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Ridge-furrow with plastic film mulching and various urea types have been applied in rainfed agriculture, but their interactive effects on potato (Solanum tuberosum L.) yield and especially environments remain poorly understood. A three-year experiment was conducted to explore the responses of tuber yield, methane (CH4) and nitrous oxide (N2O) emissions, net global warming potential (NGWP), carbon footprint (CF), and net ecosystem economic budget (NEEB) of rainfed potato to two mulching practices [plastic film mulching (RM) and no plastic film mulching (NM)] and three urea types [conventional urea (U), controlled-release urea (C), and a mixture of equal amounts of conventional urea and controlled-release urea at a ratio of 1:1 (CU)] and their interactions. The results showed that RM significantly decreased cumulative N2O emissions and CH4 uptake by 4.9% and 28.4%, but significantly increased NGWP by 8.9% relative to NM. Compared with U, the C and CU produced much lower cumulative N2O emissions and NGWP and higher CH4 uptake. The interaction of mulching methods and urea type had significant influence on tuber yield and NEEB. Considering both environment and production, RMCU could not only achieve a high tuber yield and NEEB (by up to 26.5% and 42.9%, respectively), but also reduce the CF (by up to 13.7%), and therefore should be considered an effective strategy for dryland potato.

Degraded soils (including salinized, eroded, and low organic matter) resulting from natural and human effects are universal in arid and semi-arid regions all over the world. Bentonite and humic acid (BHA) are increasingly being tested to remediate these degraded lands, with potential benefits on crop production and soil health. A field study was conducted to quantify the effects of BHA application at six rates (0, 6, 12, 18, 24, and 30 Mg ha−1) on (i) dynamic changes in soil properties and (ii) oat crop productivity parameters in a dryland farming ecosystem. The specific objective of this paper was to determine the residual effects four to five years after a one-time BHA application on soil health and crop performance. The findings demonstrated that with the increasing rates of one-time BHA application, soil profile water storage displayed a piecewise linear plus plateau increase, whereas soil electrical conductivity, pH, and bulk density were all reduced significantly (p < 0.05) in the 0−20 cm and 20−60 cm layers. The improved soil environments gave rise to an increased activity of soil enzymes urease, invertase, and catalase that, respectively, reached peak values of 97%, 37%, and 32% of the control at the rates of 18 to 24 Mg BHA ha−1. In turn, this boosted soil nutrient turnover, leading to a 40% higher soil available P. Compared with the control treatment, application of BHA at the estimated optimum rate (roughly 24 Mg ha−1) increased grain yield by 20%, protein yield by 62%, water use efficiency by 41%, and partial factor productivity of N by 20%. The results of this study indicated for the first time that a one-time BHA application would be a new and effective strategy to combat land degradation, drought, and promote a sustainable soil micro-ecological environment in dryland agroecosystems under a varying climate scenario.