中国水土保持科学
Home
About Journal
Editorial
Publication Ethics
Instruction
Subscription
Contact Us
中文
Editorial 1
Editorial 2
Editorial 3
Editorial 4
For Author
Scope for Articles
Writing Format
中国水土保持科学
Paper Search
Adv Search
2011 Vol.9 No.5
Published 2011-10-31
Articles
1
TAN Zhen-Hua, WANG Tie-Li, LIU Dun-E, YUAN Yan, CHEN Gao, WANG Sha, SHEN Nan, JIAO Nian
Response of runoffinduced sediment discharge to hydrodynamic parameters of rill on loess hillslope
Runoffinduced sediment discharge is one of the most important process of erosion and sediment yield. It is important to clarify the relationships of runoffinduced sediment discharge and hydrodynamic parameters of rill flow on loess hillslope. In this paper, the relationships were studied by experiment of simulated rainfall and constant flow using group plots. Results showed that: 1) In single rainfallrunoff event, the response of sediment transport modulus to mean hydrodynamic parameters was given as follows: mean unit energy (
R
=0.99)>mean stream power (
R
=0.88)>mean stream shear stress (
R
=0.82)>mean unit stream power (
R
=0.76). 2) During the rainfallrunoff process, the response of the sediment transport rate to stream shear stress (
R
=0.88) was greater than stream power (
R
=0.47)，and the correlations of sediment transport rate with unit energy and with unit stream power were weak. The relationship of stream shear stress and the sediment transport rate could be expressed by power functions.
2011 Vol. 9 (5): 1-6 [
Abstract
] (
1624
) [
HTML
1KB] [
PDF
563KB] (
1488
)
7
WANG Nian-Zhong, CHEN Bei
Development of gully erosion in Northeast China and its effects on the national food security
By analyzing the gullies development in number, length, density, area (mainly referring to the lost cultivated land) and their distribution in river basins of typical black land zone from 1965 to 2005, we studied the effect of gully erosion on food security, Northeast China. Results show that: 1) From 1965 to 2005, gully area, gully number and total length of gully increased by 85.27km
2
, 13168, and 6183.70km, respectively. Gully density increased from 0.034km/km
2
to 0.193km/km
2
during the 40years. The gully number, area and density increased rapidly. 2) Different land use led to different gully development rate. For cultivated land, gully area, gully number, length of gully and gully density increased by 81.83km
2
, 12825, 5981.23km and 0.271km/km
2
respectively; for woodland and other land use, they increased by 3.44km
2
, 343, 202.47km and 0.02km/km
2
respectively. 3) A great proportion of gully occurred in the cultivated land in typical black land zone, with area for 96% and number for 97.4%. Gully mainly occurred on cultivated land in typical black soil zone, Northeast China, which would have adverse effects on the national food security.
2011 Vol. 9 (5): 7-10 [
Abstract
] (
1618
) [
HTML
1KB] [
PDF
581KB] (
1636
)
11
MIAO Quan-An, CAO Cou-Gui, HONG Jin-Beng, GAO Chao, LI Cheng-Fang
Effects of different crop systems on soil splash erosion from sloping land in Danjiangkou Reservoir region
A field experiment was conducted on typical sloping land in Dangjiangkou Reservoir region. The effects of different crop types on soil splash erosion were studied and its relationship with crop height, crop cover, soil moisture and soil temperature at 5cm depth were discussed. The results indicated that planting crop had significant effect on soil splash erosion. There was no significant difference in soil splash erosion among different treatments during the primary stages of crop growth, but planting crop could significantly decreased soil splash erosion in the vigorous stages of crop growth. Compared to CK, the decrease amount of soil splash erosion in
Ipomoea batatas
treatment was the largest, followed by
Cortex cinnamom
and
Zea mays
L., and in
Rhizoma curcumae
Longae treatment was the least. Regression analyses indicated that soil splash erosion greatly correlated with crop cover, soil moisture and soil temperature with quadratic equation. Therefore, it can be concluded that planting crop could change the spatial pattern of sloping land, which will affect the redistribution of rainfall.
