcomings. To combine these two means would help to reflect the dynamic changes of ecosystem water and carbon fluxes more accurately. Data assimilation provides an effective way to integrate the model simulation and in situ observation. Based on the observation data from the Harvard Forest Environmental Monitoring Site (EMS), and by using ensemble Kalman Filter algorithm, this paper assimilated the field measured LAI and remote sensing LAI into the Biome-BGC model to simulate the water and carbon fluxes in Harvard forest area. As compared with the original model simulated without data assimilation, the improved Biome-BGC model with the assimilation of the field measured LAI in 1998, 1999, and 2006 increased the coefficient of determination R2 between model simulation and flux observation for the net ecosystem exchange (NEE) and evapotranspiration by 8.4% and 10.6%, decreased the sum of absolute error (SAE) and root mean square error (RMSE) of NEE by 17.7% and 21.2%, and decreased the SAE and RMSE of the evapotranspiration by 26. 8% and 28.3%, respectively. After assimilated the MODIS LAI products of 2000-2004 into the improved Biome-BGC model, the R2 between simulated and observed results of NEE and evapotranspiration was increased by 7.8% and 4.7%, the SAE and RMSE of NEE were decreased by 21.9% and 26.3%, and the SAE and RMSE of evapotranspiration were decreased by 24.5% and 25.5%, respectively. It was suggested that the simulation accuracy of ecosystem water and carbon fluxes could be effectively improved if the field measured LAI or remote sensing LAI was integrated into the model.
- Published
- 2013
21. [Effects of biochars produced from different sources on arsenic adsorption and desorption in soil].
- Author
-
Guan LZ, Zhou JJ, Zhang Y, Zhang GC, Zhang JH, and Chan ZX
- Subjects
- Adsorption, Animals, Biodegradation, Environmental, Cattle, China, Manure, Arsenic chemistry, Charcoal chemistry, Soil Pollutants chemistry
- Abstract
By using OECD Guideline 106 batch equilibrium method, this paper studied the characteristics of As (V) adsorption and desorption in brown soil as affected by the biochars produced from dairy manure, pine needle, and corn straw. When the addition amount of the biochars was 0.5%, the maximum adsorption amount of As (V) was decreased in the order of dairy manure biochar > pine needle biochar > corn straw biochar, which was related to the basic characteristics of the biochars. The adsorption isotherm of As (V) could be well fitted by Langmuir model (R2 = 0.997). In comparing with CK, both the adsorption capacity (lgKf = 1.99-2.10) and the adsorption intensity (1/N = 0.413-0.449) of As (V) were low, and the main adsorption mechanism was physical adsorption. The desorption rate of As (V) (14.5%-18.7%) was decreased in the order of dairy manure biochar > pine needle biochar > corn straw biochar. The addition of the biochars decreased the adsorption of As (V) by brown soil, which could induce the increase of the bioavailability of As, and strengthen the toxicity of As in soil.
- Published
- 2013
22. [Experiment precision and comprehensive environmental evaluation of regional wheat trials in rainfed regions of China].
- Author
-
Chang L, Han FX, Chai SX, Yue Y, Yang DL, Yang CG, Huang CX, and Cheng HB
- Subjects
- China, Genotype, Rain, Seasons, Temperature, Triticum genetics, Biomass, Droughts, Ecosystem, Gene-Environment Interaction, Triticum growth & development
- Abstract
Based on the grain yield data of regional trials with 233 winter- and spring wheat cultivars (lines) in rainfed farmlands at 82 locations in four subregions of China in 2003-2009, this paper studied the experiment precision (EP), variety comparison precision (VCP), and testing-site discrimination ability and representativeness of national regional trials, and comprehensively evaluated the trial environment. The results showed that in one-location-one-year experiments, the average coefficient of variation (CV) and the relative least significant difference (RLSD) were 6.1% and 10.5%, respectively, and in multi-location-one-year experiments, the CV was all within 8.2%, and the CV and RLSD were mostly well controlled, indicating that the trials had a high precision. The testing-site discrimination ability was the highest in the northwest spring wheat subregion, but showed less difference in the other subregions. The testing-site representativeness was the best in the northeast spring wheat subregion, and the worst in the northwest spring wheat subregion. On the basis of the comprehensive consideration of the testing-site discrimination ability and representativeness, and by using the parameters of the environmental comprehensive assessment (r(g)h) of GGE model, it was shown that the proportion of the ideal trial locations for wheat in our rainfed farmlands was only 32.4%. Among the wheat production regions, the proportions of the ideal trial locations were in the order of northwest spring wheat subregion (40.9%) > northeast spring wheat subregion (33.3%) > Huang-Huai winter wheat subregion (30.4%) > north winter wheat subregion
- Published
- 2013
23. [Runoff process in forested basin of Hun River-Taizi River, Northeast China: a simulation study].
- Author
-
Cai YC, Jin CJ, Wang AZ, Guan DX, Wu JB, and Yuan FH
- Subjects
- China, Computer Simulation, Ecosystem, Models, Theoretical, Rivers, Water Movements, Hydrology, Rain, Trees growth & development
- Abstract
Based on the hydrological data from the Beikouqian and Nandianyu stations in the upstream of Hun River and Taizi River as well as the meteorological data from the Qingyuan, Xinbin, and Benxi County stations, Northeast China in 1998-2007, a distributed hydrological model (DHS-VM) was applied to simulate the hydrological process in Hun-Tai basin. The scientific applicability of the model was validated, and the reference values of the most sensitive model parameters were provided. The simulated monthly runoff Nash-Suttclife coefficient (E value) for the source region of Hun River in calibration period (1998-2002) and validation period (2003-2007) was 0.9675 and 0. 8957, respectively, which could better reappear the monthly runoff process in this source region. The simulated monthly and annual runoff E values for the upstream of Taizi River were greater than 0.6, indicating that this model had good applicability in Hun-Tai basin, and the calibrated parameter scheme had a good reliability. This paper established a solid framework for the hydrological study over ungauged basin, and constructed a reasonable parameter scheme.
