芒果视频

云霧(wu)山自(zi)然(ran)(ran)保(bao)護區（Yunwushan Nature Re-Serve） 中(zhong)國(guo)第(di)2個(ge)(ge)草(cao)(cao)(cao)原(yuan)(yuan)保(bao)護區。屬(shu)黃土(tu)高原(yuan)(yuan)長芒(mang)草(cao)(cao)(cao)群(qun)系保(bao)留較好(hao)的(de)典型地區，對開展草(cao)(cao)(cao)原(yuan)(yuan)生態系統的(de)定(ding)位研究，探索草(cao)(cao)(cao)原(yuan)(yuan)、畜牧、水土(tu)保(bao)持(chi)間(jian)的(de)關系有重(zhong)要科研價值(zhi)。位于寧夏固原(yuan)(yuan)縣東北，為(wei)中(zhong)溫帶半干(gan)旱黃土(tu)丘陵低山區。已劃定(ding)自(zi)然(ran)(ran)保(bao)護區面積1300公頃(qing)。海拔多(duo)在1800～1900米，頂峰2148米。年(nian)(nian)均(jun)溫6℃，年(nian)(nian)降水量(liang)約(yue)350～400毫米，土(tu)壤(rang)主要為(wei)淡黑(hei)壚土(tu)。有種(zhong)(zhong)(zhong)子植(zhi)(zhi)物181種(zhong)(zhong)(zhong)，其中(zhong)草(cao)(cao)(cao)本植(zhi)(zhi)物140多(duo)種(zhong)(zhong)(zhong)，包括(kuo)飼(si)用(yong)植(zhi)(zhi)物110種(zhong)(zhong)(zhong)，藥(yao)用(yong)植(zhi)(zhi)物41種(zhong)(zhong)(zhong)；脊椎動物80種(zhong)(zhong)(zhong)。共有典型草(cao)(cao)(cao)原(yuan)(yuan)、草(cao)(cao)(cao)甸草(cao)(cao)(cao)原(yuan)(yuan)、荒漠草(cao)(cao)(cao)原(yuan)(yuan)、中(zhong)生落(luo)(luo)葉闊葉灌叢和耐(nai)旱落(luo)(luo)葉灌叢等5個(ge)(ge)植(zhi)(zhi)被亞型，11個(ge)(ge)重(zhong)要群(qun)系。其中(zhong)以典型草(cao)(cao)(cao)原(yuan)(yuan)的(de)長芒(mang)草(cao)(cao)(cao)群(qun)系占優勢，為(wei)黃土(tu)高原(yuan)(yuan)叢生禾草(cao)(cao)(cao)草(cao)(cao)(cao)原(yuan)(yuan)的(de)代表類型。其次為(wei)百里香、鐵桿(gan)蒿(hao)、茭蒿(hao)、委陵菜等。經幾(ji)年(nian)(nian)來的(de)保(bao)護，草(cao)(cao)(cao)場生產力已由畝產鮮草(cao)(cao)(cao)100～150千(qian)(qian)克提高到400～600千(qian)(qian)克，是良好(hao)的(de)常年(nian)(nian)牧場。

歷史

1982年，固原縣(xian)在(zai)云(yun)霧山建立(li)了(le)面積達4000公頃(qing)的草原自然(ran)(ran)保(bao)護(hu)區，1995年被列為省(區)級自然(ran)(ran)保(bao)護(hu)區，這(zhe)也是我(wo)國黃土高原建立(li)的第(di)一個草地類自然(ran)(ran)保(bao)護(hu)區。

地理環境

云霧山主

云霧(wu)山(shan)草(cao)原(yuan)自然保護(hu)區峰海拔2128米(mi)，山(shan)基由白云巖、紅色砂礫組成，土壤為地灰褐土和(he)淡(dan)黑壚土，生長草(cao)甸植被(bei)。

自然資源

保護(hu)(hu)區內有(you)植物51科131屬182種(zhong)，動物40科74屬80種(zhong)，益蟲14科28種(zhong)，蜘蛛5科7種(zhong)。保護(hu)(hu)區所保護(hu)(hu)的(de)對象就是這(zhe)些草(cao)原植被及其(qi)生(sheng)(sheng)態系統(tong)，包(bao)括氣候(hou)、土壤、昆蟲、野生(sheng)(sheng)動植物、微生(sheng)(sheng)物等(deng)。