2011 Vol. 9 (5): 11-14 [
Abstract
] (
1507
) [
HTML
1KB] [
PDF
688KB] (
1487
)
15
MA Ning, DIAO Bang-Yuan, WANG Fu-Gui, MA Wei-Xing, DONG E-Wei
Preliminary study on sediment sources of watershed under control of water loss and soil erosion： Taking Xiwuselanggou Watershed of Huangfuchuan Basin as the example
Based on the highresolution images obtained from remote sensing, this study were conducted in Xiwuselanggou Watershed of Huangfuchuan Basin. GIS technology was applied to determine the upper edge line of the watershed. The watershed was divided into two relief types, i.e. the gully area and the interrill land. Sediment sources of the watershed, where control of water and soil loss is ongoing, were compared by two aspects. The first aspect was according to the amount and distribution of local gully erosion and surface erosion, and their influential factors including cutting intensity, as well as water and soil conservation measures and land use mode, gradient, and vegetation coverage, etc.; the second aspect was based on the observation data of the rainfall stations, port stations, and runoff plots distribution in the watershed. Both the two aspects showed that local sediment was mainly produced from the gully area, and soil erosion amount of the gully area was 2.73 times as much as that of the interrill land, making up about 73% of the total erosion amount in the watershed.
2011 Vol. 9 (5): 15-19 [
Abstract
] (
1400
) [
HTML
1KB] [
PDF
1291KB] (
1310
)
20
ZHANG Hong-Zhi, SHU Qing-Ke, DIAO Lei-Lei, KUANG Gao-Meng, XIE Jing, LI Tian
Soil chemical properties of microtopography on loess slope in Northern Shaanxi Province
Due to erosion and other reasons, loess slope in Northern Shaanxi occurred unevenness, which formed a variety of microtopography and led to differences in soil chemical properties. The soil chemical properties of the microtopographies were investigated and analyzed in this paper. Results showed that: 1) compared with undisturbed slope, soil chemical properties of five types of microtopography in study area were improved to some extent. Contents of soil organic matters in the 0-20cm soil layer for the five microtopography types were given as follows: collapse> gully, platform and ephemeral gully(EG)>undisturbed slope and scarp. 2) For the five types of microtopography, the distribution of total N agreed with the soil organic matters, and there was no big difference between total P and total K. 3) Except for scarp, available nutrients in collapse, gully, ephemeral gully (EG) and platform were higher than those in undisturbed slope. 4) Cationic exchange capacity decreased with soil depth and performed the order of ephemeral gully(EG)> collapse> gully> undisturbed slope> platform> scarp. There were no significant difference between CaCO
3
and pH. 5) From the analysis of grey correlation on the soil chemical properties of three soil layers of the five types of microtopography and undisturbed slope, it can be concluded that the collapse and platform gained the closest correlation, but undisturbed slope and scarp were the worst.
2011 Vol. 9 (5): 20-25 [
Abstract
] (
1413
) [
HTML
1KB] [
PDF
783KB] (
1449
)
26
JIANG De-Wen
Interpretation to the legal provisions system of new
Soil and Water Conservation Law of the People’s Republic of China
The revised
Soil and Water Conservation Law of the People’s Republic of China
was passed by the standing committee of the National People's Congress on December 25, 2010. The revision of the law system and prominent characteristics can be reduced to 10 strengthening aspects, including Soil and Water Conservation goal responsibility of government, legal status of Soil and Water Conservation planning, prevention of soil erosion, management of Soil and Water Conservation program for construction project, erosion control ratio and quality, Soil and Water Conservation input mechanism, Soil and Water Conservation supervision and management, punishment against on the illegal behavior, responsibility investigation and substitution perform, and etc.. The revision and promulgation of
Soil and Water Conservation Law of the People’s Republic of China
marks that the Soil and Water Conservation successful career development have entered into a new historical stage.
