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Soil respiration (CO2 emission to the atmosphere from soils) is an important component of the global carbon cycle. In highly seasonal ecosystems the magnitudes and the underlying mechanisms that control soil respiration (RS) are still poorly understood and measurements are underrepresented in the global flux community. In this dataset, systematic and monthly measurements of RS were conducted with an infrared gas analyzer coupled to a static chamber during 2015, 2016, 2017 and 2019 in a tropical dry forest with a land use history from Northwestern México. These data is useful to assess the intra-annual and seasonal variations of RS at a highly seasonal dry forests and serves as a base line to benchmark soil carbon models in regional and global contexts. The data presented supports the research manuscript: "Soil respiration is influenced by seasonality, forest succession and contrasting biophysical controls in a tropical dry forest in Northwestern Mexico" from Vargas-Terminel et al. [1].

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A field experiment was carried out to quantify the effect of a native bacterial inoculant on the growth, yield, and quality of the wheat crop, under different nitrogen (N) fertilizer rates in two agricultural seasons. Wheat was sown under field conditions at the Experimental Technology Transfer Center (CETT-910), as a representative wheat crop area from the Yaqui Valley, Sonora México. The experiment was conducted using different doses of nitrogen (0, 130, and 250 kg N ha-1) and a bacterial consortium (BC) (Bacillus subtilis TSO9, B. cabrialesii subsp. tritici TSO2T, B. subtilis TSO22, B. paralicheniformis TRQ65, and Priestia megaterium TRQ8). Results showed that the agricultural season affected chlorophyll content, spike size, grains per spike, protein content, and whole meal yellowness. The highest chlorophyll and Normalized Difference Vegetation Index (NDVI) values, as well as lower canopy temperature values, were observed in treatments under the application of 130 and 250 kg N ha-1 (the conventional Nitrogen dose). Wheat quality parameters such as yellow berry, protein content, Sodium dodecyl sulfate (SDS)-Sedimentation, and whole meal yellowness were affected by the N dose. Moreover, the application of the native bacterial consortium, under 130 kg N ha-1, resulted in a higher spike length and grain number per spike, which led to a higher yield (+1.0 ton ha-1 vs. un-inoculated treatment), without compromising the quality of grains. In conclusion, the use of this bacterial consortium has the potential to significantly enhance wheat growth, yield, and quality while reducing the nitrogen fertilizer application, thereby offering a promising agro-biotechnological alternative for improving wheat production.

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Mexico ranks second in shrimp (Litopenaeus vannamei) production of in Latin America with significant annual growth, however, during 2011 shrimp production fell by almost 50 % due to the presence of the white spot syndrome virus (WSSV). In this context, a life cycle analysis (LCA) and data envelopment analysis (DEA) were performed on 76 commercial farms severely affected by the presence of WSSV in northwestern Mexico. The application of this combined methodology allowed a detailed quantification of different environmental impact categories. During the presence of WSSV, there was a negative effect on the feed conversion ratio (FCR) (>40 %), higher consumption of seawater (38 %), and energy (38 %). Consequently, operational outputs related to the discharge of nitrogen and phosphorus increased by 60 and 57 %, respectively. Similarly, CO2 emissions, increased by 38 % relative to a typical year of production. Overall, the main critical points in the impact categories analyzed are related to food (98 %), use of diesel (23 %), and rearing (24 %), dominating pollutants emissions in all categories. Consequently, an improvement scenario was evaluated related to innovation in the formulation of foods supplied with immunostimulants, which confer protection against pathogenic microorganisms. This scenario lead to a reduction environmental impact of about 82 %. The results of this analysis will be a useful resource in the design of mitigation strategies with innovation processes that allow maintaining yields for shrimp producers in this region and at the same time reduce the environmental impacts generated.

