陜西(xi)桑園自(zi)然(ran)保(bao)護(hu)區(qu)(qu)是2002年8月經陜西(xi)省人民政府(fu)批準(zhun)成(cheng)立(li)的(de)省級自(zi)然(ran)保(bao)護(hu)區(qu)(qu),后于2009年9月晉(jin)升(sheng)為國家(jia)級自(zi)然(ran)保(bao)護(hu)區(qu)(qu)。
陜西(xi)(xi)桑園國家(jia)級(ji)自然保(bao)護(hu)區(qu)位于秦嶺中段(duan)南坡,漢中市留壩(ba)(ba)縣境內,地(di)(di)跨桑園壩(ba)(ba)鄉(xiang)和(he)江(jiang)口鎮(zhen)兩個鄉(xiang)鎮(zhen),地(di)(di)理坐標(biao)介于東經107o05'~107o21',北(bei)(bei)緯33o39'~33o50',東與太白縣的牛(niu)尾河省(sheng)級(ji)自然保(bao)護(hu)區(qu)接壤,西(xi)(xi)與留壩(ba)(ba)縣桑園壩(ba)(ba)鄉(xiang)的范條峪村(cun)、小(xiao)川子村(cun)以及江(jiang)口鎮(zhen)的元樹村(cun)、鐵礦村(cun)交界(jie),北(bei)(bei)與太白縣的二郎壩(ba)(ba)鄉(xiang)毗鄰,東南與漢西(xi)(xi)摩天(tian)嶺省(sheng)級(ji)自然保(bao)護(hu)區(qu)和(he)洋(yang)縣華陽(yang)鎮(zhen)相連。
陜(shan)西(xi)桑園國(guo)家(jia)級自然(ran)保護區(qu)所在的(de)(de)留壩縣(xian)在大地(di)構造(zao)位置上,地(di)處秦嶺(ling)初(chu)(chu)(chu)皺(zhou)系。以(yi)馬道東西(xi)向(xiang)斷裂為(wei)(wei)界(jie),橫跨兩個(ge)二級構造(zao)單(dan)元(yuan),北(bei)屬秦嶺(ling)印(yin)支(zhi)初(chu)(chu)(chu)皺(zhou)帶(dai),南跨華力西(xi)初(chu)(chu)(chu)皺(zhou)帶(dai)。印(yin)支(zhi)初(chu)(chu)(chu)皺(zhou)帶(dai)在境內居主(zhu)體,細分為(wei)(wei)三(san)個(ge)三(san)級構造(zao)單(dan)元(yuan),由(you)(you)北(bei)至南依(yi)次是(shi):玉皇山(shan)(shan)—桑園壩初(chu)(chu)(chu)皺(zhou)束(shu)(shu);紫柏山(shan)(shan)—摩天嶺(ling)初(chu)(chu)(chu)皺(zhou)束(shu)(shu);閘口(kou)石—鐵佛殿初(chu)(chu)(chu)皺(zhou)束(shu)(shu)。它們是(shi)在晚遠古代地(di)臺(tai)的(de)(de)基(ji)礎上演化而來的(de)(de)漸變(bian)地(di)槽初(chu)(chu)(chu)皺(zhou)帶(dai),具有多旋(xuan)回(hui)發展特點,曾經歷了加(jia)里東、華力西(xi)及(ji)印(yin)支(zhi)三(san)個(ge)旋(xuan)回(hui),且(qie)由(you)(you)南至北(bei),由(you)(you)老至新,逐步演化發展。加(jia)里東旋(xuan)回(hui)由(you)(you)碳硅(gui)質(zhi)、碳酸鹽(yan)巖、泥(ni)(ni)碎屑巖組成(cheng)(cheng),寒武紀發育具一(yi)定的(de)(de)中酸性(xing)火(huo)山(shan)(shan)活動(dong)(dong)。馬道以(yi)北(bei)的(de)(de)廣大地(di)區(qu),加(jia)里東運動(dong)(dong)使(shi)(shi)之一(yi)度隆起,致使(shi)(shi)奧陶(tao)紀沉積(ji)缺失。