To determine the effects of different forestlands returned from farmlands on soil organic carbon and carbon pool management level in karst areas, soil organic carbon (SOC) contents, density and carbon management index ( I_CM ) under six different land-use types, including conventional farmland (CT), abandoned farmland ( AF), farmland returned to plantations of Dodonaea viscosa ( DV), Zanthoxylum scandens (ZA), Toona sinensis (TS) and Vernicia fordii (VF), were studied in Huajiang gorge area of Guizhou Province. The results showed that: 1) compared with farmland, total organic carbon (TOC) content and density of lands converted from farmlands increased significantly (P<0.05). TOC in 0 -20 cm layer ranged from 13.00 -34.07 g/kg, with farmland the lowest while Toona sinensis the highest. TOC density in soil profile presented a trend of TS> VF>AF>DV>ZA >CT. 2)Both TOC content and TOC density decreased with the increase of soil depth in all land-use types. TOC contents in 0 -20 cm soil were 1.11 -1.37 times as high as the cross-sectional mean value, while SOC density in 0 -20 cm deep soil accounted for 35.68% -46.45% of the entire section, showing an obvious table cohesion. 3) Taking farmland as a reference, I_CM of all the other four converted lands were obviously greater than 1 except for Z. scandens. Vegetation recovery can effectively improve soil carbon pool management level, with T. sinensis and V. fordii having the highest efficiency. In addition, the change of LOC/ TOC ratio had the same tendency as the variation of TOC content. R_{L/ T} can be used as an important indicator to reflect the level of carbon management. In summary, returning farmland to forests has the potential of expanding capacity of carbon pool and improving soil quality; therefore, we should pay attention to selecting suitable restoration modes, increasing vegetation cover as well as reducing human disturbance.

Based on field survey and laboratory experiments, we compared soil organic carbon density and aboveground biomass of three types of grassland (meadow grassland, typical grassland and desert grassland) in Inner Mongolia, northern China, in order to provide reference for grassland protection and improvement of soil organic carbon sequestration capacity. The results are as follows. 1) The variation regularity of soil organic carbon density differs in each of the three types of grassland: it is 100 -180 g for the meadow grassland, 120 -140 g for the typical grassland and 60 -80 g for the desert grassland, while it is significantly different when the biomass is beyond the threshold value. 2) For different communities at the same biomass levels (80 - 100 g and 120 - 140 g), there exist some differences in soil organic carbon density, but without any obvious regularity. In brief, the improvement of biomass and prevention of grassland degradation would have positive effects on the increase of soil organic carbon density and improvement of soil organic carbon sequestration ability of grasslands.

The simulated rainfall experiment was conducted on three different land types, i. e. , Vetiveria zizanioides L. , ordinary grass and bare land, to analyze water and soil conservation effects and mechanism of V. zizanioides contour hedge. The results of a series of experiments showed that, compared with bare land, the V. zizanioides hedgerow reduced runoff by 21%, while the sediment yield was only 18% of that on bare land. The initial time-to-runoff of V. zizanioides contour hedge lagged behind prominently. With the rainfall intensity increasing, the effect of reducing runoff and sediment was more significant. The effect of reducing runoff and soil erosion was controlled by developed root system which improved soil structure, maintained higher water infiltration capacity, and thus reduced surface runoff. The huge aboveground biomass weakened the kinetic energy of raindrops, and reduced their impact on soil particles.

