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云霧山自然保(bao)護區(qu)（Yunwushan Nature Re-Serve） 中(zhong)(zhong)國第2個(ge)草(cao)(cao)原(yuan)(yuan)(yuan)保(bao)護區(qu)。屬黃(huang)(huang)土(tu)高原(yuan)(yuan)(yuan)長芒草(cao)(cao)群系(xi)保(bao)留較好(hao)的(de)(de)典(dian)型(xing)(xing)地區(qu)，對開展草(cao)(cao)原(yuan)(yuan)(yuan)生態系(xi)統的(de)(de)定位(wei)(wei)研(yan)究，探索草(cao)(cao)原(yuan)(yuan)(yuan)、畜(chu)牧、水土(tu)保(bao)持(chi)間的(de)(de)關系(xi)有重(zhong)要(yao)科研(yan)價(jia)值。位(wei)(wei)于寧夏固原(yuan)(yuan)(yuan)縣東北，為中(zhong)(zhong)溫(wen)(wen)帶(dai)半干旱(han)黃(huang)(huang)土(tu)丘(qiu)陵低(di)山區(qu)。已(yi)劃定自然保(bao)護區(qu)面(mian)積1300公頃。海拔多在1800～1900米，頂峰2148米。年均溫(wen)(wen)6℃，年降水量約(yue)350～400毫(hao)米，土(tu)壤主要(yao)為淡黑壚土(tu)。有種(zhong)子植(zhi)物181種(zhong)，其(qi)(qi)中(zhong)(zhong)草(cao)(cao)本植(zhi)物140多種(zhong)，包(bao)括飼用植(zhi)物110種(zhong)，藥用植(zhi)物41種(zhong)；脊椎動(dong)物80種(zhong)。共(gong)有典(dian)型(xing)(xing)草(cao)(cao)原(yuan)(yuan)(yuan)、草(cao)(cao)甸草(cao)(cao)原(yuan)(yuan)(yuan)、荒漠草(cao)(cao)原(yuan)(yuan)(yuan)、中(zhong)(zhong)生落葉(xie)(xie)闊葉(xie)(xie)灌叢(cong)和耐旱(han)落葉(xie)(xie)灌叢(cong)等(deng)5個(ge)植(zhi)被亞型(xing)(xing)，11個(ge)重(zhong)要(yao)群系(xi)。其(qi)(qi)中(zhong)(zhong)以典(dian)型(xing)(xing)草(cao)(cao)原(yuan)(yuan)(yuan)的(de)(de)長芒草(cao)(cao)群系(xi)占優勢(shi)，為黃(huang)(huang)土(tu)高原(yuan)(yuan)(yuan)叢(cong)生禾草(cao)(cao)草(cao)(cao)原(yuan)(yuan)(yuan)的(de)(de)代(dai)表(biao)類型(xing)(xing)。其(qi)(qi)次(ci)為百里香(xiang)、鐵(tie)桿蒿、茭蒿、委陵菜等(deng)。經幾(ji)年來的(de)(de)保(bao)護，草(cao)(cao)場生產力已(yi)由畝(mu)產鮮草(cao)(cao)100～150千克提高到400～600千克，是良好(hao)的(de)(de)常年牧場。

歷史

1982年，固原縣(xian)在云霧山(shan)建(jian)立了(le)面積達4000公頃(qing)的草(cao)原自然(ran)保(bao)護(hu)(hu)區(qu)，1995年被(bei)列為省(區(qu))級自然(ran)保(bao)護(hu)(hu)區(qu)，這也是我國黃土高原建(jian)立的第一個草(cao)地類自然(ran)保(bao)護(hu)(hu)區(qu)。

地理環境

云霧山主

云(yun)(yun)霧山草(cao)原自然保(bao)護區峰海拔(ba)2128米，山基(ji)由白云(yun)(yun)巖、紅色砂礫組成，土壤(rang)為地(di)灰褐土和淡(dan)黑壚土，生長草(cao)甸(dian)植被。

自然資源

保(bao)(bao)護(hu)區內有植(zhi)物51科131屬182種(zhong)，動(dong)(dong)物40科74屬80種(zhong)，益(yi)蟲14科28種(zhong)，蜘蛛5科7種(zhong)。保(bao)(bao)護(hu)區所保(bao)(bao)護(hu)的對象就是這(zhe)些草原植(zhi)被及其生態系統，包(bao)括(kuo)氣(qi)候、土壤、昆(kun)蟲、野(ye)生動(dong)(dong)植(zhi)物、微生物等。