生態保護

自80年云霧山草原(yuan)自然保護(hu)區自然風光代中(zhong)期于日本、美國(guo)、德(de)國(guo)等生態(tai)(tai)(tai)學(xue)(xue)(xue)、土壤學(xue)(xue)(xue)和生物(wu)多樣性等方(fang)面的科(ke)(ke)學(xue)(xue)(xue)家(jia)開展了合作研(yan)(yan)(yan)究(jiu)，目前已成為(wei)(wei)中(zhong)國(guo)科(ke)(ke)學(xue)(xue)(xue)院水利部(bu)水土保持研(yan)(yan)(yan)究(jiu)所、西北(bei)農林(lin)(lin)科(ke)(ke)技(ji)大(da)學(xue)(xue)(xue)、蘭州大(da)學(xue)(xue)(xue)、寧夏大(da)學(xue)(xue)(xue)草業(ye)科(ke)(ke)學(xue)(xue)(xue)研(yan)(yan)(yan)究(jiu)與研(yan)(yan)(yan)究(jiu)生培(pei)養(yang)、農業(ye)部(bu)狐貍野(ye)性化馴養(yang)和國(guo)家(jia)林(lin)(lin)業(ye)局退化生態(tai)(tai)(tai)系統(tong)定(ding)位(wei)監測基地及全(quan)球氣候變化定(ding)位(wei)監測點，經過近(jin)30年的封禁和草原(yuan)生態(tai)(tai)(tai)系統(tong)定(ding)位(wei)監測研(yan)(yan)(yan)究(jiu)，生態(tai)(tai)(tai)經濟(ji)社會效(xiao)益顯著，已成為(wei)(wei)我國(guo)西部(bu)草原(yuan)植被恢(hui)復與草原(yuan)自然修復的一個成功(gong)典范，為(wei)(wei)國(guo)家(jia)退耕還(huan)林(lin)(lin)草與地方(fang)封山禁牧工(gong)程的實(shi)施(shi)提供(gong)了重要科(ke)(ke)學(xue)(xue)(xue)依據。