The study was conducted on Robinia pseudoacacia and Pinus tabuliformis forestlands of different slope aspects in Caijiachuan watershed, a loess region of western Shanxi Province. Based on the located observation of soil moisture at 0 -200 cm soil layer of fixed sample plots in R. pseudoacacia and P. tabuliformis forestlands from 2005 to 2012, optimal partition for ordinal specimen method was used to analyze the annual and interannual changes of soil moisture in R. pseudoacacia and P. tabuliformis forestlands, and the influence of precipitation distribution on annual and interannual changes of soil moisture in R. pseudoacacia and P. tabuliformis forestlands was discussed. The results showed that: 1) the annual dynamics of soil moisture in R. pseudoacacia and P. tabuliformis forestlands in the study area could be divided into four stages: stable stage, fluctuating stage, accumulative stage and consumption stage; in sunny slopes, the soil moisture condition of R. pseudoacacia forestland was similar to that of P. tabuliformis forestland, while in shady slopes the soil moisture condition of R. pseudoacacia forestland was the best; 2) the soil moisture deficit amount of P. tabuliformis forestland was less than that of R. pseudoacacia forestland in drought years, and during the interphase period of drought years and normal years, the soil moisture of P. tabuliformis forestland recovered faster than R. pseudoacacia forestland; 3) the annual precipitation distribution evenness was inversely proportional to the annual fluctuation range of soil moisture in R. pseudoacacia and P. tabuliformis forestlands, while the interannual change of soil moisture content in R. pseudoacacia and P. tabuliformis forestlands lagged behind the interannual change of precipitation. The suggestion of planting P. tabuliformis in sunny slopes and R. pseudoacacia in shady slopes was proposed for the vegetation rehabilitation in the loess region of western Shanxi Province.

In order to explore the effect of different forest vegetation types on rainfall redistribution in Three Gorges Reservoir area, we choose evergreen broadleaf forests and conifer-broadleaf mixed forests in the reservoir area as research objects, which are located near Badong County in the upper section of the reservoir of Hubei Province, Simian Mountain and Jinyun Mountain in the lower section of the reservoir in Chongqing. Using the observation data of rainfall, throughfall and stemflow for the 52 measured rain events in Jinyun Mountain of Chongqing from June to September in 2012, the canopy interception model was built up. Then we analyzed the characteristics of rainfall redistribution and compared the precipitation redistribution characteristics in Badong County with that in Simian Mountain. The result shows that the throughfall has a significant linear relationship with rainfall in the evergreen broadleaf forests and conifer-broadleaf mixed areas of Jinyun Mountain, Simian Mountain and Badong County. What is more, the amount of canopy interception has a significant exponential relationship with rainfall. According to the equation, the required minimum rainfalls to create throughfall in these areas for broadleaf forests are 1.0mm, 1.8 mm and 2.6 mm separately; on the other hand, it requires 1.1 mm, 3.0 mm and 1.1 mm for conifer-broadleaf mixed forests in the same areas. The average interception rate of conifer-broadleaf mixed forests is greater than the average entrapment rate of evergreen broadleaf forests at these locations. Under the same rainfall condition, the canopy interception rate of conifer-broadleaf mixed forests descends in the order of Jinyun Mountain in Chongqing (46.00%), Simian Mountain (41.42%) and Badong County in Hubei Province (22.30%); such ranking for broadleaf forests is Simian Mountain (28.78%), Jinyun Mountain in Chongqing (23.09%) and Badong County in Hubei Province (21.69%).

Vegetation restoration on purplish soil is one of the vegetation recovery challenges in China. In order to test the effects of Eulaliopsis binata vegetation on the improvement of purplish soil habitat, species diversity of the community that was planted with E. binata in correlation with the change of soil environmental factors was studied for the purpose of finding the most suitable recovery mode. A field survey was conducted in communities with different recovery modes (artificial restorations I, Ⅱand natural restoration Ⅲ) in mid July 2010 in Songlin, Hunan Province. All the collected data were analyzed utilizing TWINSPAN and RDA. The results show that 1) the species diversity are mainly influenced by the amount of total nitrogen, organic matter in soil, slope position and recovery mode and 2) the Gleason richness indices of upper slope and lower slope in artificial restoration Ⅱwere 2.171 and 5.863, respectively, followed by artificial restoration I and natural restoration Ⅲ. And the soil total nitrogen and organic matter in artificial restoration Ⅱincreased significantly. Therefore, the artificial restoration Ⅱtends to be more effective when using E. binata for vegetation recovery.

This paper took the “7·10”super-huge debris flows in Jian River section of Beichuan as the research object, analyzed the disaster types, spatial distribution, disaster characteristics, disaster mode and controlling factors. The results showed that: 1) rich provenance and heavy rainfall were the main causes to the disasters which were characterized by clustered spatial distribution and obvious chain effects, and the scales were mainly small or medium; 2) compared with other regions, debris flows had low densities ranging from 1.69 -1.91 g/ cm³, and they were mainly transitional types. The debris flows also had a significant amplification effect, and the rates of flow were 1.9 - 8.5 times that of pre - earthquake. Finally, given the characteristics and failure mode of disasters, some suggestions are proposed in order to relieve mountain hazards.