生態保護

自80年云霧(wu)山(shan)草(cao)(cao)原(yuan)自然保(bao)護區自然風(feng)光代(dai)中(zhong)期于日本、美國(guo)、德國(guo)等生態(tai)學(xue)、土壤學(xue)和生物多樣性等方面(mian)的(de)科(ke)(ke)學(xue)家(jia)(jia)開展(zhan)了合作研究(jiu)(jiu)，目前已成(cheng)為(wei)中(zhong)國(guo)科(ke)(ke)學(xue)院(yuan)水(shui)利部水(shui)土保(bao)持研究(jiu)(jiu)所、西北農林(lin)科(ke)(ke)技大(da)學(xue)、蘭州大(da)學(xue)、寧(ning)夏大(da)學(xue)草(cao)(cao)業(ye)科(ke)(ke)學(xue)研究(jiu)(jiu)與研究(jiu)(jiu)生培養、農業(ye)部狐貍野性化(hua)(hua)馴養和國(guo)家(jia)(jia)林(lin)業(ye)局(ju)退化(hua)(hua)生態(tai)系(xi)統定位監(jian)測基(ji)地及全球氣候變化(hua)(hua)定位監(jian)測點，經(jing)過近(jin)30年的(de)封禁和草(cao)(cao)原(yuan)生態(tai)系(xi)統定位監(jian)測研究(jiu)(jiu)，生態(tai)經(jing)濟社會效益顯著，已成(cheng)為(wei)我國(guo)西部草(cao)(cao)原(yuan)植(zhi)被(bei)恢復與草(cao)(cao)原(yuan)自然修復的(de)一個成(cheng)功典范，為(wei)國(guo)家(jia)(jia)退耕還林(lin)草(cao)(cao)與地方封山(shan)禁牧工程的(de)實施提供了重要科(ke)(ke)學(xue)依據。