天然草地自然修復成效顯著

20世(shi)紀80年(nian)代(dai)初(chu)期，在(zai)(zai)(zai)區域考察(cha)的(de)基礎上(shang)，我(wo)們提(ti)出并在(zai)(zai)(zai)我(wo)國(guo)西部寧(ning)夏固原(yuan)云霧山(shan)(shan)建(jian)立了(le)(le)最早的(de)典型草(cao)(cao)(cao)(cao)(cao)原(yuan)自然保(bao)(bao)(bao)護(hu)區，封(feng)禁(jin)(jin)保(bao)(bao)(bao)護(hu)面積(ji)由0.23萬(wan)hm已(yi)擴大(da)(da)到(dao)1 萬(wan)hm。通過(guo)近30年(nian)封(feng)禁(jin)(jin)定(ding)位試驗，根據草(cao)(cao)(cao)(cao)(cao)地(di)(di)(di)退(tui)化程度(du)(du)(du)采取(qu)封(feng)禁(jin)(jin)、改良、補播等(deng)草(cao)(cao)(cao)(cao)(cao)地(di)(di)(di)建(jian)設技術途徑，使(shi)退(tui)化草(cao)(cao)(cao)(cao)(cao)地(di)(di)(di)植(zhi)(zhi)被種(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)類(lei)成分(fen)(fen)、牧(mu)草(cao)(cao)(cao)(cao)(cao)生(sheng)(sheng)(sheng)(sheng)長(chang)發(fa)育和(he)(he)草(cao)(cao)(cao)(cao)(cao)地(di)(di)(di)生(sheng)(sheng)(sheng)(sheng)境條(tiao)件得到(dao)了(le)(le)全面改善(shan)，草(cao)(cao)(cao)(cao)(cao)地(di)(di)(di)生(sheng)(sheng)(sheng)(sheng)產力(li)有了(le)(le)很大(da)(da)提(ti)高，草(cao)(cao)(cao)(cao)(cao)群(qun)種(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)類(lei)成分(fen)(fen)發(fa)生(sheng)(sheng)(sheng)(sheng)了(le)(le)顯著(zhu)變化。封(feng)禁(jin)(jin)初(chu)期，草(cao)(cao)(cao)(cao)(cao)原(yuan)植(zhi)(zhi)物(wu)(wu)僅為(wei)53種(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)，其(qi)中(zhong)灌木(mu)和(he)(he)半灌木(mu)占(zhan)(zhan)8%，草(cao)(cao)(cao)(cao)(cao)本占(zhan)(zhan)92%，多(duo)數(shu)(shu)(shu)以旱(han)(han)生(sheng)(sheng)(sheng)(sheng)植(zhi)(zhi)物(wu)(wu)組成，物(wu)(wu)種(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)密(mi)(mi)度(du)(du)(du)平均為(wei)5種(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)/m。隨封(feng)禁(jin)(jin)期延(yan)長(chang)物(wu)(wu)種(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)密(mi)(mi)度(du)(du)(du)逐漸增(zeng)加，封(feng)禁(jin)(jin)的(de)第15年(nian)(1996年(nian))，物(wu)(wu)種(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)密(mi)(mi)度(du)(du)(du)達(da)到(dao)了(le)(le)峰值，平均為(wei)33種(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)/m，是(shi)(shi)未(wei)封(feng)禁(jin)(jin)的(de)3.1倍，草(cao)(cao)(cao)(cao)(cao)地(di)(di)(di)群(qun)落(luo)物(wu)(wu)種(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)種(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)數(shu)(shu)(shu)達(da)到(dao)186種(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)，是(shi)(shi)未(wei)封(feng)禁(jin)(jin)的(de)3.5倍，其(qi)中(zhong)灌木(mu)和(he)(he)半灌木(mu)占(zhan)(zhan)12%，草(cao)(cao)(cao)(cao)(cao)本占(zhan)(zhan)88%，多(duo)數(shu)(shu)(shu)以中(zhong)生(sheng)(sheng)(sheng)(sheng)和(he)(he)中(zhong)旱(han)(han)生(sheng)(sheng)(sheng)(sheng)植(zhi)(zhi)物(wu)(wu)組成，并出現大(da)(da)量(liang)森林(lin)草(cao)(cao)(cao)(cao)(cao)原(yuan)地(di)(di)(di)帶的(de)灌木(mu)和(he)(he)草(cao)(cao)(cao)(cao)(cao)本植(zhi)(zhi)物(wu)(wu)種(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)。