Organomineral fertilizer as an alternative for increasing potato yield and quality

ABSTRACT Organomineral fertilizer has great potential to replace synthetic fertilizers. The goal of this study was to determine an optimal substitution rate of organomineral fertilizer for mineral fertilizer to increase potato yield and quality. The experimental design was a randomized complete block with four replicates and six treatments, namely four substitution rates of organomineral fertilizer application (25, 50, 75, and 100% of mineral fertilizer demand), one rate of mineral fertilizer application (100% of mineral fertilizer demand), and the control (no fertilizer application). The organomineral application rates were tested as an alternative to substitute 25 to 100% of mineral fertilizer. The potato yield (total and in-class) and quality and plant and soil nutrient contents were monitored. The pH and total soluble solid contents had positive correlations with yield. Potatoes accumulated higher contents of K > N > P in the leaves, stems, and tubers. The organomineral fertilizer application rate of 3.7 t ha-1 (equivalent to 100% of mineral fertilizer demand) was the optimal rate to increase potato yield and quality. Organomineral fertilizer is a viable alternative to increase potato quality and yield and to increase plant and soil nutrient contents.

Decomposition characteristics of long-established Salix psammophila sand barriers in an arid area, Northwestern China

Salix psammophila has been extensively used as a sand barrier material for various desertification control applications. Elucidating the long-term decomposition characteristics and nutrient cycling process of this sand barrier in desert environments is of great importance. In this study, which was conducted for 1 to 9 years, changes in the mass loss percentage and the residual percentage in the decomposition process were explored of S. psammophila sand barriers in arid Northwestern China. In addition, the S. psammophila analysis nutrient elements release rule and its influence on soil properties were evaluated. The results showed that the decomposition process of S. psammophila sand barriers exhibited a “slow-fast” trend. After decomposition time for 9 years, mass decreased remarkably, and the residual percentage was 33.6%. Further, the nutrient release characteristics differed. C, P, and K were in the release state, whereas N was in the enrichment state. The decomposition percentage of the sand barriers was significantly correlated with N, P, K, C/N, C/P, and N/P (p < 0.05). The soil nutrient contents of C, P, and K contents increased 3.43, 2.23, and 2.08 g/kg compared to the initial values, respectively. The soil nutrient contents of N contents decreased 0.19 g/kg.

Impacts of Agricultural Land Reclamation on Soil Nutrient Contents, Pools, Stoichiometry, and Their Relationship to Oat Growth on the East China Coast

Agricultural land reclamation of coastal tidal land (CTL) with organic amendments may modulate the soil properties, and therefore promote crop growth. However, the linkages between soil nutrient contents, pools, stoichiometry, and crop growth under the supplement of organic amendments in CTL is limited. In this study, six treatments including the control (CK), organic manure (OM), polyacrylamide plus organic manure (PAM + OM), straw mulching plus organic manure (SM + OM), buried straw plus organic manure (BS + OM), and bio-organic manure plus organic manure (BM + OM) were conducted to explore these linkages in newly reclaimed CTL in Jiangsu Province, eastern China. The results showed that the application of different soil reclamation treatments increased soil nutrient contents, pools, and modulated their stoichiometric ratio, which thus promoted the growth of oat. Soil under all reclamation treatments increased the contents of surface soil organic carbon (SOC), total nitrogen (TN), and total phosphorus (TP), and the BM + OM treatment had the highest increase, which increased by 11.7–182.4%, 24.3–85.7%, 3.2–29.4%, respectively. The highest soil C pools were observed in the oat heading stage (36.67–41.34 Mg C ha−1), whereas the soil N and P pools were more stable during the oat growth period. Similarly, the highest surface soil C/N and C/P were observed in the oat heading stage (11.23–14.67 and 8.97–14.21), whereas the N/P in surface soil increased compared with the CK treatment during the oat growth period, with the exception of the filling stage. Land reclamation treatments significantly promoted oat growth by changing soil C, N, and P contents, pools, and stoichiometry, among which soil SOC, TN, TP, C/P, and N/P are more closely related to oat growth (p < 0.05).

Short-term effects of thinning on the development and communities of understory vegetation of Chinese fir plantations in Southeastern China

Background High-density conditions are global issues that threaten the sustainable management of plantations throughout the world. Monocultures and untimely management practices have identically resulted in the simplex of community structures, decreases in biodiversity, and long-term productivity losses in plantations China. The most popular measure which is commonly used to address these issues is thinning, which potentially results in increases in the development of understory plants in plantations. However, there is limited information currently available regarding the community composition of understory vegetation and the associated environmental factors, which has limited the sustainable management of China’s fir plantation ecosystems. Method In the present study, a thinning experiment was implemented which included a control check (CK: no thinning), as well as low intensity thinning (LIT: 20%), moderate intensity thinning (MIT: 33%), and high intensity thinning (HIT: 50%) in Chinese fir plantations located in the Southeastern China. During the investigation process, the understory vegetation examined three years after thinning measures were completed, in order to analyze the impacts of different thinning intensities on the growth and community composition of the understory plants. At the same time, the associated environmental factors in the fir plantations were also investigated. Results The species richness, total coverage, and biomass of the understory vegetation were observed to be apparently increased with increasing thinning intensity. In addition, it was found that the thinning measures had prominently influenced the soil nutrients. The community compositions of the understory vegetation were significantly different among the four thinning intensity levels, especially between the CK and the HIT. Furthermore, the development of the understory vegetation was found to be significantly correlated with the soil nutrient contents, and the community compositions of the understory vegetation were prominently driven by the tree densities, slope positions, and soil nutrient contents.