YRCC

Abstract: The reasonable and synthetic treating suggestions and countermeasures are proposed according to the current condition, existing problems and its causes, through the measures like engineering technology, administration, institutions, policy, economic encouragement, drumbeating and education and scientific technology, etc and providing reference for the treatment and development of the ecological environment in the Ejina district.

The Ejina Region locates in Alashan League in the lower reaches of Heihe River. It is in the far west of Inner Mongolia Autonomous Region and the whole area is 114.6 thousand km². Ejina Region lies in the center of the inland and far from the sea. The climate is dry with a small precipitation and high evaporation. It is short of water resources and vegetation, but full of wind and sand. Therefore, the ecological environment in this area is extremely fragile. Ejina delta lies in the end of Heihe River. The delta area is 30.8 thousand km² surrounding by mountains and its center is a sealed basin. Heihe River goes through the area and ends in eastern and western Juyanhai lakes.

The main ecological and environmental problems in the current time in Ejina district are like reducing runoff, decay of the lake area, dropping of ground water level, worsening of water quality, degradation of the oasis vegetation and pasture land, reduction of livestock quantity, and serious desertification and sandstorms, etc.

The river Ejinahe is part of Heihe River. It is the only river in Ejina county and so the lifeline of Ejina oasis. But with the development of social economy, water consumption is increasing in upper and middle reaches, and results in reduction of water flowing into the river Ejinahe, the shrinking of the lower reaches of Heihe River, drying up of lakes and great reduction of water area.

According to analysis, the annual average runoff at the Zhengyixia hydrological station in the lower reaches decreased from 11.9 hundred million m³during 50’s to 7.62 hundred million m³during 90’s. The reduction is 4.3 hundred millions m³. The annual average runoff at the Langxinshan sattion which is 185 km far from Zhengyixia decreased from 5.46 hundred millions m³during 50’s to 4.03 hundred millions m³during 70’s and even to 3.46 hundred millions m³during 90’s. Compared with 50’s the reduction proportion is 31%. The reduction of water flowing to this area and the usage and loss along the river resulted in the drying up duration of the river Ejinahe longer and longer, the time of days increasing and the shrinking of the river channe.

Juyanhai lake is an area collecting water from the river Ejinahe. Long ago the water area of Juyanhai lake(It was called Juyanze) was 1200km². The river system changed with the reduction of water flowing to the lower reaches and two lakes occurred as eastern and western Juyanhai. And finally the eastern and western Juyanhai became dry one after another due to un-satisfaction to the strong evaporation.

In the Oasis area, ground water level, which depends on water supply from the river Ejinahe, shows a descending trend due to the decreasing of runoff. According to 1920s to 1940s’ data, the average depth to groundwater is smaller than 1m. There are many small lakes, swamps and springs along both side of the river. Water quality is higher. Ground water level began decreasing from 1950s and it dropped 2~3 m below ground surface in 1970s, 3~4 m in 1990s (some irrigating pasture land and farmland not included). Especially in the end of the river Ejinahe, groundwater level dropped 5m below ground because of the short duration of water flowing and no recharge to groundwater from the river (table 1). During the recent 10 years, 60% of 1000 wells in this area have not enough water supply capacity and 10% became dry.

years	Xihe river (m)			Donghe river (m)
years	Upper part	Middle part	Lower part	Upper part	Middle part	Lower part
1940s	0.5～1.0	0～0.5	0～1.0	1.0～1.5	0.5～1.0	0.5～1.0
1970s	1.6～3.35	1.57～2.52	3.39～4.07	1.32～2.94	1.19～3.15	3.32～4.45
1990s	2.24～3.57	3.2～4.07	5.0～7.0	3.25～3.85	1.94～3.35	4.5～5.75

The mineral content of groundwater increased a lot with less recharge and larger depth. The mineral content is normally smaller than 1 g/l where there is enough fresh water supplying. Generally, the mineral content decreases by 1 g/l or more when fresh water replenishment decreases, even to 2~3 g/ l.