草(cao)(cao)(cao)(cao)(cao)地(di)(di)(di)覆蓋度(du)(du)(du)由35%提(ti)高到(dao)95%，生(sheng)(sheng)(sheng)(sheng)物(wu)(wu)量(liang)由750提(ti)高到(dao)7560kg/hm。特別是(shi)(shi)在(zai)(zai)(zai)1986和(he)(he)1991年(nian)降(jiang)(jiang)雨量(liang)274.8mm和(he)(he)259.7mm的(de)大(da)(da)旱(han)(han)年(nian)份，寧(ning)夏固原(yuan)2/3的(de)地(di)(di)(di)方(fang)由于干旱(han)(han)缺草(cao)(cao)(cao)(cao)(cao)造(zao)成60%~70%牲畜(chu)死亡，但封(feng)禁(jin)(jin)保(bao)(bao)(bao)護(hu)和(he)(he)改良草(cao)(cao)(cao)(cao)(cao)地(di)(di)(di)周圍的(de)鄉村5.0~6.0萬(wan)頭牲畜(chu)得到(dao)了(le)(le)挽救，直接減少經(jing)濟(ji)損失500萬(wan)元，充分(fen)(fen)發(fa)揮了(le)(le)"自然保(bao)(bao)(bao)護(hu)區"和(he)(he)改良草(cao)(cao)(cao)(cao)(cao)地(di)(di)(di)的(de)顯著(zhu)作(zuo)用，保(bao)(bao)(bao)護(hu)區生(sheng)(sheng)(sheng)(sheng)態、經(jing)濟(ji)、社會(hui)效益顯著(zhu)，受到(dao)了(le)(le)各級政府(fu)及群(qun)眾的(de)一致贊揚，得到(dao)了(le)(le)地(di)(di)(di)方(fang)政府(fu)表(biao)(biao)彰和(he)(he)獎(jiang)勵(li)。但封(feng)禁(jin)(jin)15年(nian)后隨封(feng)禁(jin)(jin)時間(jian)的(de)延(yan)長(chang)，物(wu)(wu)種(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)密(mi)(mi)度(du)(du)(du)趨于下降(jiang)(jiang)，第24-28年(nian)(2008年(nian))物(wu)(wu)種(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)密(mi)(mi)度(du)(du)(du)僅為(wei)19.1種(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)/m。封(feng)禁(jin)(jin)期過(guo)長(chang)因枯草(cao)(cao)(cao)(cao)(cao)層加厚(hou)而影響草(cao)(cao)(cao)(cao)(cao)地(di)(di)(di)自然更新(xin)與物(wu)(wu)種(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)多(duo)樣(yang)性增(zeng)加。草(cao)(cao)(cao)(cao)(cao)地(di)(di)(di)土(tu)(tu)壤種(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)子庫(ku)研究表(biao)(biao)明，云霧山(shan)(shan)草(cao)(cao)(cao)(cao)(cao)地(di)(di)(di)土(tu)(tu)壤種(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)子庫(ku)在(zai)(zai)(zai)空間(jian)分(fen)(fen)布(bu)上(shang)呈現一定(ding)的(de)規律性，種(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)子密(mi)(mi)度(du)(du)(du)在(zai)(zai)(zai)垂直分(fen)(fen)布(bu)上(shang)呈現出由表(biao)(biao)層土(tu)(tu)壤向深層逐層減少的(de)變化規律，水平分(fen)(fen)布(bu)上(shang)變化規律為(wei):封(feng)禁(jin)(jin)>放牧(mu);陰坡(po)(po)>陽(yang)坡(po)(po);下坡(po)(po)>中(zhong)坡(po)(po)>上(shang)坡(po)(po)，這些均是(shi)(shi)影響群(qun)落(luo)物(wu)(wu)種(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)(zhong)多(duo)樣(yang)性增(zeng)加和(he)(he)草(cao)(cao)(cao)(cao)(cao)地(di)(di)(di)繁殖更新(xin)的(de)關鍵問題。

