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2004 Vol.2 No.4
Published 2004-12-31
Articles
1
LIU Shen-；Guo-Suo-Pan-；Zhang-Wen-Cong-；Shi-Li-Ren-；Jie-Meng-Shu-；Chen-Fa-Yang
Integrated Management: The Certainty Choice of Flood Hazard Control and Ecological Rehabilitation in Qin-Ba Mountainous Region
In order to prevent and reduce natural calamities, improve people's living environment in Qin-Ba mountainous area in the south of Shaanxi, general situation and flood disasters in this area are introduced and the causes of disaster are analyzed. The reasons causing river bank destroyed by flood is not only natural factors but also human factors, including altering river beach for farmland, contracting river section, not leaving outlets for flood, soil and water conservation deficiency in the upper reaches and river scouring lagging, and so on. Countermeasures for preventing and reducing disasters and improving environment are that dealing with the relation between human and nature properly, changing contesting land with flood into leaving outlets for flood, making overall plans, reinforcing soil erosion comprehensive control in the upper reaches and enhancing soil and water conservation preventing supervision and river scouring.
2004 Vol. 2 (4): 1-5 [
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1351
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1369
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6
LIU Yong-Mei-；Li-Dui-；Yang-Qi-Ke
Remote Sensing Classification of Land Use Based on Image Fusion in the Loess Hilly Region of Northern Shaanxi Province
The land use classification accuracy is unsatisfactory based on single remotely sensed data and supervised classification in the land use investigation of loess hill and gully area. Taking the watershed of WuDing River of Northern Shaanxi Province as a test area, the TM multi-spectral data and SPOT pan data are merged by the method of Principal Components Analysis. Then, based on the merged image, the land use categories are extracted by applying an integration of supervised classification and unsupervised classification, which improved sampling method remarkably. The total accuracy increased from 82.0% to 89.2%, especially the accuracy of city and town area, paddy field, water area increased over 10%, the mixture of sloping field and forest (grassland) decreased remarkably and the accuracy of the two categories increased over 5% respectively by the combination of two methods, compared to the classification based on the single TM multi-spectral data and supervised classification. The result is of critical significance in land use dynamic monitoring in the area.
2004 Vol. 2 (4): 6-10 [
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1441
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11
YANG Xiao-Hui-；Tun-Bei
Preliminary Assessment of Forest Function on Soil and Water Conservation in Eastern Regions of Daxinganling Mountains
Forest function on soil and water conservation has drawn more attention from the Chinese publics. It is estimated that the soil erosion amount before and after cutting in the eastern forest area of Daxinganling Mountains using GIS and USLE, the results showed that annual soil erosion amount before cutting was 485万8658.55t, and that after cutting was 1亿4109万9989.4t which was equal to 29 times of that before cutting. Soil erosion modulus in all the forestry bureaus before cutting is lower than tolerant soil loss amount (200t/(km
2
·a)) in this region, while that after cutting was higher than tolerant soil loss amount; the maximum value was 3849.57t/(km
2
·a) in Huzhong Forestry Bureau where soil erosion was very severe. It is obvious that forest function on soil and water conservation in this region is very great. In the whole region, spatial pattern of soil erosion modulus before cutting coincides with that after cutting with decreasing trend from west to east, which is similar to the change of slope factor in this region, it can be concluded that vegetation coverage is main influencing factor for soil erosion, while slope gradient is main factor influencing spatial difference of soil erosion. Undoubtedly, this research will be helpful to formulate subsidy mechanism for ecological benefit and to determine priority of protection for ecological units in this region.
2004 Vol. 2 (4): 11-16 [
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1427
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17
CHENG Gen-Wei-；Dan-Pei-Li
Benefits of Forest Water Conservation and Its Economical Value Evaluation in Upper Reaches of Yangtse River
In order to enrich value quantitative study of forest ecological system function, impersonally appraise eco-conservation benefits in west-south area of China, based on difference of natural geographical environmental condition, the upper reaches of Yangtse River is divided into 6 physical geographical zones, including dark-coniferous forest, conifer-broad mixed forest, broad forest, cash forest, bamboo forest, bush lands. The capacity of forest water conservation is calculated according to precipitation and runoff characteristic parameters in the area. The principle of “Alternating Engineering and Shade price” is applied to estimate the economic value of water conservation caused by forest ecological system. The results show that the annual water conservation storage caused by forest ecological system in upper reaches of Yangtse River is 1288×10
8
m
3
, which mainly concentrated in high mountainous gorge area, and its economic values is 432×10
8
Yuan.