The regional groundwater level dropping due to decrease of water flowing to Ejina Oasis results in changes from natural condition to desertification condition in this area.

According to investigations, the area ofdiversiform-leaved poplar, narrow-leaved oleaster and Chinese tamarisk osieryalong the river decreased by 573km²from 1958 to 1980,yearly reduction is 25. 9km². The reduction rate becomes larger since 1980. Up to 1994, the area of diversiform-leaved poplar, narrow-leaved oleaster, Chinese tamarisk and shrub forest decreased by 1924km², that the coverage rate is larger than 70%, and the yearly reduction is 137. 4km². In the lake basin, the area of Sacsaoul forest, which space is 2 to 3m, decreased by 58%, while the worse forest spacing by more than 8m increased 89%. The area of arbor and shrub forest showing bad appearance accounts for more than 60%. It is possible that the remaining bad forest will disappear if water supplying decrease further.

1.4 Serious deterioration of pasture land and the decrease of livestock carrying capacity

The deterioration of pasture mainly exhibits in the reduction of grass production, change of species and the quality getting worse, etc. The vegetation species, density, coverage and yield go down sharply with the continuously decreasing of water. The area of wood, cluster and meadow which coverage is larger than 70% decreased 78.26%, while the area of Gobi and desert which coverage is smaller than 30% increased 67.63%.

The decreasing rate of the upper grass is enormous and nearly 17.33 km². The herb species have decreased from 200 species in 1950s to 80 in the current time. Originally there are about 130 edible meadows and now only 20 exist alone with miscellaneous and poison grass. And accordingly the grass yield has decreased from 225～300 kg/ hm² during 1950s to 150 kg/ hm² during 1990s and the carrying capacity decreased from 0.5 sheep unit/ hm² to 0.27 sheep unit/ hm².

The desertification is becoming more serious due to the deterioration of vegetation and the shrinking of the Oasis and the influence of bad local climate. According to the image data in 1960s and 1980s, the Gobi and the desert area increased by 462 km², the annual increase was 23.1 km². Among the whole area 70.7 thousand km², the desert area increased from 25.8 thousand km² in the middle of 1980s to 34 thousand km² in the year 2000. All this shows a trend of increasing area of desert and the Oasis is being eroded gradually.

The climate in Ejina region is extremely dry. Sandstorm weather always appears in spring and winter.

According to statistics, there are 29 days with the yearly average strong wind(strong wind means the instantaneous velocity is larger than 17m/s, equivalent to 8th grade wind ). The number of sandstorm days is up to above 20 days and even 46 days. In recent years, the frequency of sandstorm is getting higher and higher, the intensity stronger and stronger. Its influence involves north and northwest of china and even eastern part of china. The total influenced area is about 2000 thousand km². Sandstorms occurred in the year 2000 made an alarm to human being that " the sandstorm arises from Ejina ".

The reasons of regional ecological environment deterioration are very complex. Generally speaking, there are two main aspects: the first is human factor such as the increase of population and livestock, soil and water development, destroying and cutting forest by human being and excessively pasturing, etc. The second is a natural factor like the changes of climate, hydrology, geology and geomorphology. Both of this two factors resulted in the regional deterioration of ecological environment.

With the development of industry and agriculture and the increase of population in the whole basin, the extensive development and utilization to soil and water resources began. The water flowing to the lower reaches decreased and caused the reduction of lake area and thus the dropping of groundwater level, etc. The changes of hydrology conditions directly lead to the drought, the underground changes of vegetation, the deterioration of vegetation growing environment. The vegetation landscape is changing into desert view. It is obvious that the shortage of water resources and shortage of suitable moisture for vegetation growth are the main reasons for the regional ecological environment deterioration in Ejina area. At the same time, the increase of population, the development of agriculture and pasture, bad management, unreasonable cultivation and excessive pasturing all the factors advanced the deterioration of environment. Therefore, the ecological environment deterioration is mainly the result of human activities and the natural factors accelerated the changes.