- Published
- 2013
24. [Characteristics and adaptation of seasonal drought in southern China under the background of climate change. V. Seasonal drought characteristics division and assessment in southern China].
- Author
-
Huang WH, Sui Y, Yang XG, Dai SW, and Li MS
- Subjects
- China, Disasters prevention & control, Seasons, Adaptation, Physiological, Climate Change, Crops, Agricultural physiology, Droughts, Ecosystem
- Abstract
Zoning seasonal drought based on the study of drought characteristics can provide theoretical basis for formulating drought mitigation plans and improving disaster reduction technologies in different arid zones under global climate change. Based on the National standard of meteorological drought indices and agricultural drought indices and the 1959-2008 meteorological data from 268 meteorological stations in southern China, this paper analyzed the climatic background and distribution characteristics of seasonal drought in southern China, and made a three-level division of seasonal drought in this region by the methods of combining comprehensive factors and main factors, stepwise screening indices, comprehensive disaster analysis, and clustering analysis. The first-level division was with the annual aridity index and seasonal aridity index as the main indices and with the precipitation during entire year and main crop growing season as the auxiliary indices, dividing the southern China into four primary zones, including semi-arid zone, sub-humid zone, humid zone, and super-humid zone. On this basis, the four primary zones were subdivided into nine second-level zones, including one semi-arid area-temperate-cold semi-arid hilly area in Sichuan-Yunnan Plateau, three sub-humid areas of warm sub-humid area in the north of the Yangtze River, warm-tropical sub-humid area in South China, and temperate-cold sub-humid plateau area in Southwest China, three humid areas of temperate-tropical humid area in the Yangtze River Basin, warm-tropical humid area in South China, and warm humid hilly area in Southwest China, and two super-humid areas of warm-tropical super-humid area in South China and temperate-cold super-humid hilly area in the south of the Yangtze River and Southwest China. According to the frequency and intensity of multiple drought indices, the second-level zones were further divided into 29 third-level zones. The distribution of each seasonal drought zone was illustrated, and the zonal drought characteristics and their impacts on the agricultural production were assessed. Accordingly, the drought prevention measures were proposed.
- Published
- 2013
25. [County-scale N2O emission inventory of China's manure management system].
- Author
-
Wang C, Gao W, Zhou F, Chen Q, Ying N, Xu P, and Hou XK
- Subjects
- Air Pollutants analysis, Animals, China, Environmental Monitoring methods, Refuse Disposal methods, Animals, Domestic, Manure, Nitrous Oxide analysis, Poultry, Waste Disposal Facilities
- Abstract
Manure is one of the two largest contributors to China's N2O emission. By using the county-scale activity data and the regional emission factors and related parameters with spatial differentiation in China in 2008, this paper assessed the N2O emission loading, sources profile, spatial pattern, and uncertainty, aimed to establish a high-resolution N2O emission inventory of China's manure management system in 2008. As compared with the research results based on the IPCC, EDGAR, and other works, the proposed emission inventory was more reliable and comprehensive. The total China' s N2O emission from manure in 2008 was estimated as 572 Gg, among which, the emission from the manure except pasture/range/paddock was 322 Gg (56.3%), from the manure in pasture/range/paddock was 180 Gg (31.5%), and the indirect emission from atmospheric volatilized N deposition and leaching/runoff was 45.8 Gg (8.0%) and 1.23 Gg (0.2%), respectively. The spatial pattern of China's N2O emission from manure was more centralized, and mainly concentrated in Jilin, Shandong, Sichuan, Hunan, Henan, Heilongjiang, and Liaoning provinces, contributing 52.4% of the total emission, and more than 25% being from 84 counties (only < 3% of the whole counties). The proposed emission inventory had a higher spatial resolution and accuracy. Different with this inventory, the IPCC underestimated the direct emission while overestimated the indirect emission, with the regions of higher emission rate being underestimated by -1.5%-6.0% and those of lower emission rate being overestimated by 1.6%-13%. As for the EDGAR, the regions of higher emission rate were underestimated by -18. 8--50.0%, and those of lower emission rate were mostly overestimated by 25%-54.1%.
- Published
- 2013
26. [History and present status of butterfly monitoring in Europe and related development strategies for China].
- Author
-
Fang LJ, Xu HG, and Guan JL
- Subjects
- Animals, Butterflies classification, China, Conservation of Natural Resources, Europe, Population Dynamics, Biodiversity, Butterflies physiology, Climate Change, Ecosystem, Environmental Monitoring methods
- Abstract
Butterfly is an important bio-indicator for biodiversity monitoring and ecological environment assessment. In Europe, the species composition, population dynamics, and distribution pattern of butterfly have been monitored for decades, and many long-term monitoring schemes with international effects have been implemented. These schemes are aimed to assess the regional and national variation trends of butterfly species abundance, and to analyze the relationships of this species abundance with habitat, climate change, and other environmental factors, providing basic data for researching, protecting, and utilizing butterfly resources and predicting environmental changes, and playing important roles in the division of butterfly' s threatened level, the formulation of related protection measures, and the protection and management of ecological environment. This paper reviewed the history and present status of butterfly monitoring in Europe, with the focus on the well-known long-term monitoring programs, e. g. , the UK Butterfly Monitoring Scheme and the Germany and European Union Butterfly Monitoring Scheme. Some specific proposals for conducting butterflies monitoring in China were suggested.
- Published
- 2013
27. [Impacts of human disturbance on the species composition of higher plants in the wetlands around Dianchi Lake, Yunnan Province of Southwest China].
