Evaluating planning and delivery performance of Water User Associations (WUAs) in Osh Province, Kyrgyzstan

The primary objective of an irrigation organization is to provide efficient and effective management of water resources to achieve enhanced agricultural production. Performance assessment studies provide a tool to evaluate and promote this objective. The study examines the existing planning procedures and assesses irrigation performance of four Water User Associations (WUAs) located in Osh Province, Kyrgyzstan. Performance was evaluated using indicators of adequacy, efficiency, dependability and equity. Indicators were calculated for each irrigation season over the period 2003 to 2007. In general, all WUAs were found to be strong in terms of adequacy and efficiency standards. However, performance with respect to dependability and equity was poor. The results suggest that more effort is needed to improve temporal uniformity and equity in water distribution. In order to achieve this, estimations of irrigation requirements by WUA managers needs to be improved and mechanisms developed to request water in quantities, which are needed to maintain equity across the WUA outlets and among water users. The study concludes that the establishment of WUAs in Kyrgyzstan has helped to address the problem of water distribution and allocation among a large number of farmers. However, further training of farmers and managers is required to build their capacity to share water and ensure equity among users particularly during periods of less than optimal water supply. The findings of this research suggest that application of a pre-determined set of indicators can be a useful and cost effective tool to measure the performance of WUAs. This is particularly important for Central Asia where the performance of the recently established and state initiated WUAs to replace former collective farms is now a key element in future sustainable water management. The study identified uncertainties in the estimation of WUA water demands based on previous methods and suggests more attention and care required in calculating water requirements.     

Spatial stability of a plant-feeding nematode community in relation to macro-scale soil properties

Understanding the spatial stability of the plant-feeding nematode (PFN) community in agrosystems represents a fundamental step in the integrated control of some damaging species because modifications of soil properties in intensively managed agrosystems may allow growers to manipulate the balance between pathogenic and non-pathogenic species.In the present study, we tested the hypothesis that a community of four PFN species (Criconemella onoensis, Helicotylenchus erythrinae, Hemicriconemoides cocophillus, and Pratylenchus zeae) in a sugarcane agrosystem is spatially structured according to macro-scale soil properties. This hypothesis was studied by using a sugarcane field in Martinique in which soil properties had been heavily modified by hillock-leveling in the 1970s, resulting in a great variation in soil properties over a small area (20.8 × 16.0 m). The goal of the study was to measure the temporal stability of the PFN community spatial structure and to identify the soil parameters associated with differences in nematode abundance. A systematic sampling design was used to collect data in the field that were analyzed using co-inertia and STATIS-Coa. The field study was complemented by a greenhouse experiment.The field study documented the existence of a stable spatial pattern of the PFN community, a pattern that was structured in relation to macro-scale soil factors such as soil carbon, nitrogen, and phosphorus content and soil texture. The constant spatial pattern of the PFN community results from the differences in distributions among C. onoensis and the three other PFN species. C. onoensis was consistently more abundant in the deeply-leveled areas of the field, while the other PFN species were more abundant in the non-leveled areas. H. erythrinae was consistently more abundant in those parts of the field with higher soil pH and sodium content. These results suggested that soil properties can affect permanently the competitive balance among PFN species.The observed relationships between PFN and these macro-scale factors were validated in a greenhouse experiment with different ratios of soil from the leveled and non-leveled areas of the field site.Modification of some major soil properties (pH, Na⁺ content, soil organic content) by cultural practices such as hillock-leveling, fertilization, and liming, could greatly affect the balance among PFN species in agricultural fields.     

煤炭开采对区域农田植被碳库储量的影响评价

在人类煤炭开采活动的干预下,农田生态系统中碳储量迅速变化。这种变化不仅改变了土壤肥力及农田作物产量,而且对区域及全球环境具有很大影响,事实上稳定保持其碳库是农业减缓温室气体的主要途径。该文的研究目的就是从煤炭开采对区域农田植被碳库储量影响的角度来研究煤炭开采对农田生态系统碳储量的影响,以徐州九里矿区为研究区,通过区域内农田植被碳库采样与试验、区域植被碳库储量估算模型的构建以及碳储量估算得到九里矿区煤炭开采沉陷区农田植被的碳储量和碳密度分布图,然后与情景模拟得出的该区未受到煤炭开采影响情况下,经过几十年变化后农田植被的碳储量和碳密度分布图进行对比,得出煤炭开采对沉陷区范围的农田植被碳库的扰动影响,发现与不受到煤炭开采的影响相比,在沉陷区域外围地势较高的坡地煤炭开采对农田植被碳密度的影响很小,在沉陷区地势较低的季节性积水区和常年积水湿地区煤炭开采对农田植被碳密度的影响较大。在整个煤炭开采沉陷区范围内,与不受到煤炭开采的影响相比,煤炭开采沉陷区域农田植被碳库碳储量减少2.4万t。煤炭开采对区域农田植被碳库储量的影响属于失碳效应。     