天然草地自然修復成效顯著

20世(shi)紀(ji)80年(nian)(nian)代初(chu)(chu)期，在(zai)(zai)區(qu)(qu)域考察的(de)(de)基礎上(shang)，我們(men)提(ti)(ti)出(chu)并(bing)在(zai)(zai)我國西部寧夏固原(yuan)云霧山(shan)建立(li)了(le)最早的(de)(de)典型草(cao)原(yuan)自(zi)(zi)然(ran)保(bao)(bao)護(hu)區(qu)(qu)，封(feng)(feng)(feng)(feng)禁(jin)(jin)(jin)保(bao)(bao)護(hu)面積由(you)0.23萬hm已擴大(da)(da)到(dao)(dao)1 萬hm。通過近30年(nian)(nian)封(feng)(feng)(feng)(feng)禁(jin)(jin)(jin)定位試(shi)驗，根據草(cao)地(di)(di)(di)(di)退化(hua)程度(du)(du)(du)采(cai)取封(feng)(feng)(feng)(feng)禁(jin)(jin)(jin)、改良、補播等草(cao)地(di)(di)(di)(di)建設技術途徑(jing)，使退化(hua)草(cao)地(di)(di)(di)(di)植(zhi)被(bei)種(zhong)(zhong)(zhong)類(lei)成(cheng)分(fen)(fen)、牧草(cao)生(sheng)長發(fa)育和(he)(he)草(cao)地(di)(di)(di)(di)生(sheng)境條件得到(dao)(dao)了(le)全面改善(shan)，草(cao)地(di)(di)(di)(di)生(sheng)產力有了(le)很大(da)(da)提(ti)(ti)高，草(cao)群(qun)種(zhong)(zhong)(zhong)類(lei)成(cheng)分(fen)(fen)發(fa)生(sheng)了(le)顯(xian)著(zhu)變化(hua)。封(feng)(feng)(feng)(feng)禁(jin)(jin)(jin)初(chu)(chu)期，草(cao)原(yuan)植(zhi)物(wu)(wu)(wu)(wu)(wu)僅為(wei)(wei)53種(zhong)(zhong)(zhong)，其中(zhong)(zhong)灌(guan)(guan)木(mu)和(he)(he)半灌(guan)(guan)木(mu)占(zhan)8%，草(cao)本占(zhan)92%，多(duo)(duo)數(shu)以旱生(sheng)植(zhi)物(wu)(wu)(wu)(wu)(wu)組成(cheng)，物(wu)(wu)(wu)(wu)(wu)種(zhong)(zhong)(zhong)密(mi)度(du)(du)(du)平均為(wei)(wei)5種(zhong)(zhong)(zhong)/m。隨封(feng)(feng)(feng)(feng)禁(jin)(jin)(jin)期延(yan)長物(wu)(wu)(wu)(wu)(wu)種(zhong)(zhong)(zhong)密(mi)度(du)(du)(du)逐(zhu)漸增加(jia)(jia)(jia)，封(feng)(feng)(feng)(feng)禁(jin)(jin)(jin)的(de)(de)第(di)(di)15年(nian)(nian)(1996年(nian)(nian))，物(wu)(wu)(wu)(wu)(wu)種(zhong)(zhong)(zhong)密(mi)度(du)(du)(du)達(da)到(dao)(dao)了(le)峰值，平均為(wei)(wei)33種(zhong)(zhong)(zhong)/m，是未封(feng)(feng)(feng)(feng)禁(jin)(jin)(jin)的(de)(de)3.1倍，草(cao)地(di)(di)(di)(di)群(qun)落(luo)物(wu)(wu)(wu)(wu)(wu)種(zhong)(zhong)(zhong)種(zhong)(zhong)(zhong)數(shu)達(da)到(dao)(dao)186種(zhong)(zhong)(zhong)，是未封(feng)(feng)(feng)(feng)禁(jin)(jin)(jin)的(de)(de)3.5倍，其中(zhong)(zhong)灌(guan)(guan)木(mu)和(he)(he)半灌(guan)(guan)木(mu)占(zhan)12%，草(cao)本占(zhan)88%，多(duo)(duo)數(shu)以中(zhong)(zhong)生(sheng)和(he)(he)中(zhong)(zhong)旱生(sheng)植(zhi)物(wu)(wu)(wu)(wu)(wu)組成(cheng)，并(bing)出(chu)現(xian)(xian)大(da)(da)量森林草(cao)原(yuan)地(di)(di)(di)(di)帶的(de)(de)灌(guan)(guan)木(mu)和(he)(he)草(cao)本植(zhi)物(wu)(wu)(wu)(wu)(wu)種(zhong)(zhong)(zhong)。