- Author
-
Xiang XX, Wu ZL, Luo K, Ding HB, and Zhang HY
- Subjects
- Biodiversity, China, Lakes, Environmental Restoration and Remediation methods, Human Activities, Plant Development, Plants classification, Wetlands
- Abstract
Introducing higher plants to build semi-natural wetland ecosystem is one of the key approaches to restore the wetlands and lakes that suffered from serious pollution and destruction. Based on the investigation data from 128 quadrats at 26 sampling sites in the wetlands around Dianchi Lake in December 2011-October 2012, and in combining with the references published in the 1960s, this paper discussed the impacts of human activities on the species composition of higher plants in the wetlands around the Lake. In 2012, there were 299 species of 88 families in the wetlands, of which, 181 species were native species, and 118 species were alien ones (including 32 invasive species). Of the 42 species of hydrophytes in the total species, 13 species were alien ones (including 2 invasive species). In comparing with the species data recorded in the 1960s, 232 plants were newly recorded and 43 species disappeared in 2012. Aquatic plants changed obviously. The decreased species were 2 submerged plants, 2 floating plants, and 5 floating leaved plants, and the increased species were 8 emergent plants. Fourteen community types were identified by cluster analysis, of which, the main communities were those dominated by alien species including Pistia stratiotes and Alternanthera philoxeroides. As compared with the data in the 1960s, the plant communities dominated by native species such as Ottelia acuminate and Vallisneria natans were not found presently. Therefore, in the practice of introducing higher plants to restore the degraded wetlands and lakes, it would be necessary to scientifically and appropriately select and blend plant species to avoid the wetland degradation by human activities.
- Published
- 2013
28. [Molecular diversity of arbuscular mycorrhizal fungi in wild and cultured Gynostemma pentaphyllum roots in Xishuangbanna, Southwest China].
- Author
-
Zhou LS and Guo SX
- Subjects
- Biodiversity, China, Polymerase Chain Reaction, Polymorphism, Restriction Fragment Length, Soil Microbiology, Symbiosis, DNA, Fungal analysis, Gynostemma growth & development, Gynostemma microbiology, Mycorrhizae classification, Mycorrhizae genetics, Plant Roots microbiology
- Abstract
By using nested-PCR, DNA cloning, and sequencing techniques, this paper studied the diversity of the community structure of arbuscular mycorrhizal fungi (AMF) in wild and cultured Gynostemma pentaphyllum roots. A total of 551 clones containing 18S rDNA genes of AMF were obtained from the roots. After the analysis of the restriction fragment length polymorphism, 100 different RFLP types were obtained, which were further divided into 20 AMF phylotypes belonging to seven families. The comparison of the sequences of 20 AMF phylotypes with the GenBank database showed that there were 5 AMF phylotypes having high similarity to the sequences of reported AMF species Glomus viscosum, Claroideoglomus etunicatum, Racocetra tropicana, Acaulospora spinosa, and Acaulospora mellea, respectively. These sequences were then assessed for the similarities against the MaarjAM database, and 12 phylotypes showed high similarity to the corresponding molecular virtual taxa, of which, 7 phylotypes were not obtained by the morphological identification of soil asexual spores. Statistical analysis indicated that there were significant differences in the AMF community between wild and cultured G. pentaphyllum roots. The analysis of relative abundance data indicated that Glo-2, Amb-1, and Para-1 were the dominant phylotypes in wild G. pentaphyllum roots, while Glo-3, Glo-8, Glo-10, and Div-1 were the prevalent phylotypes in cultured ones. Claroideoglomeraceae and Ambisporaceae were only detected in wild G. pentaphyllum roots, and Diversisporaceae was only identified in cultured ones.
- Published
- 2013
29. [Spatial heterogeneity in body condition of small yellow croaker in Yellow Sea and East China Sea based on mixed-effects model and quantile regression analysis].
- Author
-
Liu ZL, Yuan XW, Yan LP, Yang LL, and Cheng JH
- Subjects
- Animals, Body Size, China, Oceans and Seas, Regression Analysis, Body Composition physiology, Models, Biological, Perciformes growth & development, Perciformes physiology, Seawater
- Abstract
By using the 2008-2010 investigation data about the body condition of small yellow croaker in the offshore waters of southern Yellow Sea (SYS), open waters of northern East China Sea (NECS), and offshore waters of middle East China Sea (MECS), this paper analyzed the spatial heterogeneity of body length-body mass of juvenile and adult small yellow croakers by the statistical approaches of mean regression model and quantile regression model. The results showed that the residual standard errors from the analysis of covariance (ANCOVA) and the linear mixed-effects model were similar, and those from the simple linear regression were the highest. For the juvenile small yellow croakers, their mean body mass in SYS and NECS estimated by the mixed-effects mean regression model was higher than the overall average mass across the three regions, while the mean body mass in MECS was below the overall average. For the adult small yellow croakers, their mean body mass in NECS was higher than the overall average, while the mean body mass in SYS and MECS was below the overall average. The results from quantile regression indicated the substantial differences in the allometric relationships of juvenile small yellow croakers between SYS, NECS, and MECS, with the estimated mean exponent of the allometric relationship in SYS being 2.85, and the interquartile range being from 2.63 to 2.96, which indicated the heterogeneity of body form. The results from ANCOVA showed that the allometric body length-body mass relationships were significantly different between the 25th and 75th percentile exponent values (F=6.38, df=1737, P<0.01) and the 25th percentile and median exponent values (F=2.35, df=1737, P=0.039). The relationship was marginally different between the median and 75th percentile exponent values (F=2.21, df=1737, P=0.051). The estimated body length-body mass exponent of adult small yellow croakers in SYS was 3.01 (10th and 95th percentiles = 2.77 and 3.1, respectively). The estimated body length-body mass relationships were significantly different from the lower and upper quantiles of the exponent (F=3.31, df=2793, P=0.01) and the median and upper quantiles (F=3.56, df=2793, P<0.01), while no significant difference was observed between the lower and median quantiles (F=0.98, df=2793, P=0.43).
- Published
- 2013
30. [Characteristics of heat resource in mountainous region of northern Guangdong, South China based on three-dimensional climate observation].
