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Shelterbeltsystem in pasture ofsandyland

It is meaningful in combating desertification to develop shelterbelt in pasture with annual precipitation of 350-400 mm. tte main shelterbelt should be vertical to dominant wind direction and accessory shelterbelt is orthogonal with main shelterbelt. tte density of forest network has a direct effects benefit on combating wind sands.

Shelterbelt for railway in sandy land areas

Building shelterbelt for railway in desertification and semi-desertification is the most difficult projection. Shapotou railway Shelterbelt in Ningxia of China is a successful example of combating desertification (discussed details bellow).

Typical models in combating desertification in China

Typical models for combating desertification in oasis ofarid areas- Shelterbeltsystem in oasis in Hetian, XinJiangAutonomous Regions

18.6.3.1.1 Natural conditions

Hetian county is located north of the Kunlun Mountain, southwest of the Takli-makan Desert with an annual precipitation of 34.8 mm and an annual evaporation of 2564 mm. tte Taklimakan Desert is approaching Hetian county at a speed of 3-5 m per year.

Strategies for combating desertification

Sands enclosure, protecting and constructing shelterbelt were implemented by making use of local fine water condition. By selecting appropriate economic trees and fruits trees, an ecological -economic shelterbelt was build up.

Practical countermeasures

Sands enclosure: To protect and restore natural desert vegetation such as Populus enphratica forest and Tamarix ramosissima so as to maintain and expand oasis.

Shelterbelt system in oasis: To build shelterbelt system with tree-shrub-grass and multi-trees varieties in the edge of oasis and desert, tte length of main forest belt is 600 km while a desert vegetation protection belt with 10-15 km built outside main forest belt.

Cropland shelterbelt network: To build a cropland shelterbelt network with narrow forest belt and small network in oasis, such as economic trees or grape aisle.

Typical model for combating desertification for railway in arid areas - Shapotou, Ningxia railway sands stabilization

18.6.3.2.1 Natural conditions

Shapotou District, Zhongning Couty, Ningxia is located in south-east of Tengger Desert and bordered upon irrigated Plain in Zhongwei. ttere are lots of high shifting dunes threatening the Bao-lan railway. Mean annual precipitation is 186.2 mm with ground water at 80 m. tte vegetation fraction is less than 1%.

Strategies for combating desertification

In order to prevent the middle segment of Bao-lan railway from the invasion of forwarding sand dunes, a forefront stopping sands belt along with railway was built.

Practical countermeasures tte shelterbelt system consists of five belts outward of the railway with the length 300 meters of windward and 200 meters of leeward and a straw barrier belt is the core part.

Sands stabilization and fireproof belt: Stones, loess or slag are laid along with railway roadbed, 20 m windward and 10 m leeward.

Afforestation belt with irrigation: tte aim is to reclaim terraces for farming and build irrigation channel for afforestation in the scope of 60 m of windward outside of the first belt and 40 m of leeward outside, tte trees are planted mixed with shrub.

Straw barrier belt: In the scope of 240 m of windward outside and 160 m of leeward outside, straw check-board barriers of lm x lm are set up to stabilize sands in autumn, then shrub seeds are planted in the center in the season with more rainfall and application of irrigation. With the benefits of vegetation shelterbelt in a long time the soil macrobiotic crust gradually formed on the sands surface and become thick, which adjusted soil water and nutrition, and consequently with some vegetation survival (Bai et al. 2003; Long and Li 2003).

Forefront stopping sands belt: tte vertical sand barriers made from wattle are set up at the top of dunes, and the barriers with height of 1 m are buried 30 cm underground.

Sands enclosure belt: tte windward slope of dunes in forefront stopping sands belt, is enclosed with sand barriers and planting shrubs so as to promote growth and reproduction of natural vegetation.

tte combating techniques in Shapotou received an award of special prize in Science and Technology in China, and also by UNEP and UNDP.

Typical model for combating desertification in farm-pastoral transition zone in semi-arid region

Model 1: Integrated measures in sand area in Yulin county Shaanxi Province

18.6.3.3.1.1 Natural conditions tte Yulin Sand Area (Shaanxi Province) is located in south of Ordos Plateau, south-east of Mu Us Sand Land, tte annual precipitation is 316-450 mm and annual evaporation is 2092-2506 mm, with a mean annual wind speed of 2.0-2.5 m/s. tte high wind days total is 14-33 on the average, with maximum of 77 days, tte annual dust days totaled 81 with dust storm days ofll.5 per year.

Strategies ofcombating desertification

Firstly the shifting sandy land is stabilized and followed by adjusting the structure and ways ofland use.

Practical countermeasures

To build shelterbelt system with different structures: tte shelterbelt systems with different structures are built according to topography, water resources and features of sandy plants.

To develop integrated exploitation models: Agricultural production is developed giving priority to farm land with irrigation. Integrated models with agro-forest system are carried out including fruits trees, medicinal materials, economic crops, trees nursery, and animal husbandry.

Model2: Converting cropland to forestshrub land in the north of Yinshan Mountain in InnerMongolia

18.6.3.3.2.1 Natural conditions

It is located in the north Yinshan Mountain of Inner Mongolia with an annual precipitation of 220-350 mm, most of which was received during July to September. Average wind speed is 4-6 m/s and there are 50-80 days with wind force scale beyond 8.

