Study On Development Of Risk Assessment Of The Reserve Resources Of Cultivated Land In Arid Oasis

Land resources to support the normal development of a strong system of socialpower, economic development, resource pressure, man and nature have becomeincreasingly prominent. Therefore, the dynamic changes of land resources has becomea key factor in the development of various economic way. At present, china′s landresources has its own natural limits: the per capita amount of arable land resources,resulting in land resources development and utilization of a direct impact on existcultivated land quality assurance and development the value of the use of arable land,it is clear, appropriate development and its important.Ecological Risk assessment is the theoretical basis for environmentaldecision-making management. Ecological Risk assessment has its own features, forexample, reting scale, risk factors and performance of complex. Complexity of therisk characterization compares with a single element risk assessment, ecological riskassessment is more comprehensive, combining the characteristics and evaluation ofthe object of the study area, research steps are summarized as follows: thedetermination of the study area, to class transfer direction, characteristics and spatialdistribution. Delta Wei-library oasis located in the Tianshan mountains, and the northof Talimu river. By the geographical impact study area for many years steamed downthe disorders, wind, and the natural disasters often have occurred, as which hasseriously hampered the sustainable development of local social and economic. In thisstudy, in1989,2001and2009remote sensing influence diagrams as a basis forinformation, and used the arcGIS professional graphics and statistics software,vectorized of the three remote sensing images, by the changes of arable land and otherincrease, analyzed the trends and cause about reasons of the reduce; Found thedirection of the conversion between the various and types by superimposing means.Selected the socio-economic data which from1999to2009, and then built the risk assessment system for the local, analyzed the time series change in risk characteristics;At last, by arcGIS and geo statistics methods to the study area was divided into smallareas to make evaluations of the risk of each region, respectively, in1989,2001and2009risk characterization space of. All the above studies showed these conclusions.(1) From1989to2009, the cultivated area is a substantial increase due toirrigation and rainfall, saline area showed an increasing trend, the increase incultivated land led to the woodland and grassland area; The development of economicleaded to the expanding of the construction land; Sandy and barren area tended todecrease, first, it was used, and the second, which was controlled; Area of wetlandsand tidal flats have continued to decline, the mainly reason is the water resources in alarge number of development and utilization, and then, the overall amount water wasreduced.(2) According to the characteristics of time series of risk, the number at risk in2001and2007up to0.54and0.67, ecological dysfunction during this period, thesystem is stable imbalance, and the overall effectiveness was declining; The minimumnumber of2009is0.49, which is belonged to a low risk state, that is untouched arableland increased, the ecosystem in a balanced and stable development stage of theproduction facilities to ensure the operation of all arable land, high productivity, highlabor productivity, to give service to the need of society and high structural integrityof the system, and the ecological environment didn't damaged nearly. Reservefarmland resource development risk is relatively low in2000and2005, respectively,0.54and0.53, that is at the same time of the arable land wan Developed and used, theecological system nearly complete, the overall function is powerful, the basicagricultural also can meet the need of the agricultural production, soil is basically freefrom pollution, and have strong self-purification, and soil have used with higherefficiency.(3) After spaced the low-risk areas are mainly located in the central agricultural area, with the guarantee of the science, technology and labor efficiency, then, thisrange gradually expend to the southeast, until the year of2009, there was anycultivated land has expended to the north of Talimu river; The medium risk area waswidely distributed, mainly in agricultural area around the grass, bare, sandy and saline,etc. as the main class, with the time and effort to develop this early distribution ofpatchy progressive fragmentation was the massive expansion of the distribution range;High risk range and higher risk range has distributed the southeast of the studyarea, and the north of Talimu River Basin, where a fragile ecological environment,sensitive, ability to resist risks, risk the lager2001, the highest risk index-5.8942.finally, according to the risk of space distribution, the statistics of the various types ofrisk characterization of the townships of three counties accounted for the area toprovide the scientific basis for risk management and decision-making.