Adaptation of the enchytraeid toxicity test for use with natural soil types

Assessments of chemical toxicity to soil invertebrates have been traditionally performed in formulated Standard Artificial Soil, or in standard LUFA 2.2 natural soil. Physical and chemical properties of these standard soils often do not represent the diversity of properties of natural soils and can be inadequate surrogates of exposure conditions of soil biota in the field. We investigated performance of three species of the genus Enchytraeus (E. albidus, E. crypticus, E. luxuriosus) using soil types covering a wide range of European and North American soil properties. Results showed that adult survival and juvenile production by E. albidus and E. luxuriosus were inhibited in acidic soils with pH ≤ 5, while less acidic soils having properties within following ranges: 2.5–8.0% OM, 6–26% clay, and 4–80% sand, could sustain survival and reproduction at or near validity criteria levels of enchytraeid toxicity test ISO/16387. Performance of E. crypticus in North American soils having properties within following ranges: 1.2–42% OM, 1–29% clay, and 4.4–8.2 pH, met or exceeded all validity criteria. Data established in our studies can be used for amending the validity criteria of current ISO/16387 when used with E. crypticus and OECD soil.     

我国农牧民补助奖励政策背景与成效

草原生态补助奖励政策是自2011年起实施的草原地区资金规模最大、受益农牧户最多的惠民政策,是通过给予农牧民补助奖励,支持鼓励农牧民合理利用草原、加快发展草牧业,解决人草畜矛盾的关键措施。中央政府不断完善政策内容、加大扶持力度,并按照“四到省”和“五到户”的原则,由地方政府结合地域实际创新性地落实政策,取得了显著的生态、经济和社会效益。与补奖前的2011年相比,草原鲜草产量提高了9.07%,植被综合盖度从51.0%提高到55.3%;政策执行以来,牛出栏率提高了1.3%,羊出栏率提高了4.2%,牧区和半农半牧区草食畜总量增加0.27亿头(只),实现了禁牧不禁养、减畜不减收的经济目标;政策通过转变畜牧业生产方式,实现了牧区人口转移,牧民对政策满意度高。当前,草原地区生产生态还不够协调平衡,人草畜矛盾尚未得到根本性解决,需要进一步完善农牧民补助奖励政策,促进草原保护建设和合理利用可持续发展。     

Runoff characteristics and its sensitivity to climate factors in the Weihe River Basin from 2006 to 2018

Exploring the current runoff characteristics after the large-scale implementation of the Grain for Green (GFG) project and investigating its sensitivities to potential drivers are crucial for water resource prediction and management. Based on the measured runoff data of 62 hydrological stations in the Weihe River Basin (WRB) from 2006 to 2018, we analyzed the temporal and spatial runoff characteristics in this study. Correlation analysis was used to investigate the relationships between different runoff indicators and climate-related factors. Additionally, an improved Budyko framework was applied to assess the sensitivities of annual runoff to precipitation, potential evaporation, and other factors. The results showed that the daily runoff flow duration curves (FDCs) of all selected hydrological stations fall in three narrow ranges, with the corresponding mean annual runoff spanning approximately 1.50 orders of magnitude, indicating that the runoff of different hydrological stations in the WRB varied greatly. The trend analysis of runoff under different exceedance frequencies showed that the runoff from the south bank of the Weihe River was more affluent and stable than that from the north bank. The runoff was unevenly distributed throughout the year, mainly in the flood season, accounting for more than 50.00% of the annual runoff. However, the trend of annual runoff change was not obvious in most areas. Correlation analysis showed that rare-frequency runoff events were more susceptible to climate factors. In this study, daily runoff under 10%-20% exceeding frequencies, consecutive maximum daily runoff, and low-runoff variability rate had strong correlations with precipitation, aridity index, and average runoff depth on rainy days. In comparison, daily runoff under 50%-99% exceeding frequencies, consecutive minimum daily runoff, and high-runoff variability rate had weak correlations with all selected impact factors. The sensitivity analysis results suggested that the sensitivity of annual runoff to precipitation was always higher than that to potential evaporation. The runoff about 87.10% of the selected hydrological stations were most sensitive to precipitation changes, and 12.90% were most sensitive to other factors. The spatial pattern of the sensitivity analysis indicated that in relatively humid southern areas, runoff was more sensitive to potential evaporation and other factors, and less sensitive to precipitation.     