隨后發育的(de)(de)華力西(xi)、印(yin)支(zhi)旋(xuan)回(hui),以(yi)泥(ni)(ni)盆(pen)—三(san)迭紀泥(ni)(ni)碎屑巖、碳酸鹽(yan)巖沉積(ji)為(wei)(wei)主(zhu),三(san)迭紀的(de)(de)印(yin)支(zhi)運動(dong)(dong)不僅形(xing)成(cheng)(cheng)了秦嶺(ling)印(yin)支(zhi)初(chu)(chu)(chu)皺(zhou)帶(dai),同(tong)時結束(shu)(shu)了秦嶺(ling)地(di)槽系的(de)(de)生命(ming),形(xing)成(cheng)(cheng)了一(yi)些(xie)線(xian)狀初(chu)(chu)(chu)皺(zhou)和不同(tong)類型、不同(tong)規(gui)模的(de)(de)斷裂,并伴有強(qiang)烈(lie)的(de)(de)酸性(xing)巖漿歸入(ru)活動(dong)(dong)和區(qu)域變(bian)質(zhi)作(zuo)用。侏羅紀以(yi)來,在整(zheng)體上升背景下,形(xing)成(cheng)(cheng)了小規(gui)模的(de)(de)中、新生代斷陷盆(pen)地(di)。侏羅紀以(yi)碎屑、泥(ni)(ni)質(zhi)、含煤沉積(ji)建造(zao)為(wei)(wei)特征。
留壩縣(xian)境內群峰(feng)環繞,溝壑縱(zong)橫。由于秦嶺(ling)山(shan)(shan)(shan)(shan)(shan)(shan)地(di)(di)抬升的(de)主(zhu)軸(zhou)偏(pian)北(bei)分(fen)(fen)布,故(gu)整個地(di)(di)勢北(bei)高南(nan)(nan)低(di)。最高海拔2610.2m(紫柏(bo)山(shan)(shan)(shan)(shan)(shan)(shan)主(zhu)峰(feng)),最低(di)海拔585m(青橋驛蔡(cai)家坡谷底)。紫柏(bo)山(shan)(shan)(shan)(shan)(shan)(shan)橫亙縣(xian)境西(xi)(xi)(xi)(xi)北(bei)部(bu)(bu),其東(dong)(dong)(dong)段(duan)與縣(xian)境西(xi)(xi)(xi)(xi)部(bu)(bu)的(de)光(guang)華山(shan)(shan)(shan)(shan)(shan)(shan)、光(guang)頭山(shan)(shan)(shan)(shan)(shan)(shan)、橋頂石(shi)梁、高佛巖等山(shan)(shan)(shan)(shan)(shan)(shan)地(di)(di)連(lian)成南(nan)(nan)北(bei)向(xiang)的(de)嶺(ling)脊;東(dong)(dong)(dong)部(bu)(bu)的(de)摩天嶺(ling)、轉(zhuan)角樓、桅(wei)桿(gan)石(shi)和香爐山(shan)(shan)(shan)(shan)(shan)(shan)連(lian)成東(dong)(dong)(dong)北(bei)與西(xi)(xi)(xi)(xi)南(nan)(nan)走(zou)向(xiang)的(de)分(fen)(fen)水(shui)嶺(ling);北(bei)部(bu)(bu)有玉皇山(shan)(shan)(shan)(shan)(shan)(shan)、三(san)花石(shi)梁等高峰(feng)為屏障(zhang)。全縣(xian)地(di)(di)貌,西(xi)(xi)(xi)(xi)、北(bei)、東(dong)(dong)(dong)三(san)面山(shan)(shan)(shan)(shan)(shan)(shan)嶺(ling)環抱,中、南(nan)(nan)地(di)(di)勢較低(di),形(xing)如簸箕。褒(bao)河(he)自北(bei)而南(nan)(nan)縱(zong)貫東(dong)(dong)(dong)、西(xi)(xi)(xi)(xi)兩嶺(ling)之間,除閘口石(shi)為黑河(he)水(shui)系外,其余均為褒(bao)河(he)水(shui)系。南(nan)(nan)部(bu)(bu)山(shan)(shan)(shan)(shan)(shan)(shan)嶺(ling)陡峭,河(he)谷深切,多(duo)為“V”形(xing)谷,溝地(di)(di)狹窄;北(bei)部(bu)(bu)褒(bao)河(he)支流沿線河(he)谷切割(ge)較淺,山(shan)(shan)(shan)(shan)(shan)(shan)勢開闊(kuo),多(duo)為“U”形(xing)谷,溝地(di)(di)較寬,形(xing)成串珠狀(zhuang)的(de)壩。