摘 要

为探明城市污泥生物质炭对风沙土土壤酶及CO₂排放量的影响，采集土壤样品，通过向土壤中添加不同量（0,20,40和60t/ha）的污泥生物质炭进行室内培养，对风沙土土壤CO₂排放速率、累计排放量和土壤中脲酶、过氧化氢酶、转化酶及磷酸酶活性的动态变化进行了分析。结果表明:污泥生物质炭对土壤转化酶、过氧化氢酶、磷酸酶和脲酶活性的影响均表现为前期升高后期降低；在培养结束后，磷酸酶和过氧化氢酶的活性较培养初期降低；而转化酶和脲酶活性与培养初期相比差异不大。污泥生物质炭低施量能减少CO₂排放，而高施量增加CO₂排放。各处理中，施用NPK处理的CO₂日均排放量和累计排放量最高。该研究表明，污泥生质炭对土壤酶活性有影响，但因酶的种类不同，其影响也不同。低适量的污泥生物质炭可能促进土壤固碳。

关键词：脲酶;过氧化氢酶;转化酶;磷酸酶;CO₂通量

Effects of sewage sludge biochar on soil enzymes and CO₂ emissions in a sandy soil

ABSTRACT

In order to explore the effect of sewage sludge biochar on soil enzymes and CO₂ emissions in a sandy soil, soil samples were collected from 0-20cm and a laboratory incubation experiment was conducted by adding different amounts of sewage sludge biochar into the soil. The daily CO₂ emission rates, cumulative CO₂ emissions and activities of urease, catalase, invertase and phosphatase in the sandy soil were analyzed. The results showed that the activity of invertase, urease, catalase and phosphatase were significantly promoted by the addition of biochar in the first fewer days and then, the soil enzyme activities were decreased. Soil phosphatase catalase activities were lower at the end of incubation than those at the beginning; while no difference on soil invertase and urease activities when compared with those at the beginning of the incubation. Soil CO₂ emissions was decreased by B₂₀, when compared with ck; while B₆₀ increased soil CO₂ emissions. The highest CO₂ emissions were shown in NPK treatment. Sewage sluge biochar affect soil enzyme activities. But the effect was different. Lower amount of biochar addition might have the potential to increase soil carbon sequestration.

Key words: Urease;Catalase;Invertase;Phosphatase;CO₂ flux

目录

1.绪论 5

1.1国内外研究现状 5

1.2研究目的及意义 7

1.3研究区概况 7

2.研究内容及方法 9

2.1研究内容 9

2.1.1不同施量城市污泥生物质炭对风沙土土壤CO₂排放量的影响 9

2.2.2不同施量城市污泥生物质炭对风沙土土壤酶活性影响 9

2.2 研究方法 9

2.2.1试验材料 9

2.2.2采样 11

2.2.3培养试验方案设计 11

2.3数据处理 13

3结果与分析 13

3.1不同施量污泥生物质炭对土壤酶活性影响 13

3.1.1转化酶 13

3.1.2磷酸酶 14

3.1.3过氧化氢酶 14

3.1.4脲酶 15

3.2不同施量污泥生物质炭对风沙土土壤CO₂排放量的影响 16

4结论与讨论 17

4.1不同施量污泥生物质炭对土壤酶活性影响 17

4.2不同施量污泥生物质炭对风沙土土壤CO₂排放量的影响 18

致谢 19

参考文献 20

1.绪论

1.1国内外研究现状

随着世界人口的不断增长，人类与耕地的矛盾愈来愈加严重，联合国粮农组织指出，地球表面只有11%（约15亿hm²）的土地适合用于耕地，其余89%为非宜农土地（其中28%太干旱，23%存在化学问题，22%土层台前，10%太湿，剩余6%为永冻土）。另一方面，现有的15亿hm²耕地中，低产土壤占据了相当一部分的比重，且土地在不断的退化和丧失。受经济增长及气候变化等原因影响，全球粮食安全问题日渐突出，已引起了社会各界的广泛关注^[1]。

风沙土在中国面积分布较大，仅华北平原风沙土分布面积达到25,800 km²。风沙土质地较轻，漏水漏肥现象严重，土壤肥力较低。提高风沙土土壤肥力，增加粮食产量，对保障国家粮食安全至关重要。根据全国第二次土壤普查结果结合《河南土壤》及土壤类型分布图，豫东平原黄泛区主要土壤类型为潮土、风沙土及褐土，三种土类面积占研究区总面积的 97.34%。风沙土约占该区土壤总面积的17.89%，仅次于潮土的73.24%，是黄河冲积物在风力搬运和堆积作用下形成的沙丘、砂垄和沙岗上发育形成的土壤，土壤性状差，坡面发育微弱。

从现有的研究可以总结出豫东平原黄泛区风沙型中低产田土壤存在的5大农业相关土壤特性：