Contrasting effects of light, soil chemistry and phylogeny on leaf nutrient concentrations in cave-dwelling plants

Nutrient resorption from senescing leaves is one of the plants’ essential nutrient conservation strategies. Parameters associated with resorption are important nutrient-cycling constraints for accurate predictions of long-term primary productivity in forest ecosystems. However, we know little about the spatial patterns and drivers of leaf nutrient resorption in planted forests worldwide. By synthesizing results of 146 studies, we explored nitrogen (N) and phosphorus (P) resorption efficiency (NRE and PRE) among climate zones and tree functional types, as well as the factors that play dominant roles in nutrient resorption in plantations globally. Our results showed that the mean NRE and PRE were 58.98% ± 0.53% and 60.21% ± 0.77%, respectively. NRE significantly increased from tropical to boreal zones, while PRE did not significantly differ among climate zones, suggesting differential impacts of climates on NRE and PRE. Plant functional types exert a strong influence on nutrient resorption. Conifer trees had higher PRE than broadleaf trees, reflecting the adaptation of the coniferous trees to oligotrophic habitats. Deciduous trees had lower PRE than evergreen trees that are commonly planted in P-limited low latitudes and have long leaf longevity with high nutrient use efficiency. While non-N-fixing trees had higher NRE than N-fixing trees, the PRE of non-N-fixing trees was lower than that of N-fixing trees, indicating significant impact of the N-fixing ability on the resorption of N and P. Our multivariate regression analyses showed that variations in NRE were mainly regulated by climates (mean annual precipitation and latitude), while variations in PRE were dominantly controlled by green leaf nutrient concentrations (N and P). Our results, in general, suggest that the predicted global warming and changed precipitation regimes may profoundly affect N cycling in planted forests. In addition, green leaf nutrient concentrations may be good indicators for PRE in planted forests.

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Effects of transition from flood irrigation to drip irrigation on leaf nutrient concentrations of apple cv. Starkrimson Delicious

Journal of Plant Nutrition ◽

10.1080/01904167.2018.1485935 ◽

2018 ◽

Vol 41 (16) ◽

pp. 2085-2090

Author(s):

Kadir Uçgun ◽

Cenk Küçükyumuk ◽

Alamettin Bayav

Keyword(s):

Drip Irrigation ◽

Nutrient Concentrations ◽

Flood Irrigation ◽

Leaf Nutrient Concentrations

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Effect of Cover Crops on Yield and Leaf Nutrient Concentrations in an Organic Honeycrisp Apple (Malus domestica ‘Honeycrisp’) Orchard in Nova Scotia, Canada

HortScience ◽

10.21273/hortsci10615-16 ◽

2016 ◽

Vol 51 (11) ◽

pp. 1378-1383

Author(s):

Mehdi Sharifi ◽

Julia Reekie ◽

Andrew Hammermeister ◽

Mohammed Zahidul Alam ◽

Taylor MacKey

Keyword(s):

Nova Scotia ◽

Malus Domestica ◽

Cover Crops ◽

Cover Crop ◽

Red Clover ◽

Nutrient Concentrations ◽

Soil Productivity ◽

Total N ◽

Leaf Nutrient Concentrations ◽

K Concentration

There is an increasing interest for use of cover crops in orchards; however, the species that are most likely to be successfully implemented and their impact on yield and soil productivity have not been fully explored under Maritimes climate. This study investigated the effect of various cover crops treatments on organic apple (Malus domestica Borkh cv. Honeycrisp) yield and leaf nutrient concentrations in Nova Scotia over 3 years. Various cover crop mixtures including legumes, cereals, and grasses were planted using a modified Swiss Sandwich System (SSS). The cover crops treatments did not affect apple yield. In 2012, the input of biomass to the soil was 89% and 144% greater for alfalfa (ALF) and other cover crop treatments than unseeded (CON) treatment, respectively. The pea, oats, vetch mixture (POVM) contributed 24% higher biomass N to soil compared with average of other cover crops in 2012. Soil available K concentration in the tilled strip was increased in the 3rd year of the study compared with the initial values across cover crop treatments. The red clover oats mixture (RCOM), POVM, and Triple Mix (TM) treatments appeared to add the greatest amount of available K to the soil among treatments. The CON, TM, and ALF treatments resulted in higher leaf Mn concentration in only 2012 and CON, sweet clover and oats mixture (SCOM), and ALF resulted in higher leaf P concentration in 2014, compared with other treatments. Cover crops did not compete with apple trees and their most beneficial and consistent contribution was to total C, total N, and K input to the soil.

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