因(yin)此,按照地(di)(di)貌特點,全縣(xian)可分(fen)(fen)為西(xi)(xi)(xi)(xi)北(bei)部(bu)(bu)高山(shan)(shan)(shan)(shan)(shan)(shan)區(qu)、中部(bu)(bu)中山(shan)(shan)(shan)(shan)(shan)(shan)區(qu)、南(nan)(nan)部(bu)(bu)中低(di)山(shan)(shan)(shan)(shan)(shan)(shan)區(qu)。
桑園自然保(bao)護區(qu)位于(yu)留(liu)壩縣東(dong)(dong)北(bei)部(bu)(bu)(bu),按照(zhao)以上地(di)貌(mao)分(fen)區(qu),屬于(yu)中(zhong)部(bu)(bu)(bu)中(zhong)山區(qu),山巒重疊(die),嶺(ling)谷交錯(cuo),河谷切割較(jiao)(jiao)淺(qian),谷地(di)較(jiao)(jiao)寬。保(bao)護區(qu)東(dong)(dong)北(bei)部(bu)(bu)(bu)、東(dong)(dong)部(bu)(bu)(bu)、東(dong)(dong)南部(bu)(bu)(bu)有烏木梁、團(tuan)包梁、五木梁、摩天嶺(ling)等主要山峰連(lian)貫形(xing)成三面環狀的嶺(ling)脊,因此保(bao)護區(qu)整(zheng)個(ge)地(di)勢呈(cheng)外高內(nei)低的“新月”形(xing)。山體(ti)中(zhong)上部(bu)(bu)(bu)的地(di)形(xing)比較(jiao)(jiao)平緩,下部(bu)(bu)(bu)較(jiao)(jiao)為陡(dou)峭,部(bu)(bu)(bu)分(fen)地(di)段為巖崖,溝地(di)比較(jiao)(jiao)平緩,形(xing)成串珠(zhu)狀的小(xiao)坪、川壩。
陜西桑(sang)園國家級自然保(bao)護區地(di)處北亞熱帶(dai)(dai)山地(di)暖溫帶(dai)(dai)濕(shi)潤季(ji)風氣(qi)(qi)(qi)候區,氣(qi)(qi)(qi)候特點是:冬長夏(xia)短,春秋(qiu)近半,降溫快于升溫,冬冷夏(xia)涼,日(ri)照時(shi)間短,氣(qi)(qi)(qi)候溫涼濕(shi)潤,垂(chui)直(zhi)差異明顯(xian)。
根據留壩縣(xian)的土壤調(diao)查資料,陜西桑(sang)園國家級自然保(bao)護區(qu)的土壤共有2個土類(lei)、6個亞類(lei)、19個土屬。
陜西桑(sang)園國(guo)家級自(zi)(zi)然(ran)保(bao)護區(qu)的(de)(de)(de)水(shui)(shui)系主要屬褒河上游太(tai)白河的(de)(de)(de)上源河段及支流,流域面(mian)(mian)積(ji)約12289hm2,占保(bao)護區(qu)總(zong)面(mian)(mian)積(ji)的(de)(de)(de)89.0%。保(bao)護區(qu)松(song)坪(ping)子(zi)區(qu)域的(de)(de)(de)地表徑流都匯入(ru)黑(hei)峽子(zi)河,經太(tai)白縣的(de)(de)(de)牛(niu)尾河省級自(zi)(zi)然(ran)保(bao)護區(qu),匯入(ru)湑水(shui)(shui)河。這是桑(sang)園自(zi)(zi)然(ran)保(bao)護區(qu)中一塊屬參考資料于(yu)湑水(shui)(shui)河水(shui)(shui)系的(de)(de)(de)區(qu)域,流域面(mian)(mian)積(ji)約1517hm2,占保(bao)護區(qu)總(zong)面(mian)(mian)積(ji)的(de)(de)(de)11.0%。