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The objective of this work is to present a long-term dataset of water stable isotopes in rainfall samples from northwestern Mexico. These data is useful to generate a local meteoric water line as a reference tool for atmospheric and ecohydrological studies within the North American Monsoon region and to compare across the globe. This work shows the isotopic variation of the rainfall collected at a permanent location in Ciudad Obregon, Sonora, Mexico (27.511850, -109.956316), between 2014 and 2021. The isotopic composition of 138 rain samples was analyzed for both oxygen (δ18O) and deuterium (δ2H) with laser spectroscopy. The slope of the resulting local meteoric water line was m = 6.59 with an intercept of -1.15 (R² = 0. 91). During the monitored period at the studied region the presence of hurricanes, cold fronts and the hegemony of rainfall attributed to the North American Monsoon is recorded in the dataset.

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Theories attempting to explain species coexistence in plant communities have argued in favour of species' capacities to occupy a multidimensional niche with spatial, temporal and biotic axes. We used the concept of hydrological niche segregation to learn how ecological niches are structured both spatially and temporally and whether small scale humidity gradients between adjacent niches are the main factor explaining water partitioning among tree species in a highly water-limited semiarid forest ecosystem. By combining geophysical methods, isotopic ecology, plant ecophysiology and anatomical measurements, we show how coexisting pine and oak species share, use and temporally switch between diverse spatially distinct niches by employing a set of functionally coupled plant traits in response to changing environmental signals. We identified four geospatial niches that turned into nine, when considering the temporal dynamics of the wetting/drying cycles in the substrate and the particular plant species adaptations to garner, transfer, store and use water. Under water scarcity, pine and oak exhibited water use segregation from different niches, yet under maximum drought when oak trees crossed physiological thresholds, niche overlap occurred. The identification of niches and mechanistic understanding of when and how species use them will help unify theories of plant coexistence and competition.

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Chronological measurements of litterfall production can be used for understanding ecosystem dynamics such as net primary production and carbon cycling in highly seasonal ecosystems such as tropical dry forests (TDF). This paper presents data on litterfall production and meteorology in an old-growth TDF. The data was generated within the Monte Mojino Reserve located in the Sierra de Alamos - Rio Cuchujaqui Natural Protected Area in northwestern México. For litterfall collection, twenty randomly placed litterfall traps were installed to collect monthly litterfall production across four full growing seasons (48 monthly collections). Meteorological data were obtained from an automatic micrometeorological station that recorded data in situ from January 2013 to March 2019. The database includes litterfall production [g m-2 month-1], monthly rainfall [mm], air temperature [°C], relative humidity [%] and photosynthetic active radiation [µmol m-2 s-1].

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It is well known that remote sensing is a series of procedures which detects physical characteristics of the earth surface by remotely-measuring its reflected and emitted radiation using cameras or sensors. Lately, the increasing use of unmanned aerial vehicles (UAVs) as remote sensing platforms and the development of small-size sensors have resulted in the expansion of continuous monitoring of earth surface at smaller spatial scales. For this reason, the integration of UAV- and consumer-grade cameras can be useful to acquire surface characteristics at plot or footprint scale. This dataset contains 314 aerial images covering an area of aproximately 18,800 m2 within the footprint of an Eddy covariance and meterorological station. The monitoring site was deployed at "El Soldado" estuary (27°57'14.4″ N and 110°58'19.2″ W) located in the southern coast of the Mexican State of Sonora. UAV flight path was programmed to flight in autonomous mode with an altitude of 30 m, a velocity of 5 m/s and a frontal and side overlap of 85 and 75% respectively. This dataset was created to support mapping surveys for surface classification and site description. This dataset is aimed to support researchers, stakeholders and general public interested in coastal areas, natural resources management and ecosystem conservation. Finally, this dataset could be also used for those interested in digital photogrammetry and 3D reconstruction as benchmark example to develop high resolution orthomosaics.