- Author
-
Liu W, Wang CL, Chen XG, and Chen HH
- Subjects
- Agriculture, China, Climate Change statistics & numerical data, Sunlight, Climate, Ecosystem, Environmental Monitoring, Hot Temperature
- Abstract
Based on the 2009-2011 daily air temperature observation data from 11 automatic weather stations in the mountainous region of northern Guangdong, this paper calculated the heat factors in the region, including the beginning date of 10 degrees C, the ending date of 15 degrees C, the duration days of 10-15 degrees C, the accumulated temperature above 10 degrees C, the days of minimum temperature below 5 degrees C, and the mean monthly temperature, with the linear regression model of the heat factors and latitude established. In 2009-2011, the heat factors in the region had significant correlations with latitude, and the heat resource at the same latitudes differed apparently between south and north slopes. With the increase of latitude, the beginning date of 10 degrees C delayed, the ending date of 10 degrees C advanced, and the duration days of 10-15 degrees C, the accumulated temperature above 10 degrees C, the days of temperature above 10 degrees C, and the mean annual air temperature decreased. The vertical variation rates of the heat factors were larger on south slope than on north slope. The results of this study could be used for fitting the vertical distribution of heat resource in the areas with no weather station, and provide basis for the fine regionalization of agricultural climate.
- Published
- 2013
31. [Spatiotemporal variation patterns of potential evapotranspiration in five provinces of Northwest China in 1960-2011].
- Author
-
Liu XF, Pan YZ, Zhang JS, and Lin ZH
- Subjects
- China, Climate Change, Spatio-Temporal Analysis, Temperature, Water metabolism, Crops, Agricultural growth & development, Ecosystem, Models, Theoretical, Plant Transpiration, Water Movements
- Abstract
By using Penman-Monteith model and Hurst index model, this paper analyzed the spatiotemporal variation patterns of potential evapotranspiration (ET0) in the five provinces of Northwest China in 1960-2011. In the meantime, the dominant factors driving the variations of the ET0 were quantitatively analyzed by using sensitivity analysis method. In 1960-2011, the ET0 in the five provinces presented an overall decreasing trend, with a drop rate of -0.72 mm x a(-1), but the ET0 increased gradually after 1993. An obvious spatial difference was shown in the annual average ET0. The average ET0 in the five provinces was 1158 mm (675-2282 mm), wit the maximum (2282 mm) in Qijiaojing of Xinjiang and the low values (>800 mm) in Qinba Mountains in south Shaanxi. Except in spring, the ET0 in other seasons showed a decreasing trend. In the analysis of future trend, the ET0 in most areas (81.4%) of Northwest China would present a trend from decrease to increase. Therefore, under the background of global warming, the warm and wet degree in Northwest China would be somewhat weakened, but the ET0 in the middle part of Xinjiang would be decreased continuously. Wind speed was the main factor affecting the ET0 in Northwest China at both annual and monthly scales, but the affecting extent of wind speed differed with seasons and areas. The spatial extent affected by the wind speed in winter expanded across the entire five provinces of Northwest China, while the spatial extent affected by the wind speed in summer included the entire Xinjiang and the northwest of Gansu and Qinghai.
- Published
- 2013
32. [Phthalic acid esters (PAEs) pollution in farmland soils: a review].
- Author
-
Wang KR, Cui MM, and Shi YX
- Subjects
- China, Diethylhexyl Phthalate analysis, Esters analysis, Plasticizers analysis, Crops, Agricultural growth & development, Environmental Monitoring, Phthalic Acids analysis, Soil Pollutants analysis
- Abstract
The environmental pollution and food safety problems caused by phthalic acid esters (PAEs) have been attracted 'extensive attention around the world. As a large PAEs producer and consumer, China is facing severe PAEs environmental pollution problems. This paper reviewed the present pollution status of six PAEs classified by the U.S. Environmental Protection Agency as the priority pollutants in China farmland soils, analyzed the sources of these six PAEs in this country, and discussed the absorption and accumulation characteristics of the PAEs in different crops as well as the bio-toxic effects of PAEs pollutants. The PAEs concentrations in China farmland soils are significantly higher those in the farmland soils of the United States and European countries. The main sources of PAEs in China farmland soils are atmospheric deposition, agricultural films, sewage sludge application, and wastewater irrigation. There exist significant differences in the characteristics of PAEs absorption, accumulation, and distribution among different crops. PAEs not only have negative effects on soil quality, crop growth, and crop physiological and biochemical properties, but also possess bio-accumulative characteristics. The weaknesses in current researches were pointed out, and the suggestions for the further researches were given, e. g., to expand the scope of PAEs pollution survey, to explore the toxic mechanisms of PAEs on crops, and to develop the techniques for in situ remediation of PAEs-polluted soils.
- Published
- 2013
33. [Net ecosystem CO2 exchange and its environmental regulation mechanisms in a reed wetland in the Yellow River Delta of China during the growth season].
- Author
-
Yang LQ, Han GX, Yu JB, Wu LX, Zhu M, Xing QH, Wang GM, and Mao PL
- Subjects
- China, Poaceae growth & development, Rivers, Carbon Dioxide metabolism, Photosynthesis physiology, Poaceae physiology, Wetlands
- Abstract
By using eddy covariance technique, this paper measured the net ecosystem CO2 exchange (NEE) in a reed (Phragmites australis) wetland in the Yellow River Delta of China during the growth season of 2011, and investigated the variation patterns of the NEE and related affecting factors. The average diurnal variation of the NEE in different months showed a U-type curve, with the maximum net CO2 uptake rate and release rate being (0.44 +/- 0.03) and (0.16 +/- 0.01) mg CO2 x m(-2) x s(-1), respectively. The NEE, ecosystem respiration (R(eco)), and gross primary productivity (GPP) were all higher in vigorous growth season (from July to September) and lower in early growth season (from May to June) and late growth season (from October to November). Both R(eco) and NEE reached their maximum values in August, while GPP reached its peak value in July. During the growth season, the ecosystem CO2 exchange was mainly dominated by photosynthetic active radiation (PAR), soil temperature (T(s)), and soil water content (SWC). There was a rectangular hyperbolic relationship between the daytime NEE and PAR. The nighttime ecosystem respiration (R(eco,n)) was exponentially correlated with the T(s) at 5 cm depth, and the temperature sensitivity of the ecosystem respiration (Q10) was 2.30. SWC and T(s) were the main factors affecting the R(eco,n). During the entire growth season, the reed wetland ecosystem in the Yellow River delta was an obvious carbon sink, with the total net carbon sequestration being 780.95 g CO2 x m(-2).
