| Wetland is an important ecological system. The unique function of wetland hassignificant ecological, social, and economic values, which cannot be substituted. A largeexpanse of wetlands have disappeared in the past years and regressed as humanactivities increased. This situation has created serious ecological and social problemsand even threatened the sustainable growth of regions, nations, and the world.Combined with technology, the study explored wetland spatial optimization to recoverthe functions of wetland, which has great significance in the improvement of wetlandecological conditions, full exhibition of wetland functional features, and sustainablegrowth of ecological environment.The Sanjiang Plain is located in the northeast of China and is the largest naturalwetland region in the country. The Sanjiang Plain experienced three phases ofcultivation since the founding of new China because of the continuous demand for grainproduction, which led to the rapid decrease in the natural wetland area and the rapidgrowth of cultivated farmlands. The worsening conditions of the regional environmenthave seriously harmed the wetland ecological system. The Sanjiang Plain is the researchfocus of this study. Data sources used to optimize the wetland space for the SanjiangPlain based on the GIS spatial analytical technology according to the principle ofmulti-objective ant colony algorithm include images from Landsat TM, land utilization,and weather data. First, a systematic analysis and assessment of the majorcharacteristics of the Sanjiang Plain (runoff adjustment function and suitability functionfor wild animal habitats) was conducted. Second, Matlab was employed as thesecondary development platform to construct the optimization system of the originalwetland space for the Sanjiang Plain. An optimization model for multi-objective ant colony algorithm was created based on GIS technology under the guidance ofmulti-objective optimization theory by combining the current spatial optimizationconfiguration algorithm. By optimizing the regional wetland ecology, the system andfunctions as the objective, and under the limitation of balanced development of wetlandand agricultural production, we conducted the spatial optimization analysis of thewetland ecological system in various wetland regions of the Sanjiang Plain. Finally, weconducted a comprehensive assessment of the optimization effect from the viewpoint ofobjective coefficients, the overall wetland landscape configuration, and the balanceddevelopment level of wetland and agricultural production. We provide the followingconclusions.(1) From the analysis of the hydrological regulation function in the Sanjiang Plain,we found that the runoff regulation of the Sanjiang Plain in2010was between187mmand570mm, and the total hydrological regulation was4.42×1010mm. The quantity ofwetland hydrological regulation was4.64×109mm, comprising10.49%of the totalhydrological regulation. In general, the runoff regulation capacity in the Sanjiang Plainhas strong spatial differentiation because of its high evapo-transpiration features, suchas large bodies of water and wetland marsh.(2) The Sanjiang Plain is most suitable for waterfowl habitats, and the suitablehabitats measure1.19×106ha and2.09×106ha, comprising30.27%of the total area ofthe plain. These areas are mainly distributed in lakes and rivers. The decrease in suitableareas for waterfowl habitats in those regions are related with the increase in humanactivities. To resolve the conflict between human economic development and ecologicalsafty, strengthening the multiple biological protections is necessary to maintain thestability in the regional ecological system.(3) The efficiency of cultivated land in the counties (cities) of the Sanjiang Plainhas significant spatial differentiation. The counties (cities) with the highest efficiency incultivated land (efficiency value of cultivated land>0.75) are located in the plain areasin the northeast of the Sanjiang Plain (Fuyuan, Tongjiang, Fujin, and Raohe) andMuling and Xingkai Plains in the south of the Sanjiang Plain (Hulin and Baoqing). The number of counties (cities) with efficiency value of wetland>0.75was quite small,which included Fujin, Baoqing and Jiamusi. From the efficiency values of wetland andcultivated land, the five counties of Baoqing, Youyi, Fujin, Tongjiang, and Hulin havebetter balanced development (development level value>0.75), indicating that thebalanced development of agricultural production and natural wetland in the SanjiangWetland has significant spatial differentiation.(4) To employ Matlab as the platform to construct the spatial optimization systemfor the Sanjiang Plain, three groups of coefficients were selected to achieve the wetlandspatial optimization. The analytical results showed that the wetland areas under thethree circumstances have increased compared with the2010. After optimization, theareas of wetlands were8.24x105ha,15.09x105ha, and10.21x105ha. Comparedwith2010, the wetland distribution increased by22.62%,124.55%, and51.93%. Thearea in Group1had the least increase, which was related to its partial limitation. Thearea in Group2has the highest increase, which was more than twice of the wetland areain2010. The increase was attributed to the slow limitation of its set coefficientalgorithm. From the objective view, Groups1and2were not the best optimizations.Group3achieved the overall optimization under the circumstance of coefficientsestablished for the last two groups. The group has achieved timely limitation, which wasthe ideal for wetland optimization effect.(5) The analytical results of the overall wetland landscape configuration, objectivecoefficients, and the balanced development of wetland and agricultural production andtheir effects on wetland spatial optimization and overall landscape analysis indicate thatthe number of wetland patches has decreased. By contrast, the average patch density,concentration coefficient, and landscape variety have increased, which implies that thelandscape configuration starts to benefit the wetland ecological functions and has greatsignificance in maintaining the regional ecological safety. The effect of wetlandoptimization was achieved, and the ecological environment was improved. Thehydrological adjustment objective analysis showed that the wetland spatial optimizationresulted in the63%increase in runoff in the regions of the Sanjiang Plain. Compared with the pre and post-optimizations of wetland space, the total runoff regulation of theSanjiang Plain has increased by10.08%from28.57×109m3to31.69×109m3. Theobjective analysis of suitability of the plain for waterfowl habitats showed that after thewetland spatial optimization, area was most suitable for waterfowl habitats. Goodsuitability increased from1.19106ha and2.09106ha before the optimization to1.92106ha and2.38106ha after optimization, with a net increase of0.73×106ha and0.29106ha, respectively. Agricultural production decreased from0.875before theoptimization to0.804after the optimization because of the wetland spatial optimization.The wetland benefit has increased from0.769before the optimization to0.873after theoptimization. The balanced development level has achieved significant growth that hasreached0.824because of the wetland spatial optimization. The results indicated that theimplementation of wetland spatial optimization according to the optimization results inthis paper will significantly improve the balanced development level of agriculturalproduction and wetland marshes in the Sanjiang Plain. |
PDF Full Text Request