陜(shan)西(xi)桑園國家(jia)級自然保護區的水系分布呈樹枝(zhi)形。其(qi)中峪長(chang)溝、梨子(zi)壩(ba)(ba)(ba)、范(fan)條(tiao)峪三條(tiao)溝谷(gu)的河(he)水匯(hui)流(liu)成(cheng)桑園壩(ba)(ba)(ba)河(he),全長(chang)19km,流(liu)域面積120.9km2,河(he)流(liu)平均比(bi)降(jiang)31.1‰,在(zai)桑園壩(ba)(ba)(ba)鄉(xiang)政府駐地(di)流(liu)入(ru)太(tai)白河(he)。小川子(zi)、元樹溝、鐵礦溝三條(tiao)溝谷(gu)的河(he)水分別匯(hui)入(ru)桑園壩(ba)(ba)(ba)至江口段的太(tai)白河(he)。
太白河發(fa)源于太白縣,入留壩(ba)縣桑(sang)園壩(ba)鄉(xiang)石(shi)場溝,并有桑(sang)園壩(ba)河匯入,途(tu)徑江口鎮(zhen),在留壩(ba)縣境內全長22.5km,流域面積377.5km2。
褒(bao)河古稱(cheng)黑龍江,發源(yuan)于秦嶺南坡,流經鳳縣、太(tai)白、留壩、漢臺3縣1區,注入漢江。
陜西桑園國家級(ji)自然保護(hu)區(qu)(qu)總(zong)(zong)面積(ji)13806公(gong)(gong)頃(qing),其(qi)中國有林(lin)(lin)9342公(gong)(gong)頃(qing),占(zhan)保護(hu)區(qu)(qu)總(zong)(zong)面積(ji)的67.7%,集體林(lin)(lin)4464公(gong)(gong)頃(qing),占(zhan)保護(hu)區(qu)(qu)總(zong)(zong)面積(ji)的32.3%。功能區(qu)(qu)劃:核心區(qu)(qu)為8796.02公(gong)(gong)頃(qing),占(zhan)保護(hu)區(qu)(qu)總(zong)(zong)面積(ji)的63.71%;緩沖區(qu)(qu)為2620.65公(gong)(gong)頃(qing),占(zhan)保護(hu)區(qu)(qu)總(zong)(zong)面積(ji)的18.98%;實驗(yan)區(qu)(qu)為2389.33公(gong)(gong)頃(qing),占(zhan)保護(hu)區(qu)(qu)總(zong)(zong)面積(ji)的17.31%。
陜西桑(sang)園國家級自然(ran)保(bao)護區是以大熊貓及(ji)其棲息地(di)為主要保(bao)護對象(xiang)的野(ye)生(sheng)動(dong)物類型自然(ran)保(bao)護區。
截止到(dao)2008年,通過科學考察表明(ming),保(bao)護區(qu)有(you)高等維管束植物(wu)1099種(zhong)(zhong)(zhong)(zhong),野生脊椎動(dong)物(wu)249種(zhong)(zhong)(zhong)(zhong),大型真菌(jun)68種(zhong)(zhong)(zhong)(zhong),昆蟲1353種(zhong)(zhong)(zhong)(zhong)。在(zai)這些(xie)眾多的物(wu)種(zhong)(zhong)(zhong)(zhong)中(zhong),有(you)紅豆杉、秦(qin)嶺冷杉、連(lian)香樹、水(shui)青(qing)樹、水(shui)曲柳等國(guo)家一、二級珍(zhen)稀保(bao)護植物(wu)9種(zhong)(zhong)(zhong)(zhong)。在(zai)保(bao)護區(qu)的主峰摩天嶺分布(bu)有(you)近2000公頃(qing)面積的秦(qin)嶺冷杉群,其(qi)規模在(zai)整個秦(qin)嶺地區(qu)較(jiao)為罕見。
除植(zhi)(zhi)物(wu)資(zi)(zi)(zi)源(yuan)(yuan)外,保(bao)護(hu)(hu)區的(de)野(ye)生動物(wu)資(zi)(zi)(zi)源(yuan)(yuan)也非常豐富(fu),截(jie)止(zhi)到2008年(nian),有(you)國家一級保(bao)護(hu)(hu)野(ye)生動物(wu)6種(zhong):如(ru)大(da)熊(xiong)(xiong)(xiong)貓、金絲猴、羚(ling)牛、林麝等(deng)(deng);二級保(bao)護(hu)(hu)野(ye)生動物(wu)24種(zhong):如(ru)黑熊(xiong)(xiong)(xiong)、大(da)鯢、大(da)鵟、鬣羚(ling)、斑羚(ling)等(deng)(deng)。