2004 Vol. 2 (4): 17-20 [
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1312
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1396
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21
ZHANG Jin-Che-；Huang-Jia-Yin-；Lu-Xiao-Zhen
Stem Sap Flow of Poplar of Shelter-belt on Farmland in Xu-Huai Plain
In order to open out the threaten field mechanism of shelter-belt on farmland to nearby crop, and offer theoretical base to tree allocation of shelter-belt on farmland and establishment countermeasures to threaten field, the stem sap flow of 8 years' NL80105 Poplar and 11 years' I69 Poplar in growing season were measured by means of ICT2000TE based on thermal pulse technique. The results show that the intensity of sap flow of I69 Poplar was 0.244L·cm
-2
·d
-1
, and that of NL80105 Poplar was 0.172L·cm
-2
·d
-1
. Neglecting the store of moisture tree crown position, it was taken a conclusion that the transpiration intensity of I69 Poplar was relatively higher than that of NL80105 Poplar; the diurnal change of sap flow showed a tendency of low-high-low; at night the sap flow could be obvious increase in I69 Poplar and NL80105 Poplar.
2004 Vol. 2 (4): 21-25 [
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1309
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26
GAO Zhong-Qi-；Zhang-Hong-Jiang-；Shi-Yu-Hu
Amount of Soil Loss Under Different Land Use Type in Granite Area of Three Gorges of Yangtze River
Research on the sediment sources in small watershed of Three Gorges Reservoir Area can guarantee hydro-junction engineering's safe working and benefit exertion. In the selected typical small watershed, several soil profiles were dug, and the relationship between physical characteristics of soil under different types of land utilization and soil erosion is analyzed through the investigation of soil erosion, the observation of sediment and runoff in slope plot. The quantity of soil erosion in different slopes and gully under different types of land utilization is measured. The results show that the characteristics of soil grain under different types of land utilization are closely correlated to the extent of soil loss. With the increasing of soil loss, the sorting coefficient for soil particle diameter of A layer decrease in different types of land utilization. The symmetry of diameter groups is low in different types of land utilization. Sediment in granite area of Three-Gorges mainly originates from soil erosion in slope. Sediment yielded from slope chiefly comes from arable land located at slope, and the quantity of sediment yielded from arable land located at the slope above 25°accounts for about 50% of the total sediment yielded from slope.
2004 Vol. 2 (4): 26-29 [
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1714
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1114
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30
ZHANG Xiao-Ping-；Li-Dui-；Yang-Qi-Ke
Evaluation of Land Use Suitability at the Vulnerable Ecological Area Based on RS/GIS
Land use planning is crucial to the areas that are under severing soil erosion. Land evaluation is an important basis for landscape and land use planning. A framework was developed for land evaluation in Liudaogou watershed with typical characteristics of water-wind erosion crisscross region, in the loess plateau, focusing on integrative, process and ecological analysis. Landuse data in 1990 and 2002 were collected from RS data and GIS was used for data storage and analysis. The landuse rational index from the point of land slope degree for two periods was calculated and four limiting factors (the section of landform, slope degree, soil type and soil erosion intensity) were selected and their ranking and weighted contribution were given to evaluate the suitability of current land source for farmland, grassland and forest separately in 2002. By comparing the different suitability of current farmland, grassland and woodland, measures for better land use and conservation are suggested.