草(cao)地(di)(di)(di)(di)覆蓋度(du)(du)(du)由(you)35%提(ti)(ti)高到(dao)(dao)95%，生(sheng)物(wu)(wu)(wu)(wu)(wu)量由(you)750提(ti)(ti)高到(dao)(dao)7560kg/hm。特別是在(zai)(zai)1986和(he)(he)1991年(nian)(nian)降雨量274.8mm和(he)(he)259.7mm的(de)(de)大(da)(da)旱年(nian)(nian)份，寧夏固原(yuan)2/3的(de)(de)地(di)(di)(di)(di)方由(you)于干(gan)旱缺草(cao)造(zao)成(cheng)60%~70%牲(sheng)畜死(si)亡，但(dan)封(feng)(feng)(feng)(feng)禁(jin)(jin)(jin)保(bao)(bao)護(hu)和(he)(he)改良草(cao)地(di)(di)(di)(di)周圍的(de)(de)鄉村(cun)5.0~6.0萬頭牲(sheng)畜得到(dao)(dao)了(le)挽救，直接減少(shao)經濟損失500萬元(yuan)，充分(fen)(fen)發(fa)揮了(le)"自(zi)(zi)然(ran)保(bao)(bao)護(hu)區(qu)(qu)"和(he)(he)改良草(cao)地(di)(di)(di)(di)的(de)(de)顯(xian)著(zhu)作用(yong)，保(bao)(bao)護(hu)區(qu)(qu)生(sheng)態、經濟、社會效益顯(xian)著(zhu)，受(shou)到(dao)(dao)了(le)各級政(zheng)府及群(qun)眾的(de)(de)一(yi)致贊揚，得到(dao)(dao)了(le)地(di)(di)(di)(di)方政(zheng)府表彰和(he)(he)獎勵。但(dan)封(feng)(feng)(feng)(feng)禁(jin)(jin)(jin)15年(nian)(nian)后隨封(feng)(feng)(feng)(feng)禁(jin)(jin)(jin)時間(jian)的(de)(de)延(yan)長，物(wu)(wu)(wu)(wu)(wu)種(zhong)(zhong)(zhong)密(mi)度(du)(du)(du)趨于下(xia)降，第(di)(di)24-28年(nian)(nian)(2008年(nian)(nian))物(wu)(wu)(wu)(wu)(wu)種(zhong)(zhong)(zhong)密(mi)度(du)(du)(du)僅為(wei)(wei)19.1種(zhong)(zhong)(zhong)/m。封(feng)(feng)(feng)(feng)禁(jin)(jin)(jin)期過長因(yin)枯草(cao)層(ceng)加(jia)(jia)(jia)厚而影響草(cao)地(di)(di)(di)(di)自(zi)(zi)然(ran)更(geng)新(xin)與物(wu)(wu)(wu)(wu)(wu)種(zhong)(zhong)(zhong)多(duo)(duo)樣性增加(jia)(jia)(jia)。草(cao)地(di)(di)(di)(di)土壤種(zhong)(zhong)(zhong)子(zi)庫研究表明，云霧山(shan)草(cao)地(di)(di)(di)(di)土壤種(zhong)(zhong)(zhong)子(zi)庫在(zai)(zai)空間(jian)分(fen)(fen)布上(shang)呈現(xian)(xian)一(yi)定的(de)(de)規律(lv)性，種(zhong)(zhong)(zhong)子(zi)密(mi)度(du)(du)(du)在(zai)(zai)垂直分(fen)(fen)布上(shang)呈現(xian)(xian)出(chu)由(you)表層(ceng)土壤向深層(ceng)逐(zhu)層(ceng)減少(shao)的(de)(de)變化(hua)規律(lv)，水(shui)平分(fen)(fen)布上(shang)變化(hua)規律(lv)為(wei)(wei):封(feng)(feng)(feng)(feng)禁(jin)(jin)(jin)>放牧;陰坡>陽坡;下(xia)坡>中(zhong)(zhong)坡>上(shang)坡，這些均是影響群(qun)落(luo)物(wu)(wu)(wu)(wu)(wu)種(zhong)(zhong)(zhong)多(duo)(duo)樣性增加(jia)(jia)(jia)和(he)(he)草(cao)地(di)(di)(di)(di)繁殖(zhi)更(geng)新(xin)的(de)(de)關鍵(jian)問題。