白星花金龟主要习性及其群集为害玉米行为机制的初步研究

采用风洞试验法研究了白星花金龟群集为害玉米的行为机制。结果表明:鲜食甜玉米的穗在各器官中对白星花金龟成虫的诱集力最高,达85%;白星花金龟成虫或玉米螟幼虫为害玉米穗时对白星花金龟成虫有诱集作用,其选择系数分别为0.33和0.03,且白星花金龟成虫和玉米螟幼虫共同为害玉米穗时对白星花金龟成虫的诱集作用最强。通过室内饲养及野外观察初步明确了白星花金龟成虫昼夜取食、多次交尾、多次产卵及幼虫腐生、腹面朝上倒行等主要习性。     

一类整数规划问题的Lagrange求解方法

对企业人力资源培训问题,建立时间受限费用最小的分阶段培训的线性整数规划模型。并运用La-grange松弛的方法求解该模型,在所给的解法中Lagrange松弛问题可以分解为多个规模较小的子问题,而这些子问题容易求解并且可以并行计算,同时给出次梯度调整Lagrange乘子的方法。最后利用该方法求解某企业具体的培训计划,说明算法的有效性和实用性。     

基于MODIS卫星数据的黑龙江省生物质燃烧火点时空分布

生物质燃烧是重要的气候强迫因子,也是影响空气质量的重要污染源。黑龙江作为农林业大省,森林、草地、农业资源丰富,研究和分析黑龙江生物质燃烧情况,能够为秸秆资源综合利用、森林草原防火、环境质量改善等提供依据。本研究基于MODIS卫星数据、土地利用数据及高程数据,对黑龙江2010-2017年生物质燃烧火点时空分布特征进行了分析,包括秸秆焚烧火点、林火、草地野火。结果表明,黑龙江省火点主要集中在松嫩平原、三江平原以及小兴安岭中北部;黑河市火点占总火点的30%,齐齐哈尔次之,占16%;秸秆焚烧火点占总火点的68%,林火占32%。年内火点在春、秋两季最为明显,呈双峰分布,春秋季火点数占比分别为51%、45%。2010年以来林地与草地火点数量波动较小;秸秆焚烧火点数量自2014年起显著增加(P<0.05),2016年禁烧政策的开展下火点数量得到控制,秋季火点减少,但春季依旧呈现增加趋势。     

基于Landsat 8数据的荒漠土壤水分遥感反演

[目的]分析荒漠土壤水分变化特征,为南疆干旱区荒漠土壤水分遥感监测提供理论依据和方法支持。[方法]以Landsat 8数据构建干旱地区荒漠土壤水分建模指示因子,通过优选的26个光谱指数、地表温度(Ts)和地形数据(DEM)为建模因子,分别以偏最小二乘(PLSR)、支持向量机(SVM)和随机森林(RF)3种方法构建土壤水分反演模型,对模型进行验证和对比,选取最优模型反演空台里克土壤水分空间分布。[结果]①TVDI,NR,GLI等26个优选的光谱指数中,Ts和DEM与土壤水分均达极显著相关,可作为南疆干旱区荒漠土壤水分遥感建模的指示因子;②对比3种模型,RF模型建模集和预测集的R²分别为0.93,0.91,预测集RPD为3.90,各评价指标均为最高,PLSR模型精度次之,SVM模型精度最低;③以RF模型反演研究区表层土壤水分,在不同土地利用分类中土壤水分分布特征存在明显差异,特别在盐结皮区域的差异尤为突出。[结论]利用光谱指数、环境因子和地形数据构建的多因子、多指数综合的模型能较高精度地反演干旱区荒漠表层土壤水分,对研究该地区土地荒漠化和生态环境治理具有一定参考价值。