2004 Vol. 2 (4): 30-36 [
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1493
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3407KB] (
1207
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37
WANG Ke-Qi-；Guo-Feng-Chun-；He-Ting-Rong-；Wang-Jian-Wen-；Li-Jin-Hong
The Community Structure of Artificial
Eucalyptus Camaldulensis
Stands in the Dry-Hot Valley of Jinsha River
Through analyse on indexes in common use of community stability describing such as community structure, plant species diversity, growth yield and biomass yield, the density of artificial
Eucalyptus camaldulensis
forests are high widely, the structure is simple and the community stability is lower in dry-hot valley of Jinsha River. With increasing of stands density of three
Eucalyptus camaldulensis
form,the vegetation communities difference under forest canopy increased, there was mainly dominant species in forest (arbor species is
Eucalyptus camaldulensis
, the species under forest canopy is Cheteropogon contortus), the few other species was exist in forest, the vegetation layer structure under forest canopy was simple. With increasing of stands density, the species enrichment (
S
), Shannon-Wiener index (
SW
), species equality (
E
) and ecological dominance (
ED
) minished, the species diversity of community decreased, the community structure changed to badness. The growth yield and biomass yield of community reduced with increasing of stands density also. The biomass yield of the lowest density forest (F
1
) was more than the double of that one of the other higher density forest. The tree growth of all forests was slowness. The average annual growth quantity of diameter and height was 0.72cm and 0.78m respectively even in the lowest density forest (F
1
). To improve the stability of artificial arbor community and advance their positive succession in Jinsha River dry-hot valley, bring into play their ecological function, it is should be considered to reduce the arbor layer community density of artificial forest.
2004 Vol. 2 (4): 37-41 [
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1515
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1263
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42
WU Jian-Wei-；Lu-Rui-Ji-；Diao-Ting-Ning
Study on Climatic and Environmental Changes of the Past 500 Years From Lacustrine Sediment in Otindag Sandy Land
Based on analysis of grain size, geochemical elements, organic matter and CaCO
3
records in lacustrine sediment in Baiyin-kulun lake, combined with 210Pb and 137Cs, the sequence of climatic and environmental change of Otindag Sandy Land was reconstructed in the past 500 years, including two important climate events, i. e. the Little Ice Age and the Global Warming at the beginning of 20th century. The results showed that from A.D.1500 to A.D.1600, the climate was arid and cold, the development of vegetation was restrained. From A.D.1600 to A.D.1760, the climate was warm and wet or warm and arid, the water level of lake was rising and the coverage rate of vegetation increased. From A.D.1760 to A.D.1900, the climate was relatively warm and wet at the first stage, and the climate was cold and arid at the last stage. The Little Ice Age was over at about A.D.1900, temperature and precipitation increased. However, the climate was gradually warm and drought in late and modern day.
2004 Vol. 2 (4): 42-47 [
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1493
) [
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2878KB] (
1367
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48
CHEN Guo-Jian-；Li-Dui-；Yang-Qi-Ke-；Wang-Gang
Influence of Removal Lands From Cultivation to Afforestation and Grass Planting on Rural Social Economy in Loess Hilly-Gully Region in North Shaanxi: A Case Study on Xiannangou Watershed and Yangou Watershed
Based on theoretical base of Rapid Rural Assessment (RRA), the social economic changes of Xiannangou and Yangou watersheds were analyzed. The project of removal lands from cultivation to afforestation and grass planting has been carried out since 1999 in two watersheds. The results showed that the project could lead the output of food and income to reduce, however, which also could accelerate adjustment of agricultural industrial structure and multivariate development of family income. At last, the countermeasures aiming at negative influence of the project were put forward.
2004 Vol. 2 (4): 48-52 [
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1400
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2813KB] (
1140
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53
DUAN Wen-Biao-；Chen-Li-Xin-；Tu-Xin-Xiao
Evaluation and Analysis of Sustainable Development of Puwa Small Watershed Comprehensive Management in Beijing Mountainous Area
Applicable, operative and simplified indicator system frame for sustainable development of Puwa small watershed comprehensive management was brought forward. This indicator system was composed of goal layer, category indicator layer, item indicator layer, and indicator variable layer, totally including 16 concrete indices. Small watershed sustainable development degree was used to describe the sustainable development ability and level of its comprehensive management. It was composed of social development capacity, economic development capacity, and resource and environment carrying capacity. Social development capacity was composed of material demand degree and core development degree. Economic development capacity was reflected by economic wealthy degree. Resource and environment carrying capacity was composed of resource richness degree and environment endurance degree. According to the sequence from indicator variable layer, item indicator layer, category indicator layer to goal layer, every indicator value in every layer was calculated out, the indicator value of sustainable development degree of small watershed comprehensive management was eventually computed by using the data from Puwa typical small watersheds under the direction of sustainable development theory. Puwa small watershed sustainable development in different years was scientifically evaluated and analyzed.
