Subjects: Geosciences >> Geography submitted time 2021-02-28 Cooperative journals: 《干旱区地理》
Abstract： 利用阿勒泰地区 3 个高海拔西伯利亚落叶松（Larix sibirica）采样点的树轮样本，建立树轮宽 度区域标准化年表（DKH）。通过相关普查发现，DKH 年表与阿勒泰地区 7 个气象站当年 6 月平均 温度显著相关，相关系数为 0.705（P<0.00001），表明 6 月平均温度是影响树木年轮径向生长的主要 气候限制因子。用 DKH 年表可较好地重建该地区 1572—2014 年共 443 a 的初夏平均温度，解释方 差达 49.6%，经验证表明温度重建序列是可信的。温度变化特征分析表明：重建初夏温度经历了 10 个偏暖和 9 个偏冷阶段，其中 1605—1622 年和 1682—1723 年分别是最暖和最冷的阶段，1875— 1913 年和 1753—1804 年分别是持续时间最长的偏暖和偏冷阶段。存在 2.37~2.39 a、2.19 a 的显著 周期（P<0.05）和 73.50 a、14.00 a、7.30 a、2.29 a、2.21 a 的较显著周期（P<0.10）。在 1684 年、1719 年 前后均出现了由冷转暖的突变。空间相关分析表明文章重建的温度序列对阿勒泰地区温度具有 较好的空间代表性。本研究重建的初夏温度序列与阿勒泰西部 5—9 月平均温度和阿尔泰山南坡 温度序列相比较，具有较好的一致性。
Subjects: Biology >> Ecology submitted time 2017-11-29 Cooperative journals: 《中国生态农业学报》
Abstract： Apple is the fourth largest fruit of the world, apple area and production of china ranked first in the world. Longdong The Loess Plateau Lying in East Gansu Province is the dominant apple producing areas in china, and its area accounts for 11.11% and yield accounts for 8.75%(Gansu rural Year book 2015) .Apple has become a pillar industry to alleviate local poverty and become rich. Drought is one of the mainly limiting factors affecting the production of apple in rain-fed areas, and mulching is an important measure to ensure stable and higher yield of apple. A field experiment was designed to find the suitable measure on soil moisture conservation in apple orchards of Longdong. In 19-year-old Nagafu No.2 apple orchard, wheat straw mulching (WM), river sand mulching(SM), black plastic film mulching (FM) and clean tillage (CK) were applied to study its effects on orchard environment and growth and development of apple trees for three years(November 2010—November 2013),respectively. Results showed that from April to June the average soil moisture contents in 0~100cm soil layers of three mulching treatments were obviously higher(P<0.01) than CK, and the order of soil moisture contents was WM﹥SM﹥FM﹥CK. In the third year, water consumption in 0~500 cm of WM and SM were significantly (P<0.01) lower than CK from flower bud expanding stage to leaf canopy finished, and then then significantly (P<0.05)higher than CK from leaf canopy finished to maturity stage. Water consumption of FM treatment before and after leaf canopy finished was significantly (P<0.01)higher than CK. WM decreased soil temperature in 5~25 cm soil depth from March to August, and increased from September to November, but its daily amplitude of average soil temperature in 5~25 cm soil
Subjects: Biology >> Ecology submitted time 2017-11-29 Cooperative journals: 《中国生态农业学报》
Abstract： Apple is one of the four highest cultivated fruits in the world and the apple cultivated area and production in china is the highest in the world. Longdong, the Loess Plateau Lying in East Gansu Province, is the largest apple cultivation area in china, with apple cultivated area and yield accounting respectively for 11.11% and 8.75% of the total in the country (Gansu rural Year book 2015). Apple is a major industry towards the alleviation of local poverty and enrichment of the local people. While drought is one of the main limiting factors of apple production under rainfed conditions, and mulching is an important method for improving the yield of apple. A field experiment was designed to find a suitable measure of soil moisture conservation in apple orchards in Longdong. In a 19-year-old Nagafu No.2 apple orchard, wheat straw mulching (WM), river sand mulching (SM), black plastic film mulching (FM) and clean tillage (CK) were applied, the effects on the apple orchard environment and growth and tree development were observed for the period from November 2010 to November 2013. Results showed that from April to June, average soil moisture content in the 0–100 cm soil layers of the three mulching treatments was obviously higher than CK, significantly. Also the order of the amount of soil moisture content under the treatments was WM > SM > FM > CK. In the third year, soil water uptake from the 0–500 cm soil layer under WM and SM treatments was significantly lower than that of CK during the period from flower bud expansion stage to end of leaf canopy development. It was then significantly higher than that of CK for the period from end of leaf canopy development to maturity stage. However, total soil water use for all the treatments was slightly lower than CK. Soil water consumption under FM treatment was significantly higher than CK before and after leaf canopy development. Treatment WM reduced soil temperature in the 5-25 cm soil layer during the period from March to August, increased soil temperature from September to November, but average daily soil temperature amplitude for the 5-25 cm soil layer was always significantly lower than CK. Near-surface temperature decreased while relative humidity increased. Treatment SM had a slight effect on soil temperature, but obviously increased near-surface temperature while decreasing relative humidity. The soil temperature and daily amplitude of FM treatment from March to November were always higher than CK, and the near-surface temperature and relative humidity were close to CK. Three mulching treatments had no obvious effect on phenological period of apple. On the whole, the order of the content of nutrient in the 0-60 cm soil layer was WM > CK > FM > SM. The increase in almost all forms of nutrient was highest under WM treatment. However, organic matter, alkaline hydrolytic and total N in the 0–60 cm soil layer under SM treatment and in the 0–20 cm soil layer under FM treatment decreased obviously. Correspondingly, total salt content (including in the 0–20 cm soil layer under WM treatment) was significantly lower than CK. All the mulching treatments enhanced apple tree growth, but had little effect on shoot ratio. Those mulching treatments also increased single fruit weight and yield, of which WM treatment was significantly higher than that of CK. Water use efficiency of WM was significantly higher than other treatments, and the order was WM > SM > CK > FM. The results indicated that wheat straw mulching was better for apple orchard cultivation under rainfed conditions in Longdong. River sand mulching and black plastic film mulching should be added organic fertilizer and other nutrients into the soil of apple orchards in the region. The dominant single film mulching measure in the region needed to be perfected.
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