In order to understand the growth of planted vegetation in the slope ecological protection engineering, we took an actual project as study case, by using the technology of planting material spraying (PMS) as application background of mine slope greening, and conducted tracking survey on three slopes with different aspects and gradients within five years after vegetation planting concerning the main community characteristics like species, coverage and height. The results show that: 1)During the first year since vegetation planting, the general quantitative characteristics of plant vegetation was simple composition and inconspicuous vertical structure. Robinia pseudoacacia, Lespedeza bicolor, Cynodon dactylon, Medicago sativa and Festuca elata had better growth than other species. 2) After five years of vegetation rehabilitation, the vegetation restoration effect was good. The diversity and richness were increased and the dominance index decreased, and uniformity tended to be stable. Vegetation community with a strong soil fixing effect was formed as perennial herbs + L. bicolor + R. pseudoacacia. The development of grass root system was good. Legume species presented a dominate advantage. 3) During the wintering and summering periods, part of F. elata showed lodging phenomenon. A small amount of R. pseudoacacia leaves withered. Compared with other plants, the mortality of C. bipinnata was higher.Most plants had a good performance of resisting extreme weather conditions. The plant community was gradually formed with a strong soil fixing effect and good landscape effect.

A national nature reserve information management system has been developed based on GIS in order to improve its comprehensive management and service level, and to further integrate and develop information resources. Experiments and demonstration research were conducted in Xiaowutai Mountain National Nature Reserve. The results show that the system including three layers of structure system, four databases, eight major functional modules and six basic functions is able to meet management needs of the reserve. The system achieves multi-source heterogeneous data fusion and comprehensive integration, and promotes business collaboration and data sharing. It combines qualitative analysis, quantitative calculation with visual display to achieve space integrated management mode of information resources in the reserve. The system can provide a reference for information management of national nature reserves in China.

Enlightened by the antifreezing improvement of cement-soil composite, and considering the characteristics and functions of vegetation-concrete mixture, we chose palm fiber, silicon powder and surface active agent as the antifreeze raw materials of the vegetation-growing concrete. Based on the antifreezing test to the concrete, the optimum antifreeze composite ratio is put forward through the evaluation of relative dynamic elastic modulus and mass loss rate in the process of freeze-thaw cycles. When the mass ratio of palm fiber, silicon powder and surface active agent is 1:3:0.05, and the additive amount reaches 1.5% of the weight of the plant generates, the best effect will be obtained. Our study will provide theoretical foundation for slope ecology restoration in alpine region.

Surface drip irrigation is the most advanced method of irrigation to date, which enables the application of appropriate amounts of water to the soil through drippers. Study of soil water movement under infiltration of point source drip irrigation plays an important role in the promotion of drip irrigation technology. An indoor soil bin was designed in this study. Time domain reflectometry (TDR100) probes and tensiometers were adopted to measure soil water contents and soil water potential, respectively. The infiltration rates and wetting front interference under double point source drip irrigation emitters were analyzed. With the distance apart from drip increasing, the soil moisture of wetted volume from drip irrigation was reduced, and the soil moisture of wetted front on the intersection side was not smaller than the soil moisture of similar wetted depth. The soil water content (SWC) of 5 -35 cm layer reached 0.315 cm³ / cm³ rapidly during the irrigation phase. The soil moisture of the top layer gradually decreased, the soil moisture of sublayers gradually increased, and the rate of change of soil moisture slowed down in the redistribution phase. Our study would help in designing surface drip systems for efficient water use with minimum drainage.

This study focuses on the representative region implementing the policy of returning farmland to forests at Uxin Banner in Ordos ( 2000—2008 ). Geo-Information System ( GIS ) and Data Envelopment Analysis (DEA) are applied to explore the correlation between achievements of this policy and the efficiency of implementation. Further analysis has reflected the differences of policy efficiency between regional scale and individual scale and helps us to find out the key factors which play significant roles in the implementation of the policy of returning farmland to forests. The results show: 1) Galutu Town has a high efficiency, for its high resident income, while for the towns with lower income, such as Wudinghe Town and Tuke Town, the efficiency of the policy is low. Different livehood types have difference in efficiency. The efficiency of non-farming families seems to be the highest. 2) The research shows that highly urbanized regions are fit for the policy of returning farmland to forest project, while the efficiency of the policy in farming areas seems to be a little lower. 3) The policy should focus on the non- farming families, and we should pay attention to the influence of the policy on the farming families and multi-livehood families. 4) To make the policy of returning farmland to forest sustainable, we must change the current compensation measures, establish a complete security mechanism about the retraining and transposition of the manpower. The point is, we must reduce the conflicts between the development of the area, the increasing income and the policy of returning farmland to forest.

