tailieunhanh - LANDSCAPE ECOLOGY in AGROECOSYSTEMS MANAGEMENT - CHAPTER 13

Hướng dẫn sinh thái đối với quản lý của Afforestations ở nông thôn Những biến đổi trên diện rộng của cảnh quan thiên nhiên phản ánh hàng ngàn năm của con người tác động vào hệ sinh thái tự nhiên. Đồng cỏ, các lĩnh vực trồng, trồng rừng, làng mạc, thị trấn, cụm công nghiệp, và metropolies lớn thay thế rừng, đồng cỏ và đầm lầy. Loại bỏ độ che phủ thực vật vĩnh viễn dẫn đến tăng cường nước và xói mòn gió, tỷ lệ lọc cao hơn của các hợp chất hóa học vào các hồ chứa nước ngầm. | CHAPTER 13 Ecological Guidelines for the Management of Afforestations in Rural Areas Stanislaw Balazy CONTENTS Introduction Shelterbelts and Woodlots in the Structure of Biogeochemical Barriers Principles of Mid-Field Afforestation Management Conclusions References INTRODUCTION The widespread transformations of natural landscapes reflect thousands of years of human impact on natural ecosystems. Pastures cultivated fields plantations villages towns industrial complexes and huge metropolies replaced forests grasslands and swamps. Removal of permanent plant cover resulted in intensification of water and wind erosion higher leaching rates of chemical compounds into underground and surface water reservoirs impoverishment of biological diversity and other deteriorations of the biosphere. In areas dominated by arable fields protective functions against destructive climatic effects on settlements livestock and plants were performed by the remaining afforestation fragments and bushes. Their protective role has long been recognized and appreciated and is best witnessed by the continuously supported networks of shelterbelts and hedgerows in the European countries along the Atlantic coast beginning with the western edges of Scandinavia through the British Isles down to 2002 by CRC Press LLC the northwestern parts of France Meynier 1976 Pape 1976 Stanners and Bourdeau 1995 J. P Marchand personal communication . Until now these structures were mainly composed of native plant species despite growing tendencies to introduce foreign tree and shrub species in the reafforestation of areas excluded from agricultural production Hooper 1976 Delelis-Dusollier 1986 Alexander et al. 1986 . For similar reasons the hedgerows are permanently maintained on agriculturally utilized areas in mountains and uplands of strongly diversified relief along the wide central European belt from Cantabrian to the Carpatian Mountains. In the Council of Europe paper Biber 1988 used the French term bocage for