- Published
- 2013
34. [Effects of global climate change on the C, N, and P stoichiometry of terrestrial plants].
- Author
-
Hong JT, Wu JB, and Wang XD
- Subjects
- China, Carbon analysis, Climate Change, Ecosystem, Nitrogen analysis, Phosphorus analysis, Plants chemistry
- Abstract
The response patterns of biogeochemical cycle and the adaptation strategies of terrestrial plants under the background of global climate change have received extensive attention. This paper analyzed the effects of climate warming and precipitation change on the plant C:N:P in different ecosystems, the effects of elevated atmospheric CO2 on the plant nutrients in different photosynthetic pathways, and the short-term and long-term effects of the responses of soil-plant nutrients to nitrogen deposition, and explored the possible underlying mechanisms in terms of the plant physiological properties in relation to soil available nutrients, which could provide theoretical bases for studying the nutrients (C, N and P) transmission and regulation mechanisms between soil and plant, the structure and function of terrestrial ecosystems, and the responses of biogeochemical cycle to global climate change. The existing problems and the further research directions in this study area were proposed.
- Published
- 2013
35. [Characteristics and adaptation of seasonal drought in southern China under the background of global climate change. IV. Spatiotemporal characteristics of drought for maize based on crop water deficit index].
- Author
-
Sui Y, Huang WH, Yang XG, and Li MS
- Subjects
- China, Ecosystem, Seasons, Spatio-Temporal Analysis, Zea mays metabolism, Adaptation, Physiological, Climate Change, Droughts, Water metabolism, Zea mays physiology
- Abstract
Based on the 1959-2008 meteorological data from 249 meteorological stations in southern China, and by using crop water deficit index (CWDI) as the agricultural drought index, this paper calculated the drought frequency and drought stations ratio in this region, and analyzed the spatiotemporal distribution characteristics of drought for spring maize and summer maize during their growth periods. As for the spatial pattern of drought frequency, the drought for spring maize was more severe in the north of Huaihe River, northern Yunnan, and southern South China, but was lighter in the other regions. Except that the drought for summer maize at its late developmental stage was more severe in the middle-lower reaches of Yangtze River, northern South China, and eastern Southwest China, the drought for summer maize at its other developmental stages within southern China was lighter. As for the variation trend of drought intensity and drought area, the drought intensity of spring maize from its seven-leaf stage to jointing stage in the middle-lower reaches of Yangtze River increased obviously, while the drought intensity and drought area of the spring maize from its late spinning stage to milky maturity stage presented a decreasing trend. The drought of summer maize from its late jointing stage to tasseling stage and from late spinning stage to milky maturity stage all showed a decreasing trend. In Southwest China, the drought intensity and drought area for spring maize and summer maize had no clear trend. From the viewpoint of the inter-annual and decadal variability of drought intensity and drought area, there was a larger variation for the summer maize in the middle-lower reaches of Yangtze River, but less difference in Southwest China.
- Published
- 2013
36. [Responses of winter wheat tillers at different positions to low temperature stress at stem elongation stage and their freezing resistance evaluation].
- Author
-
Xu HC, Yin YP, Cai T, Ni YL, Yang WB, Peng DL, Yang DQ, and Wang ZL
- Subjects
- China, Ecosystem, Plant Leaves metabolism, Plant Stems metabolism, Plant Stems physiology, Seasons, Stress, Physiological physiology, Superoxide Dismutase metabolism, Triticum metabolism, Adaptation, Physiological physiology, Agriculture methods, Cold Temperature, Triticum physiology
- Abstract
Taking two winter wheat cultivars Ji' nan 17 and Shannong 8355 as test materials, this paper measured the superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) activities and the malondialdehyde (MDA) and soluble protein contents in the functional leaves and sheaths of the tillers at different positions at stem elongation stage under low temperature stress, and then, the freezing resistance of the tillers was comprehensively evaluated by the methods of principal component analysis and cluster analysis. The results showed that under low temperature stress, the SOD, POD, and CAT activities in the functional leaves and sheaths of each tiller at stem elongation stage increased, but the MDA and soluble protein contents increased or decreased to some extent. By using principal component analysis and cluster analysis, the tillers of each cultivar were grouped into three kinds of freezing resistance type. For Ji' nan 17, the main stem, tiller I, and tiller II belonged to high freezing resistance type, the tiller III, tiller IV, and tiller I p belonged to medium freezing resistance type, and the tiller II p belonged to low freezing resistance type. For Shannong 8355, the main stem, tiller I, tiller II, and tiller III belonged to high freezing resistance type, the tiller IV and tiller I p belonged to medium freezing resistance type, and the tiller II p belonged to low freezing resistance type. It was concluded that the freezing resistance of the winter wheat tillers at different positions at stem elongation stage differed, with the lower position tillers being more resistant than the higher position tillers.
- Published
- 2013
37. [Effects of actinomycetes agent on ginseng growth and rhizosphere soil microflora].
- Author
-
Zhang HY, Xue QH, Shen GH, and Wang DS
- Subjects
- Actinobacteria growth & development, Biomass, China, Ginsenosides analysis, Plant Roots growth & development, Pseudomonas growth & development, Pseudomonas fluorescens growth & development, Quality Control, Rhizosphere, Microbiota, Panax growth & development, Soil Microbiology, Streptomyces physiology
- Abstract
Taking the ginseng in Xiao Xing' an Mountains of Northeast China as test object, this paper studied the effects of applying Streptomyces pactum (Act12) on ginseng growth and on the soil microflora in root zone and root surface. After treated with Act12, the yield and quality of ginseng' s medicinal part improved, the induced enzyme activities in leaves and the root activity increased, and the numbers and proportions of soil bacteria and actinomycetes increased significantly while those of soil fungi decreased. Compared with the control, the soil microflora in treatment Act12 changed. The numbers of the dominant bacteria Pseudomonas fluorescens, Pseudomonas koreensis, and Microbacterium oxydans were much higher in root zone soil and root surface soil, and the pathogen Plectosphaerella cucumerina decreased in root zone soil and disappeared in root surface soil. These results suggested that the addition of Act12 could improve the soil microflora, enhance the resistance and root activity of ginseng plant, and increase the ginseng yield and its quality.