This study was designed to evaluate economic benefits of 1-to 8-year-old Malus pumila and crop intercropping systems. The monoculture of 1-to 8-year-old Malus pumila and the systems of Malus pumila intercropping with other crops such as Glycine max, Arachis hypogaea, Setaria italica and Zea mays in Jixian County of Shanxi Province were selected as research objects. Costs of production and economic incomes of the intercropping systems and monoculture way were quantitatively analyzed, and economic benefits of Malus pumila-crop intercropping systems were evaluated comprehensively. With the increasing age of Malus pumila trees, annual production costs of four intercropping systems increased from 3 900 - 5 200 to 10 200 - 12 000 yuan/ hm², while the annual economic incomes declined first from 10 900 - 14 400 to 4 700 - 5 700 yuan/ hm² and rose again to 14 100 - 16 900 yuan/ hm². Annual economic benefits of the intercropping systems presented a tendency of firstly rising and then descending with the aging of Malus pumila trees in the entire intercropping period; nevertheless, the economic benefits of the 1-to 7-year-old Malus pumila-crop intercropping systems were always greater than that in the Malus pumila monoculture system before the eighth year when it was reverse. To obtain the maximum economic benefit of intercropping, it is suggested that corn should be intercropped in 1-to 4-year-old Malus pumila tree rows, Setaria italica be intercropped in 5-year-old Malus pumila tree rows, Arachis hypogaea be intercropped in trees rows under 6-to 7-year-old Malus pumila tree rows, and intercropping should be ceased for 8-year-old Malus pumila trees. However, ecological benefits must be considered in practical production of intercropping systems in order to realize integration of immediate and long-term benefits.

In order to reveal the evolution of karst region after the returning farmland to forest project, six types of restored plantations including Castanea mollissima, Eucalyptus robusta Smith, Pinus massoniana Lamb, Zenia insignis Chun, Amygdalus persica Linn, and Illicium verum in Pingguo County of Guangxi Zhuang Autonomous Region were studied, and a seven-year grassland under enclosure was taken as control. The biomass allocations of different plantations were compared and biomasses were scored. Results showed that: 1) Total biomass per unit area ordered from high to low as C. mollissima > E. robusta > I. verum > P. massoniana > A. persica > Z. insignis. 2) For each type of restored plantation, the biomass of aboveground part is larger than that of the underground part. 3) The biomass of the herb layer is larger than that of the shrub layer in most of plantation types, but lower than the biomass of the seven-year grassland; 4) The dry litter weight per unit area ranked from large to small as C. mollissima > E. robusta > A. persica > Z. insignis > I. verum > P. massoniana; 5) Biomass composite scores ordered from high to low as I. verum > C. mollissima > E. robusta > P. massoniana >A. persica > Z. insignis. This project of returning farmland to forest can maintain ecological safety and promote the harmony between human and the nature, and still requires a long-term construction. Analysis of the ecological benefits of returning farmland to forest project has great significance to the nature and human.

