Research Progress of Different Fertilization Models in Farmland Based on Bibliometrics

In order to grasp the research status of different fertilization modes in China s farmland more comprehensively, with papers in core journals of Chinese Peking University collected in CNKI database from 2003 to 2022 as the main research object, this paper analyzed the research status of different fertilization modes from the perspectives of annual number of published papers, published journals, keywords and highly cited papers applying the bibliometrics research method. This study provides reference for the research in this field.

Effects of Different Fertilization Treatments on Biological Activity of Reclaimed Soil

As per randomized block design, the research had different fertilizer treatments, and the organic matter, respiration, enzyme activity and microbial carbon and nitrogen in reclaimed soil were studied. Fertilization schemes were as follows： The treatment without fertilizers（CK）, the treatment with chemical fertilizers（C）, the treatment with chemical fertilizers and bacterial fertilizer（CB）, the treatment with organic fertilizer and chemical fertilizers（CM）, and the treatment with chemical fertilizers, organic fertilizer and bacterial fertilizer（CMB）. The results showed： Four fertilization treatments could improve the content of soil organic matter. CMB, CM and CB could significantly improve the soil respiration. Organic fertilizer and fertilizer could significantly improve soil enzyme activity, In different growth stages the CMB treatment had highest urease and phosphatase.The most significant in the treatment content of sucrose was CM. Organic fertilizer and microbial fertilizer can significantly improve the microbial carbon and nitrogen in soil. For the microbial biomass carbon, the CMB treatment increased by 11%-34% than CB treatment, and 35%-63% than C treatment. In terms of microbial nitrogen CMB, CM respectively increased by 31%-51% than CB treatment, and 52%-100% compared with C. In the process of land reclamation, we should combine the organic fertilizer, microbial fertilizer and inorganic fertilizer. Only in this way can soil biological activity be accelerated, soil microbial environment improved, and the ripening increased soil nutrient and soil cultivation be enhanced.

Effects of different fertilizations on fruit quality,yield and soil fertility in field-grown kiwifruit orchard

Kiwifruit yield and quality and soil nutrients were investigated in a kiwifruit orchard after long-term fertilization to understand the relationship between kiwifruit growth and soil nutrition.Seven fertilization treatments with three replications were applied in a continuous four-year period,including no fertilizer(CK);phosphorus(P)and potassium(K)fertilizers(PK);N and K fertilizers(NK);N and P fertilizers(NP);N,P and K fertilizers(NPK);1.5 times of N,P and K fertilizers(1.5NPK);and chemical fertilizers plus swine manure(NPKM).Fertilization increased kiwifruit yield at the rate of 450 kg N/hm^(2),225 kg P2O5/hm^(2),300 kg K2O/hm^(2).The average yield decreased in a descending order for NPKM(44.6 t/hm^(2)),1.5NPK(42.6 t/hm^(2)),NPK(42.0 t/hm^(2)),NK(38.0 t/hm^(2)),NP(36.7 t/hm^(2)),PK(36.4 t/hm^(2))and CK(34.1 t/hm^(2)).The sugar to acid ratio(S:A)was the highest(10.9)in 2012,and the soluble sugar increased by 15.7%after four-year NPKM fertilization.The NPKM fertilization also significantly increased the vitamin C,soluble solid and firmness.The soil organic carbon contents at 0-20 cm,20-40 cm and 40-60 cm in depth under the NPKM treatment were 27%,29%and 139%higher than that of the CK treatment,respectively.The available N contents at 0-20 cm,20-40 cm and 40-60 cm in depth in the 1.5NPK treatment were 180%,114%and 133%higher than that in the CK treatment,respectively.Balanced fertilization with N,P,K and organic manure is important to soil fertility,which may increase yield and improve quality in field-grown kiwifruit orchard.

Effects of Nitrogen,Phosphorus,Potassium and CompoundFertilizer on Growth and Yield of Moringa Seedlings

In order to study the effects of different fertilizers on the growth and yield of Moringa seedlings,potted Moringa seedlings were randomly divided into 5 treatments:nitrogen(treatment 1),phosphorus(treatment 2),potassium(treatment 3),compound fertilizer(treatment 4)and non-fertilization(CK).The ground diameter,plant height,leaf,sprouting,crown width and yield of Moringa seedlings were measured one month later.The results showed that treatment 3 was beneficial to the growth of ground diameter of Moringa seedlings,which was 24.4%higher than CK(P<0.05).Treatment 4 significantly promoted plant height and leaf yield of moringa seedlings,being 56.8%and 76.9%higher than those of CK,respectively(P<0.05).Treatment 2 significantly promoted the sprouting of Moringa seedlings,being 53.8%higher than that of CK(P<0.05).Fertilization treatments had no significant effect on leaf size of Moringa seedlings(P>0.05).

Persistent low fertility among the East Asia descendants in the United States:perspectives and implications

We focus on a small but growing segment of the U.S.population,those who identify as Chinese,Japanese and Korean(CJK),and compare CJK fertility to other race/ethnic groups in the United States.CJK women in the U.S.exhibit a distinct,pervasive,and persistent pattern of late and low fertility with nearly all births occurring within marriage;this pattern displays a strong parallel to their counterparts in their countries of origin.To accompany this description,we offer a perspective on fertility difference that has broad applicability and that does not consistently predict that differences will disappear/remain.This discussion unites the literature on assimilation,segmented assimilation and pluralistic outcomes and processes.We also discuss the possible implications of these findings for country level policies to increase fertility.Most generally,these discussions are a corrective to demographer’s penchant for predicting secular change and convergence.