Changes of local agricultural landscape patterns induced by land consolidation in hilly and mountainous Southwestern China

Land consolidation (LC), as a type of human disturbance, improves land production efficiency and changes landscape distribution through land parcel reallocation. The objective of this study was to comparatively analyze the changes of landscape patches before and after a land consolidation project (LCP) and the effects of land levelling, irrigation and drainage work and road engineering on the landscape structure. FRAGSTAT3.3 and buffer zone analysis were used to investigate those changes. The results suggest that the heterogeneity of landscape depressed, and tended to simplification after LC. Dry land was the most highly variable land use pattern, and the change of forestland was least due to its locations at a gradient larger than 25°. LC resulted in a more rational use of land, and could be an important step in promoting rural development in depressed and fragmented agricultural areas through unused land exploitation, small-patch combination, irrigation and water conservancy, and road construction. Land levelling leveled off the gradient field surface and decreased the slope. The fragmentized patches were much more incorporated with increasing slope. On the other hand, the ridge of a field became longer so that the length of field surface and area of patch were increased. Land levelling regulated, simplified and combined patches, so that the complexity degree was reduced. It is found that the buffer distance of 35 m was a turning point of human disturbance by irrigation and drainage systems, and patches presented flaky distribution when the buffer distance was smaller than 35 m. Meanwhile, the distance range between 25 m to 50 m was an impressible area for road engineering, which was sensitive to human actions, and the changes of all landscape metrics were larger than those in other buffer zones. In general, LC not only reallocated fragmented parcels, but also improved agricultural conditions.

[1]  Gopal B. Thapa,et al.  Alternative options of land consolidation in the mountains of Nepal: an analysis based on stakeholders' opinions , 2008 .

[2]  Xuezheng Shi,et al.  Relationship between soil erosion and distance to roadways in undeveloped areas of China , 2008 .

[3]  A. Coffin.  From roadkill to road ecology : a review of the ecological effects of roads , 2007 .

[4]  Cui Bao-shan.  Ecological effects of different road classes on landscape in the Lancang River valley , 2007 .

[5]  John N. DiBari,et al.  Evaluation of five landscape-level metrics for measuring the effects of urbanization on landscape structure: the case of Tucson, Arizona, USA , 2007 .

[6]  Petr Sklenicka,et al.  APPLYING EVALUATION CRITERIA FOR THE LAND CONSOLIDATION EFFECT TO THREE CONTRASTING STUDY AREAS IN THE CZECH REPUBLIC , 2006 .

[7]  Per Løfstrøm,et al.  Economic and environmental analysis of buffer zones as an instrument to reduce ammonia loads to nature areas , 2006 .

[8]  Nobukazu Nakagoshi,et al.  Changes in landscape spatial pattern in the highly developing state of Selangor, peninsular Malaysia , 2006 .

[9]  R. B. Hammer,et al.  Road development, housing growth, and landscape fragmentation in northern Wisconsin: 1937-1999. , 2006, Ecological applications : a publication of the Ecological Society of America.

[10]  E. Clercq,et al.  A method for the selection of relevant pattern indices for monitoring of spatial forest cover pattern at a regional scale , 2006 .

[11]  Hubert Gulinck,et al.  Evaluating change in agricultural landscape pattern between 1980 and 2000 in the Loess hilly region of Ansai County, China , 2006 .

[12]  Volker C. Radeloff,et al.  Road Density and Landscape Pattern in Relation to Housing Density, and Ownership, Land Cover, and Soils , 2005, Landscape Ecology.

[13]  J. Nassauer,et al.  Limitations of using landscape pattern indices to evaluate the ecological consequences of alternative plans and designs , 2005 .

[14]  P. Spooner.  Response of Acacia species to disturbance by roadworks in roadside environments in southern New South Wales, Australia , 2005 .

[15]  Claire C. Vos,et al.  Evaluating the effect of corridors and landscape heterogeneity on dispersal probability: a comparison of three spatially explicit modelling approaches , 2005 .

[16]  D. Fox,et al.  Limiting sediment deposition on roadways: topographic controls on vulnerable roads and cost analysis of planting grass buffer strips , 2004 .

[17]  C. J. Álvarez,et al.  Economic, social and environmental impact ofland consolidation in Galicia , 2002 .

[18]  G. Willems,et al.  Reducing habitat fragmentation by minor rural roads through traffic calming , 2002 .

[19]  Rob H. G. Jongman,et al.  Homogenisation and fragmentation of the European landscape: ecological consequences and solutions , 2002 .

[20]  Sari C. Saunders,et al.  Effects of roads on landscape structure within nested ecological units of the Northern Great Lakes Region, USA , 2002 .

[21]  L. Tischendorf.  Can landscape indices predict ecological processes consistently? , 2001, Landscape Ecology.

[22]  Wenjun Li,et al.  Designing the buffer zone of a nature reserve: a case study in Yancheng Biosphere Reserve, China , 1999 .

[23]  W. Baker,et al.  Contribution of Roads to Forest Fragmentation in the Rocky Mountains , 1996 .

[24]  Q. Lu.  A review on the ecological and environmental impacts of agricultural ditch systems in wetlands , 2007 .

[25]  C. J. Álvarez,et al.  Evaluation of productive rural land patterns with joint regard to the size, shape and dispersion of plots , 2007 .

[26]  Murat Demir,et al.  Impacts, management and functional planning criterion of forest road network system in Turkey , 2007 .

[27]  W. Baker,et al.  Watershed analysis of forest fragmentation by clearcuts and roads in a Wyoming forest , 2004, Landscape Ecology.

[28]  Cao Zhi-Qiang.  Analysis on the Patch,Corridor and Fragmentation of Nature Reserve in Anshan , 2003 .