黄土高原旱地土壤质量评价指标研究_罗珠珠

Abstract
Based on long-term field experiments at Dingxi in the western Loess Plateau, the effects of different agricultural meas-
ures on soil quality were studied using an integrated assessment model. A total of 6 agricultural measures with 2 tillage systems and 3 ground-cover forms were used. The agricultural measured included conventional tillage (T), no-tillage (NT), conventional tillage with straw incorporation (TS), no-tillage with straw mulching (NTS), conventional tillage with plastic-film mulch (TP) and no-tillage with plastic-film mulch (NTP). The experiment was conducted in two rotation sequences. Sequence 1 started with pea followed by spring wheat (P→W) whereas sequence 2 started with spring wheat followed by field pea (W→P). The results showed that soil quality evaluation with integrated-weighted and addition-multiplication methods reasonably reflected actual soil conditions, and the effect of tillage variations on soil quality. The 8 most sensitive indicators were selected from a total of 29 assessment indictors vial discriminative analysis. The selected indicators were used to evaluate soil physical quality, fertility, health and land productivity in the
中国生态农业学报
2012 年 2 月
第 20 卷
第2期
Chinese Journal of Eco-Agriculture, Feb. 2012, 20(2): 127 137
DOI: 10.3724/SP.J.1011.2012.00127
黄土高原旱地土壤质量评价指标研究*
罗珠珠 1,2 黄高宝 2** 蔡立群 1,2
土质绵软, 土层深厚, 质地均匀, 贮水性能良好; 0~200 cm 土层土壤容重平均为 1.17 g·cm3, 凋萎含 水率 7.3%, 饱和含水率 21.9%。 1.2 研究方法 1.2.1 试验设计 试验共设传统耕作 (T) 、免耕 (NT) 、传统耕作秸 秆还田 (TS) 、免耕秸秆覆盖 (NTS) 、传统耕作地膜 覆盖 (TP)、免耕地膜覆盖 (NTP) 6 个处理 , 具体耕作 方法见表 1。结合小麦豌豆的年际轮作 , 为加快研 究 进 程 , 研 究 设 计 了 小 麦 → 豌 豆 (2002 年 小 麦 → 2003 年豌豆 →2004 年小麦 →2005 年豌豆 →2006 年 小麦 →2007 年豌豆 , 简称 W→P→W→P→W→P)和 豌豆 →小麦 (2002 年豌豆 →2003 年小麦 →2004 年豌 豆 →2005 年小麦 →2006 年豌豆 →2007 年小麦 , 简称 P→W→P→W→P→W)2 个轮作序列 , 4 次重复 , 共 48 个小区 , 小区面积 4 m×20 m, 随机区组排列。 供 试 作 物 春 小 麦 为 “ 定 西 35”, 播 种 量 187.5 T、 kg·hm2; 豌豆为 “绿农 1 号 ”, 播种量 100 kg·hm2。 NT、TS、NTS 处理用中国农业大学研制的免耕播种 机播种 , 春小麦行距 20 cm, 豌豆行距 24 cm, 播深 均为 7 cm。春小麦播期为 3 月中旬 , 豌豆为同年 3 月下旬。小麦各处理均施 N 105 kg·hm2、 P2O5 105 kg·hm2 ( 尿 素 + 二 铵 ); 豌 豆 各 处 理 均 施 N 20 kg·hm2、 P2O5 105 kg·hm2 (二铵 +过磷酸钙 ), 所有 肥料都作为基肥在播种时同时施入。 1.2.2 采样与试验分析 春小麦生育期为 2007 年 3 月中旬至 8 月中旬 , 豌豆生育期为 2007 年 4 月上旬至 7 月中旬。 作物收 获后 (2007 年 8 月中旬 ), 分 0~5 cm、 5~10 cm、 10~30 cm 3 个层次采集样品。 各小区随机取 5 个点 , 剔除石块、植物残根等杂物 , 混合装袋带回实验室 , 样品经风干后研磨、过筛分装以备测定土壤物理、 化学和生物学性状。土壤容重、孔隙度、田间持水 量、饱和含水量用环刀法测定 [13] , 土壤团粒结构用 湿筛 法测定 [ 1 4 ] , 土壤饱和导 水率用圆盘 渗透仪法 测定 [15] , 土壤坚实度用 Agridry Rimik Pty Ltd 生产 的土壤锥形紧实度仪 (CP20) 测定 , 土壤水分用烘干 法和中子仪测定 , 土壤温度用曲管地温计测定 ( 每 天 14:00) 。土壤有机质和养分含量采用常规方法测 定 [16]。土壤过氧化氢酶活性采用高锰酸钾滴定法测 定 [17] , 土壤脲酶活性采用靛酚蓝比色法测定 [17] , 土 壤碱性磷酸酶活性采用磷酸苯二钠比色法 [18] , 土壤 蔗糖酶活性采用 3,5- 二硝基水杨酸比色法测定 [19] ,
中图分类号 : S157.4+2; S158.2
文章编号 : 1671-3990(2012)02-0127-11
Assessment indicators of soil quality in rain-fed areas of the Loess Plateau
LUO Zhu-Zhu1,2, HUANG Gao-Bao2, CAI Li-Qun1,2, ZHANG Ren-Zhi1,2, LI Ling-Ling2, XIE Jun-Hong2
1
1.1
材料与方法
研究区概况 试验设在陇中黄土高原半干旱丘陵沟壑区的定 西市安定区李家堡镇麻子川村。试区属中温带半干 旱区, 平均海拔 2 000 m, 年均太阳辐射 592 596 J·cm2, 日照时数 2 476.6 h, 年均气温 6.4 ℃ , ≥ 0 ℃积温 2 933.5 ℃ , ≥ 10 ℃积温 2 239.1 ℃, 无霜期 140 d。多 年平均降水 390.9 mm, 年蒸发量 1 531 mm, 干燥度 2.53, 80%保证率的降水量为 365 mm, 变异系数为 24.3%, 为典型的雨养农业区。 土壤为典型的黄绵土 ,
(1. Faculty of Resources and Environmental Sciences, Gansu Agricultural University, Lanzhou 730070, China; 2. Gansu Provincial Key Laboratory for Arid-land Crop Sciences; Faculty of Agronomy, Gansu Agricultural University, Lanzhou 730070, China)
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中国生态农业学报 2012
第 20 卷
semi-arid areas of the Loess Plateau. These 8 indicators included soil aggregates, organic matter, total nitrogen, available nitrogen, invertase activity, grain yield, net income and output/input ratio. Based on the 29 indicators, the order of soil quality index (SQI) ranked from high to low was NTS, TS, NTP, NT, TP and T in both rotation sequences. Again based on the 8 indicators, the orders of SQI ranked from high to low were NTS, TS, NTP, NT, T and TP in the P→W rotation sequence, and NTS, TS, NT, NTP, T and TP in the W→P rotation sequence. The results of the 2 assessment systems were similar and highly correlated. This indicated that the 8 indicators were sufficiently representative of the soil conditions in the western Loess Plateau. Key words Loess Plateau, Tillage system, Wheat/pea rotation, Soil quality, Soil health, Assessment indicator (Received Apr. 28, 2011; accepted Aug. 31, 2011)