通過近30年(nian)(nian)的(de)自(zi)然封禁(jin)試(shi)驗，明確提出草(cao)(cao)(cao)(cao)地(di)(di)(di)(di)(di)恢復的(de)適(shi)宜(yi)封禁(jin)期:在(zai)(zai)(zai)半干旱(han)區(qu)森(sen)林草(cao)(cao)(cao)(cao)原(yuan)地(di)(di)(di)(di)(di)帶，草(cao)(cao)(cao)(cao)甸(dian)植(zhi)被的(de)適(shi)宜(yi)恢復期為3~5年(nian)(nian)，方(fang)可(ke)進(jin)行(xing)合理(li)(li)的(de)放(fang)牧(mu)或(huo)刈(yi)割利(li)(li)用，對利(li)(li)用過度(du)退化嚴重(zhong)(zhong)的(de)草(cao)(cao)(cao)(cao)甸(dian)植(zhi)被在(zai)(zai)(zai)平(ping)水年(nian)(nian)需(xu)要封禁(jin)8~12年(nian)(nian);在(zai)(zai)(zai)典型草(cao)(cao)(cao)(cao)原(yuan)地(di)(di)(di)(di)(di)帶，草(cao)(cao)(cao)(cao)地(di)(di)(di)(di)(di)植(zhi)被適(shi)宜(yi)恢復期為5~8年(nian)(nian)，方(fang)可(ke)進(jin)行(xing)合理(li)(li)刈(yi)割和放(fang)牧(mu)利(li)(li)用，退化嚴重(zhong)(zhong)的(de)草(cao)(cao)(cao)(cao)地(di)(di)(di)(di)(di)植(zhi)被在(zai)(zai)(zai)平(ping)水年(nian)(nian)約需(xu)封禁(jin)10~15年(nian)(nian);在(zai)(zai)(zai)荒漠(mo)草(cao)(cao)(cao)(cao)原(yuan)地(di)(di)(di)(di)(di)帶，草(cao)(cao)(cao)(cao)地(di)(di)(di)(di)(di)植(zhi)被適(shi)宜(yi)恢復期為10~12年(nian)(nian)，方(fang)可(ke)進(jin)行(xing)合理(li)(li)的(de)刈(yi)割和放(fang)牧(mu)利(li)(li)用，退化嚴重(zhong)(zhong)草(cao)(cao)(cao)(cao)地(di)(di)(di)(di)(di)在(zai)(zai)(zai)平(ping)水年(nian)(nian)約需(xu)封禁(jin)15~20年(nian)(nian)。這一結論通過多年(nian)(nian)的(de)試(shi)驗驗證，已(yi)建立了示范樣板，為同類型區(qu)天然植(zhi)被恢復利(li)(li)用提供了重(zhong)(zhong)要科學依(yi)據。

