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黃河三角洲實施“生態濕地恢復工程”

2004-04-29 00:00:00曹景華王志秀王學義
走向世界 2004年2期

進入黃河入海口的黃河三角洲自然保護區,遠遠地就看到成群連片的野鴨撲棱棱地從草叢中、水面上飛起,如傘如蓋翻飛于湛藍的空中,清脆的叫聲不絕于耳,呈現出一幅頗為壯觀的景象。這里聚集的野鴨不下10萬只。

隨著黃河三角洲自然保護“濕地恢復工程”的不斷實施,生態濕地環境日益改善,吸引了眾多珍稀鳥類前來棲息繁衍,其中不乏丹頂鶴、白鸛、白頭鶴等國家一級保護鳥類。這里是國家一類保護珍禽丹頂鶴的重要越冬棲息地,從每年的10月下旬到翌年的3月份,先后有300多只北遷的丹頂鶴來此棲息覓食。

黃河三角洲國家級自然保護區,建于1992年,面積15萬公頃,是以保護新生濕地生態系統和珍稀、瀕危鳥類為主體的濕地類型自然保護區。區內分布著豐富的野生資源,草木本植物393余種,屬國家二級保護的瀕危植物野大豆分布廣泛,天然蘆葦蕩萬余公頃,天然檉柳林數千公頃,其中濱海附近大面積自然紅柳林帶,是中國華東地區目前最大的海灘自然植被區,不僅為保護區增添了壯麗景觀,也為研究原生植被提供了充分的原始資料。初步調查區內豐富的水生生物資源達641種,其中有屬國家二級保護的文昌魚、斑海豹等,還分布著各種珍貴、稀有、瀕危的鳥類,現已證實的283種鳥類中,列為國家一類保護的有5種,二類保護的有41種,世界存量極少的瀕危鳥類黑嘴鷗在保護區內也有較多分布。

黃河三角洲擁有中國暖溫帶保存最完整、最年輕的濕地生態系統,由黃河攜帶大量泥沙填充渤海淤積而成。自20世紀70年代始,黃河斷流加劇了黃河三角洲生態環境的惡化,進入90年代以來,斷流的時間不斷延長,斷流的范圍不斷擴大,1995年實際斷流100天,1996年斷流93天,1997年斷流時間最長達到了226天。近年來雖然黃河斷流得到控制緩解,但從黃河上游注入河口濕地的水量明顯減少,由此也影響了濕地生態系統的平衡。另外,由于海水倒灌引起的侵蝕作用,整個淡水濕地的面積逐年減少,一些依賴濕地生存的動、植物也明顯減少。

對自然保護區的保護是建立在科學研究基礎之上的。保護區的管理人員配合上級有關部門相繼開展了黃河三角洲自然保護區資源調查、北遷涉禽調查、白鶴在黃河三角洲的數量分布及棲息地調查等研究工作,曾多次獲得了國家、省市科研成果獎。1994年保護區被列為濕地水域系統16處具國際意義重點保護地區之一。

2002年黃河三角洲濕地及生態系統可持續發展納入中國濕地保護行動計劃優先項目。在科研的指導下,多項保護工作相繼展開。保護區把管理區域劃分為核心區、緩沖區、試驗區三大部分,實行嚴格的區別管理政策。核心區,屬于絕對保護區,禁止任何單位、個人進入,使其保持自然狀態,按自然規律演替;緩沖區進行非破壞性科學研究、標本采集和從事教學等活動,但不開展旅游等活動;試驗區則有計劃地開展科研、教學、參觀、旅游等活動,與核心區作對比試驗。為了盡快遏止保護區生態環境惡化的狀況,從去年開始實施的總投資684萬元的“生態濕地恢復工程”,被國家林業局立項為重點工程。工程通過引灌黃河水、沿海修筑圍堤,增加濕地的淡水存量,同時強化保護區生態系統的自身調節能力和平衡作用,改善鳥類的生存環境。去年黃河水量較大,引水順利,4238公頃的濕地恢復工程全部完成。為適應鳥類種群、數量增加的需要,自然保護區管理局為鳥類建設了“食堂”和“醫院”,并建立兩處鳥類食物補給區,面積1000公頃,主要養殖貝類等水生物;在黃河口管理站和位于墾利縣的大汶流管理站各建一處200公頃的鳥類食物補給區,種植小麥、谷物等,實行粗放收割為鳥類供食;為救護在遷徙中的傷病鳥,還建成了鳥類救護中心,配備了必要的設施和專職人員。