2004 Vol. 2 (4): 53-57 [
Abstract
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1779
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2990KB] (
1260
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58
XIONG Wen-Lan-；Chen-Yi-Bing-；Lin-Chao-Wen
The Pollution Evaluation of Pesticide Infiltration to Groundwater by PEARL Model
By PEARL (Pesticide Emission Assessment of Regional and Local Area) model, the movement condition of pesticide in the soil-plant system was simulated, and pesticide in different concentration standard which is safe or dangerous to groundwater was estimated. At last, aiming at utilization condition of pesticide in China, the suggestion on pesticide polluting ground water research and limiting indexes of pesticide in ground water were put forward.
2004 Vol. 2 (4): 58-65 [
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1440
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3793KB] (
1175
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66
ZHANG Ke-Bin-；Li-Rui-；Hou-Rui-Ping-；Jiao-Feng-；Yang-Dun-Jie
Study on Plant Diversity of Different Control Measures of Desertification in Yanchi County,Ningxia
The changes of the plant diversity under the different desertification controlling measures will contribute to make countermeasures and measures of desertification combating and controlling. The plant diversity of grassland community under the different desertification controlling measures (by converting cropland to forests, artificial fencing and discontinuing farming and letting go out of cultivation) in Yanchi County, Ningxia Hui Autonomous Region was measured by using the methods of
α
-diversity index (including Shannon-Wiener index, Simpson index,
J
sw
and
J
s
which are community evenness indces) and
β
-diversity index (measured by similarity coefficients). Compared with the different fixed sample plot observation data in 2002 and 2003, the results show that
α
-diversity of studied plots increased in varying degree in 2003. By means of comparing beta index, the results also show that the species composition of experimented plots have changed to various extent. In addition, the main causes why the plant diversity in Yanchi County became better than ever is also presented.
2004 Vol. 2 (4): 66-72 [
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1466
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1421
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73
DIAO Ting-Ning-；Cao-Zi-Long-；Zheng-Cui-Ling-；Sun-Bao-Beng-；Ding-Guo-Dong
Impacts of High-parallel Sand-barrier on Soil Organic Matter Contents and Particle Composition of Serious Desertified Grassland
In order to find some new ways for vegetation rehabilitation of desertified grassland,and provide theoretical support for taking effective measures to prevent grassland from degradation,based on the investigation of the soil organic matter contents and soil prarticle composition in different parts of sand dunes,(windward slope,leeward slope and lowland between sand dunes) and in the different locations of sand-barrier (the windward side parts,leeward side and the intersection of sand-barrier),where the grassland was in serious desertification and installed with high-parallel reed sand-barrier of different ages (2～3 and 4～5 years),it was studied that the high-parallel sand-barrier's benefits on controlling grassland after serious desertification by comparing with the same kind of places without sand-barrier. The results showed that contents of soil organic matter could be increased obviously by installation of high-parallel sand-barrier in grassland after serious desertification. In the terms of particle composition,coarse sand was decreased and fine sand was increased.
2004 Vol. 2 (4): 73-77 [
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1659
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78
BANG Biao
Directional Silviculture Experiment and Benefits of Natural Secondary Broad-leaf ForestQ
Evergreen broad-leaf forest was the zonal vegetation of Fujian province, however, in the development of edible fungus industry, plenty of it were destroyed for deficient forest. Probing into the technology of altering deficient forest of natural secondary broad-leaf forest to professional forest of edible fungus, which was important to settle contradiction between fungus and secondary broad-leaf forest and problem of soil erosion. Based on experiment of artificial measures promoting regeneration and improvement of directional silviculture of professional forest of edible fungus, results showed that for the alteration of secondary broad-leaf forest, its investment was sparing, forest maturity was ahead of schedule, period of growth was short, and economic benefits were considerable. Volume amount of the eighth year reached 92 1m
3
/hm 2, 78 3t/hm
2
of edible fungus material could be offered, and the rate of devotion to yield was 1∶13 9. The measures of artificial alteration ad favorable eco-benefits of soil and water conservation and function of enhancing soil fertility etc., and which had not harmful effects to species constitute of community. So the measures of closing hillside for erosion control, selecting excellent seedling of objective trees, clearing weed, cirrus and non-objective forest away, cutting too high stump down, selecting vigorous branches and replanting at space in forest were effective to directional silviculture natural deficient broad-leaf forest to professional forest of edible fungus.