2011 Vol. 9 (5): 26-30 [
Abstract
] (
1595
) [
HTML
1KB] [
PDF
762KB] (
1625
)
31
HONG Yong-Yang, DUAN Wen-Biao
Evaluation on water conservation capacity of three main forest types in southern slope of Xiaoxing’anling Mountains
In this paper, to evaluate the water conservation capacity on the litter layer and soil layer of three main forest types in southern slope of Xiaoxing’anling Mountains, the eleven indices affecting water conservation capacity were selected, and analytic hierarchy process (AHP) method was employed. The results showed that natural poplar and birch mixed forest performed the best water conservation capacity (0.4271), followed by larch plantation (0.3687), and natural Korean pine forest was the weakest (0.2042). The results were agreed with the reality. The AHP method can be used to give quantitative evaluation on water conservation capacity in different forest types.
2011 Vol. 9 (5): 31-36 [
Abstract
] (
1414
) [
HTML
1KB] [
PDF
843KB] (
1578
)
37
CAO Li-Hua, LIU Ge-Man, DIAO Shi-Wei
Effect of soil conditioners on water stability of soil aggregates and its mechanisms in loessal soil
Soil conditioners, which are widely used in preventing soil and water losses, could improve soil physical structure and provide good conditions for plant growth. PAM, water super absorbent polymer，βcyclodextrin and humic acid were used as soil conditioners in this paper. The results showed that all of the four conditioners could promote the formation of >0.25mm waterstable aggregates. Within the test range of 0.05%-0.40%, the improved effect showed PAM>βcyclodextrin >water super absorbent polymer > humic acid, and the fractal dimension of aggregates decreased largely, especially for the PAM. All of the four conditioners could reduce the soil bulk density at the low concentration. From soil particle size distribution, it can be observed that 1mm soil waterstable aggregates, especially >5mm soil waterstable aggregates obviously, which will explain how PAM worked on soil structure. In the four conditioners, PAM played the best role in improving loessal soil structure. This paper discovered the effect and mechanism of soil conditioners on loessal soil, which will provide theoretic basis of using and improving soil conditioners reasonably.
2011 Vol. 9 (5): 37-41 [
Abstract
] (
1398
) [
HTML
1KB] [
PDF
858KB] (
1408
)
42
WANG Shi-Yong, TU Xin-Xiao, GU Guo-Dong, SONG Sai-Ming, XU Juan, LI Qiang-Yun
Hydrological effects of forest litters of different forests in Beijing mountainous area
The hydrological effects of forest litters in
Pinus tabulaeformis, Robinia pseudoacacia
, and
Platycladus orientalis
forest communities in Zhuanghugou watershed, located in Tanghekou Town, Huairou District of Beijing, were studied in this article. Results show that: 1) The litters amounts and total thickness in
Pinus tabulaeformis
were the largest, 6.37t/hm
2
and 4.0cm respectively, followed by
Robinia pseudoacacia
, and the least were in
Platycladus orientalis
. 2) The largest waterholding capacity of litter was
Robinia pseudoacacia>Platycladus orientalis> Pinus tabulaeformis
, and the largest waterholding rate was
Robinia pseudoacacia > Pinus tabulaeformis > Platycladus orientalis
. In the early half hour of water absorption of litter, waterholding rate increased rapidly, and then slightly decreased over time after the 4th to 5th hour. The effective water holding depth in
Robinia pseudoacacia
was the highest (2.6mm), and the lowest was in
Platycladus orientalis
(1.0mm). 3) It was evident that forest litters could prolong the surface runoff process. In the same slope degree, runoff generation time was given as follows:
Robinia pseudoacacia > Pinus tabulaeformis > Platycladus orientalis
>bare land, and was runoff velocity bare land>
Platycladus orientalis > Pinus tabulaeformis > Robinia pseudoacacia
. The runoff amount in bare land was 1.04 to 1.46 times as great as the three kinds of forests.