Strategies ofcombating desertification tte converting cropland to forest and shrub is mostly emphasized.

Practical countermeasures

Bio-measures are given priority: tte wide shelterbelt is modified to narrow shel-terbelt. Shrubs are dominant with tree-shrub-grass combination.

Hills as unit for rehabilitation: tte top of upland hills with severe wind erosion and sloping cropping field with gradient greater than 15° are converted to grass and shrubs. Sloping cropping fields along with slope at the middle and bottom of the hills are changed as contour ploughing so as to control water erosion, tte bottomland is improved as cropland with high productivity.

Model3: Integrated ecological-economic exploitation in familycourtyardin Wongniutecounty inlnnerMongolia

18.6.3.3.3.1 Natural conditions

Wongniute county is located in middle of Chifeng city in Inner Mongolia, west of Horqin Sandy land with a mean annual precipitation of 340 mm, mean annual evaporation of 2233.7 mm, and an average annual wind speed of 4m/s and 73.9 days of wind force scale beyond 8.

Strategies ofcombating desertification

An integrated exploitation model in family courtyard was adopted. It consists of utilizing solar energy, developing biogas, growing vegetables in plastic green house and feeding pigs in heating shed.

Practical countermeasures tte key technique is to transform solar energy to heat in green houses and shed for vegetable, grape tree and animal husbandry in winter, and also to use biogas produced from dejecta of pigs to heat and fuel for family.

Model 4: Combating desertification and sandification in Naiman county oflnnerMongolia

18.6.3.3.4.1 Natural conditions

It is located in central of Horqin sand land interlaced by dunes and interdunes. tte desertified soil acreage increased from 20% in 1950s to 77.6 % in beginning of 1990s.

Strategies ofcombating desertification tte basic principle is to modify current land use status with unitary agriculture, to implement the sand enclosure, and set up plant barriers to stabilize sands in the surface of dunes.

18.6.3.3.4.3 Practical measures

In undulating sandy lands, converting farmland to forest/shrubbery is given a priority, and shelterbelt forest network is set up. As for the sand encroached area with interdunes, different countermeasures are taken according to local natural conditions.

Typical model for combating desertification in steppe in semi-arid region -Fenced grassland development in Erdos oflnnerMongolia

18.6.3.4.1 Natural conditions

In Erdos, the mean annual precipitation is 266-412 mm, with an average annual wind speed of 3.5 m/s, and sand storm days totalling 11-24.

Strategies ofcombating desertification

"Ku lun" refers to fenced grassland in Mongolia language. It is the basis of pasture development, and its establishment is focused on "water, grass, forest, feed, and machine."

Operational countermeasures tte combination of tree-shrub-grass is adopted to control sand damage, tte objective is to promote integrated development with agriculture-forestry-animal husbandry.

18.7

Services for combating desertification in Chinese Meteorological Offices

Research on desertification development and combating in terms of meteorological conditions

A large number of observations and research on the development and causes of desertification as well as climatic effects of combating desertification measures were carried out in China Meteorological Administration (Lu et al. 2006; Bai et al. 2006;

Fig. 18.4. Changes in average annual temperature and precipitation Apr. to Sep.

Li and Lu 2002; Zhou et al. 2002). A case study on causes of desertification in Xi-linguole Steppe made by Xilinhaote Institute of Animal Husbandry-Meteorology is demonstrated in paper.

Effects ofclimate change on desertification in Xilinguole Steppe

Figure 18.4 shows the smoothing average of annual temperature and precipitation in Apr.-Sep. in meadow steppe, typical steppe and desert steppe. It is clear taht the temperature increases and precipitation falls during growing period of pasturage.

According to calculations, the decrease of every 1 mm precipitation would reduce grass yield by 100-200 kg/ha. So drought results in sand encroachment and degradation.

Effects ofman-made interference on wind erosion and soil degradation in Xilinguole Steppe tte effects of man-made interference on capacity of anti-wind erosion in typical steppe was carried out by means of wind tunnel and taking soil under original status (Xu et al. 2005). Several man-made interferences includes free grazing, fenced grassland in 1987 and 2003, and cropland, tte results indicate that when the wind speed is lower than 12 m/s the wind erosion increases slowly, while it rapidly increases at wind speed of 12-16 m/s. It also can be seen that at any wind speed the wind erosion rate in free grazing land is higher than fenced grassland, and wind erosion rate in earlier fenced grassland (1987) is lower (Fig. 18.5). It is proved that fencing is an effective measure to control degradation of typical steppe.

Fig. 18.5. Wind erosion rate under different wind speed in different steppes. (Source Yu et al.)

Effects ofman-made interference on biomass inXilinguole Steppe

^e biomass above the ground was measured in free grazing land, fenced grassland (in 1987, 1997, and 2003) and cropland respectively in April, July, August and October, ^e results show that the order of biomass value is: fenced grassland in 1987> fenced grassland in 1997> fenced grassland in 2003>free grazing>cropland. It indicates that reclaimation and grazing might reduce the biomass of ecosystem, while fencing is in favor of increasing biomass.

