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[学术文献 ] 可持续发展背景下休耕制度的价值意蕴及对我国的启示 进入全文
中国农业资源与区划
休耕制度是落实藏粮于地、藏粮于技战略的有效途径，关乎国家粮食安全、生态环境保护和资源永续利用。[方法]综合运用归纳演绎法和理论分析法解析休耕制度的价值意涵，探讨面向可持续发展的中国耕地休耕制度的优化路径。休耕制度内涵与可持续发展目标（SDGs）内在价值趋同，主要特征有耕地休养环境的原真性、要素耦合与结构关联的贯通性、生态系统的自然完整性、空间均衡与效益统一的整体协同性；遵循自然规律、尊重基本国情是休耕制度的实施基础，尊重代表农民利益取向的意愿及选择是构建中国休耕方案的根本前提，深度挖掘耕地多功能及休耕前后价值变化是休耕制度有效实施的基本保障。我国休耕制度需结合碳达峰、碳中和战略目标，继续围绕数量配比、空间配置、路径实施等核心问题，推进实践诊断的精度深化和方案设计的尺度细化，不断强化体系建设与监管体制，夯实休耕制度的法治保障。
[学术文献 ] 南疆盆地亏缺灌溉和覆膜对油莎豆生物量及产量的影响 进入全文
干旱区研究
研究南疆盆地油莎豆（Cyperus esculentus L.）滴灌覆膜的效果和最适宜的灌溉制度，为构建南疆盆地油莎豆节水高产管理栽培模式提供参考。通过1 a的试验，在覆膜（M）和不覆膜（NM）条件下，设置3种水分处理水平，即：CK处理(对照，以当地常用灌溉量5316.45 m3·hm-2)、T1处理(灌溉量为3431.40 m3·hm-2)和T2处理(灌溉量为4133.85 m3·hm-2)，灌溉频率为6～10 d，研究覆膜和水分控制对油莎豆生长、品质、产量和水分利用效率的影响。结果表明：（1）油莎豆的密度受水处理的影响显著（P＜0.05），而根冠比受水处理影响不显著（P＞0.05）。（2）覆膜处理的草粗脂肪、可溶性淀粉、可溶性糖含量比未覆膜平均提高58.82%、3.35%和17.20%，覆膜处理块茎的粗脂肪含量、可溶性淀粉、可溶性糖含量均高于未覆膜的，分别增加了7.48%、2.56%和2.55%，且水处理间差异不显著（P＞0.05），但是均在T2处理达到最大。（3）产量和水分利用效率随灌溉量增加呈先增加后降低的趋势，其中覆膜条件下，T2处理的草和块茎的产量最大，分别为3974.55 kg·hm-2和5253.85 kg·hm-2，较CK处理分别显著增加6.45%和36.95%（P＜0.05），较未覆膜条件下，T2和CK平均产量显著增加29.41%和34.76%（P＜0.05），水分利用效率也在T2处理达到最大值，其中覆膜处理下，草和块茎在T2处理的水分利用效率较CK显著提高38.63%和34.33%（P＜0.05）；与T2（覆膜）处理相比，未覆膜条件下CK，T2处理的草和块茎的水分利用效率分别显著提高38.91%和34.33%（P＜0.05），覆膜处理对草的水分利用效率差异不显著（P＞0.05），但是对块茎的水分利用效率差异显著（P＜0.05）。因此，在覆膜条件下，灌溉定额为4133.85 m3· hm-2（T2）时，不仅提高了油莎豆的品质和产量，也提高了水分利用效率，节约水资源。
[学术文献 ] 不同灌溉模式寒区稻田温室气体排放与土壤矿质氮特征 进入全文
农业机械学报
为探究东北黑土区不同灌溉模式下稻田温室气体排放和土壤矿质氮特征，于2019年在黑龙江省庆安国家灌溉试验重点站测坑内进行了试验观测，按照不同的灌溉模式设置了控制灌溉（KG）、间歇灌溉（JG）和湿润灌溉（CI）3个试验处理，以当地常规的插秧淹灌（CK）为对照，研究了不同处理的稻田温室气体甲烷(CH4)和氧化亚氮(N2O)排放量、全球增温潜势值、以产量为基准的全球变暖潜势值及0～60 cm土壤NH4+-N含量和NO3--N含量的变化过程，以及0～20 cm土层土壤温度和矿质氮含量与CH4和N2O排放量的相关关系。结果表明，随着水稻生长发育进程的推进，各处理稻田土壤各土层温度均呈先升高后降低的变化趋势；各处理CH4和N2O排放量均呈先增加后减少的倒“V”形变化趋势，CH4和N2O的排放峰值分别出现在拔节孕穗期和抽穗开花期。从时间上来看，CK、JG、CI处理和KG处理的稻田土壤NH4+-N含量拐点分别出现在分蘖中期、抽穗开花期和拔节孕穗期、乳熟期，而所有处理的土壤NO3--N含量最大值均出现在分蘖前期；从空间上来看，不同处理稻田土壤NH4+-N平均含量随着土层深度增加而逐渐减少，而NO3--N平均含量CK处理随土壤深度逐步增加，其余各处理为先减少再增加变化趋势。土壤温度与CH4排放量有显著相关性，而与N2O排放量相关性不显著；各处理土壤NH4+-N含量与CH4和N2O排放量呈正相关，而土壤NO3--N含量与CH4和N2O排放量呈负相关。各处理稻田CH4累积排放量由大到小依次为CK、JG、KG、CI，N2O累积排放量由大到小依次为CI、KG、JG、CK，各处理CH4和N2O累积排放量均与CK处理差异性显著（P ＜ 0.05），从单位产量温室效应(GWPY)来看，KG、JG、CI处理分别较CK处理降低24.98%、27.69%和24.06%。研究结果可为东北黑土区稻田减排和提高土壤矿质氮利用率提供理论依据和技术支撑。
[学术文献 ] Multi-decadal analysis of water resources and agricultural change in a Mediterranean semiarid irrigated piedmont under water scarcity and human interaction 进入全文
ScienceDirect
Mediterranean piedmonts are an important hydro-agricultural systems. They constitute the junction between the mountains, where the streamflow is generated, and the surrounding plains, where the water is used. In Morocco, these traditional systems extend largely along the High Atlas Mountains. Yet, changing conditions in the Mediterranean basin as well as recurrent droughts in recent decades remain poorly understood in terms of hydrological and agricultural impacts, particularly in traditional hydro-agro-systems. The combined effects of climate variability and ineffective management of water resource dynamics may lead to increased water scarcity in these regions. The present work aims to assess the effects of climate variability and associated agricultural changes on water resources in a traditional irrigated piedmont of the Moroccan High Atlas. To that end, a trend analysis, together with change points detection, was carried out on annual and monthly precipitation, and streamflow from 1965 to 2018. Then, the standardized precipitation index (SPI) was employed to identify meteorological droughts. Also, groundwater, and spring discharge data were analyzed and discussed from 1973 to 2021. SPI outcomes revealed three major droughts, in 1981–1988, 1999–2008, and 2013–2018. Although the precipitation data showed no significant trend, except for Tahannaout station, the average annual precipitation over the piedmont area decreased by 28%. Similarly, streamflow decreased significantly by almost 40% for all stations, as did the Abainou spring's discharge. Consistent with that, groundwater level has declined dramatically over the past decades in the downstream piedmont. These decreases in water cycle components were tightly aligned with droughts. Yet, irrigation diversions were maintained in both dry and wet periods. Paradoxically, this decrease in water resources was associated with an agricultural transition from seasonal crops (cereals) to perennial crops (olive trees). This conversion is likely to amplify the water shortage, leading to groundwater resources overexploitation to satisfy the growing agricultural demand.