保(bao)護(hu)(hu)區主要范圍(wei)為(wei)大(da)熊(xiong)(xiong)(xiong)貓的(de)適宜棲息地,面積(ji)(ji)為(wei)11508公頃,占保(bao)護(hu)(hu)區總(zong)面積(ji)(ji)的(de)83.4%。除動植(zhi)(zhi)物(wu)資(zi)(zi)(zi)源(yuan)(yuan)外,保(bao)護(hu)(hu)區內還有(you)摩天(tian)嶺、奎心樓、紅花(hua)嶒瀑(pu)布等(deng)(deng)以高、寒(han)、奇、險為(wei)特色的(de)天(tian)然旅(lv)游景(jing)觀資(zi)(zi)(zi)源(yuan)(yuan)。
陜西(xi)桑園(yuan)(yuan)國家級(ji)自然保護(hu)區管理機(ji)構為陜西(xi)桑園(yuan)(yuan)自然保護(hu)區管理局。機(ji)關設(she)保護(hu)區綜(zong)合辦(ban)公室,財務室,基層設(she)有桑園(yuan)(yuan)中心站(zhan)、上(shang)兩河口保護(hu)站(zhan),財神廟保護(hu)站(zhan),梨子壩保護(hu)站(zhan)、小川子保護(hu)站(zhan)、下田灣保護(hu)站(zhan)。
1984年(nian)(nian)(nian),在(zai)陜(shan)西桑園國家(jia)級自然(ran)保護(hu)區的磚頭(tou)壩附近救(jiu)護(hu)了大熊(xiong)(xiong)(xiong)(xiong)貓(mao)(mao)(mao)“留留”,這是第(di)一(yi)次明(ming)確證實保護(hu)區有(you)大熊(xiong)(xiong)(xiong)(xiong)貓(mao)(mao)(mao)分布(bu)。陜(shan)西省林業廳(ting)1986年(nian)(nian)(nian)組織的全(quan)省大熊(xiong)(xiong)(xiong)(xiong)貓(mao)(mao)(mao)調查結果顯(xian)(xian)示,保護(hu)區所在(zai)地有(you)大熊(xiong)(xiong)(xiong)(xiong)貓(mao)(mao)(mao)2只(zhi)。1999~2003年(nian)(nian)(nian)的全(quan)國第(di)三次大熊(xiong)(xiong)(xiong)(xiong)貓(mao)(mao)(mao)調查結果顯(xian)(xian)示,保護(hu)區所在(zai)地有(you)大熊(xiong)(xiong)(xiong)(xiong)貓(mao)(mao)(mao)7只(zhi),大熊(xiong)(xiong)(xiong)(xiong)貓(mao)(mao)(mao)棲(qi)息(xi)地面積約11508hm2,占保護(hu)區總面積的83.4%。2005年(nian)(nian)(nian)陜(shan)西省又在(zai)鳳(feng)縣(xian)靠近留壩縣(xian)的紫柏山(shan)一(yi)帶發現大熊(xiong)(xiong)(xiong)(xiong)貓(mao)(mao)(mao)新(xin)的分布(bu)區。
陜(shan)西桑園國家級自然保(bao)護(hu)區(qu)(qu)是秦(qin)嶺(ling)中段(duan)大(da)(da)熊(xiong)貓(mao)種群向(xiang)西擴散的(de)必經之地,是實現秦(qin)嶺(ling)中、西段(duan)大(da)(da)熊(xiong)貓(mao)居群有(you)效連接的(de)重(zhong)要希望所(suo)在,加強該保(bao)護(hu)區(qu)(qu)的(de)保(bao)護(hu)管理意義(yi)重(zhong)大(da)(da)。陜(shan)西桑園國家級自然保(bao)護(hu)區(qu)(qu)地處漢江支(zhi)流褒河和湑水河的(de)上游,在涵(han)養水源、保(bao)持(chi)水土(tu)、防風固沙、凈化空氣、改善區(qu)(qu)域環境質量等方面都發揮(hui)著十分(fen)重(zhong)要的(de)作用。