The paper measured leaf area density (LAD), leaf area index (LAI), and diffuse non-interceptance ( DIFN) of Vitex negundo var. heterophylla canopy using LAI-2200 canopy analyzer (PCA), and then analyzed the measured data of three measuring points in five directions. The results showed that: 1) LAD and LAI of the northern part point under canopy were a little greater than those of southern part point under canopy and DIFNs of the two measuring points were both low, suggesting that the canopies had great shielding effect; 2) At the sun light direction at noon time, DIFN of southern part point under canopy was greatest, followed by that of the northern edge point of canopy, and the least was at the northern part point under canopy, indicating that the transmittance of direct solar radiation at the southern part was high though LAI there was great. At the summer solstice, DIFN of the northern edge point of canopy was greatest, followed by the southern part point under canopy, and the least was at the northern part point under canopy; at the vernal equinox and autumnal equinox, DIFN of the southern part point under canopy was greatest, the northern edge point of canopy was in the second place, and the least was at the northern part point under canopy; 3) The result of daily variation of direct solar radiation at the northern edge of V. negundo var. heterophylla showed that: light transmittance at east and west parts were greater, and those at southeast, south, and southwest were roughly the same; around the summer solstice, DIFN at the noon was greater than that in the morning and evening. This paper provides solar direct radiation transmittance measurement method under isolated shrubs canopy, and at the same time it provides the shielding effect at different positions under V. negundo var. heterophylla canopy and sets up scientific basis for determination of appropriate seeding position of afforestation under V. negundo var. heterophylla canopy.

The distribution pattern of biological soil crust under Artemisia ordosica in Mu Us sandy land and its driving factors were analyzed by means of line transect sampling. The results showed that there were obvious differences in the thickness of biological soil crust around A. ordosica. The maximum of the thickness was found on the northwest of the plant. The thickness on the southwest and northeast of the plant were the thinnest and showed no significant differences. The thickest of the rust, 1-10 cm on average, were about 0 -20 cm apart from the A. ordosica. The thickness of biological soil rust varied with its distance from the plant. Within 60 cm, the nearer it was from the plant, the thicker the rust was. The distributions of biological soil rust were relevant to the wind direction and the distance from A. ordosica. Affected by the wind direction, A. ordosica could help retain more dust and accelerate the development of biological soil rust on the northwest. Meanwhile,A. ordosica plants provide favorable conditions for the growth of biological soil crust.

This paper aims to study seed germination and seedling emergence of three dominant species (Caragana korshinskii Kom, Medicago sativa Linn and Elymus dahuricus Turcz) in Mu Us sandy land under different water supply regimes and sand burial depths. The results indicate that: 1) For C. korshinskii and M. sativa, a relative large number of seeds emerge mostly at 2.5 -5.0 mm water supply. The maximum seedling emergence rate of C. korshinskii is 59.00% ±7.21%, while that of M. sativa is no more than 40%. The seedling mortality of M. sativa is relatively high at 2.5 mm water supply, which means the death of a lot of seeds after germination. 2) For E. dahuricus, seeds emerge well at 5.0 -9.0 mm water supply. The maximum seedling emergence rate of E. dahuricus is 52.67% ±10.67%. 3) The most suitable sand burial depths for the seeds of C. korshinskii and M. sativa are 0.5 -1 cm and 0.5 cm. As the burial depth increases, the seedling emergence rate of two species, C. korshinskii and M. sativa, decreases significantly. C. korshinskii has the highest rate of non-emergence at 4.5 cm burial depth. 4) E. dahuricus adapts well to sand burial, and has the maximum seedling emergence rate at 4.5 cm burial depth.

In this paper,effects of litter aqueous extracts on seed germination and seedling growth of two dominant tree species were investigated in the mixed stand of Larix principis-rupprechtii and Picea wilsonii (Picea meyeri). The results were as follows. 1) Germination of two species were both inhibited by all types of aqueous extracts. The most obvious inhibition was presented by 50.0 g/ L aqueous extracts of L. principis-rupprechtii or P. wilsonii (P. meyeri). 2) Seedlings of L. principis-rupprechtii were promoted by aqueous extracts of L. principis-rupprechtii needles or Betula platyphylla barks, while they were inhibited by aqueous extracts of P. wilsonii (Picea meyeri) needles. 3) Seedlings of P. wilsonii (Picea meyeri) were inhibited by aqueous extracts of B. platyphylla barks, while they were enhanced by lower concentrations and inhibited by higher concentrations of aqueous extracts by other three litter types. 4) Biomass of L. principis-rupprechtii was improved by aqueous extracts of B. platyphylla barks at concentrations of 5.0 and 12.5 g/ L, but not at concentrations of 25.0 and 50.0 g/ L. 5) Biomass of P. wilsonii was inhibited by all types of the aqueous extracts. 6) Four types of litterfall aqueous extracts totally inhibited seeds germination and seedling growth of both species, but the effect on P. wilsonii was stronger than that on L. principis-rupprechtii.