怎(zen)樣(yang)給(gei)鹽堿(jian)地小麥平衡施肥

大部分鹽漬(zi)化土(tu)壤中(zhong)，土(tu)壤有機質(zhi)含量低，礦質(zhi)養分不(bu)均(jun)衡，微量元(yuan)素(su)缺乏，作物(wu)所(suo)必需的礦質(zhi)元(yuan)素(su)因土(tu)壤PH值較高而形成(cheng)沉淀難以被作物(wu)吸收(shou)利用，從而導致(zhi)農作物(wu)營養缺乏。鹽堿地(di)小麥要高產(chan)，施(shi)肥是關(guan)鍵。主要掌握以下原則：

一、堅持以有機肥為主

農(nong)諺說(shuo)：“堿(jian)大(da)吃苗(miao)，肥(fei)(fei)大(da)吃堿(jian)。”這里所說(shuo)的肥(fei)(fei)即指有機(ji)肥(fei)(fei)料，給鹽(yan)(yan)(yan)堿(jian)地(di)增施(shi)有機(ji)肥(fei)(fei)料，能增加土(tu)壤(rang)中有機(ji)質含(han)量，使農(nong)作(zuo)物(wu)在(zai)整個(ge)生育過程中得到全(quan)面營養，而且(qie)提高土(tu)壤(rang)保肥(fei)(fei)能力(li)和對(dui)酸堿(jian)及有害離子的緩沖能力(li)，降低土(tu)壤(rang)中鹽(yan)(yan)(yan)分與(yu)PH值(zhi)，減輕鹽(yan)(yan)(yan)堿(jian)對(dui)農(nong)作(zuo)物(wu)的為害，促進土(tu)壤(rang)熟化。一般來說(shuo)，每畝鹽(yan)(yan)(yan)堿(jian)地(di)應施(shi)有機(ji)肥(fei)(fei)3～4立方米，并要堅持每年秸稈(gan)還田。在(zai)當前(qian)有機(ji)肥(fei)(fei)料不足的情(qing)況下(xia)，種植綠肥(fei)(fei)是解決脫鹽(yan)(yan)(yan)問(wen)題的重要途徑。

二、合理選用化肥種類

化肥(fei)(fei)大(da)多數是(shi)(shi)鹽(yan)(yan)(yan)類(lei)，有酸(suan)性(xing)、堿(jian)(jian)(jian)(jian)(jian)(jian)性(xing)、中(zhong)性(xing)之分。酸(suan)性(xing)、中(zhong)性(xing)化肥(fei)(fei)可以(yi)在(zai)鹽(yan)(yan)(yan)堿(jian)(jian)(jian)(jian)(jian)(jian)地上(shang)施(shi)用。而堿(jian)(jian)(jian)(jian)(jian)(jian)性(xing)肥(fei)(fei)料(liao)則應(ying)避(bi)免在(zai)鹽(yan)(yan)(yan)堿(jian)(jian)(jian)(jian)(jian)(jian)地上(shang)施(shi)用。如尿素(su)、碳酸(suan)氫銨(an)(an)、硝酸(suan)銨(an)(an)等在(zai)土壤中(zhong)不殘留任何雜質，不會增加土壤中(zhong)的(de)(de)鹽(yan)(yan)(yan)分和堿(jian)(jian)(jian)(jian)(jian)(jian)性(xing)，適宜在(zai)鹽(yan)(yan)(yan)堿(jian)(jian)(jian)(jian)(jian)(jian)地上(shang)施(shi)用;硫酸(suan)銨(an)(an)是(shi)(shi)生理酸(suan)性(xing)肥(fei)(fei)料(liao)，其(qi)中(zhong)的(de)(de)銨(an)(an)被小麥吸(xi)收后，殘留的(de)(de)硫酸(suan)根可以(yi)降(jiang)低鹽(yan)(yan)(yan)堿(jian)(jian)(jian)(jian)(jian)(jian)的(de)(de)堿(jian)(jian)(jian)(jian)(jian)(jian)性(xing)，也(ye)適宜施(shi)用;草木灰等堿(jian)(jian)(jian)(jian)(jian)(jian)性(xing)肥(fei)(fei)料(liao)，就(jiu)不適宜在(zai)鹽(yan)(yan)(yan)堿(jian)(jian)(jian)(jian)(jian)(jian)地上(shang)施(shi)用;給鹽(yan)(yan)(yan)堿(jian)(jian)(jian)(jian)(jian)(jian)地小麥施(shi)用磷肥(fei)(fei)時，應(ying)選用過磷酸(suan)鈣(gai)。而鈣(gai)鎂(mei)磷肥(fei)(fei)是(shi)(shi)堿(jian)(jian)(jian)(jian)(jian)(jian)性(xing)肥(fei)(fei)料(liao)，在(zai)鹽(yan)(yan)(yan)堿(jian)(jian)(jian)(jian)(jian)(jian)地上(shang)施(shi)用，不僅沒有效果(guo)，還(huan)會導致土壤堿(jian)(jian)(jian)(jian)(jian)(jian)性(xing)加重。

三、注意配合施用有機肥料

這(zhe)樣(yang)既可(ke)以補充多種營養(yang)，又有利(li)于降(jiang)低土壤(rang)溶液(ye)濃度，減(jian)輕(qing)由于施(shi)(shi)用(yong)化肥而引(yin)起鹽堿為(wei)害。施(shi)(shi)肥要(yao)(yao)注意多次少(shao)量(liang)施(shi)(shi)用(yong)，以免土壤(rang)溶液(ye)濃度驟(zou)然過高(gao)，影響小麥吸收和生(sheng)長。銨(an)態氮肥在鹽堿地上施(shi)(shi)用(yong)易引(yin)起氨的(de)揮發。因此，一(yi)定要(yao)(yao)深(shen)施(shi)(shi)埋嚴。鹽堿地地溫低，微生(sheng)物活(huo)動減(jian)弱，有效磷釋放少(shao)，常(chang)表(biao)現缺(que)磷，增施(shi)(shi)磷肥可(ke)以顯著增產，施(shi)(shi)肥方法是做底肥深(shen)施(shi)(shi)。