通(tong)過(guo)(guo)近30年(nian)(nian)的(de)自然(ran)封(feng)禁(jin)(jin)試驗(yan)(yan)，明確提(ti)出草(cao)地恢(hui)(hui)復的(de)適(shi)宜封(feng)禁(jin)(jin)期(qi)(qi)(qi):在半干旱區森林草(cao)原(yuan)(yuan)地帶(dai)(dai)，草(cao)甸植(zhi)(zhi)被(bei)(bei)(bei)(bei)(bei)的(de)適(shi)宜恢(hui)(hui)復期(qi)(qi)(qi)為3~5年(nian)(nian)，方可(ke)進(jin)(jin)行合理(li)的(de)放(fang)牧或刈(yi)割(ge)利(li)用(yong)，對利(li)用(yong)過(guo)(guo)度退化(hua)嚴(yan)重(zhong)的(de)草(cao)甸植(zhi)(zhi)被(bei)(bei)(bei)(bei)(bei)在平水(shui)年(nian)(nian)需要封(feng)禁(jin)(jin)8~12年(nian)(nian);在典型草(cao)原(yuan)(yuan)地帶(dai)(dai)，草(cao)地植(zhi)(zhi)被(bei)(bei)(bei)(bei)(bei)適(shi)宜恢(hui)(hui)復期(qi)(qi)(qi)為5~8年(nian)(nian)，方可(ke)進(jin)(jin)行合理(li)刈(yi)割(ge)和(he)(he)放(fang)牧利(li)用(yong)，退化(hua)嚴(yan)重(zhong)的(de)草(cao)地植(zhi)(zhi)被(bei)(bei)(bei)(bei)(bei)在平水(shui)年(nian)(nian)約(yue)需封(feng)禁(jin)(jin)10~15年(nian)(nian);在荒漠(mo)草(cao)原(yuan)(yuan)地帶(dai)(dai)，草(cao)地植(zhi)(zhi)被(bei)(bei)(bei)(bei)(bei)適(shi)宜恢(hui)(hui)復期(qi)(qi)(qi)為10~12年(nian)(nian)，方可(ke)進(jin)(jin)行合理(li)的(de)刈(yi)割(ge)和(he)(he)放(fang)牧利(li)用(yong)，退化(hua)嚴(yan)重(zhong)草(cao)地在平水(shui)年(nian)(nian)約(yue)需封(feng)禁(jin)(jin)15~20年(nian)(nian)。這一結論通(tong)過(guo)(guo)多(duo)年(nian)(nian)的(de)試驗(yan)(yan)驗(yan)(yan)證，已(yi)建(jian)立了示范(fan)樣板，為同類型區天然(ran)植(zhi)(zhi)被(bei)(bei)(bei)(bei)(bei)恢(hui)(hui)復利(li)用(yong)提(ti)供了重(zhong)要科學依據(ju)。