2011 Vol. 9 (5): 42-47 [
Abstract
] (
1383
) [
HTML
1KB] [
PDF
894KB] (
1725
)
48
HU Hua-Sen, YUN Lei, BI Hua-Xin, BAO Biao, GAO Lu-Bo, LIU Li-Xia, SHU Yue, WANG Xiao-Yan
Distribution characteristics of soil nutrients and their depth of edge influence in
Robinia pseudoacacia+Medicago sativa
silvopastoral system:A case study in the loess region of western Shanxi Province
This study was conducted in Loess Plateau of western Shaanxi Province, Northwestern China by taking
Robinia pseudoacacia+Medicago sativa
model as research object. Soil nutrients including organic matters, total N, available P and available K in 0-40cm soil layer were measured and analyzed, The distribution characteristics of these soil nutrients and their depth of edge influence were studied to provide theoretical basis for soil nutrients improvement, nutrient research of different land use types and management of silvopastoral system in this region. Results showed that: 1) The four nutrients indicators fluctuated on a large span in the silvopastoral system. The distribution characteristics of soil nutrient in different patches occurred difference to some extent. In general, the contents of soil nutrient indicators in
Medicago sativa
field were higher than those in
Robinia pseudoacacia
field. 2) Distribution characteristics of soil nutrients in
Robinia pseudoacacia+Medicago sativa
silvopastoral system were given as follows. The soil nutrient contents were higher in 0-20cm soil layer than those in 20-40cm, but the their changes were different. Horizontally, in the
Medicago sativa
field, apart from the content of total N without significant change, other soil nutrient indicators all increased with increasing distance from forest edge to grass area. Comparably, in the
Robinia pseudoacacia
field, organic matters, total N, available P decreased with increasing distance from forest edge to forest area, but available K showed an opposite trend. 3) According to the Principle Component Analysis, boundary soil nutrient in the silvopastoral system showed an edge effect of 4m in grass exterior to 3m in forest and a width of 7m.
2011 Vol. 9 (5): 48-53 [
Abstract
] (
1709
) [
HTML
1KB] [
PDF
932KB] (
1239
)
54
WANG Ji-Beng, DIAO Mei, CHENG Bi, JIANG Lei, WANG Ran
Temporal variations and trend analysis of runoff in Qingjianhe River in Yellow River midstream area in the past 50 years
Based on the data set of runoff of the Yanchuan Hydrological Station, Qingjianhe River, in the past 50 years, annual unevenly distribution coefficient of runoff, complete accommodation coefficient, concentrative degree (concentrative period), variation coefficient and runoff extremum ratio of the station were calculated and analyzed, which indicated the annual and interannual variations of runoff. The longterm variation tendency of the runoff in the Qingjianhe River Basin was verified by the tendency analysis method. The results demonstrate that the annual analytic curve of annual distribution of runoff in Qingjianhe River Basin occurred unimodal curve, and the runoff mainly distributed during July to September, which accounted for 58% of average annual flow. Since 1990s, the annual unevenly distribution and concentrative degree had a gradual decrease. The interannual runoff in different periods varied so greatly to reach the peak of past 50 years after 2000. The annual runoff in this basin presented a significant downtrend, which was supported by the facts that 1980s was the remarkable turning point of the runoff from high to low water level period, and after 2000 runoff turned into the lowwater period and reached the lowest level in the past 50 years. The evolution of runoff in Qingjianhe River Basin shows the clear nonuniformity, periodicity and tendency, which is related with the rainfall and characteristic variation of underlying surface caused by restoring vegetation.
