【作者】 李登峰；

【导师】 张放；

【作者基本信息】 浙江大学 ， 果树学， 2004， 硕士

【摘要】 果园间作是一种传统的土地利用方式和生产技术，一直以来，果园间作也是三峡库区丰富城乡农产品市场，繁荣城乡经济的主要来源。它不但充分利用了自然资源，提高了资源的利用效率，而且具有良好的生态、经济效益。但传统的间作模式水土流失较为严重、经济效益低下，随着三峡工程的建成，大批沿江优质果园将被淹没或已经被淹没，传统的果园间作模式无法满足现代果园的生产要求，特别是大批新开发的坡耕地幼龄果园。我们在分析库区果园生产现状的基础上，引进了浙江北部山区一种新兴的果园间作模式梨-旱稻，与库区现存较多的其它几种果园间作模式进行了水土保持、生态、经济效益方面的研究，并对这几种模式进行了评价。 本研究采取实地调查(结合当地统计资料)与野外实验相结合的研究办法，在分析库区果园生产现状的基础上，对幼龄梨园梨-旱稻、梨-红薯、梨-花生、裸地梨园四种间作模式进行了比较分析，得出的结论如下： 1、三峡工程的建设，对库区果树业的发展提供了一个巨大的发展机遇，应该充分利用这一机遇逐步改变库区果树的分布，对大量新开发建设的果园而言，树种的搭配和品种的安排应该科学合理，库区果园内的树种选择，我们应该选择具有较大发展潜力的果树作为果园间作的主栽树种，像梨、李等落叶果树在库区的单产平均值、产投比、平均产值均较高，而波动性较大，具有很大的发展潜力，在新开发建设的果园应优先考虑发展这些品种，据此，我们引进推广了幼龄梨园梨-旱稻间作模式。 2、我们发现，每10 mm降雨在不同处理下的径流深度(及径流系数)从小到大排列顺序依次为：梨-旱稻，1.60mm(0.160)＜梨-红薯，1.89mm(0.189)＜梨-花生，2.17mm(0.217)＜裸地梨园，3.26mm(0.326)。在库区实地的研究结果表明，在新开垦的坡耕地幼龄果园里，若果树间地表无其它作物覆盖时，有32.6％以上的降雨以地表径流的形式流失；在幼龄果树间种植其它根系发达型作物，尤其在果树株行间保留旱稻，能够显著降低径流系数，减少降水流失。 3、总水土流失量的测定结果表明，在3次累计降雨为100.86mm的降雨过程中，3种处理的总水土流失量分别为：梨-红薯处理188.981t／hm~2、梨-花生处理217.48 t／hm~2、梨-旱稻处理160.857 t／hm~2、裸地梨园为328.814 t／hm~2，其中梨-旱稻处理最低，裸地梨园的最高。4个处理在3场降雨累计情况下的总土壤侵蚀量，最高的仍然是裸露梨园(CK处理)，而最低的则为幼龄梨园间作红薯(270.71kg／hm~2)。其它2个处理的总土壤侵蚀量分别是，幼龄梨园间作花生为1021.21 kg／hm~2，幼龄梨园间作旱稻为596.89kg／hm~2。梨-花生、梨-旱稻、裸露梨园三个处理的总土壤侵蚀量分别为梨-红薯处理的3.77倍、2.20倍和8.29倍。由此看出，在库区坡耕地种植果树的幼龄阶段，若地表无其它作物覆盖时，土壤侵蚀严重；另外，在幼龄果园间作不同种类的覆盖作物，土壤侵蚀量的差异明显，实际生产中选择适合的覆盖作物种类相当重要。 4、对4种处理的水土保持效果进行了比较，采用每10 mm降雨所造成的水土流失量作为比较基础，幼龄梨园地表裸露处理(对照)的水分流失率和土壤侵蚀量以100％计算，那么，其它3个间作处理与对照相比的相对降水保持率和土壤保持率(即比对照减少降雨流失量和土壤侵蚀量的百分比)分别是:幼龄梨园间作红薯为13.65%和87.93%:幼龄梨园间作花生为1033%和54.48%;幼龄梨园间作早稻为巧.77%和73.39%。梨一红薯处理的土壤保持能力在4个处理中属最强而保水能力则一般;梨一花生处理的保土保水能力相对较低:梨一早稻处理的保水能力在3个处理中为最高，而且保土能力也较强。 5、土壤有机物侵蚀试验结果表明，4个处理的被侵蚀土壤中有机物含量范围在3.01%一22.87%之间。若以3次降雨的平均值IOmm计算，梨一红薯、梨一花生、梨一早稻和裸地梨园各处理的被侵蚀土壤有机物含量分别为13.38%、13.41%、4.12%和3.81%。间作红薯和花生处理中由于播种时施用过农家肥而有机物含量较高，间作早稻和地表裸露处理的有机物含量相对较低。当然，无论哪种处理，随地表径流被侵蚀掉的土壤均是有机物含量较高的表层活化土壤。因此，即使发生了轻微的水土流失过程，它对土壤所造成的损害将是严重的。 6、同对照裸地梨园相比，梨一早稻、梨一红薯、梨一花生三种间作方式均可有效改善土壤的物理性质，但三种处理均导致了土壤全N、碱解N、全P、有效P的下降，仅仅有机质在梨一早稻的间作中表现为增加，这一研究结果与有些研究不一致(王玲玲，2002;樊巍，2002;吴荣兰，2003)，出现不一致甚至相反的实验结果，可能与间作时间短、取样深度有关。 7、三种间作处理使梨叶片叶绿素含量以及鲜叶比重都有不同程度的提高，其中以梨一早稻模式提高最为明显，鲜叶比重三次测定值分别增加29.49%，28.06%，25.78%，叶绿素含量则分别增加8.08%，1236%，4.25%.这一研究与吴荣兰(2003)、张士良(2003)发现梨园间作早稻后，梨园群体光合有明显增加具有一致性。 8、在梨园的短期经济效益上，四种处理以梨一早稻模式效果最为理想，产投比也较高，梨更多还原