- Published
- 2013
38. [Population structure and spatial distribution pattern of Camellia azalea in E' huangzhang Nature Reserve of Guangdong, China].
- Author
-
Li XL, Sun ZY, Li JY, Xu Y, and Luo J
- Subjects
- Camellia classification, China, Population Dynamics, Spatial Analysis, Camellia growth & development, Conservation of Natural Resources
- Abstract
This paper studied the structures of basal diameter, height and canopy width of Camellia azalea population in E' huangzhang Nature Reserve of Guangdong. The spatial distribution patterns and dynamics of the population were measured by applying aggregate indices including disperse coefficient, negative binomial distribution, Cassie index, clumping index, mean crowding, patch index and Green index. The results showed that in the natural distribution region, the population was mainly composed of adult trees, and was in declining due to seriously lack of seedlings. The structures of diameter, height and canopy width were not identical among different plots. In the plots, the spatial distribution pattern of C. azalea population showed clump or random, and changed from clump to random with the development of the population.
- Published
- 2013
39. [Characteristics of soil microbial community under different vegetation types in Wuyishan National Nature Reserve, East China].
- Author
-
Wu ZY, Lin WX, Chen ZF, Fang CX, Zhang ZX, Wu LK, Zhou MM, and Shen LH
- Subjects
- Biodiversity, China, Conservation of Natural Resources, Microbial Consortia, Trees growth & development, Forests, Soil Microbiology, Trees classification
- Abstract
By using Biolog Ecoplate system, this paper studied the structure and functional diversity of soil microbial community under different vegetation types in Wuyishan National Nature Reserve, aimed to probe into the effects of vegetation type on the diversity of soil microbial community. The results showed that the soil chemical properties, soil enzyme activities, and average well color development (AWCD) were higher in natural forest than in planted forest, and were the lowest in abandoned field. The AWCD reflecting soil microbial activity and functional diversity was increased with increasing incubation time, but there existed significant differences among different vegetation types. The carbon sources mostly used by soil microbes were carbohydrates and carboxylic acids, followed by amino acids, phenolic acids and polymers, and amines had the lowest utilization rate. The Simpson index, Shannon index, Richness index and McIntosh index in natural forest were holistically higher than those in planted forest. Principal component analysis (PCA) identified 2 principal component factors in relation to carbon sources, explaining 56.3% and 30.2% of the variation, respectively. The carbon sources used by soil microbial community differed with vegetation types. Amino acids and amides were the two main carbon sources separating the 2 principal component factors. The results of this study could provide basis for further approaching the relationships between vegetation diversity and soil microbial community diversity.
- Published
- 2013
40. [Suitability assessment of construction land in the central and southern parts of Hebei Province, China based on potential-limitation model].
- Author
-
Yin HW, Kong FH, Luo ZD, Yan WJ, Sun CF, and Xu F
- Subjects
- China, Environmental Monitoring methods, City Planning, Conservation of Natural Resources methods, Ecosystem, Models, Theoretical, Urbanization
- Abstract
The suitability assessment of regional construction land is one of the important prerequisites for the spatial arrangement in regional planning, and also, the important foundation for the reasonable utilization of regional land resources. With the support of GIS, and by using the regional comprehensive strength and spatial accessibility analysis and the eco-environmental sensitivity analysis, this paper quantitatively analyzed the development potential and its ecological limitation of the central and southern parts of Hebei Province. Besides, based on the cost-benefit analysis, the potential-limitation model was accordingly developed, and the three land suitability scenarios under different developmental concepts were captured through the interaction matrix. The results indicated that both the comprehensive strength and the development potential of the study area showed a primacy distribution pattern, and presented an obvious pole-axis spatial pattern. The areas with higher eco-environmental sensitivity were mainly distributed in the west regions, while those with lower eco-environmental sensitivity were in the east regions. Regional economic development concept had important effects on the regional ecological security pattern and urban growth. The newly developed principles and methods for the land suitability assessment in this paper could not only scientifically realize the spatial grid of regional development potential and capture the future land development trend and spatial distribution, but also provide scientific basis and effective ways for urban and regional planning to realize region 'smart growth' and 'smart conservation'.
- Published
- 2013
41. [Estimation of shelter forest area in Three-North Shelter Forest Program region based on multi-sensor remote sensing data].
- Author
-
Zheng X and Zhu JJ
- Subjects
- China, Conservation of Natural Resources statistics & numerical data, Forestry methods, Forests, Remote Sensing Technology methods, Trees growth & development
- Abstract
The Three-North Shelter Forest Program is a key forestry ecological project in China. The quantity and spatial distribution of the shelter forest in the program affect the ecological environment of the entire Three-North region. In this paper, multi-sensor remote sensing data were used to scientifically, objectively and comprehensively estimate the quantity and spatial distribution pattern of the shelter forest in this region in 1978-2008. Firstly, the Landsat TM images (30 m in resolution) were adopted to extract the shelter forest data in this region in 2008. Then, based on random sampling techniques, the calibration formulae for the shelter forest area in different precipitation climate regions estimated by the SPOT5 (2.5 m in resolution) and Landsat TM were constructed. By using the above-mentioned results, the shelter forest area in the Three-North region in 2008 was estimated. In 2008, the total area of the shelter forest (canopy density of arbor shelter forest was >0.3, coverage of shrub shelter forest was > 40%, and accuracy was about 85%) in this region was 328360.03 km2, with 116244.55 km2 in Northeast China, 42981.32 km2 in North China, 76767.05 km2 in Loess Plateau, and 92367.11 km2 in Mongolia-Xinjiang Region. According to the classification of shelter forest types, the areas of coniferous forest, broadleaved forest, mixed broadleaf-conifer forest and shrubland were 62614.74, 121628.51, 22144.09 and 121972.69 km2, respectively.