封禁草地自然演替過程與規律

通過近(jin)30年的(de)(de)(de)(de)(de)封(feng)(feng)(feng)禁(jin)(jin)試驗(yan)，首次劃(hua)分(fen)了(le)(le)草(cao)(cao)地(di)(di)植(zhi)被(bei)恢復與時(shi)序演(yan)替(ti)過程，分(fen)為五(wu)個(ge)階(jie)(jie)(jie)段(duan)(duan)(duan)(duan):第一階(jie)(jie)(jie)段(duan)(duan)(duan)(duan)為種(zhong)(zhong)群(qun)(qun)(qun)持續增長(chang)(chang)聚集階(jie)(jie)(jie)段(duan)(duan)(duan)(duan)，即(ji)在(zai)封(feng)(feng)(feng)禁(jin)(jin)的(de)(de)(de)(de)(de)1~3年內以本(ben)(ben)氏針(zhen)(zhen)(zhen)(zhen)茅(mao)(mao)鄉土種(zhong)(zhong)為主的(de)(de)(de)(de)(de)建(jian)群(qun)(qun)(qun)種(zhong)(zhong)與其它優(you)勢種(zhong)(zhong)、伴生種(zhong)(zhong)和偶見種(zhong)(zhong)不(bu)斷適(shi)(shi)應(ying)新的(de)(de)(de)(de)(de)生境，各項生長(chang)(chang)指標(biao)穩定增長(chang)(chang);第二(er)階(jie)(jie)(jie)段(duan)(duan)(duan)(duan)為種(zhong)(zhong)間(jian)激(ji)烈(lie)(lie)競(jing)爭(zheng)階(jie)(jie)(jie)段(duan)(duan)(duan)(duan)，也是封(feng)(feng)(feng)禁(jin)(jin)的(de)(de)(de)(de)(de)第4~9年，植(zhi)物數(shu)量(liang)(liang)(liang)大(da)幅度增長(chang)(chang)，并適(shi)(shi)應(ying)了(le)(le)新的(de)(de)(de)(de)(de)生境，且(qie)相互(hu)展(zhan)開了(le)(le)激(ji)烈(lie)(lie)的(de)(de)(de)(de)(de)種(zhong)(zhong)間(jian)競(jing)爭(zheng)與自(zi)然選(xuan)擇(ze);第三階(jie)(jie)(jie)段(duan)(duan)(duan)(duan)為建(jian)群(qun)(qun)(qun)種(zhong)(zhong)加速恢復演(yan)替(ti)階(jie)(jie)(jie)段(duan)(duan)(duan)(duan)，即(ji)封(feng)(feng)(feng)禁(jin)(jin)的(de)(de)(de)(de)(de)10~15年，植(zhi)物在(zai)激(ji)烈(lie)(lie)的(de)(de)(de)(de)(de)種(zhong)(zhong)間(jian)競(jing)爭(zheng)中(zhong)"物競(jing)天擇(ze)、適(shi)(shi)者(zhe)生存(cun)"，本(ben)(ben)氏針(zhen)(zhen)(zhen)(zhen)茅(mao)(mao)形成明顯(xian)建(jian)群(qun)(qun)(qun)種(zhong)(zhong)，并不(bu)斷加速種(zhong)(zhong)群(qun)(qun)(qun)自(zi)身的(de)(de)(de)(de)(de)恢復與擴(kuo)展(zhan), 且(qie)已(yi)達(da)到(dao)"亞頂(ding)極";第四階(jie)(jie)(jie)段(duan)(duan)(duan)(duan)為建(jian)群(qun)(qun)(qun)種(zhong)(zhong)的(de)(de)(de)(de)(de)定居生長(chang)(chang)階(jie)(jie)(jie)段(duan)(duan)(duan)(duan)，封(feng)(feng)(feng)禁(jin)(jin)的(de)(de)(de)(de)(de)16~21年本(ben)(ben)氏針(zhen)(zhen)(zhen)(zhen)茅(mao)(mao)種(zhong)(zhong)群(qun)(qun)(qun)個(ge)體數(shu)量(liang)(liang)(liang)的(de)(de)(de)(de)(de)變化基(ji)本(ben)(ben)穩定在(zai)19株(zhu)/m，占群(qun)(qun)(qun)落(luo)總(zong)數(shu)的(de)(de)(de)(de)(de)90.5%，已(yi)達(da)到(dao)"亞頂(ding)極";第五(wu)階(jie)(jie)(jie)段(duan)(duan)(duan)(duan)22~28年本(ben)(ben)氏針(zhen)(zhen)(zhen)(zhen)茅(mao)(mao)種(zhong)(zhong)群(qun)(qun)(qun)的(de)(de)(de)(de)(de)生長(chang)(chang)繁(fan)殖受(shou)枯草(cao)(cao)層(ceng)的(de)(de)(de)(de)(de)影響，個(ge)體數(shu)量(liang)(liang)(liang)急劇(ju)下降，優(you)勢種(zhong)(zhong)大(da)針(zhen)(zhen)(zhen)(zhen)茅(mao)(mao)種(zhong)(zhong)群(qun)(qun)(qun)的(de)(de)(de)(de)(de)數(shu)量(liang)(liang)(liang)巨(ju)增，密度為16~26株(zhu)/m，有替(ti)代本(ben)(ben)氏針(zhen)(zhen)(zhen)(zhen)茅(mao)(mao)的(de)(de)(de)(de)(de)趨勢。同(tong)時(shi)在(zai)草(cao)(cao)原群(qun)(qun)(qun)落(luo)生長(chang)(chang)的(de)(de)(de)(de)(de)溝道還出現大(da)量(liang)(liang)(liang)的(de)(de)(de)(de)(de)中(zhong)生灌木，多(duo)為森(sen)林(lin)草(cao)(cao)原區成分(fen)，已(yi)由草(cao)(cao)原群(qun)(qun)(qun)落(luo)坡下部的(de)(de)(de)(de)(de)陰(yin)(yin)坡或半陰(yin)(yin)坡以片狀(zhuang)分(fen)布，逐漸向(xiang)草(cao)(cao)原腹地(di)(di)呈零星(xing)狀(zhuang)入侵，使(shi)草(cao)(cao)原群(qun)(qun)(qun)落(luo)的(de)(de)(de)(de)(de)演(yan)替(ti)進(jin)入了(le)(le)一個(ge)重要的(de)(de)(de)(de)(de)階(jie)(jie)(jie)段(duan)(duan)(duan)(duan)，形成了(le)(le)一個(ge)明顯(xian)的(de)(de)(de)(de)(de)拐點，直到(dao)封(feng)(feng)(feng)禁(jin)(jin)的(de)(de)(de)(de)(de)第28年物種(zhong)(zhong)豐富度仍保持在(zai)148種(zhong)(zhong)，具有典型草(cao)(cao)原群(qun)(qun)(qun)落(luo)向(xiang)森(sen)林(lin)草(cao)(cao)原群(qun)(qun)(qun)落(luo)類型演(yan)替(ti)發(fa)展(zhan)的(de)(de)(de)(de)(de)趨勢。

封禁草地適度刈割利用技術

在黃土高(gao)原典型草(cao)(cao)原地(di)(di)帶，通過不同刈割強度(du)試驗，表明適(shi)度(du)刈割可(ke)使草(cao)(cao)地(di)(di)保持(chi)較高(gao)的物種(zhong)多樣性和(he)生產力(li)，并能促進草(cao)(cao)地(di)(di)物質平衡及良性循(xun)環，為封禁草(cao)(cao)地(di)(di)的合理(li)刈割利(li)用提供了重要依(yi)據(ju)。