2004 Vol. 2 (4): 78-81 [
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1385
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82
CHA Tong-Gang-；Sun-Xiang-Yang-；Xu-Wei-Beng-；Ma-Hui
Structure and Microclimate Effects of Shelter-belt on Farmland in Ningxia
Through the investigation on the structure and ecological benefits of shelter-belt on farmland in Ningxia and the analysis of comprehensive weight index, that the important roles played by large net, multi-shelter belt and mixed multi-tree-species in the construction of protection forests is explained. The results show that the wind protection effect of shelter-belt on farmland is better when its porosity reaches 35%～45% and its characters determine the law of variation of wind speed. By the redistribution of solar radiation, shelter-belt on farmland has prominent temperature effects on the surface of the soil and plant, which can prevent the crop from heating. Shelter-belt for farmland can increase air relative humidity and soil moisture. The mechanism is related to its wind control function.
2004 Vol. 2 (4): 82-86 [
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1484
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2464KB] (
1330
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87
CHEN Jing-Yu-；Zhou-Xin-Cheng-；Zhang-Wei-Hua-；Li-Wen-Zhong-；Li-Yong-Liang
Effects of Plant Root System on the Anti-scourability of Soil in the South of Qilian Mountain
The studies on root system of plant community and soil anti-scourability reveals the rule of it where in the same soil type, site condition, vegetation type and age of stand between plots. The effect of plants' root system to soil anti-scourability is analyzed. That plants' rich root system can change the character of soil is concluded. It can increase soil organic matter, aggregate content of water stability and non-capillary soil porosity, decreasing soil bulk density. Soil and soil permeability can be loosed and enhanced by the increase of organic matter, and then, soil anti-scourability can be enhanced. To control soil erosion, afforestation and forest management should be enhanced in Datong county, Qinghai province.
2004 Vol. 2 (4): 87-91 [
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1758
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1KB] [
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2655KB] (
1211
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92
ZHANG Ying-；Tu-Xin-Xiao-；Xie-Bao-Yuan-；Song-Wei-Feng
The Present Situation and the Developing Tendency in the Rational Allocation of Water Resources
To be sure the sustainable utilization of water resources, it has become the most important resources and environment problem of Chinese economy and society development in 21th century. If the conflict between supply and demand of water resources is resolved and realize the sustainable utilization of water resources, it will be necessary to rationally allocate the water resources. The research content, theory, method and technique in water resources rational allocation are mainly discussed; the international research process and problem in existence are analyzed and the developing tendency in the rational allocation of water resources is predicted.
2004 Vol. 2 (4): 92-97 [
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] (
1569
) [
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3580KB] (
1441
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98
WU Feng-Dong-；Gu-Rui-Yan-；Xiao-Yu-Bao-；Xu-Ting-Juan
Present Condition and Countermeasures of Eco-restoration in Northern Shaanxi: A Case Study of Yulin
Northern Shaanxi is one of the keystone areas of eco-environment conservation in China with severe soil and water loss and vulnerable eco-environment. So, it will have strong demonstration for eco-environment conservation in Loess Plateau to do well in ecological restoration engineering. Aiming at the problems which exist in eco-environment restoration conditions taking Yulin as an example, three countermeasures are presented in eco-environment restoration in this area, one is to follow the order of nature, the second is to do well in subarea work for ecological restoration, to adjust measures to local conditions and construct ecological structure in reason, the last one is that eco-environment conservation must combine with local economic development.