3. Countermeasures and suggestions for comprehensive treatment to the ecological environment of Ejina Oasis

The key method are selecting suitable irrigation ways, reasonable layout of canal system and optimizing water resources to ensure the necessary moisture for vegetation growing and thus to restore the Oasis ecological environment. All of this should take into account the local character and suitable moisture for vegetation growth, the treating targets and stresses, soil moisture and geomorphology, etc.

Firstly, the scientific layout of key projects, building control projects and Donghe canal and its sub-canal are the primary tasks regarding increasing water transportation efficiency, reasonable allocating water from Langxinshan and enlarging its area.

Secondly, the suitable irrigation method should be selected according to different local natural geography and topography, growth characters of local vegetation and its moisture condition needed and local water resources. The main measures are like abstracting groundwater mainly in upper reaches of the river Xihe and Donghe, matching with small borden irrigation, ditch irrigation and pipe irrigation. For the purpose of recharging groundwater in the lower reaches of Donghe and Xihe, some measures should be taken and the ditch irrigation is the main way in this area.

3.2 Bioengineering technology to the protection of natural forest and grass

Fencing, building artificial pasture land, diverting water for irrigation, etc. all these measures are the effective ways to protect the natural ecological environment. The reasonable technologies for environment protecting in Ejina area are as follows: fencing, determining suitable carrying capacity, irrigating properly and strengthening foster, etc. The natural vegetation area should be subdivided into 4 parts: the diversiform-leaved poplar forest protection zone along both banks, narrow-leaved oleaster forest protection zone along both banks, Sacsaoul forest protection zone and desert grassland zone. The detailed measures should be provided according the characteristics of each zone respectively.

The non-structure technologies for ecological environment restoration are the managing measures including administrative management, economic encouragement, policy guiding and institutional restriction, etc.

3.3.1 Setting up sustainable soil and water development plan guided by the general basin program

In Ejina ecological environment worsen, the most major reason is the resource of water and soil of developing and using not reasonable result. So, according to the problem of ecological environment of Ejina delta region, we should be guidance with valley program on the foundation of valley program, insist strategy of sustainable development, adopt to basis water quantity regard as action standard, decide scale and development with water quantity, develop and protect are equal important, near future and long-term combination, the principle of the coordinative development of economic society and ecological environment, scientifical establish the development and using program about regional resource of water and soil, strengthen management and the adjusting control of the delta resource of water and soil, in process of using the resource of water and soil, far and near combination, according to local conditions, reasonable use, coordinative the contradiction between development of animal husbandry and renovation of grass degeneration, realize the harmonious unification between society, economy, resource and environment.

3.3.2 Reinforcing organizations and leadership and making clear the responsibilities for ecological production

Protect and renovate the ecological environment and develop and use efficiently the resource of water and soil, is a systematic project of concerned with numerous department. It is need mind and participation of whole society. So, we must have powerful organization guarantee, definite every department responsibility, reinforce lead and unify coordination. We must strengthen organization lead, perfect system of job responsibility, and insist on that the ecological construction is a long-term strategic task and place it into important agenda. We must reinforce leading management system, implement ecological renovation protect responsibility.

It is the result of artificial campaign that Ejina region ecological environment worsen, thus must establish develop policy of person and nature harmonious coexist, the population policy of proper enforcement, control the excessive increase of person and domestic animal in Ejina region, it is meanings that must strictly control the quantity of domestic animals, herd surely with water, decide domestic animal with grass, carry out reasonable rotatable grazing; carry out ecological immigration policy, thorough solute the pressure of fragile ecological environment because of population, domestic animals, reduce the hurt because of pressure come from person and domestic animals in Ejina oasis ; perfect policy of natural forest surrounded, enlarge surrounded scope, economic encouragement to fencing, and solve conscientiously surround the material problem of forage grass of herdsman’s domestic animals, at the same time should still establish corresponding manage and protect method, strengthen surround effect, make fencing work insist for a long time.

