怎樣給鹽堿地(di)小麥平衡施(shi)肥

大部分鹽漬(zi)化土壤中，土壤有機質含量低，礦(kuang)質養分不(bu)均衡(heng)，微量元素缺(que)乏，作(zuo)物所必需(xu)的礦(kuang)質元素因土壤PH值較高而形(xing)成沉淀難以(yi)被(bei)作(zuo)物吸(xi)收利(li)用，從而導致(zhi)農作(zuo)物營(ying)養缺(que)乏。鹽堿(jian)地小(xiao)麥要(yao)高產，施肥是關鍵。主要(yao)掌握以(yi)下(xia)原則：

一、堅持以有機肥為主

農(nong)諺說(shuo)：“堿(jian)大吃苗，肥大吃堿(jian)。”這里所說(shuo)的(de)(de)肥即指有(you)機(ji)肥料，給鹽(yan)(yan)堿(jian)地增施有(you)機(ji)肥料，能(neng)增加土壤中(zhong)有(you)機(ji)質含量，使(shi)農(nong)作物(wu)(wu)在整個(ge)生育過程中(zhong)得到全面營養，而且提高土壤保(bao)肥能(neng)力(li)和對酸堿(jian)及有(you)害離子的(de)(de)緩(huan)沖能(neng)力(li)，降低土壤中(zhong)鹽(yan)(yan)分與PH值，減(jian)輕鹽(yan)(yan)堿(jian)對農(nong)作物(wu)(wu)的(de)(de)為害，促進(jin)土壤熟化(hua)。一(yi)般來說(shuo)，每(mei)畝鹽(yan)(yan)堿(jian)地應施有(you)機(ji)肥3～4立(li)方米(mi)，并要堅持每(mei)年秸稈(gan)還田。在當前有(you)機(ji)肥料不足的(de)(de)情況下，種植綠(lv)肥是解(jie)決(jue)脫鹽(yan)(yan)問題的(de)(de)重要途徑(jing)。

二、合理選用化肥種類

化肥(fei)(fei)大(da)多數(shu)是鹽類，有(you)酸(suan)性(xing)(xing)(xing)(xing)、堿(jian)(jian)性(xing)(xing)(xing)(xing)、中(zhong)性(xing)(xing)(xing)(xing)之分。酸(suan)性(xing)(xing)(xing)(xing)、中(zhong)性(xing)(xing)(xing)(xing)化肥(fei)(fei)可(ke)以在(zai)(zai)(zai)鹽堿(jian)(jian)地(di)上(shang)(shang)施(shi)(shi)用(yong)(yong)。而堿(jian)(jian)性(xing)(xing)(xing)(xing)肥(fei)(fei)料則應避免在(zai)(zai)(zai)鹽堿(jian)(jian)地(di)上(shang)(shang)施(shi)(shi)用(yong)(yong)。如尿素、碳酸(suan)氫銨(an)(an)(an)、硝酸(suan)銨(an)(an)(an)等在(zai)(zai)(zai)土壤(rang)中(zhong)不殘(can)留任何雜質，不會(hui)增加土壤(rang)中(zhong)的(de)鹽分和(he)堿(jian)(jian)性(xing)(xing)(xing)(xing)，適宜在(zai)(zai)(zai)鹽堿(jian)(jian)地(di)上(shang)(shang)施(shi)(shi)用(yong)(yong);硫(liu)酸(suan)銨(an)(an)(an)是生(sheng)理酸(suan)性(xing)(xing)(xing)(xing)肥(fei)(fei)料，其中(zhong)的(de)銨(an)(an)(an)被小麥(mai)吸收后，殘(can)留的(de)硫(liu)酸(suan)根可(ke)以降(jiang)低鹽堿(jian)(jian)的(de)堿(jian)(jian)性(xing)(xing)(xing)(xing)，也(ye)適宜施(shi)(shi)用(yong)(yong);草(cao)木灰等堿(jian)(jian)性(xing)(xing)(xing)(xing)肥(fei)(fei)料，就不適宜在(zai)(zai)(zai)鹽堿(jian)(jian)地(di)上(shang)(shang)施(shi)(shi)用(yong)(yong);給鹽堿(jian)(jian)地(di)小麥(mai)施(shi)(shi)用(yong)(yong)磷(lin)(lin)(lin)肥(fei)(fei)時，應選(xuan)用(yong)(yong)過磷(lin)(lin)(lin)酸(suan)鈣(gai)。而鈣(gai)鎂磷(lin)(lin)(lin)肥(fei)(fei)是堿(jian)(jian)性(xing)(xing)(xing)(xing)肥(fei)(fei)料，在(zai)(zai)(zai)鹽堿(jian)(jian)地(di)上(shang)(shang)施(shi)(shi)用(yong)(yong)，不僅沒(mei)有(you)效果，還會(hui)導致土壤(rang)堿(jian)(jian)性(xing)(xing)(xing)(xing)加重。

三、注意配合施用有機肥料

這樣既可以(yi)補充多種營養，又有(you)利于降(jiang)低(di)土(tu)壤溶(rong)液(ye)濃(nong)度(du)，減輕(qing)由于施(shi)(shi)用(yong)化(hua)肥而引(yin)起鹽(yan)堿為害。施(shi)(shi)肥要注意多次(ci)少量(liang)施(shi)(shi)用(yong)，以(yi)免土(tu)壤溶(rong)液(ye)濃(nong)度(du)驟(zou)然過高，影響(xiang)小麥吸收和(he)生長(chang)。銨態氮(dan)肥在鹽(yan)堿地(di)上施(shi)(shi)用(yong)易引(yin)起氨(an)的(de)揮(hui)發。因此，一定要深施(shi)(shi)埋嚴。鹽(yan)堿地(di)地(di)溫(wen)低(di)，微(wei)生物活動減弱，有(you)效磷釋放少，常表現缺磷，增(zeng)施(shi)(shi)磷肥可以(yi)顯著增(zeng)產，施(shi)(shi)肥方法是做底(di)肥深施(shi)(shi)。