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An experiment was carried out to evaluate the effect of increased temperature on roots and leaf water and osmotic potential, osmotic adjustment (OA) and transpiration on Triticum durum L. (CIRNO C2008 variety) during growth (seedling growth), tillering and heading phenophases. Wheat was sown under field conditions at the Experimental Technology Transfer Center (CETT-910), as a representative wheat crop area from the Yaqui Valley, Sonora México. Thermal radiators were placed at 1.20 m from the crop canopy. Treatments included warmed plots (2 °C) and ambient canopy temperature with five replicates. Temperature treatment was controlled using a (proportional, integrative, derivative) feedback control system on plots covering a circular area of r = 1.5 m. Results indicated a significant decrease in the osmotic potential of roots and leaves for the warmed plots. Water potential, under warming treatment, also experienced a significant reduction and a potential gradient was observed in both, roots and leaves, while the phenophases were delayed. Such results demonstrate that, under warmer conditions, plants increase water absorption for cooling. Hence, transpiration experienced a significant increase under warming in all phenophases that was related to the low root and leaf water potential. CIRNO C2008 also experienced OA in all phenophases with glycine betaine as the osmolyte with major contribution.

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This work evaluates the experimental warming effects on phenology and grain yield components of wheat in the Yaqui Valley, Sonora, México, using CIRNO C2008 variety from Triticum durum L., as a model during the cropping cycle of 2016-2017 (December to April). Infrared radiators were deployed to induce experimental warming by 2 °C above ambient crop canopy temperature, in a temperature free-air controlled enhancement system. Temperature was controlled by infrared temperature sensors placed in eight plots which covered a circle of r = 1.5 m starting five days after germination until harvest. The warming treatment caused a reduction of phenophases occurrence starting at the stem extension phenophase. Such phenological responses generated a significant biological cycle reduction of 14 days. Despite this delay, CIRNO C2008 completed its biological cycle adequately. However, plant height under the warming treatment was reduced significantly and differences were particularly observed at the final phenophases of the vegetative cycle. Plant height correlated negatively with spikes length, spikes mass, and number of filled grains. Warming also reduced grain yield in 33%. The warming treatment caused a stress intensity (SI = 1-yield warming/yield control) of 39.4% and 33.2% in biomass and grain yield, respectively. The differences in stress intensities between biomass and grain yield were based on plant height reduction. Grain mass was not affected, demonstrating the crop capability for remobilization and adequate distribution of elaborated substances for the spikes under warming conditions.

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Global modeling efforts indicate semiarid regions dominate the increasing trend and interannual variation of net CO2 exchange with the atmosphere, mainly driven by water availability. Many semiarid regions are expected to undergo climatic drying, but the impacts on net CO2 exchange are poorly understood due to limited semiarid flux observations. Here we evaluated 121 site-years of annual eddy covariance measurements of net and gross CO2 exchange (photosynthesis and respiration), precipitation, and evapotranspiration (ET) in 21 semiarid North American ecosystems with an observed range of 100 - 1000 mm in annual precipitation and records of 4-9 years each. In addition to evaluating spatial relationships among CO2 and water fluxes across sites, we separately quantified site-level temporal relationships, representing sensitivity to interannual variation. Across the climatic and ecological gradient, photosynthesis showed a saturating spatial relationship to precipitation, whereas the photosynthesis-ET relationship was linear, suggesting ET was a better proxy for water available to drive CO2 exchanges after hydrologic losses. Both photosynthesis and respiration showed similar site-level sensitivity to interannual changes in ET among the 21 ecosystems. Furthermore, these temporal relationships were not different from the spatial relationships of long-term mean CO2 exchanges with climatic ET. Consequently, a hypothetical 100-mm change in ET, whether short term or long term, was predicted to alter net ecosystem production (NEP) by 64 gCm(-2) yr(-1). Most of the unexplained NEP variability was related to persistent, site-specific function, suggesting prioritization of research on slow-changing controls. Common temporal and spatial sensitivity to water availability increases our confidence that site-level responses to interannual weather can be extrapolated for prediction of CO2 exchanges over decadal and longer timescales relevant to societal response to climate change.

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