Monitoring and assessing services to combating desertification ofgrassland

Estimation ofcarrying capacityin animals in grassland

In Xilinhaote Steppe feed of animals is mainly from reaped hay in autumn and remainder on grassland in winter, therefore the carrying capacity for animals in cold season depends on growth status of natural grass and snow recovery on grassland in winter. A model to calculate carrying capacity for animals in cold season was developed (Yang et al. 2001) as follows:

^e rational carrying capacity for animals in cold season in 1996 and 1997 were calculated and compared with actual values (Table 18.1). It can be seen there are imbalances in carrying capacity with excess or shortage, ^is information is useful for local government to rationally use resources in grassland and alleviate desertification.

Table 18.1. Comparison between rational and actual carrying capacity for animals in cool season 2

in Xilinguole (sheep unit/km )

Table 18.1. Comparison between rational and actual carrying capacity for animals in cool season 2

in Xilinguole (sheep unit/km )

steppe Type

Harvest year

Rational values

Actual values

Excess -) shortage (+) %

1996

1997

1996

1997

1996

1997

1996

1997

desert

bumper

poor

42

28

50

61

-19

-118

typical

bumper

bumper

72

50

107

83

-49

-66

meadow

bumper

bumper

154

113

76

101

+51

+ 11

Source: Yang et al.

Source: Yang et al.

Monitoring and forecasting system ofanimal husbandry in steppe

In order to provide meteorological information services for farmers and government a monitoring and forecasting system of animal husbandry for northern steppes in China was established (Wei et al. 2005). tte system includes 5 sub-models: data base, climatic monitoring and diagnosing sub-model, forecasting submodel and decision-making as well as service sub-model. In climatic monitoring and diagnosing sub-model the effects of climate conditions on growth, development and yield formation of grass are assessed, tte forecasting sub-model includes functions of predicting date of green grass return and date of enough grass for animals, prediction of grass output, death rate of animals in spring and carrying capacity for animals in cold season.

Meteorological information services to animal husbandry ofsteppe tte animal husbandry-meteorology station and forest- meteorology station in the agrometeorological station network in China Meterological Administration (CMA) play a role in combating desertification and restoring ecosystem. For example, the Xilinhaote Institute of Animal Husbandry-Meteorology provides the information services of monitoring and forecasting of animal husbandry and consultation services in ecosystem restoration and combating desertification. Various bulletins are reported for the government and the department of ecosystem protecting and combating desertification, which include climate review, effects of climate on ecological environment, outlook of climate-environment, and suggestions on ecosystem protecting and combating desertification, tte forecasting of date of green grass return and date of enough grass for animals is adopted by government as the basis for determining beginning and ending dates of seasonal sand enclosure, and the estimation of carrying capacity for animals in cold season is used to determine proper number of full-grown animals.

Monitoring and predicting of dust storms in China tte occurrence and development of dust storm are related to ecosystem and general circulation, so the monitoring and predicting of dust storm is not only a part of preventing from dust storm, but also a service task of NMHSs to combating desertification. CMA set up monitoring network of sand storm in China, and developed numerical forecast system of sand storm.

tte sand storm monitoring network in China includes:

Observation network ofCMA

It consists of 2456 meteorological observation stations. Apart from conventional observation data in CMA, some data of adjacent countries is made available by WMO data exchange are used in dust storm monitoring.

Sandstorm monitoring networkin CMA

ttere are 24 observation stations located in the areas suffered by sand storms in northern region of China, important data such as PM10 (particle matter with diameter less than 10 ^m), visibility measured by instruments and dust fallout are obtained in real time.

Sandstorm monitoring networkin China Environment ProtectAdministration ttere are 45 observation stations located in the 11 provinces in northern region of China. PM10 and TSP (total suspended particle) are measured.

Monitoring using meteorological satellite tte data from meteorological satellite -China Fengyun 2C are retrieved to obtain information on the distribution and extension of east Asia sand storms.

Present operational services ofMonitoring and numerical predicting ofduststorms in China

China duststorm website and information services

China dust storm website (http://www.duststorm.com.cn) issues monitoring and forecasting information on dust storms provides knowledge and research progress in dust storm to public, tte contents of website are dust storm monitoring, dust storm forecast, dust storm assessment, dust storm yearbook, yearbook knowledge as well as dust storm research results.

Numerical forecasting ofduststorms

Center for Atmosphere Watch and Services (CAWAS) in CMA developed an advanced numerical forecast system of dust storms, which describe the concentration distribution of sand dust in Asia, and has been put into operation in CMA. It predicted well the dust storm weather process in 2004, 2005 and 2006. tte numerical forecast information is issued on the official website of CMA (http://www.cma.gov. cn) and website ofWWRP, International Sand storm Research Programme.

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Getting Started With Solar

Do we really want the one thing that gives us its resources unconditionally to suffer even more than it is suffering now? Nature, is a part of our being from the earliest human days. We respect Nature and it gives us its bounty, but in the recent past greedy money hungry corporations have made us all so destructive, so wasteful.

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