2011 Vol. 9 (5): 54-59 [
Abstract
] (
1542
) [
HTML
1KB] [
PDF
1044KB] (
1321
)
60
LI Yong-Sheng
Transpiration of
Platycladus orientalis
plantation and its relationship with environmental factors in limestone area, Taihang Mountains
In order to ascertain the transpiration variation of oriental arborvitae（
Platycladus orientalis
(L.) Franco）plantation and its relationship with environmental factors in limestone area of Taihang Mountains, flowbased transpiration was measured simultaneously with environmental variables, including soil volumetric water content(
W
v
)，photosynthetically active radiation（
P
ar
），relative humidity（
H
r
），air temperature（
t
a
）, wind speed (
v
w
) and rainfall (
R
). Transpiration rate showed unimodal diurnal variations with diurnal mean value 0.025-0.041mm/h and maximum value 0.078-0.150mm/h over the experiment period. Diurnal transpiration rate was significantly affected by
H
r
,
t
a
,
P
ar
and
W
v
（
P
<0.05）,which could give 87.7% variation together. The descending order of correlation degree was
P
ar
,
H
r
,
t
a
and
W
v
. Accumulative and mean daily transpiration of stand mean was 0.2-1.6mm and 0.7mm respectively. They were significantly affected by
H
r
,
t
a
,
P
ar
and
W
v
, which could give 64.3% seasonal variation together. The descending order of correlation degree was
P
ar
,
H
r
,
W
v
and
t
a
over the experiment period.
P
ar
had the most significant effects on daily transpiration, followed by
t
a
in most of period intervals.
H
r
and
W
v
had significant effects on daily transpiration only during the wetting and drying alternation intervals. Accumulative and mean monthly transpiration were 18.3-28.8mm and 21.8mm respectively. The seasonal variation of accumulative monthly transpiration occurred unimodal pattern with peak value observed in June. Accumulative monthly transpiration only greatly correlated with
P
ar
（
P
<0.05）.The seasonal（1 April to 30 September）total transpiration amounts to 130.5mm, representing 42.5% of rainfall over the period.
2011 Vol. 9 (5): 60-66 [
Abstract
] (
1429
) [
HTML
1KB] [
PDF
1023KB] (
1336
)
67
HU Jian-Peng, YANG Ji-Hua, LUO Meng-Da, LI Xing-Chen
Soil water storage efficiency of different stand types in Sandy Mountain of Shandong Province
The study on soil water storage of five stand types were conducted in Soil and Water Conservation Experiment Station of Linqu County. The results show that:
Robinia pseudoacacia
Linn.,
Acer mono
Maxim. and
Pistacia chinensis
Bunge. stands of more litter layer, which improved soil physical and chemical properties and increased soil water storage capacity after decomping. Compared to control, the increased saturated water storage in
Robinia pseudoacacia
Linn. was the largest by 549.8m
3
/hm
2
, followed by
Acer mono
Maxim. and
Pistacia chinensis
Bunge., 416.9 and 392.3m
3
/hm
2
respectively, and in conifers species such as
Pinus thunbergii
Parl.,
Platycladus orientalis
(Linn.) Franco were relatively not so much by 257.9m
3
/hm
2
and 223.7m
3
/hm
2
correspondingly. The correlation analysis between the amount of decomposed litter layer and 0-20cm soil physical and chemical properties shows that: the amount of decomposed litter layer were extremely significant correlated with soil organic matter content and soil noncapillary porosity, significantly associated with soil bulk density and total soil porosity, but not significantly related to the soil capillary porosity. The soil water storage efficiency of the five different stands decreased in the order of
Robinia pseudoacacia
Linn.,
Acer mono
Maxim.,
Pistacia chinensis
Bunge.,
Pinus thunbergii
Parl.,
Platycladus orientalis
(Linn.)Franco.