[学术文献 ] Surface water-groundwater interactions and local land use control water quality impacts of extreme rainfall and flooding in a vulnerable semi-arid region of Sub-Saharan Africa 进入全文
ScienceDirect
While extreme rainfall events may provide rare opportunities for replenishment of surface water and groundwater resources in vulnerable (semi)arid areas, they are typically also associated with widespread flooding. The impacts on contaminant movement associated with spatio-temporally complex relationships between surface water and groundwater during such events in these regions are largely unknown. The catchment area (∼4350 km2) upstream of Gaborone Dam on the Notwane River in south-east Botswana and northern South Africa experienced extreme rainfall and major flooding in 2016/17, following a severe 5-year drought. In this generally data-sparce area, we collected a unique data set that combined traditional water quantity observations with stable water isotope, major ion, trace metal and geophysical data. These were analysed to gain insights into water quantity and quality dynamics following flooding, including contaminant movement using trace metals as pollution indicators. Results revealed that the extreme rainfall and flooding was responsible for replenishment of surface water and groundwater resources, but also contaminant mobilisation from the surface. This subsequently resulted in increased concentrations of contaminants during the recession. Overall, hydrogeological heterogeneity dictated spatially variable surface water - groundwater interactions, characterised by poor connectivity in low productivity aquifer areas as opposed to good connectivity in moderate to high productivity aquifers. This in turn affected water quality dynamics and contamination, locally superimposed by land use impacts, primarily from urban landfill and local agricultural practices. Groundwater-connected streams had consistently lower (responses in) contaminants. We also found that Gaborone Reservoir facilitated prolonged conditions for recharge but likely also enhanced contamination of groundwater through maintaining a high water table in urban areas located immediately downstream. Management implications of our findings include a requirement for careful consideration of land use and landfill planning in relation to bedrock geology and presence of surface water reservoirs, conjunctive surface water and groundwater management, but also the need for even higher (space-time) resolution of monitoring in these data sparce environments. This could contribute to enhancing the benefits that extreme rainfall events provide in terms of surface water and groundwater resources replenishment for future dry seasons and periods of drought.
[学术文献 ] A seasonal smart market mechanism for sustainable groundwater management in agricultural regions 进入全文
ScienceDienct
The water market can be considered as a tool to reallocate water in a more efficient and equitable way in which both non-efficient and efficient users benefit from participating in the market by selling and buying their water quotas, respectively. The prerequisites on which an effective and efficient groundwater market relies is to consider both socio-economic and environmental factors. This paper aims to propose a seasonal smart groundwater market mechanism to improve production efficiency while adjusting the users' total water consumption to the available water. The proposed methodology provides the potential seasonal exchanges of groundwater entitlements among users and groundwater trading prices. Finally, a water banking mechanism based on the cooperative game theory is proposed to evaluate the effect of inter-basin water transfer on the proposed local groundwater market as well as sharing the benefits of water market between water donor and receiving basins. By applying the proposed methodology to the Nough region in central Iran, it is concluded that the average users' water productivity increases by 25% while satisfying environmental constraints. Based on the results of the market mechanism, the groundwater is fairly allocated to the agricultural users in proportion to the area of farms. After applying the water banking model, users in both the donor and receiving basins gained more profit than the status quo condition.