封禁草地自然演替過程與規律

通過近30年(nian)的(de)(de)(de)(de)(de)封(feng)(feng)禁試(shi)驗，首次(ci)劃分(fen)了草(cao)地植(zhi)被恢(hui)復(fu)(fu)與(yu)時序演替(ti)過程，分(fen)為(wei)(wei)(wei)(wei)五(wu)個(ge)(ge)階(jie)(jie)段(duan)(duan)(duan):第(di)(di)一階(jie)(jie)段(duan)(duan)(duan)為(wei)(wei)(wei)(wei)種(zhong)(zhong)(zhong)(zhong)群(qun)(qun)(qun)持續增(zeng)(zeng)長(chang)聚(ju)集階(jie)(jie)段(duan)(duan)(duan)，即在(zai)封(feng)(feng)禁的(de)(de)(de)(de)(de)1~3年(nian)內以(yi)本(ben)(ben)(ben)氏針茅(mao)鄉土種(zhong)(zhong)(zhong)(zhong)為(wei)(wei)(wei)(wei)主的(de)(de)(de)(de)(de)建群(qun)(qun)(qun)種(zhong)(zhong)(zhong)(zhong)與(yu)其它優勢種(zhong)(zhong)(zhong)(zhong)、伴生(sheng)(sheng)(sheng)種(zhong)(zhong)(zhong)(zhong)和偶(ou)見(jian)種(zhong)(zhong)(zhong)(zhong)不(bu)斷適(shi)(shi)應(ying)新(xin)的(de)(de)(de)(de)(de)生(sheng)(sheng)(sheng)境，各項生(sheng)(sheng)(sheng)長(chang)指(zhi)標(biao)穩定增(zeng)(zeng)長(chang);第(di)(di)二階(jie)(jie)段(duan)(duan)(duan)為(wei)(wei)(wei)(wei)種(zhong)(zhong)(zhong)(zhong)間(jian)激(ji)烈(lie)(lie)競爭階(jie)(jie)段(duan)(duan)(duan)，也是封(feng)(feng)禁的(de)(de)(de)(de)(de)第(di)(di)4~9年(nian)，植(zhi)物(wu)數(shu)(shu)(shu)量(liang)(liang)(liang)大幅(fu)度(du)增(zeng)(zeng)長(chang)，并適(shi)(shi)應(ying)了新(xin)的(de)(de)(de)(de)(de)生(sheng)(sheng)(sheng)境，且相互展(zhan)開了激(ji)烈(lie)(lie)的(de)(de)(de)(de)(de)種(zhong)(zhong)(zhong)(zhong)間(jian)競爭與(yu)自(zi)然選(xuan)擇;第(di)(di)三階(jie)(jie)段(duan)(duan)(duan)為(wei)(wei)(wei)(wei)建群(qun)(qun)(qun)種(zhong)(zhong)(zhong)(zhong)加速恢(hui)復(fu)(fu)演替(ti)階(jie)(jie)段(duan)(duan)(duan)，即封(feng)(feng)禁的(de)(de)(de)(de)(de)10~15年(nian)，植(zhi)物(wu)在(zai)激(ji)烈(lie)(lie)的(de)(de)(de)(de)(de)種(zhong)(zhong)(zhong)(zhong)間(jian)競爭中"物(wu)競天(tian)擇、適(shi)(shi)者(zhe)生(sheng)(sheng)(sheng)存"，本(ben)(ben)(ben)氏針茅(mao)形成明顯建群(qun)(qun)(qun)種(zhong)(zhong)(zhong)(zhong)，并不(bu)斷加速種(zhong)(zhong)(zhong)(zhong)群(qun)(qun)(qun)自(zi)身的(de)(de)(de)(de)(de)恢(hui)復(fu)(fu)與(yu)擴展(zhan), 且已達到"亞(ya)頂極";第(di)(di)四階(jie)(jie)段(duan)(duan)(duan)為(wei)(wei)(wei)(wei)建群(qun)(qun)(qun)種(zhong)(zhong)(zhong)(zhong)的(de)(de)(de)(de)(de)定居生(sheng)(sheng)(sheng)長(chang)階(jie)(jie)段(duan)(duan)(duan)，封(feng)(feng)禁的(de)(de)(de)(de)(de)16~21年(nian)本(ben)(ben)(ben)氏針茅(mao)種(zhong)(zhong)(zhong)(zhong)群(qun)(qun)(qun)個(ge)(ge)體數(shu)(shu)(shu)量(liang)(liang)(liang)的(de)(de)(de)(de)(de)變化(hua)基(ji)本(ben)(ben)(ben)穩定在(zai)19株(zhu)/m，占群(qun)(qun)(qun)落(luo)總(zong)數(shu)(shu)(shu)的(de)(de)(de)(de)(de)90.5%，已達到"亞(ya)頂極";第(di)(di)五(wu)階(jie)(jie)段(duan)(duan)(duan)22~28年(nian)本(ben)(ben)(ben)氏針茅(mao)種(zhong)(zhong)(zhong)(zhong)群(qun)(qun)(qun)的(de)(de)(de)(de)(de)生(sheng)(sheng)(sheng)長(chang)繁殖受枯草(cao)層的(de)(de)(de)(de)(de)影響，個(ge)(ge)體數(shu)(shu)(shu)量(liang)(liang)(liang)急劇下降(jiang)，優勢種(zhong)(zhong)(zhong)(zhong)大針茅(mao)種(zhong)(zhong)(zhong)(zhong)群(qun)(qun)(qun)的(de)(de)(de)(de)(de)數(shu)(shu)(shu)量(liang)(liang)(liang)巨增(zeng)(zeng)，密(mi)度(du)為(wei)(wei)(wei)(wei)16~26株(zhu)/m，有替(ti)代(dai)本(ben)(ben)(ben)氏針茅(mao)的(de)(de)(de)(de)(de)趨(qu)勢。同時在(zai)草(cao)原(yuan)(yuan)群(qun)(qun)(qun)落(luo)生(sheng)(sheng)(sheng)長(chang)的(de)(de)(de)(de)(de)溝(gou)道還(huan)出現(xian)大量(liang)(liang)(liang)的(de)(de)(de)(de)(de)中生(sheng)(sheng)(sheng)灌木，多為(wei)(wei)(wei)(wei)森(sen)林(lin)(lin)草(cao)原(yuan)(yuan)區成分(fen)，已由草(cao)原(yuan)(yuan)群(qun)(qun)(qun)落(luo)坡下部(bu)的(de)(de)(de)(de)(de)陰(yin)坡或半(ban)陰(yin)坡以(yi)片狀分(fen)布(bu)，逐漸(jian)向草(cao)原(yuan)(yuan)腹地呈零星狀入侵，使草(cao)原(yuan)(yuan)群(qun)(qun)(qun)落(luo)的(de)(de)(de)(de)(de)演替(ti)進入了一個(ge)(ge)重要的(de)(de)(de)(de)(de)階(jie)(jie)段(duan)(duan)(duan)，形成了一個(ge)(ge)明顯的(de)(de)(de)(de)(de)拐點，直到封(feng)(feng)禁的(de)(de)(de)(de)(de)第(di)(di)28年(nian)物(wu)種(zhong)(zhong)(zhong)(zhong)豐(feng)富度(du)仍保持在(zai)148種(zhong)(zhong)(zhong)(zhong)，具有典(dian)型草(cao)原(yuan)(yuan)群(qun)(qun)(qun)落(luo)向森(sen)林(lin)(lin)草(cao)原(yuan)(yuan)群(qun)(qun)(qun)落(luo)類型演替(ti)發(fa)展(zhan)的(de)(de)(de)(de)(de)趨(qu)勢。

封禁草地適度刈割利用技術

在黃土高原典型草原地帶，通過不同刈割(ge)強(qiang)度(du)試驗，表明適(shi)度(du)刈割(ge)可(ke)使草地保持(chi)較高的物種多樣性(xing)和生產力，并能(neng)促進草地物質平衡(heng)及良性(xing)循(xun)環，為(wei)封禁草地的合理刈割(ge)利用提供了重要(yao)依據。