First, will implement transfer develop strategy: That implement transfer develop strategy is want to make whole county scatter highly farmer and herdsman transfer to the regions where natural environment and social environmental are better, using these region’s better infrastructure conditions concentrate carry out development and construction. According to whole county existing natural environment and economic social foundation, on the basis of economic geography partition, we may be concentrate transfer step by step to " a town 4 districts " include the farmer and herdsman and the first, second and third estates of whole county. 6 villages,1 town and 1 livestock farm whole county existing will be adjust is : Dalaihubu town is center, in east build Bayantaolai ecological farming and stockbreeding areas, in west build Sanhantaolai industrial develop zone, in south build Bayanbaogede characteristic farming herd merchandise district, in north build Ceke port border trade special develop zone, develop intensify economy. In other regions carrying out surround grass, forbid herd, rotatable grazing, restore the ecological environment of serious degeneration.

Secondly, will implement " ecological economy " type industrial structural adjustment: According to the condition of ecological environment and the actual social economy of Ejian county, present major restrict factor is oasis ecological environment worsen. In the future must depend on the improvement of oasis ecological environment. It is guidance mainly with that " focal point is gets vigour travel economy, promotes port trade vigorously, develops steadily desert oasis economy ". Urge that local economy development turn to ecological type economy, this is helpful for oasis ecological environment protect and improve step by step.

3.3.5 Establishing economic encouragement mechanism suitable to ecological treatment

For promoting the Ejina region ecological renovation and remediation, giving some economical encourages to surrounding the grazing to keep grass breeding and reforest in formerly cultivated land. Notice the forestry can be used by animal husbandry at the same time, looking after to herdsman's realistic benefits, ensure enlarge herdsman 's income. Nation and government must give the support to farmer and herdsman on the funds, real object, manpower, technique for they abandon Cultivate and graze, guaranteeing their income level not lower than former, making people get to the real benefit that they abandon Cultivate and graze. Establish the diversified investment mechanism, open investment channel widely, establish the diversified, multi-level and multi-channel,, flexible and various investment system, provide the economy guarantees for promoting the ecological renovation and remediation.

The protection and administration of the ecological environment are besides needing support of economic, technological measure, needind strong guarantee of relevant laws and regulations, rules and regulations at the same time. Should follow country's relevant laws and regulations, the demands of management rule and relevant laws of ecological environmental protection, etc., make the corresponding regulatory files or relevant rules, establish and improve system of various kinds of rules, offer the legal guarantee for renovation of the ecological environment in the area.

First, should strengthen regional water yield allocating and management: Still lack the perfect allocated and utilizing scheme of water yield arrived in the Langxin mountain form Heihe River at present, with the goal of adjust water three years is realized ahead of time, water yield allocate issue is appear even in lower breaches of Heihe River, necessary to make one perfect reasonable water yield allocated scheme.

In addition, should strengthen allocating and management of arrived water form Heihe River. According to Ejina oasis distribute with all area and requirement of water in every area, disposed arrived water reasonable from space-time, combine different regional groundwater resources state, jointly allocate the surface water and groundwater. To supervise and inspect to the water yield allocated and utilized course, perfect the monitor network in area, improve monitoring means, improve the quality of monitoring.

Ecological environment improvement is a long-term arduous task of a social benefit type, must arouse the ecological protection consciousness of the whole society. In order to guarantee the ecological construction project can be launched smoothly in an all-round way, should strengthen propaganda strength, fully utilize such many kinds of propaganda medias as the broadcast, TV, newspaper, information, etc., propagate the importance and necessity of ecological construction extensively, improve the ecological protection consciousness of peasants and herdsmen.

In order to solve fundamentally the problem of ecological environment worsens, the related departments should strengthen the work of basic research to ecological environmental protection, strengthen the fund input power about study, organize many departments and multi-disciplinarily jointly tackle key problems,, demonstrate and popularize through key research and specially test, solve the problem that the regional ecology degradates and substantivly fundamentally, realize the benign cycle of ecological function in Ejina, reach the harmony and unify with the population, resource, environment, social, for offer feasible scientific basis and technical support to rescue and resume life in the past in Ejina oasis.