- Published
- 2013
42. [Effects of forest ownership regime on landscape pattern and animal habitat: a review].
- Author
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Li YH, Wu W, Li NN, Bu RC, and Hu YM
- Subjects
- Animals, China, Trees growth & development, Conservation of Natural Resources, Forestry organization & administration, Forests, Ownership
- Abstract
In some European and North American countries where forestry is highly developed, both public and private forest ownership regimes have being existed for a long time. Currently, the researches about both the dynamics of forest landscape and habitat pattern and the relationship between habitat pattern and biological conservation in multi-ownership forest landscape are increasingly becoming important. This paper reviewed the effects of multi-ownership regime on forest landscape pattern and animal habitat and emphasized on the ecological consequences of forest parcelization and land divestiture, including the provision of diverse habitats and fragmentation of the existing large-area habitat. This paper also summarized two ways (changing the ownership pattern and integrating the multi-ownership management by cross boundary coordination) for handling the conflicts between small-scaled multi-ownership management and biological conservation at large scale in forestry-developed countries and analyzed the reasons that those countries prefer to adopt the latter one. Furthermore, the methodological limitations in simulating ownership pattern were pointed out. Finally, the present status, challenges and opportunities in the above-mentioned research issues in China were discussed, and the suggestions for further researches were provided.
- Published
- 2013
43. [Cleistogenes squarrosa population at different restorative succession stages in Inner Mongolia of China: a point pattern analysis].
- Author
-
Wang XT, Wang W, Liang CZ, and Bao JJ
- Subjects
- China, Cluster Analysis, Photography, Population Dynamics, Ecosystem, Environmental Restoration and Remediation, Poaceae classification, Poaceae growth & development
- Abstract
In this paper, the spatial pattern of Cleistogenes squarrosa population in different restorative succession communities of the typical steppe dominated by Stipa grandis and Leymus chinensis in Inner Mongolia was measured by photography orientation, and analyzed by complete spatial randomness model, Poisson cluster process, and nested double-cluster process. In severely degraded community, C. squarrosa population fitted well nested double-cluster process for all scales, i. e., high density small clusters existed at the centers of large clusters; whereas in 5-, 8-, and 21-year-old restored communities, C. squarrosa population fitted well Poisson cluster process for all scales, i. e. , high density small clusters did not exist at the centers of the clusters. It was suggested that facilitation was the dominant interaction in severely degraded community, while competition dominated in restored communities. The differences in the spatial pattern of C. squarrosa population during the restorative succession could be induced by the shift from facilitation to competition along the gradient of grazing stress.
- Published
- 2013
44. [Effects of light on submerged macrophytes in eutrophic water: research progress].
- Author
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Li-Sha Z, Ze-Yu N, Xiao-Yan Y, and Ji-Yan S
- Subjects
- China, Hydrobiology methods, Water Pollutants, Chemical analysis, Water Pollution analysis, Ecosystem, Eutrophication radiation effects, Phytoplankton radiation effects, Sunlight, Water Pollution prevention & control
- Abstract
The restoration of submerged macrophytes is the key to remediate eutrophic water and maintain the health of aquatic ecosystem, while light is the main limiting factor. This paper summarized the factors affecting the light extinction in water and the mechanisms of light intensity affecting the physiology of submerged macrophytes, with the focuses on the metabolic mechanisms of carbon, nitrogen, and phosphorus, the responses of antioxidant enzyme system, and the feedbacks of pigment composition and concentration in the common submerged macrophytes under low light stress. Several engineering techniques applied in the ecological restoration of submerged macrophytes were presented, and the framework of the restoration of submerged macrophytes in eutrophic water was proposed. Some problems in current research and several suggestions on future research were addressed, which could help the related research and engineering practices.
- Published
- 2013
45. [Spatiotemporal patterns and driving forces of land use change in industrial relocation area: a case study of old industrial area in Tiexi of Shenyang, Northeast China].
- Author
-
Wang ML, Bing LF, Xi FM, Wu R, and Geng Y
- Subjects
- China, Geographic Information Systems, Industry, Mining, Remote Sensing Technology, Spatio-Temporal Analysis, City Planning, Conservation of Natural Resources methods, Ecosystem, Environment Design
- Abstract
Based on the QuickBird remote sensing images and with the support of GIS, this paper analyzed the spatiotemporal characteristics of land use change and its driving forces in old industrial area of Tiexi, Shenyang City of Liaoning Province in 2000-2010. During the study period, the industrial and mining warehouse land pattern had the greatest change, evolving from the historical pattern of residential land in the south and of industrial land in the north into residential land as the dominant land use pattern. In the last decade, the residential land area increased by 9%, mainly transferred from the industrial and mining warehouse land located in the north of Jianshe Road, while the industrial and mining warehouse land area decreased by 20%. The land areas for the commercial service and for the administrative and public services were increased by 1.3% and 3.1%, respectively. The land area for construction had a greater change, with an overall change rate being 76.9%. The land use change rate in 2000-2005 was greater than that in 2005-2010. National development strategies and policies, regional development planning, administrative reform, and industrial upgrading were the main driving forces of the land use change in old industrial area of Tiexi.
- Published
- 2013
46. [Fish community structure and its relationships with environmental factors in Haizhou Bay and adjacent waters of East China in winter].