2004 Vol. 2 (4): 98-101 [
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1408
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2411KB] (
1452
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102
CHEN Xin-Jun-；Zhang-Guang-Can-；Zhou-Ze-Fu-；Ma-Shu-Sheng-；Li-Xiao-Lei-；Zhang-Chu-Yong
Diurnal Variations and Response to Light of Gas Exchange Parameters of Clove (Syringa oblata Lindl.) Leaf in Loess Hilly Region
With CIRAS-2 portable photosynthesis system, diurnal variations and response to light of gas exchange parameters of clove (
Syringa oblata
Lindl.) leaf in four years old were studied under different soil moisture content in the loess hilly region in semi-arid area. The results indicated the Photosynthetic rate(
P
n
),
T
r
anspiration rate(
T
r
), Water Use Efficiency of Leaf(
WUE
), Stomatal conductance(
G
s
) and Intercelluar CO
2
concentration (C i) had clear threshold value responses to soil moisture and Photosynthetic Active Radiation(PAR). The fitting range of Mass Water Content(
MWC
) is 15 0%～19 5%, Relative Water Content(
RWC
) is between 58 8% and 76 6%, the fitting PAR range is 600～1000μmol photons·m
-2
·s
-1
. In that range of
MWC
and PAR, Syringao blata lindl can get higher
P
n
and
WUE
, and will not waste water because of high T r, and the Pand WUE will weaken out of those range. The lowest MWC is about 11 6%(
RWC
is 45 7%), and the corresponding highest
PAR
is about 800μmol photons·m
-2
·s
-1
, the falling of
MWC
or the increasing of
PAR
will lead to serious aridity stress and high light stress. The results showed that in the hilly-gully region in semi-arid area,
Syringa oblata
Lindl. should be planted in the ubac rather than in the abret, or be planted under other trees to form mixed forest rather than pure forest, which may has higher productivity and effects.
2004 Vol. 2 (4): 102-107 [
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1407
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2938KB] (
1019
)
108
XIAO Hui-Jie-；Wu-Feng-Dong-；Gu-Rui-Yan
Ecological Restoration and Reconstruction in Sanchuanhe Watershed
Soil erosion is the main form of ecological environment deterioration in Sanchuanhe watershed, and it is the key factor restricting economy from developing of the watershed. Based on actuality, cause and harm of soil erosion and water loss in Sanchuanhe watershed, the basic countermeasures of ecological restoration and reconstruction are put forward according to principle of restoration ecology.
2004 Vol. 2 (4): 108-111 [
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1536
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2662KB] (
1284
)
112
GUO Xiao-Beng-；Shu-Jin-Zhao-；Zhou-Xin-Cheng-；Ding-Guo-Dong-；Guo-Jian-Bin
Technology and Application of Slope Bio-technique
The development of slope bio-technique is reviewed, and the development status of slope bio-technique on theory at home and abroad is introduced. The present condition and existent problems of slope bio-technique in China are also analyzed and the research countermeasures of slope bio-technique and countermeasure in the future are given out.
2004 Vol. 2 (4): 112-116 [
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1331
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2827KB] (
1110
)
117
TU Xin-Xiao-；Chen-Li-Hua-；Niu-Jian-Zhi-；Diao-Yu-Chao
Hydrological Effects of CWD in Sub-alpine Dark Coniferous Ecosystem of Upper Reaches of Yangtze River
The volume of coarse woody debris (CWD) in dark coniferous ecosystem of upper reaches of Yangtze river amounts to 101 74?m 3/hm 2. There are remarkable differences among different succession community of the fallen tree and snag in terms of their volume and decay degree and decay degree of the fallen. The distribution trend generally abides by the rule of increasing with the succession. The decay degree obeys normal distribution. The second, the third and the fourth degree of fallen tree snag, and CWD account for 86.12%, 78.40% and 79.65% wlume of the total volumes of fallen tree, snag and CWD respectively. The water-absorption and water-losing process is the exponential function of the time. With the decay degree's decreasing, the capacity of CWD water-holding decreases. The natural and saturated water-holding capacities of the first degree of CWD amount to 100%, while those of the fifth can attain to three and a half times to seven and a half times of dry-weight itself respectively. The water-holding function of fallen tree almost amounts to 10 times of that of snag. Totally, 7.41mm of precipitation can be hold by CWD under the natural conditions in the dark coniferous ecosystem whereas 9.91mm of precipitation can be hold if all the CWD are saturated, which is an important contribution to the water regulation role of dark coniferous ecosystem of upper reaches of Yangtze river.
2004 Vol. 2 (4): 117-122 [
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1335
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1215
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