【Abstract】 Orchard intercrop is a traditional grand utilization mode in three gorges reservoir area, which is effective in using resources and enhancing efficiency of resource use, and have good ecologic and economic values.But water and soil loss heavily in traditional pattern and can’t keep up with need of modern orchard, especially to many new slop-grand young orchard.Based on the orchard actuality,a jumped-up orchard intercrop pattern was fetched in.In this paper, we adopted investgation on the spot (integating local statistical datum) and experimenting outdoors. Four patterns, including pear dry rice,pear sweet potato,pear peanut and bare pear orchard were analysed.The results were as follows:1.Three gorges project is a very good opportunity to develop of fruit industry in the whole three gorges reservoir. We should change fruit distribution step by step. Fruit tree species matching and breed arranging must be reasonable for many new orchard. Many biggish potential fruit ,such as pear, plum, which holding high yield, ratio of output and devotion, average production value and fluctuating, should be selected to become main fruit tree species. Based on these analysis ,we fetched in a new intercrop pattern of young pear orchard intercropping dry rice.2. We added up three times rainfall and average during the whole experiment. Pathway depth (modulus) ranked in order from smallness to bigness: pear dry rice ,pear sweet potato, pear peanut and bare pear orchard. Results indicated that over 32.6% rainfall will loss by pathway, if crop doesn’t cover with the earth’s surface of orchard. Some crops holding robust roots can reduce modulus and rainfall remarkably, example .growing dry rice in orchard.3 .Lossing amount of water and soil of four patterns during three times added up to 100.86mm are the followings respectively: Lossing amount of water and soil of pear dry rice is160.857t/hm2, that of pear sweet potato is 188.981 t/hm2, that of pear peanut is 217.48 t/hm2 and that of bare pear is 328.814 t/hm2. Lossing amount of pear dry rice is the lowest and bare pear is reverse.Total amount of soil corroding of bare pear is also the highest(2243.43kg/ hm2 ),but that of pear sweet potato is reverse. Pear peanut, pear dry rice and bare pear is 3.77 time ,2.20 time and 8.29 time than that of pear sweet potato respectively. We can draw a conclusion that soil corroding is very serious in slop-pland young orchard if there are not crop covering with the earth’s surface of orchard. Besides, how to select intercrop crop is important ,because remarkable difference of soil corroding lied in different intercrop crop.4.Based on the amount of water and soil loss every 10mm rainfall and 100% of water and soil losing ratio of bare pear orchard, ratio of rainfall and soil preserving of other patterns are the followings; that of pear sweet potato is 13.65% and 87.93%,that of pear peanut is 10.33% and 54.48% and that of pear dry rice is 15.77% and 73.39%.Among 4 patterns, power of soil keeping ofpear sweet potato is the best,but that of rainfall keeping is common. Power of soil and rainfall keeping of pear peanut is relatively low. Power of rainfall keeping of pear dry rice is the best and that of keeping soil is good.5.The result of experiments with organic substance corrasion showed that content of organic substance is from 3.01% to 22.87%. Content of organic substance of corraded soil of Pear sweet potato is 13.38%,that of pear peanut is 13.41%,that of pear dry rice is 4.12% and that of bare pear orchard is 3.81%.The reason why content of organic substance of intercropping sweet potato and peanut is high is that fertilizer is used in seeding.Of course ,no matter which pattern.corraded soil with pathway hold plentiful organic substance.So little water and soil lossing have serious damage on soil.6. Compared with bare pear orchard ,other patterns can improve soil physical character.but the content of soil total N.available N.total P and available P fall.Only organic substance content increased in Pear dry rice. All these re更多还原