日益優越的生態條件和充足的食物來源,吸引了眾多珍稀鳥類前來生存繁衍。

Approaching the nature reserve of the Yellow River Delta, where the Yellow River meets the sea, you can see swarming wild ducks fly to the sky from the tussock and water surface and quack one after another, which is truly a marvelous scene. This area provides inhabitancy to more than 100,000 wild ducks.

The national-level nature reserve on the Yellow River Delta was established in 1992. Covering an area of 150,000 hectares, it is a wetlands type nature reserve established to protect the unique ecological system found here as well as the rare and endangered birds which make their homes here. Within the nature reserve, there are abundant wild animal resources and more than 393 kinds of herbaceous and ligneous plants. Wild soybean, a kind of endangered plant under grade two national-level protection, is extensively distributed throughout the reserve, while the natural reed marshes cover an area of more than 10,000 hectares.

The Chinese tamarisk forest found here also covers an area of several thousand hectares. At present, the natural Chinese tamarisk forest belt along the coast is the largest natural vegetation area found on a beach in eastern China. This not only adds a marvelous spectacle to the nature reserve, but also provides abundant primitive materials for study of the protophyta. A preliminary investigation reveals that aquatic animal resources within the nature reserve have amounted to more than 641 kinds, among which amphioxus and spotted seal are under grade two national protection.

In addition, the nature reserve provides inhabitancy for many kinds of precious and endangered birds. Among the 283 kinds of verified birds spotted here, five are under grade one national-level protection and 41 are under grade two protection. Black-beak sea gulls, a kind of endangered bird that is seldom seen in other countries, can be frequently seen in this nature reserve.

The administration department has divided the nature reserve into three parts: core area, buffer area, and experimental area, each with differentiated management policies, which are strictly implemented. The core area is an area under absolute protection, where any construction or trespassing is forbidden in hopes of maintaining the natural status quo and the evolution driven by nature. Non-destructive scientific research, collection of specimens, and teaching sessions are allowed in the buffer area, but tourism is not. Planned scientific research, teaching visits, and tourism are allowed in the experimental area with a view towards making future comparisons with the core area.

In order to restore the deteriorating ecological environment in the nature reserve, the “Restoration Project for Ecological Wetlands” was initiated last year with an investment of 6.84 million yuan and has been chosen by the National Forestry Bureau as a key project. Through diverting water from the Yellow River and constructing a dam along the seashore, this project will increase the fresh water reserves within the nature reserve. Meanwhile, efforts will be made to strengthen the self-regulation ability and balancing function of the nature reserve to improve the living environment of the birds.

Last year, abundant water from the Yellow River enabled the restoration project for 4,238 hectares of wetlands flow smoothly. To meet demands brought about by the increase of bird specimens and numbers, the administration bureau has established “dinning halls” and “hospitals” for the birds. Two food replenishing areas, covering an area of 1000 hectares, have been established so that aquatic animals, such as shellfishes, can be cultivated to provide food for the birds.

In the area of the Yellow River Estuary Administration Station and at the Lawenliu Administration Station of Kenli County, two food replenishing stations, each covering an area of 200 hectares, have been constructed so that wheat and cereal can be planted to provide food for the birds. And in order to save wounded migratory birds, a “first aid” station for birds has been established so that they can be properly cared for by highly trained professionals.

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