Spatial Variability of Electrical Conductivity of Desert Soil Irrigated with Treated Wastewater: Implications for Irrigation Management

Knowledge of spatial variability is important for management of land affected by various anthropogenic activities. This study was conducted at West Mesa land application site to determine the spatial variability of electrical conductivity (EC1:1) and suggest suitable management strategy. Study area was divided into five classes with EC increasing from class I to V. According to the coefficient of variation (CV), during 2009 and 2010, EC1:1 values for different classes were low to moderately variable at each depth. Semivariogram analysis showed that EC1:1 displayed both short and long range variability. Area coverage of classes I and II were much higher than classes III, IV, and V during 2009. However, during 2010 area coverage decreased from 26% to 14.91% for class II, increased from 12.11% to 22.97%, and 10.95% to 20.55 for classes IV and V, respectively. Overall area under EC1:1≥ 4 dS/m increased during 2009. Soil EC map showed EC classes IV (4.1–5 dS/m) and V (>5.1 dS/m) were concentrated at northwest and southeast and classes I and II were at the middle of the study plot. Thus, higher wastewater should be applied in the center and lower in the northwest and southwest part of the field

Improving the Chile Industry of New Mexico Through Industry, Agriculture Experiment Station, and Cooperative Extension Service Collaboration: A Case Study

Chile growers and the Agricultural Research and Cooperative Extension Services at New Mexico State University have a long history of collaboration to sustain the chile industry. This case study identifies and documents the methodology of creating collaboration among the Agriculture Experimental Station, Cooperative Extension, and growers to solving local, regional, and global challenges in a specialty crop. A new paradigm has been created with the formation of a research-team approach with long-term funding guaranteed and the New Mexico Chile Growers Association\u27s direct involvement to determine the allocation of research funds to the team and other funding requests

Components of phenotypic variance of seed traits and germination characteristics of 20 ponderosa pine half-sib families

Abstract A study was conducted to estimate phenotypic variance components of seed traits and seed vigor of 20 ponderosa pine seed lots. A high intraspecific within-group variation in seed germination and seedling growth has been observed in both half-sib and full-sib families of conifers. Some seed traits may influence seed lot quality and seedling survival. Wind-pollinated cones were collected from 20 ponderosa pine maternal trees, 10 cones per tree, in a stand located in Fort Defiance, Arizona. Air-dried seeds were sown under laboratory conditions, by using a completely randomized design to estimate components of phenotypic variance for seed weight (SW), seed coat weight (SCW), seed imbibition (IMB), five germination characteristics, and three Weibull parameters (a, b and c). About 80% of size classes had a seed weight (SW) e» 41 mg and e» 97% final germination. The within-plot (within- family) variance component for SW (64.5%) and IMB (70.4%) was higher than among-family variation (35.3 and 24.8%, respectively). The among-family component varied from 35.1% (Weibull parameter a) to 62.3% (Peak Value). Results suggest a significant maternal contribution and a high within-family genetic influence on seed quality and germination characteristics. Finally, heavier seeds (SW e» 60 mg), whose time of germination (TOG) occurred at day 3, increased 38.3% of their seed weight due to water absorption before reaching 50% germination; on the other hand, seeds whose SW was e» 45 mg and TOG = 7, showed 102.2% increase in SW before reaching 50% germination. Resumen Se realizó un estudio para estimar componentes de varianza de características y vigor de 20 lotes de semilla de pino ponderosa. En familias de hermanos completos y medios hermanos la varianza dentro de grupos es elevada para la germinación y crecimiento de plántulas de coníferas. Algunas características de semilla pueden influir en la calidad del lote y la supervivencia de plántulas. Diez conos de polinización abierta fueron colectados de cada uno de 20 árboles madre, en una población localizada en Fort Defiance, Arizona. Semillas secadas al aire fueron sembradas en el laboratorio, en un diseño completamente aleatorizado, para estimar las componentes de varianza fenotípica de: peso (SW) y cubierta de la semilla (SCW); imbibición de la semilla (IMB), cinco características germinativas y tres parámetro de Weibull (a, b y c). Un 80% de la semilla tuvo peso e» 41 mg y germinación e» 97%. La varianza dentro de progenie/dentro de familia para las características SW (64.5%) e IMB (70.4%) fue mayor que la varianza entre familias (35.3 y 24.8%, respectivamente). La varianza entre familias varió de 35.1% (parámetro a de Weibull) a 62.3% (Peak Value). Los resultados sugieren contribución materna y componente genética alta dentro de familias que influyen en la calidad y características germinativas de la semilla. Semillas con SW e» 60 mg y TOG=3, incrementaron 38.3% de su peso por agua absorbida para alcanzar 50% de germinación. Las semillas cuyo SW fue e» 45 mg and TOG = 7, mostraron un incremento de 102.2% en SW antes de completar 50% de germinación

Fly Ash and Composted Biosolids as a Source of Fe for Hybrid Poplar: A Greenhouse Study

Soils of northwest New Mexico have an elevated pH and CaCO3 content that reduces Fe solubility, causes chlorosis, and reduces crop yields. Could biosolids and fly ash, enriched with Fe, provide safe alternatives to expensive Fe EDDHA (sodium ferric ethylenediamine di-(o-hydroxyphenyl-acetate)) fertilizers applied to Populus hybrid plots? Hybrid OP-367 was cultivated on a Doak sandy loam soil amended with composted biosolids or fly ash at three agricultural rates. Fly ash and Fe EDDHA treatments received urea ammonium nitrate (UAN), biosolids, enriched with N, did not. Both amendments improved soil and plant Fe. Heavy metals were below EPA regulations, but high B levels were noted in leaves of trees treated at the highest fly ash rate. pH increased in fly ash soil while salinity increased in biosolids-treated soil. Chlorosis rankings improved in poplars amended with both byproducts, although composted biosolids offered the most potential at improving Fe/tree growth cheaply without the need for synthetic inputs