2011 Vol. 9 (5): 67-72 [
Abstract
] (
1505
) [
HTML
1KB] [
PDF
939KB] (
1391
)
73
NIU Gong-Yu, WANG Ke-Qi, LI Ta-Xin, WANG Ping, TANG Zuo-Xin
Effects of fertilizer application on N and P concentrations of soil water in slope land in Fuxian Lake Watersheds
To study the effects of fertilization and slope position on the variation of total nitrogen and total phosphorus concentrations, a field experiment was conducted in Fuxian Lake Watersheds in central Yunnan Province, Nine micro plots were arranged. Soil solution samplers of different depth were installed at different slope positions in the plots. Variation characteristics of total nitrogen and total phosphorus concentrations were studied. Results showed that: 1) With fertilizer amount increasing, average concentrations of total nitrogen and total phosphorus in soil water increased. At 1.5 times and 2 times of constant fertilization treatments, total phosphorus concentration of soil water at 0-100cm depth were 1.26 times and 1.63 times of constant fertilization. 2) Under the same fertilization treatment, total nitrogen and total phosphorus concentrations of soil water at bottom were larger than those at middle slope. Total nitrogen concentration of soil water at 0-50cm depth at slope bottom was 1.30 times of that at middle slope. Total phosphorus concentration of 0-100cm soil water at slope bottom was 2 times of that at middle slope. 3) Under the same fertilization treatment, total nitrogen concentration of soil water had a decline trend with depth deepening. Average total nitrogen concentration of soil water at 0-50，50-100cm，beneath 100cm were respectively 4.58，3.93，3.17mg/L. Total phosphorus concentration of soil water had a wavy decline trend over depth. Variation range of total phosphorus concentration was larger (0.010-0.021mg/L) at 0-100cm, smaller beneath 100cm (0.010-0.014mg/L). 4）Total nitrogen concentration should be controlled in 270.0kg/hm
2
, and total phosphorus concentration should be controlled in 61.2kg/hm
2
.
2011 Vol. 9 (5): 73-78 [
Abstract
] (
1378
) [
HTML
1KB] [
PDF
952KB] (
1463
)
79
XU Dong-Meng, HU Xiao-Lan, ZHANG Guang-Can, LIU Xia, TAO Xiao-You, HU Xu-Li
Multifractal analysis on soil particle size distribution for different vegetation types in Jiangzihe small watershed
For exploring the effect of vegetation types on heterogeneity characteristics of soil particle size distribution and soil structure, the composition of soil particles and its multifractal characteristic for five vegetation types of Jiangzihe small watershed were studied with laser particlesize analysis method and multifractal theory. The results show that: 1) The volume fractal dimension
D
and multifractal parameters Δ
α, R, f［α(-1)］- f［α
(0)］ and
f［α(1)］/ f［α
(0)］ are significant positively correlated with the content of clay particles, i.e., the higher the content of soil fine particles, the more heterogeneous the soil particle distribution and the greater singularities. 2) The fractal dimension and multifractal parameters of different vegetation types are give as the following order: the spinney and mixed forest (
Pinus massoniana+Quercus variabilis
)>tea plantation(
Camellia sinensis
)>bamboo forest (
Phyllostachys pubescens
)>paddy field, which means that the forest vegetation (protective forest) could improve the heterogeneity of soil texture and soil structure by raising the content of clay particles.
2011 Vol. 9 (5): 79-85 [
Abstract
] (
1487
) [
HTML
1KB] [
PDF
1058KB] (
1479
)
86
XU Kang, WANG Xiao-Hui, XU Meng-Chao, WANG Bang, GUAN Wen-Ban
Response of chronology of
Pinus armandi
to ecoclimate indicator in Liupan Mountain, Ningxia Province
The correlation analysis between chronology of
Pinus armandii
in Liupan Mountain and ecoclimate indicators was established to reconstruct the substitution data for surface moisture status from 1953 to 2003. The correlation analysis between chronology and single climatic factors (mean temperature and precipitation) showed that the radial growth was more sensitive to the temperature from May to July and the precipitation of March and May. Compared with the single climatic factors, the aridity index was a better ecoclimate indicator that could indicate the local complex surface conditions. Using regression equation between standard treering chronology and aridity index, surface conditions from 1953 to 2003 were reconstructed. The results showed that there were two relatively drought periods: 19531963 and 19932003, and the reconstructed series displayed significant cycles of 4-7 years. The aridity index increased gradually since 1980s, and the annual precipitation would be at lower level in a few years. The aridity index would be 23.5 in 2011, being still in the drought period.