- Author
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Wang XL, Xu BD, Ji YP, and Ren YP
- Subjects
- Animals, China, Fishes growth & development, Oceans and Seas, Population Dynamics, Seasons, Bays, Environment, Fishes classification
- Abstract
Based on the bottom trawl survey and environmental investigation data in December 2011, and by using species diversity indices and multi-element analysis, this paper studied the species composition, species diversity, and spatial pattern of fish community as well as their relationships with environmental factors in Haizhou Bay and adjacent waters. A total of 60 fish species were captured, belonging to 51 genera, 34 families, and 10 orders, and mainly composed of warm temperature and warm water demersal fishes. The Margalef species richness index, Shannon diversity index, and Pielou evenness index ranged from 1.14 to 2.84, 1.08 to 2.64, and 0.41 to 0.83, respectively. Cluster analysis and non-metric multidimensional scaling (MDS) analysis showed that the fish community could be spatially clustered into three groups. Group I was in the north of 35 N, group II was in the inshore waters near bay-head, and group III was in the south of 35 degrees N. ANOSIM analysis showed that there existed highly significant differences (R = 0.45-0.91) in the fish species composition among the groups. The canonical correspondence analysis (CCA) indicated that the bottom water temperature, water depth, and sea surface salinity were the most important environmental variables affecting the spatial pattern of fish community in Haizhou Bay and adjacent waters in winter.
- Published
- 2013
47. [Relationships of wetland landscape fragmentation with climate change in middle reaches of Heihe River, China].
- Author
-
Jiang PH, Zhao RF, Zhao HL, Lu LP, and Xie ZL
- Subjects
- China, Computer Simulation, Geographic Information Systems, Models, Theoretical, Remote Sensing Technology, Rivers, Climate Change, Wetlands
- Abstract
Based on the 1975-2010 multi-temporal remotely sensed TM and ETM images and meteorological data, in combining with wavelet analysis, trend surface simulation, and interpolation method, this paper analyzed the meteorological elements' spatial distribution and change characteristics in the middle reaches of Heihe River, and elucidated the process of wetland landscape fragmentation in the study area by using the landscape indices patch density (PD), mean patch size (MPS), and patch shape fragment index (FS). The relationships between the wetland landscape fragmentation and climate change were also approached through correlation analysis and multiple stepwise regression analysis. In 1975-2010, the overall distribution patterns of precipitation and temperature in the study area were low precipitation in high temperature regions and high precipitation in low temperature regions, and the main characteristics of climate change were the conversion from dry to wet and from cold to warm. In the whole study period, the wetland landscape fragmentation was mainly manifested in the decrease of MPS, with a decrement of 48.95 hm2, and the increase of PD, with an increment of 0.006 ind x hm(-2).
- Published
- 2013
48. [Prediction models for ground surface fuels moisture content of Larix gmelinii stand in Daxing'anling of China based on one-hour time step].
- Author
-
Yu HZ, Sen J, and Di XY
- Subjects
- China, Forecasting, Humidity, Plant Leaves, Fires, Larix growth & development, Models, Theoretical, Water analysis
- Abstract
By using the equilibrium moisture content-time lag methods of Nelson and Simard and the meteorological element regression method, this paper studied the dynamics of the moisture content of ground surface fine dead fuels under a Larix gmelinii stand on the sunny slope in Daxing' anling with a time interval of one hour, established the corresponding prediction models, and analyzed the prediction errors under different understory densities. The results showed that the prediction methods of the fuels moisture content based on one-hour time step were applicable for the typical Larix gmelinii stand in Daxing' anling. The mean absolute error and the mean relative error of Simard method was 1.1% and 8.5%, respectively, being lower than those of Nelson method and meteorological element regression method, and close to those of similar studies. On the same slopes and slope positions, the fuel moisture content varied with different understory densities, and thus, it would be necessary to select the appropriate equilibrium moisture content model for specific regional stand and position, or establish the fuel moisture content model based on specific stand when the dynamics of fuel moisture content would be investigated with a time interval of one hour.
- Published
- 2013
49. [Effects of thinning on fine-root morphology, biomass and N concentration of different branch orders of Chinese fir].
- Author
-
Wang ZH, Li RX, and Guan QW
- Subjects
- China, Cunninghamia metabolism, Ecosystem, Plant Roots anatomy & histology, Plant Roots metabolism, Biomass, Cunninghamia growth & development, Forestry methods, Nitrogen metabolism, Plant Roots growth & development
- Abstract
Taking a 25-year old Chinese fir (Cunninghamia lanceolata) plantation as the object, this paper studied the effects of thinning on the biomass, morphological traits, and nitrogen concentration of the first five orders roots. With the increase of root order (from the first to the fifth order), there was a significant increase in the fine-root biomass, diameter, and tissue density, and a significantly decrease in the specific root length (SRL), root length density (RLD), and root number (RN). Thinning increased the biomass, RLD, and RN of the first and second orders roots as well as the tissue density of the first, third, fourth, and fifth orders roots significantly, but had no effects on the SRL and nitrogen concentration of each order root. In contrast, thinning decreased the diameter of the first, third, and fourth orders roots significantly. The diameter of the second order roots was obviously smaller in surface (0-10 cm) soil than in subsurface (10-20 cm) soil, while the RLD of the first three orders roots and the RN and nitrogen concentration of the first two orders roots were larger in surface soil than in subsurface soil. The interaction of thinning and soil layer only decreased the diameter of the first two orders roots. It was suggested that the fine-root biomass and morphological traits of Chinese fir were closely related to the vegetation growth and regeneration after thinning.
- Published
- 2013
50. [Ecosystem services supply and consumption and their relationships with human well-being].
- Author
-
Wang DS, Zheng H, and Ouyang ZY
- Subjects
- China, Conservation of Natural Resources methods, Humans, Conservation of Natural Resources economics, Ecosystem, Environmental Monitoring methods
- Abstract
Sustainable ecosystem services supply is the basis of regional sustainable development, and human beings can satisfy and improve their well-being through ecosystem services consumption. To understand the relationships between ecosystem services supply and consumption and human well-being is of vital importance for coordinating the relationships between the conservation of ecosystem services and the improvement of human well-being. This paper summarized the diversity, complexity, and regionality of ecosystem services supply, the diversity and indispensability of ecosystem services consumption, and the multi-dimension, regionality, and various evaluation indices of human well-being, analyzed the uncertainty and multi-scale correlations between ecosystem services supply and consumption, and elaborated the feedback and asynchronous relationships between ecosystem services and human well-being. Some further research directions for the relationships between ecosystem services supply and consumption and human well-being were recommended.
- Published
- 2013
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