Evaluation of Spatial and Temporal Root Water Uptake Patterns of a Flood-Irrigated Pecan Tree Using the HYDRUS (2D/3D) Model

Quantitative information about the spatial and temporal patterns of compensatory root water uptake (RWU) in flood-irrigated pecan orchard is limited. We evaluated spatio-temporal compensated and uncompensated RWU patterns of mature pecan tree in a silty clay loam orchard using the HYDRUS (2D/3D) model. HYDRUS (2D/3D) simulations, which agreed well with measured water contents and temperatures at different soil depths and horizontal distances from the tree trunk, suggested that while both compensated and uncompensated RWU varied with soil depth they did not do so laterally because of similar spatial vertical distributions of root length density (RLD) for the under-canopy and the tree canopy dripline locations. Considering compensated RWU resulted in an increase in actual transpiration by 8%, and a decrease in evaporation and drainage by 5% and 50%, respectively, during a growing season. Simulated transpiration and relative transpiration (a ratio between actual and potential transpiration) values were correlated with measured transpiration and plant-based water stress indicators (stem and leaf water potentials), respectively. Overall, our results of the spatio-temporal compensatory RWU provide support to use HYDRUS (2D/3D) as a tool for managing efficient water use of pecan. © 2013 American Society of Civil Engineers. ASCE/AUGUST 2013

Plasticity in dendroclimatic response across the distribution range of Aleppo pine (Pinus halepensis)

We investigated the variability of the climate-growth relationship of Aleppo pine across its distribution range in the Mediterranean Basin. We constructed a network of tree-ring index chronologies from 63 sites across the region. Correlation function analysis identified the relationships of tree-ring index to climate factors for each site. We also estimated the dominant climatic gradients of the region using principal component analysis of monthly, seasonal, and annual mean temperature and total precipitation from 1,068 climatic gridpoints. Variation in ring width index was primarily related to precipitation and secondarily to temperature. However, we found that the dendroclimatic relationship depended on the position of the site along the climatic gradient. In the southern part of the distribution range, where temperature was generally higher and precipitation lower than the regional average, reduced growth was also associated with warm and dry conditions. In the northern part, where the average temperature was lower and the precipitation more abundant than the regional average, reduced growth was associated with cool conditions. Thus, our study highlights the substantial plasticity of Aleppo pine in response to different climatic conditions. These results do not resolve the source of response variability as being due to either genetic variation in provenance, to phenotypic plasticity, or a combination of factors. However, as current growth responses to inter-annual climate variability vary spatially across existing climate gradients, future climate-growth relationships will also likely be determined by differential adaptation and/or acclimation responses to spatial climatic variation. The contribution of local adaptation and/or phenotypic plasticity across populations to the persistence of species under global warming could be decisive for prediction of climate change impacts across populations. In this sense, a more complex forest dynamics modeling approach that includes the contribution of genetic variation and phenotypic plasticity can improve the reliability of the ecological inferences derived from the climate-growth relationships.This work was partially supported by Spanish Ministry of Education and Science co-funded by FEDER program (CGL2012-31668), the European Union and the National Ministry of Education and Religion of Greece (EPEAEK- Environment – Archimedes), the Slovenian Research Agency (program P4-0015), and the USDA Forest Service. The cooperation among international partners was supported by the COST Action FP1106, STREeSS

Noncommensurable values of the pecan industry

Guide containing in information on the community benefits of pecan production in New Mexico and West Texas beyond nut production and profit

Variación entre procedencias y respuesta a la poda química en plántulas de Pinus Greggii.

Se evaluó la respuesta a la poda química de raíz de las plántulas de nueve procedencias pertenecientes a las dos regiones (variedades) de Pinus greggii Engelm. en vivero y en campo. Las plántulas crecieron durante seis meses en invernadero en contenedores tratados o no con cobre. La poda química de raíz mejoró la altura, el diámetro a la base y peso seco de la parte aérea de las plantas tanto en el vivero como en campo, en comparación con las no tratadas. Después de nueves meses en campo en Nuevo México las plantas tratados con cobre fueron 5% más altas, con 4% más diámetro a la base, 8% mayor peso seco de la parte área y 3.6% de la raíz, y con mayor supervivencia (90 vs. 87%). Hubo diferencias significativas en las plántulas entre las procedencias del norte y las del sur en vivero y en campo. Las plántulas del sur fueron 71% más altas, con un diámetro a la base 7% mayor, y un peso seco aéreo 23% mayor que las plántulas de las procedencias norteñas después de nueve meses en el campo. Sin embargo, el peso seco radical fue 14% mayor en las segundas. Consecuentemente, las plántulas de las procedencias del norte tuvieron mayor relación raíz:tallo (0.38 vs. 0.27) y mayor supervivencia (94 vs. 84%). Hubo interacción significativa entre la poda química y la procedencia sólo para peso seco de la parte aérea, donde las plántulas de Los Lirios no respondieron significativamente al cobre en el vivero. Los resultados de esta investigación apoyan el uso de las procedencias norteñas (var. greggii) para sitios limitativos y las procedencias del sur (var. australis) en condiciones ambientales más favorables