2011 Vol. 9 (5): 86-90 [
Abstract
] (
1248
) [
HTML
1KB] [
PDF
984KB] (
1420
)
91
ZHANG Ting, CHEN Yun-Meng, WU Chun-Hua
Change of underground biomass and soil fertility with restoration stages of
Artemisia gmelinii
and
Stipa bungeana
in Loess Hilly Region
This study aims to better understand the interaction between typical vegetation in different succession stages and soil of Loess Hilly Region and to supply evidences for the initiatives of vegetation restoration. Based on field investigation and laboratory experiments, statistical methods of Stepwise Regression Analysis and Path Analysis were employed in this study. We studied the change of aboveground biomass, underground biomass and soil fertility of
Artemisia gmelinii
and
Stipa bungeana
in Loess Hilly Region with restoration stages and the relationship of aboveground biomass with environment factors. The results show that the aboveground and underground biomass of the two communities both increased with restoration stages, and so did their soil organic carbon, total nitrogen, total phosphorus and NO
3
N. The change trend of soil organic carbon and total nitrogen was largely agreed with community biomass, but the change trend of total phosphorus, NO
3
N was not very coherent with community biomass. The results of Stepwise Regression Analysis and Path Analysis suggest that factors affecting
Artemisia gmelinii
greatly were contents of soil organic matter, water and clay. Among the three factors, the former two factors performed positive effect, and the later had negative effect. For
Stipa bungeana
, altitude, slope position, restoration stages and total nitrogen were major factors influencing its biomass.
2011 Vol. 9 (5): 91-97 [
Abstract
] (
1560
) [
HTML
1KB] [
PDF
1030KB] (
1468
)
98
WEN Shi-Zhi, ZHANG Xi, YANG Li-Li
Nutrient return of
Liquidambar formosana
in suburbs of Changsha City
utrient return of
Liquidambar formosana
plantation was studied by means of field investigation and laboratory analysis in this paper, which could provide theoretical basis for the management of
Liquidambar formosana
plantation and research of the nutrient cycling. Results showed that: 1) The annual amount of litter in
Liquidambar formosana
plantation was 4935.6kg/hm
2
, and the amount of each component was in that order: leaf＞branches＞fruit＞debris. 2) The annual nutrient return amount of litter was 111.849kg/hm
2
. The order of return amount of each element was N＞Ca＞K＞Mg＞P. The return amount of litter in each component was in that order: leaf＞branch＞fruit＞debris. 3) The annual return amount of leaching nutrients was 105.823kg/hm
2
. The order of each leaching element was Ca＞K＞Mg＞P＞N. 4) The total annual nutrient return amount in
Liquidambar formosana
plantation was up to 217.672kg/hm
2
. The order of each return element was Ca＞N＞K＞Mg＞P. It can be concluded that the return of nutrients of litter through rainfall leaching can not be ignored in rainy subtropical area.
2011 Vol. 9 (5): 98-103 [
Abstract
] (
1318
) [
HTML
1KB] [
PDF
993KB] (
1291
)
104
JI Yan-Bing, CHANG Qiang-Rui, LIU Meng-Yun, LIU Jing, CHEN Chao
Quantitative analysis of natural and anthropogenic effect on sandy desertification in the agropastoral transitional zone of northern Shaanxi Province in the near fifty years
Desertification is a complicated process affecting by variety of natural conditions and human activities. In order to analyze the function of natural and human activity in desertification process, the agropastoral transitional zone of northern Shaanxi Province was selected as a case study area.By employing principal component analysis method, the seven factors during 1949 to 2000 were chosen, including temperature, precipitation, wind speed, population quantity, livestock quantity, cultivated land area and industrial gross output, to analyze the intensity of nature and human activity factors quantificationally. The results showed that: 1) Predictions call for the climate to become increasingly warmer and drier over the next several decades. The average wind speed decreased during the period. The population, livestock populations and gross industrial output increased significantly from 1949 to 2000, but the per capita cultivated land decreased significantly in the same period; 2) In the desertification process, nature factors contributed to 13.6%, and human activity combining with nature factors contributed to 75.31% in the agropastoral transitional zone of northern Shaanxi Province; 3) Fortunately, local officials have recognized the negative effects of desertification and paid more attention to controlling desertification. Planting shrubs to improve vegetation coverage is the main approach used for desertification control. Two projections have been applied to the agropastoral region of northern Shaanxi Province to control desertification: the “Three North Shelterbelt Program” and the “GrainforGreen Project”.
2011 Vol. 9 (5): 104-109 [
Abstract
] (
1539
) [
HTML
1KB] [
PDF
1108KB] (
1388
)
110
DIAO Yong, SHU Pan-Feng, WANG Qian, CHEN Zhen, FAN Wei, YANG Chi-Tian
Effects of nitrogen absorption of
Vitex negundo
in different nitrogen fertilization levels
Taken
Vitex negundo
community in Taihang mountainous region as object, this paper studied the effects nitrogen absorption of
Vitex negundo
in different nitrogen fertilization levels. The main purpose of this paper is to discover the response of plant to different nitrogen environment. Results showed that：1) Both the contents of nitrogen in mature and withered leaves increased with increased nitrogen fertilization level, and the maximum values occurred at 32g/m
2
nitrogen fertilization level. Nitrogen fertilization had obvious effects on the content of phosphor in mature leaves with the maximum value being at 8g/m
2
, which was 2.29 times that of control. Whereas it had nothing to do with the content of phosphor in withered leaves. 2) Nitrogen fertilization could lead to the decrease of nitrogen resorption efficiency of
Vitex negundo
. The nitrogen fertilization was negatively correlated with nitrogen resorption efficiency, average decrease being up to 18.57%. But when nitrogen fertilization level was 4-8g/m
2
, the change of nitrogen resorption rate was not obvious. 3) The content of nitrogen in soil increased with increased nitrogen fertilization level. The maximum value of phosphor content in soil was at 4g/m
2
nitrogen fertilization level, and the content of phosphor decreased after that point. Nitrogen resorption efficiency of
Vitex negundo
negatively correlated with soil organic matter and soil moisture content.
2011 Vol. 9 (5): 110-114 [
Abstract
] (
1333
) [
HTML
1KB] [
PDF
992KB] (
1315
)
115
LI Jing-Jing, BAI Gang-Shuan
Mechanism of PAM on soil and water conservation and its development
Soil and water loss is one of the major environmental problems in China. As a high molecular polymer, PAM possesses flocculation and hydration effects, and thus could improve soil water infiltration and reduce surface runoff. PAM has no toxic effects on soil, and it could preserve fertilizer, increase yields, harvest rainfall, and has a broad application prospect in agriculture production. According to the function of PAM on soil and water conservation, this paper mainly introduces the soil and water conservation mechanisms of PAM, the key factors in application processes, application prospects, and existing problems. PAM owns various types, the soil and water conservation efficacy varies primarily with PAM types, application methods, and application quantity. In order to make full use of it, PAM should be inosculated closely with the local soil, climate, landscape, and vegetation in soil erosion control. Future researches should emphasize on building a universal soil loss equation model after the PAM application as well as developing new PAM products, so as to provide a theory basis for promoting the application of PAM in soil and water conservation.
2011 Vol. 9 (5): 115-120 [
Abstract
] (
1607
) [
HTML
1KB] [
PDF
992KB] (
1514
)
